Right Side Up: A History of the Space Transportation System

Chapter 1: Preflight
  • “In short, the Space Shuttle is so inefficient because it is built upside-down.”


    Chapter 1: Preflight


    Technicians swarmed around the gleaming white delta-winged shape, mostly around the nose and tail, but some at strategic points along the length, at the engine bays, the landing gear wells, and the control surfaces on the aft side of the wings. The ship’s gleaming white aluminum skin was inspected, with sections yellow or browned with use cleaned and checked. The more resistant titanium armor on the belly, the blunt nose, and the wing leading edges was checked as well. The mighty F-1B engines were inspected and, where needed, swapped out for maintenance. Though they were rated for many more flights, this was to be the highest-profile mission yet in the Space Shuttle program—no one at Boeing or at NASA wanted to take chances now.

    Several long gray cables trailed from two boxes embedded into the walls of the flight deck to the hangar floor, where they plugged into a console atop which sat a bulky CRT monitor. Green text on a black background reflected off an engineer’s glasses as he inspected the stored flight data from the last test flight and as his teammates checked that the computer, responsible for the fly-by-wire actuation of the control surfaces, measurement of fuel levels, and the limited life-support capacity of the flight deck, and countless other systems, responded properly to simulated inputs. The comparatively modern IBM AP-101 was a massive leap over the core rope that had graced the Apollo Guidance Computer, and enabled a lot more functions to be off-loaded to the vehicle--and given the flight regime for which it was designed, that was necessary.

    Behind an access panel between the LOX tank forward bulkhead and the flight deck hatch, a technician ran a very careful low-power test of one particular circuit, the one that controlled the pyrotechnics that fired the escape pod. A far cry from the launch-abort towers that had protected the Apollo astronauts, but still far better than the ejection seats with which the Gemini crews had had to make do, this system ensured the survival of the crew should the worst happen. This was something the technician was unable to forget, with her supervisor looking over her shoulder at the multimeter in her hand, and with a poster of Snoopy in an orange flight suit reminding her that “Mission success is in YOUR hands!” hanging on the hangar wall. The results checked out, verified by the supervisor with a little help from his pocket calculator--a new model, with an LCD display—as far as they could tell, this system was good to go. The supervisor checked that particular circuit off of the dot-matrix checklist on his clipboard, and they moved on to testing the redundant and triple-redundant back-ups. This particular access point was located near the top of the vehicle--by the light filtering in through open access panels all around, the technician could just make out the yellow-painted bulk of the LOX tank’s forward bulkhead, and the small propellant tanks that fed the separation motors and reaction-control thrusters. Even with those here, the nose of the vehicle was a cavernous void--a vestige of the original design scheme, which had called for the nose to retract back into that void.

    Around the hangar, similar inspections ultimately yielded the same results. All five engines were flight-worthy, the control surfaces demonstrated exactly the desired range of motion, the hydraulic actuators that controlled the covers over the jet engines performed as expected, landing gear wheels rotated freely, and the dials on the flight deck were all illuminated perfectly. The last hatches were dogged shut, umbilical cables pulled out, and access ladders wheeled away as an airport tow truck with a bright-red NASA worm on its front and sides rolled in. Pinned securely to the truck, the spacecraft left the fluorescent lighting of the hangar for Florida’s brighter morning sun, the massive American flag painted on each side of her fuselage breaking up her otherwise clean white appearance.

    RS-IC-102, “Constitution,” had a date in the VAB.


    The transition from a Saturn V first stage to the reusable booster of the Space Transportation System seems obvious and natural in hindsight, almost two decades removed from the birth of either system. However, the Reusable Booster had a much more complex history than many assume, and a close study of the complex origins of the idea illustrates how the most “optimal” design in aerospace can depend on a variety of definitions. Marshall Space Flight Center funded the first studies of what eventually became RS-IC in 1962, with the publication of a study titled “50- to 100-Ton Payload Reusable Orbital Carrier.” Though previous studies had found that retrofitting the S-I stage of the Saturn I and IB with a flexible and deployable wing would be impractical, this study concluded that the much larger S-IC on the Saturn V had more room for improvement. This study envisioned an S-IC modified with landing gear, sharply-swept delta wings with large vertical tips, a flight deck, and modest thermal insulation to protect the booster from the heat of sub-orbital reentry. Boeing developed the design in more detail as the “Model 922,” studying several variants. In the most powerful of these, the Model 922 booster would be paired with an unmodified Saturn V second stage, retaining its full lifting power. This pairing, the Model 922-104, produced a booster that returned the first stage while losing only 20% of its lift capacity. Though these studies were not pursued in the early 1960s (all of NASA’s attention going to getting S-IC and the other parts of the Apollo-Saturn system flying at all), it did plant the first seeds of the flyback first stage in the minds of Marshall and Boeing engineers.

    In 1965, Congress began trimming NASA’s budget, which by that point had exceeded $5 billion per year. Smelling a coming storm on the wind, Marshall Space Flight Center and the prime contractors on the Saturn V (Boeing, North American, and Douglas) began studying lower-cost variants of the Saturn system, in order to keep it in service even in the face of future budget cuts. Boeing’s studies were the most wide-ranging, covering Saturn variants from the smallest (~20 tonnes to LEO) to the largest (over 200 tonnes to LEO) capacities. Of most interest to MSFC at the time, however, was Saturn INT-22, a combination of a winged S-IC with a reduced-cost S-IVB to yield a launch vehicle of 45 tonnes capability for a significantly lower cost per-launch than either the Saturn V or Saturn IB. A particularly revolutionary innovation in this study was the concept of “propellant ballasting.” By carrying more propellant than strictly necessary for lower-end payloads, and burning it off in a second post-staging burn of the first stage, reentry velocity could be reduced considerably for smaller payloads (like those needed to service a space station), extending stage life. Indeed, with sufficient ballasting, a payload of 25 tonnes could be delivered with such minimal heating on the booster that the existing aluminum skin of the S-IC would suffice for thermal protection. Though the INT-22 study did not become NASA’s official policy, it was favorably-enough received at MSFC to become the assumed baseline booster for post-Skylab space station programs, and featured prominently in Apollo Extension Series (later Apollo Applications Program) studies.

    One should not be fooled by the prominent wings on the INT-22 first stage—this vehicle was not a shuttle, or at least not The Shuttle as that term was understood by NASA in the late 1960s. Shuttle was supposed to be a complete break with the Apollo Program, a fully-reusable, two-stage-to-orbit system propelled by high-thrust staged-combustion hydrogen-burning rocket engines. Even at Boeing and Marshall, this understanding of the plan for the 1970s was inherent in their plans for INT-22—it was to be an interim solution, providing for early Space Stations until Shuttle came into service around 1977. The economic justification for putting wings on the S-IC assumed that the system would be phased out by 1980. When funding for a second run of Saturn components did not materialize by the end of the Johnson Administration, Boeing turned away from INT-22, and instead turned its focus to the two-stage Shuttle. The termination of the Apollo Applications Program and the shifting of focus at NASA from Space Stations to a reusable Space Shuttle in 1969 would have sent INT-22 to join NERVA, X-20, and Project Orion on the heap of space might-have-beens, were it not for a surprise decision by NASA in summer of 1970 to take a second-look at alternative Space Transportation System architectures.

    NASA’s Space Shuttle contracting process was divided into four Phases--A, B, C, and D. Phase A consisted of preliminary studies to determine the technical feasibility of an approach to the Shuttle problem. Phase B consisted of detailed studies and preliminary design, while C and D covered test articles and final development, respectively. NASA selected two companies to receive Phase B contracts in May, 1970, North American Rockwell and McDonnell-Douglas, deeming their proposals the strongest. Grumman Chairman Lew Evans, however, raised a massive complaint to Tom Paine’s office, strongly condemning NASA’s preferred Shuttle architecture and blaming Grumman’s loss on weak support from New York’s senators and accusing NASA of playing favorites with North American. Though he was unsuccessful in winning Grumman a Phase B contract at that time (and arguably contributed to the rift that had always existed between Grumman and NASA executives), Evans was persuasive enough, and Grumman’s proposal good enough, for NASA to finance studies of alternative Shuttle architectures. Grumman won the largest of these contracts, but lacked experience with large booster development, and so reached out to Boeing for a collaborative approach.

    The Grumman/Boeing proposal differed from the first successful Phase B contracts by incorporating disposable liquid hydrogen tanks. Working in close concert with Max Faget and his team at NASA, Grumman engineers under the direction of Tom Kelly proposed to use disposable, external hydrogen tanks to reduce the weight of the orbiter while at the same time increasing its delta-v capability. This allowed the booster to separate from the orbiter at a lower speed, reducing thermal loading on it and bringing the booster back into the flight regimes studied by Boeing for the INT-22 proposal years earlier. Grumman presented this modified Orbiter design at the Manned Spaceflight Center in Houston in November of 1970. By March of 1971, they had successfully persuaded NASA that their approach was the best, and the agency mandated that the previous Phase B winners, North American Rockwell and McDonnell-Douglas, redesign their Orbiters with external tankage. In May of 1971, working again with Max Faget, Grumman took the next logical step and moved the oxygen tanks out of the Orbiter as well, putting all the Orbiter’s propellant in a disposable, belly-slung aluminum tank. The Booster-Orbiter stack was now somewhat lopsided, as the orbiter hung off the side of the stack, but the numbers didn’t lie--it was as close as NASA had gotten to reaching the peak annual spending cap of $1 billion mandated by the Office of Management and Budget.

    Boeing’s management at the time was concerned about the company’s ability to survive the greatest aerospace recession since 1945. Between 1968 and 1971, ¾ of the commercial airplane sector of the company was laid off. These lay-offs rippled across the greater Seattle economy--suburban vacancy rates reached 40%, automobile dealerships collapsed for want of buyers, and so many people fled town that local U-Haul agencies ran out of moving equipment. Two real-estate men in Seattle put up a billboard near the airport, showing a lightbulb hanging on a wire, captioned “Will the last person leaving SEATTLE turn out the lights.” The Boeing 747 was not finding buyers fast enough to cover its development cost, and the US Senate was beginning to move against the Boeing 2707 Supersonic Transport; objections to noise and air pollution by the latter were finding sympathetic Senators in many states not tied to aerospace. The Shuttle became seen by some in Boeing management as critical to keeping the lights on.

    By moving the Shuttle Booster’s flight regime back into Boeing’s field of expertise, Grumman offered a way for both companies (for Grumman, too, was suffering from the strain of the F-14 Tomcat program) to save their own skins. By leveraging Grumman’s experience in manned spacecraft and Boeing’s experience in both large supersonic vehicles and large booster development, the two companies hoped to give NASA an unbeatable offer--a Shuttle system more conservative than the main Phase B studies, one easier to develop as it used more off-the-shelf technology, and yet one that still achieved all the payload-servicing, station-resupplying, satellite-deploying objectives NASA wanted in a package that was at least 90%-reusable. It was a match made, so to speak, in heaven, that would allow each company to keep the spacecraft and booster capabilities they’d so painstakingly built up over the past decade--or so it seemed.

    The honeymoon ended in late summer of 1971. The Reusable Booster, Reusable-but-with-drop-tanks Orbiter architecture got NASA closer than any other to the OMB’s funding cap--but it still peaked at $1.5 billion per year, half a billion dollars more than OMB would endorse. With the appointment of the new NASA Administrator, James Fletcher, the agency finally accepted that it could not develop the entire Shuttle system at once--the booster and orbiter would have to be developed in a phased development system, one at a time. Though Grumman and Boeing were researching very dissimilar products, they became competitors over scarce funding--NASA would either buy Grumman’s Orbiter, Boeing’s booster, or neither, but it certainly would not buy both at once.

    The Space Shuttle Decision, by August of 1971, was reaching its endgame. At this time, on the recommendation of President Nixon’s science advisor, Edward David, a new panel, chaired by Alexander Flax, President of the Pentagon think-tank, Institute for Defense Analysis, was convened to independently analyze the Space Shuttle program. During the summer and autumn of 1971, this panel would meet once a month, meeting with NASA and with the Shuttle contractors. It was during these months that Boeing and Grumman, Marshall Space Flight Center and the Manned Spaceflight Center, would make their own cases to the committee and seek approval for their own preferred option.
     
    Chapter 2: Rollout
  • The question, therefore, is, "is there a phasing of the shuttle or, alternatively, a cheaper shuttle that will not reach the very high expenditures in the middle of the decade?"


    Chapter 2: Rollout


    The rollout between the Booster Processing Facility and the Vehicle Assembly Building was not a high-profile event for any Lifter mission. For this phase of her preparation, Constitution was escorted by only a handful of photography enthusiasts with large tripod-mounted cameras, junior journalists from the Orlando Sentinel, the Huntsville Times, and the Houston Chronicle, and some of the engineers at Kennedy Space Center stepping out of work briefly to watch one of the world’s biggest flying machine drive by. Security guards kept them all at a safe distance as the airport tug pulled her south along the curving road to the VAB. Too wide for the doors at the end of the transfer aisle, Constitution was rolled in through the massive doors on the west side of the building. As the tug pushed the vehicle through a three-point turn to align the tail of the booster with the doors (only the widest, horizontally-opening portions currently open) the onlookers were presented a closeup view of the sides of the vehicle--generally clean, but yellowed and stained in some places from the heat of suborbital reentry. Her handful of admirers saw a vehicle that had already proven herself in tests and in operational missions.

    On the other side of the VAB, a narrower shape was being prepared for her own stacking. This one was much more familiar to the Apollo veterans who still made up a large share of the Kennedy Space Center workforce--an S-IVC stage, the stretched descendant of the S-IVBs which had sent men to the Moon. She’d been at the Cape for months, barged in with three identical sisters from California. Rolled in through the south entrance to the VAB, she was thoroughly checked out in preparation for her mission. Her J-2S-2 engine received particular attention, as it had not been test-fired after attachment to the stage--only before, as part of the lot of engines sold by Pratt & Whitney to McDonnell-Douglas. Unlike the RS-ICs, S-IVCs did not receive names, and any battle scars they earned were short-lived, as the stage ended its mission by burning up in the atmosphere over the Pacific or Indian oceans. This vehicle had never flown before.

    The third vehicle in the VAB was the most exotic of the three. Sleeker and smoother than the RS-IC, this last one had a black underside, a new tile-based thermal protection system to protect her from the greater thermal stresses of orbital reentry, and a set of Apollo- and Titan-heritage rocket engines on her rear for orbital maneuvers and, if the worst happened, to boost the crew to safety. As her larger cousin had years earlier when she’d first been unveiled, this one had a crowd of admirers eager to snap a picture with America’s newest spaceship. Engineers from both NASA and Rockwell who worked on her at the Cape were joined by busloads of tourists from the Visitor’s Center, bedecked in track jackets despite the Florida heat, though the latter generally remained behind a rope barrier to stay out of the former’s way. Polaroid camera flashes illuminated her from every angle as engineers and technicians checked her even more thoroughly than Constitution. Umbilical cables and air hoses (maintaining a constant positive pressure within the vehicle, to ensure that no contaminants entered) trailed from access panels all around the vehicle.

    Unlike the RS-ICs, whose tube-and-wing shape reflected their origins as disposable rocket stages, this vehicle, an Orbiter Vehicle, had a smoothly curving body, with no clear boundary between wing and fuselage--the entire body generated lift. Augmented by sharply-angled control surfaces, this lifting body design gave the spacecraft the atmospheric maneuverability to return to the US from any orbit at almost any time--which was why one of the other Orbiters, still in production at Downey, bore an Air Force star-and-bar instead of a NASA worm.


    The Flax Committee’s attempts to hammer out an affordable way forward for NASA must be considered against the backdrop of the budget situation for 1972. The OMB had proposed to reduce NASA’s budget to $2.8 billion for that year, which would have meant the reduction of piloted spaceflight to Apollo capsules on disposable boosters for the rest of the 1970s. Only the timely intervention of Caspar Weinberger and then President Nixon himself kept the budget at a relatively safe $3.3 billion. Before this happened, however, NASA Deputy Administrator George Low sketched out a proposal to replace the Apollo CSM with a manned, engine-less glider, which would have a small payload bay and significant cross-range, allowing it to service NASA space stations and pull off the single-orbit missions so interesting to elements of the USAF. Unfortunately, while far cheaper to develop, such a glider would have been reliant on disposable two-stage boosters, keeping its per-flight costs unacceptably high. The idea did not gain traction within NASA’s leadership, though elements of the Flax Committee were more receptive. NASA’s leadership switched focus back to the winged boosters and large orbiters favored at both Marshall and the Manned Spaceflight Center by this point.

    Both of these preferred options, however, came under fire as the Flax Committee systematically dismantled NASA’s entire economic rationale for the Space Shuttle. Even using NASA’s optimistic estimates of $5.5 million to $9 million per Shuttle flight and sixty flights per year (an estimate that one committee member said must have been made “on hemp”), the Committee concluded that the program would still cost the nation more than it saved. Many of the supposed savings came not from the direct savings in launch cost--which by themselves were barely equal to the task of paying off the tremendous development costs even at high flight rates--but instead from the benefits of less-specialized, less-compact, and heavier satellites and space probes which could be checked out in orbit instead of on the ground and use a standard set of structures and systems. However, while the studies depended on such “payload effects” to justify the massive sticker price of the fully reusable shuttle, companies buying or building payloads were less-enthused with the concepts.

    The Flax Committee took NASA to task on all these assumptions, criticizing the minimal projected startup costs and the speculative nature of the payload effects. By the time they were finished, the economic rationale for the Shuttle was dead in the water, but all was not lost. The Committee criticized both Mathematica and NASA for neglecting to study (or neglecting to publish) different phased development and interim operation schemes. The prime contractors had all suggested interim options in their reports to NASA and the committee, naturally giving their own preferred options primacy. Each of them offered the chance to reduce the non-recurring development costs of the program, even as the per-flight cost went up, but despite specific requests few had seen intense focus in the economic studies.

    Under pressure from the Flax Committee and Administrator Fletcher, NASA set out to rectify the issue. Mathematica Inc. studied different phased development programs in an effort to find one that gave NASA the capability it wanted while fitting under the OMB’s price cap. By October, the company released a new comparison with a much greater variety of options for NASA, ranging from the desired fully-reusable two-stage vehicles to Big Gemini on an uprated Titan III. The most promising candidates on the list, in the opinion of Deputy Administrator Low, were options called TAOS and ISRS.

    TAOS (Thrust-Augmented Orbiter System) called for a large Shuttle orbiter with a disposable propellant tank, its own engines, and either pressure-fed or solid rocket boosters, all of which ignited on the pad and fell off in flight. The vehicle was supposed to have a payload bay big enough for all NASA payloads, and for all commercial and military payloads on the drawing boards. It offered the benefit of a reusable spacecraft (in essence, a reusable upper stage) while putting the winged first stage off until the 1980s or even 1990s.

    ISRS (Interim Semi-Reusable System) was the exact opposite approach. Combining Boeing’s INT-22 study with Martin Marietta’s and Boeing’s glider studies, ISRS proposed a system with a flyback first stage built using Apollo heritage technology and a new, much smaller Orbiter designed for Space Station servicing. Its main disadvantage was the inability to recover large payloads--while TAOS could land with large and bulky recovered satellites, and recover payloads in the event of an abort, ISRS could not recover any but the smallest satellites, and any loss-of-mission meant a loss-of-payload. However, by keeping an existing liquid booster in production (albeit in a heavily modified form) while also calling for a new orbital spacecraft, ISRS satisfied more of NASA’s internal political concerns--Marshall Space Flight Center was pleased by building on the foundations they had laid during Apollo, while the Manned Spaceflight Center preferred the idea for keeping crew further from newly developed boosters than the TAOS side-mount concepts. NASA overall benefited from the absence of an expensive dedicated naval recovery force, as all components either burned up or flew back to the United States. Very importantly, the development cost of the winged S-IC was only half that of the TAOS orbiter (the glider’s development, drawing as it did on existing X-20, X-15, and lifting body research at NASA, was cheap enough that it fit comfortably into the difference).

    With the full two-stage system clearly unlikely to be approved, the fall of 1971 saw proponents for each system bombard NASA’s leadership and the Flax Committee with ever more detailed studies demonstrating the virtues of TAOS over ISRS and vice-versa. Gradually, committee members and administrators sympathetic to Big Gemini and Titan III or still stubbornly clinging to two-stage full-reusability came to one side or the other.

    The committee’s discussions ultimately came down to “intangible benefits” and room for growth in each architecture, as well as architecture cost. “Intangible benefits” refers to the research and operational experience value of the architecture--how much the architecture lays a foundation for future development. Despite all the economic analysis, it was still generally understood that the end-game of the Space Shuttle system was a fully-reusable vehicle with “airplane-like” operations that could perform a wide variety of tasks in space. The system that most directly contributed to that vision was held to have superior “intangible benefits.” In this regard, the full-sized TAOS orbiter and the smaller ISRS glider actually had roughly the same value--experiments with satellite servicing and payload bay operations could be performed as well in a 10’-by-20’ bay as a 15’-by-60’ bay, and hypersonic flight data from the smaller vehicle could probably be generalized to the larger one; the ISRS glider provided those same benefits at a fraction of the cost. For larger NASA and USAF cargo missions, the ISRS could be flown without the glider, and would in fact exceed the targets both for mass to orbit and payload envelope. The intangible benefit of recovering a satellite was deemed minimal, as the communications satellite industry itself had previously been found to be lukewarm to the idea. As far as intangibles went, TAOS could not deliver anything to justify its greater cost.

    As far as room for growth, ISRS could, at some point, replace its second stage with a fully-reusable Orbiter, as initially envisioned by NASA, while the first stage continued to see incremental development and improvement, eventually yielding the desired two-stage fully-reusable system. TAOS, by comparison, seemed a dead-end, and an expensive one at that. There was no way to make the system fully reusable without a complete rebuild, and to get to the point of partial-reusability, it required gigantic solid or pressure-fed boosters, advanced new cryogenic engines, advances in thermal protection, and a host of other innovations. ISRS, on the other hand, used off-the-shelf engines and operated mostly in a flight regime fairly well characterized by tests conducted with the X-15 in the early 1960s, and a size tested by the XB-70 shortly thereafter. For these reasons, the development cost of the ISRS was only half that of TAOS, while delivering the same per-mission cost savings and equal intangible benefits.

    Until this point, the President had been fairly divorced from discussions between NASA and the OMB regarding the details of the program and its required budgets, leaving it mostly to deputies like Fletcher and Weinberger to mediate the details. However, it became increasingly clear that without a direct presidential decision, the Flax Committee might be on the verge of rejecting any of these options or demanding yet more studies, which could in turn halt the momentum which had begun to build for the proposed program. The effects for NASA and for the aerospace industry could be cataclysmic, a fact which worried Nixon for two reasons. As already demonstrated, he had no interest in being remembered as the president who “cancelled the space program,” and had already been willing to step in to arrest the budget’s descent when it seemed it might imperil the operation of the agency’s manned space program. He wanted to give NASA a new grand vision all his own, though one on a budget. In addition, Nixon worried that further delays in the Space Shuttle program and the continued wind-down of Apollo could exacerbate job losses in an aerospace industry already reeling from the failure of the Lockheed L-1011 and the cancellations of the American Supersonic Transport program. With a mind set on taking some decisive action soon, Nixon waded into the details of the program personally in late November, after taking a week to digest the OMB’s summary report.

    In this summary report, following a detailed comparison of both systems presented by George Low, the Flax Committee finally ruled in favor of ISRS, with a small 10’ by 20’ payload bay for the glider. The decision to go with ISRS over TAOS was hotly debated, and there remains to this day a small but vocal community insisting that solid rocket boosters or pressure-fed rockets fished out of the ocean would be cheaper than refurbishing the 1950s-designed F-1, while a larger orbiter would have offered substantial benefit from having crew available to assist in satellite deployment. The budget projected for ISRS was within the OMB limits--if barely--and Nixon would be able to offer NASA both its booster and its orbiter. While they might not be the visions which NASA had originally developed, they would be indistinguishable to the public if sold carefully, and offered enough roles for centers and corporations in key states to address Nixon’s other concerns.

    This combined program won official presidential approval December 23rd, 1971, with the development of the booster to be included in the FY 1973 budget. The orbiter, whose design had evolved chaotically during the closing weeks of the debate over the design of the system, would require further study before it could be awarded, as would the upper stage which would complete the ISRS, but the program would shortly be on a firm footing to proceed. With the administrative details set, the program was officially rolled out to the public by President Nixon in an early January address from the White House.

    “I have decided today that the United States should proceed at once with the development of an entirely new type of space transportation system designed to help transform the space frontier of the 1970s into familiar territory, easily accessible for human endeavor in the 1980s and '90s.

    This system will center on two space vehicles. The first, the Space Lifter, will draw on the rich legacy of the Apollo program and will lift payloads to the very edge of space, with the journey to orbit and back completed by the Space Shuttle. These vehicles will revolutionize transportation into near space, by routinizing it. They will take the astronomical costs out of astronautics. In short, it will go a long way toward delivering the rich benefits of practical space utilization and the valuable spinoffs from space efforts into the daily lives of Americans and all people....

    Views of the earth from space have shown us how small and fragile our home planet truly is. We are learning the imperatives of universal brotherhood and global ecology-learning to think and act as guardians of one tiny blue and green island in the trackless oceans of the universe. This new program will give more people more access to the liberating perspectives of space....

    "The reason many people fail is not for lack of vision,” said the great American rocket pioneer Robert Goddard, “but for lack of resolve and resolve is born out of counting the cost." Let it never be said that the United States lacks the resolve to lead the world in the exploration and development of space.”


    Nixon’s staff had initially chosen the name “Space Clipper” for the program as a whole, with the individual components named “Uranus” (for the booster) and “Argo” (for the Orbiter). Nixon, however, was adamant that the point of the program was to open space to economic development--such poetic names were fine for the glory-seeking days of Mercury, Gemini, and Apollo, but the simpler, utilitarian names captured the everyday nature toward which the program aspired. The launch vehicle would be the “Space Lifter,” carrying the “Space Shuttle” for manned flights, with the two together being the parts of the “Space Transportation System.”

    With Nixon’s speech and Congress’s authorization of funding for Space Shuttle development, NASA and its prime contractors had crossed the Rubicon. They had committed themselves to the successful development of the Space Transportation System. Now “all” that remained was to define, design, build, and test the largest and fastest flying machines ever.
     
    Chapter 3: Assembly
  • “The goal we have set for ourselves is the reduction of the present costs of operating in space from the current figure of $1,000 a pound for a payload delivered in orbit by the Saturn V, down to a level of somewhere between $20 and $50 a pound. By so doing we can open up a whole new era of space exploration. Therefore, the challenge before this symposium and before all of us in the Air Force and NASA in the weeks and months ahead is to be sure that we can implement a system that is capable of doing just that.”


    Chapter 3: Assembly


    With the arrival of the Constitution in the Vehicle Assembly Building to join the already-present S-IVC stage and the Space Shuttle Endeavour, the pieces were in place for the first operational Space Shuttle mission. The only task remaining was to fit them into their proper places in the stack, integrating them into a single assembly to prepare them for flight. It was a familiar task for the VAB technicians, and they set to work with their typical care and skill. This particular stack drew particular interest from visiting tourists and NASA engineers alike, but the attention was nothing new to the team which had less than a decade before prepared Saturn V moon rockets in these very same spaces. Now, descendants of those famous craft were being readied for a mission much closer to home--but no less important for the future of NASA's space exploration ambitions.

    The assembly process began with the arrival of Crawler-Transporter 1, bearing on its back Mobile Launch Platform 3, which had been the first of the three MLPs to have its Launch Umbilical Tower modified to service the RS-IC Space Lifter. Under the eyes of a dozen directing technicians, the driver in the cab positioned the massive steel structure within High Bay 3, then gently lowered it onto the waiting support mounts. Technicians swarmed over the MLP, conducting the final checks of the hold-down mounts and service masts in preparation for the stacking process. Meanwhile, other technicians in High Bay 4, located across the transfer aisle on the west side of the building, worked around Constitution, still resting on her transport trailer beneath the five hundred foot ceiling. Not for much longer--the crews used the massive travelling cranes up in the rafters to position and mount two large yellow lifting fixtures to the nearly-747-sized vehicle. One mounted near the nose, just aft of the cockpit, supported by the new 325-ton crane added specifically for working with the RS-IC's bulk. The other, closer to the engines, was supported by the original Apollo-era 250-ton crane running on the same tracks. Technicians with torque wrenches worked their way around the lift fixtures, cross-checking the inch-thick mounting bolts for the fixtures. With that complete, the crews stepped back towards the walls, and while tourists looked on from the roped-off area in the transfer aisle, the overhead cranes took up the slack. Like a massive Harrier, the delta-winged booster lifted straight up off the transport rig--first a foot, then two, then ten, then thirty. With enough height, the two overhead crane operators almost 500 feet above worked a careful ballet at the direction of headset-wearing technicians on the ground. The 325 ton crane pulled in its lines, raising the RS-IC's nose as the 250-ton crane closed the distance between them, bringing the tail into line under the nose. Like a marionette on strings, the massive vehicle pirouetted and pointed its nose skywards, its wing-mounted tails clearing the floor by less than ten feet as its nose rose almost 200 feet into the air.

    With the vehicle lifted to the vertical, the two overhead cranes worked together, lifting the booster up by its own length, clearing the cross-bracing of the VAB structure at the 160 foot level and twisting it slightly around its axis to clear its wings through the gap into the transfer aisle. Engineers watched with technicians and yet more tourists as the booster--the size of the Statue of Liberty--crossed overhead beneath the two cranes, moving directly across the transfer aisle and into the the waiting High Bay 3, supported only by the thick cables--made thin by distance. More than a few let out careful breaths as the booster was lowered back to the level of the MLP deck, carefully aligned by technicians, then finally lowered onto the launch hold-down mounts and secured. The tension abated almost palpably as the MLP took up the weight. With the move done, the cranes and their fixtures were detached and work platforms were lowered into place around the booster. The cranes went to work on the next tasks, moving the far lighter S-IVC stage into the transfer aisle, lifting it to vertical, and handing it off to the large overhead crane. With the aft skirt and interstage which would protect its engine already attached, the S-IVC was lowered onto the mounting points on the nose of the RS-IC. As yet more work platforms were swung out to access the S-IVC, the cranes went back for the final pieces: the 30-ton Space Shuttle and its adapter. Once lifted into position, the Shuttle crowned a stack that was almost 300 feet tall. The final set of work platforms were rotated into place to access the Shuttle, and the engineers and technicians of the VAB crew set to work finishing the job of checking out the integrated vehicle. Four days after the arrival of Constitution in the VAB, the stack was assembled. Now it needed to be tested and readied for flight.



    With Presidential support secured for the Space Transportation System, NASA was able to line up several key trump cards behind the program, beginning in the oval office, moving down to supporters like Cap Weinberger at the Office of Management and Budget, and powerful Congressional interests from districts representing aerospace-heavy areas like California, Florida, Alabama, and Texas. It could also offer a vision for the future of space exploration directly endorsed by the President himself to follow the highwater marks of Apollo: a future where spaceflight might not be limited to the select group of military test pilots who in 1972 had so far landed on the moon, but scientists, doctors, blue-collar workers on space construction projects, teachers, reporters, and housewives. The vision of accomplishing missions in space in a cheaper, more cost effective way was a vision that was embraced to some extent by both space enthusiasts and space skeptics alike--though many of the latter still doubted if the savings of the vehicles depicted on paper could be achieved by vehicles built of metal. However, to see these plans tested, NASA would first have to move forward with translating these political successes into the reality of a new generation of manned spacecraft. The assembly of NASA’s centers and contractors behind the project and the division of responsibility for the vehicle began shortly after the President’s approval of the program.

    The distinction between the parts of the Space Transportation System offered a natural break between the spheres of influence of the agency’s most powerful centers: the Space Lifter was the obvious province of Marshall Spaceflight Center in Huntsville, while the Space Shuttle glider became with little challenge the preserve of the Manned Space Flight Center in Houston. As with Apollo, Marshall would provide the rocket, while Houston would supply the vehicle, crew, and carry out the missions. This wasn’t the only connection to Apollo, however. It was assumed within many of the studies supporting the ISRS architecture that the booster would be derived from existing stages and tooling, and the result was a rapid--and largely pro forma--Request for Proposal being issued February 21, 1972 with all proposals due two months later on April 21. Boeing, the foremost industry advocate for ISRS and originator of many of the key concepts with their involvement in the INT-22 design studies of similar vehicles in the mid-60s, unsurprisingly submitted one of the strongest proposals for the Space Lifter booster. However, a surprisingly strong second submission came from North American Rockwell, who proposed to draw on their history with the X-15 (described in their proposal as the “first reusable suborbital rocketplane”) and the XB-70 Valkyrie Mach 3 bomber in the development of a Space Lifter derived not from the Saturn V first stage, but from its second stage, using the same ballasted, retro-boosting hot structure approach applied to the S-II stage that Boeing suggested to apply to the S-IC. However, NAR’s proposal was weaker in several areas, particularly development cost: the J-2 engines of the S-II would need to be replaced with new high-pressure engines like the proposed SSME, the VAB and MLPs would need to be more heavily modified to mount to the S-II at zero level, and other changes would cascade through the architecture. Thus, though North American’s proposal was rated quite highly, the contract was awarded in May to Boeing. Marshall and Boeing immediately set to work fleshing out the details of the design and arranging the evaluation of S-IC tooling which had been preserved since the end of the first run of Saturn V rockets two years before.

    Despite the unexpectedly strong challenge from North American, Boeing’s design for the Space Lifter was similar in broad strokes to their previous designs for reusable S-ICs, ranging back to the earliest 1962 Marshall studies: a broad delta wing grafted to the side of a fuselage derived from the existing 10-meter S-IC tanks, with a cockpit and nose in the front and a set of airbreathing engines below the wing around the middle, near the intertank between the kerosene and liquid oxygen tanks. However, the design now needed to address aspects which had been left as “details for later study” in its earlier ancestors. Would the landing engines use feed lines to a new side-located sump in the kerosene tank, or were smaller “ferry” tanks just for flyback prefered to minimize the risk of slosh within nearly-dry fuel tanks? How would the VAB, Michoud, and other facilities be able to handle the large rudders necessary for the aerodynamic control of the booster? A variant of the F-101 engine was selected for the airbreathing propulsion system, but the manufacturer, General Electric, would have to do additional tests on how the engines would be started during a supersonic glide as the booster exited the hypersonic portions of its return to Earth. Although Rocketdyne had already designed the F-1 engine for up to 20 starts and an operating time of up to 2250 seconds between major overhauls, part of requirements to enable the initial proving tests back in the late 50s, the Lifter would require two starts on its engines in every mission: once at liftoff, the other above the atmosphere to slow the vehicle for entry. This air start had to be completely reliable--without it, the vehicle’s structure would be incapable of surviving entry in a condition to be reused. A new variant, the F-1B, was commissioned from Rocketdyne to enable this use.

    The design of the crew cabin and nose posed additional challenges. The Space Lifter design called for the assured ability to get the Lifter’s flight crew away from the stack in the event of any abort before separation. Thus, the vehicle needed not just a cockpit, but an entire ejectable flight deck--a separate spacecraft capable of independently surviving atmospheric entry at an un-slowed speed, then ditching in the ocean and staying afloat while rescue crews arrived at the site. With most of Boeing’s efforts focused on the broader vehicle, the company decided to subcontract the design of the abort capsule, and thus of the flight deck of the vehicle. In 1973, Boeing gave the contract to the same Grumman team they had worked with during the initial Phase B Shuttle studies, then opposed in the TAOS/ISRS configuration debate just a year later. Friends and enemies changed quickly in the military-industrial complex, and Grumman’s work on their entry for the glider competition gave useful grounds for the work on the design of the abort capsule and flight deck. Below the flight deck and forward of the liquid oxygen tank was another major feature which would go on to inspire serious concerns: the vehicle’s nose structure. Boeing’s original concepts called for the “point” of the booster’s nose to slide backwards prior to integration, creating a space for the upper stage engine to be stored prior to separation. This would enable the upper stage to mount directly to the forward structure of the booster and eliminate a need for a disposable interstage fairing. For return flight, the nose would extend and lock, covering the gap for atmospheric entry. At the time, it was anticipated to be complex, but not more of a problem than any other part of the RS-IC.

    With the specifics of the booster laid out, Marshall focused on fleshing out the other portion of the Space Lifter design: the expendable stage which would complete the ascent to orbit and deliver the payload, whether that be Shuttle or a satellite. The design of the upper stage was bounded by the capabilities of the booster, but the responses received following the June 1972 Request for Proposal included a variety of specific approaches. The final selection converged on two top designs. The first, from McDonnell-Douglas, was a stretched “Chinese copy” of their S-IVB stage: a lengthened stage incorporating many changes to enable higher-rate production at lower cost. Building on their own work during Saturn cost reduction studies, McDonnell estimated that they could produce the stages for roughly half the cost of their S-IVB while drawing extensively on the existing production, handling, and checkout facilities created for Apollo. The design also called for a slight modification to the J-2S engines developed for the S-IVB, giving them a nozzle with an 84:1 area ratio rather than the stock 40:1, to increase vacuum specific impulse from 436 seconds to 451, the Isp targeted by the Space Shuttle Main Engine. The second, from Convair, was a an oversized “balloon tank” design, similar to the design of their Centaur upper stage though scaled up dramatically in every dimension. The result would be a fantastically high-performance stage, particularly if fitting with a cluster of up to ten RL-10s instead of the lower-performing (without the nozzle extension) J-2S. The Convair proposal was scored highly on their grasp on technical issues and their studies of low-cost production: the study included many pages detailing how their stage could be built using cheap rolling techniques, the low costs Pratt & Whitney was willing to project for the required numbers of RL-10s, and drawing on their Atlas missile experience to explain how production of 70 or more stages per year could be economically supported. In the end, the deciding factor was initial design cost, as it had been with Marshall’s selection of the RS-IC.

    As the year had worn on, it had become apparent that Johnson was running behind and that the design of the glider might prove more expensive than had been projected originally. If any Shuttle was to actually carry astronauts to space, Marshall would have to economize its development to cover Johnson’s overruns--even if this meant elevated recurring costs in the future. Among much grumbling from Marshall’s management, who resented being handicapped in their work to assist another center which was unable to manage its area of responsibility, cost was ranked higher in the selection criteria, and McDonnell’s S-IVC lept to the top of the list. With Marshall’s existing relationship with McDonnell on the S-IVB, it wasn’t an undesirable result, but Johnson’s overruns remained a point of contention between Marshall and Johnson as the program developed.

    The Space Lifter upper stage wasn’t the only project to suffer as the decisions on the design of the glider dragged on and questions about budget were raised, and the consequences to other programs were more permanent. Only a few years before in 1969, the nuclear thermal engine NERVA had beckoned to open up the planets, while Pratt and Rocketdyne had competed for the prize of the high-pressure, high-thrust, long-life Space Shuttle Main Engine--a staged-combustion hydrogen-oxygen engine with a chamber pressure three times that of the modern F-1B. This SSME was to have been used on both stages of the early and fully reusable Space Shuttle designs. With the selection of Boeing’s RS-IC booster over North American Rockwell’s RS-II and the use of the expendable J-2S-2 on McDonnell’s S-IVC upper stage, the SSME was a very expensive project without a purpose, just like NERVA had become. Both of NASA’s new high-technology engines were targeted for elimination, in spite of protests from engineers involved and congressional representatives from the districts affected. Rocketdyne was partially compensated for the cancellation of SSME with their contract for the F-1B, but many planners felt as though the quest of NASA for ever-more-advanced technology had ended: the engines for the Space Lifter would be bound firmly within the 50s-era past, not the advances of the future.

    The issues with the budget may have been encountered primarily by the Manned Space Flight Center and their work on the glider, but the root of the issue came directly from the original Shuttle Decision and announcement. While the ISRS program had already studied many details on the specific booster and upper stage requirements, meaning Marshall was working towards a very well-defined vehicle, the glider had emerged from the Flax Committee recommendations barely more than some rough conceptual numbers on a blank sheet of paper: a 45,000 pound dry-weight vehicle with capacity for six to eight crew and up to 10,000 pound payload in a 10 foot by 20 foot payload bay. It was a rough enough set of specifications that every major group within NASA could project their preferred designs for the Shuttle onto them, and the result was that the process of preparing the Request for Proposal for the orbiter design was lively at best, and completely chaotic at worst. Maxime Faget once again raised the question if cross-range was still a critical requirement, and thus if his preferred (and patented) straight wings could be used instead of the delta wings which had emerged as the preferred option for both the booster and the TAOS orbiters. The glider design group also reexamined the choice of tiles versus hot structures for the glider's thermal protection. With such core questions reopened, configuration questions and studies abounded. The Manned Space Flight Center was quickly swamped with alternative designs as they worked to focus on a single design for the final Request for Proposal as groups took a last opportunity to pitch the advantages of their designs. The most emblematic of this came with a final attempt by McDonnell to pitch a variant of their Big Gemini: if the glider only needed to reach orbit and return, why couldn't a capsule with internal payload bay serve just as well?

    It took almost six months to once again review and retire these resurgent, previously abandoned designs. The Shuttle still needed to have cross range for polar orbit and for a greater number of landing opportunities, which straight wings like Faget’s orbiter couldn’t achieve. However, there were concerns about the high peak heating which might be experienced on the leading edges of a delta-winged orbiter headed to space, and on the volumetric efficiency of such a design for the smaller glider. Advocates of the delta wing and straight wing orbiter reached loggerheads, which left an opening for a compromise neither liked. Lifting bodies, with small aerodynamic surfaces providing control for a vehicle whose fuselage provided most of the lift, had been extensively studied by NASA and the USAF at Edwards Air Force Base. These early tests of the X-24 demonstrated the advantages of such a design for a small but maneuverable entry vehicle. Several of the studied designs could achieve the cross range required by the Air Force for single-orbit polar missions, but the blunter bodies offered more volume and lower overall heating than the thin leading edges of a delta wing. The debate went in circles for weeks, then months, and the delays lead Administrator Fletcher and others familiar with OMB and Congress to worry that if Shuttle didn't get moving, it might put the entire Space Transportation System in jeopardy. The pressure came down on high in a series of meetings with the design leadership. In one legendary (and possibly apocryphal) story, a NASA manager began one of these meetings by upending a briefcase full of various contractor models onto the conference table, sending lifting bodies, delta-wings, straight-wings, and capsules scattering across the tabletop. “Do we want to keep building these? Because if we do, we’re not getting the money for the real one,” he supposedly continued. Whether the incident is true or not, the message from Fletcher on down was clear: if NASA was going to have an orbiter at all, they needed to get moving. The final design settled on the lifting body, offering a design with the volume for a larger crew cabin and payload bay, and the cross-range required for USAF missions. Orbital maneuvering propellant and other systems could be packed into oddly-shaped spaces within the structure which wouldn’t have fit the propellant tanks of an orbiter with its own propulsion. A grudging agreement was secured on these points, and the lifting body emerged as the selected architecture.

    Even after the Lifting Body architecture was settled upon, debate raged about the exact capabilities of the eventual Orbiter, most particularly with regard to its propulsion systems. The Orbiter initially called for two jet engines, to be used in the last phase of flight for assistance in landing and giving the crew the ability to go around for another pass if the first approach did not seem feasible. Deke Slayton, at the Astronaut Office, insisted on these engines for a long time, despite protests from lifting body test pilots from Edwards AFB that they were totally unnecessary, as demonstrated by hundreds of unpowered landings at that base. Slayton countered that, after an extended time in orbit, the astronauts would be out-of-practice at actual piloting, unlike the Edwards pilots, who trained in the simulator up to the day of their actual flights. Even after the RFP was published, the debate raged, and not until late 1972 did the requirement for jet propulsion disappear, as the impact on Orbiter payload (a full 25% reduction from 8 tons to 6) ultimately trumped Slayton’s caution.

    Further debate centered on the Launch Abort System. In a break from Apollo and building on the precedent of Gemini, the Orbiter was to be equipped only with ejection seats, and these only for the first few missions. The system was to be built safe enough that an abort tower would be unnecessary. This decision was criticized from numerous corners, particularly from the astronaut office, but statistical analysis indicated that an abort tower would only be useful in a handful of abort scenarios anyway. This did not stop Thiokol and other solid rocket motor manufacturing companies from lobbying to reverse the decision in any way possible--up to and including going over Administrator Fletcher’s head to the President of the Church of Jesus Christ of Latter-Day Saints, who met his coreligionist and tried to persuade him to direct some work to Utah. Somewhat angrily, Fletcher responded that any decision he made would be in the interests of the US government and NASA first, and Thiokol last.

    Ultimately, engineers at Martin-Marietta hit on a compromise that allowed abort capability without unduly driving up per-mission costs or reducing Orbiter payload too badly. In order to accomplish all the missions intended for it, the Orbiter had to be able to maneuver in orbit, to the tune of at least 300 m/s of delta-v. This required a storable propellant engine and sizeable propellant tanks. Drawing on their experience with the Titan II upper stage, which NASA had trusted to lift Gemini crews to orbit without redundancy, they proposed an Integrated Launch Abort and Maneuvering System, using the same propellant for orbital adjustments and for launch abort, as no mission could conceivably involve both operations. In November 1973, NASA adjusted the requirements for the Orbiter to feature just such a system, with one AJ-10 for orbital maneuvering and four of the Titan-legacy LR-91 engines for abort thrust, tackling the problems of maneuvering and abort with the same system. With the Shuttle configuration finally largely decided, Houston was able to push a Request for Proposal out the door just before the close of 1972.

    North American Rockwell, who had so far been unable to secure any work on the Space Lifter, devoted substantial effort to their Shuttle proposal, and their experience with the X-15, Valkyrie, and Apollo programs served them well in preparing one of the top two responses. For additional experience in the design of lifting body vehicles, NAR partnered in their proposal with Martin, who brought extensive experience with the type, and which had won support in NASA by proposing the ILAMS system. The strongest competition in technical scoring came from Grumman, who joined with Northrop on the design of their Shuttle. However, while Grumman's design was ranked well in technical aspects, including the lowest dry weight of any entrant, its proposed system designs were criticized as excessively complex and there were concerns expressed about the company's shaky financial footing. It certainly did not help Grumman’s case that Willard Rockwell and other members of the North American and Rockwell leaderships had been donors to the Republican Party in general and President Nixon in particular since the 1950s. Whether or not corruption was involved, the result was that in March 1973, the NAR proposal was officially selected. However, Grumman was able to secure a major consolation prize: Boeing accepted a proposal from them for the subcontract on the Space Lifter's cockpit abort pod.

    The Orbiter, as finally proposed by North American and Martin, was based on an enlarged Martin X-24A lifting body, whose blunt nose was deemed less vulnerable to heating at hypersonic speeds than the pointed nose of the X-24B, with facilities for six crew (though, in practice, it was not supposed to fly with that many occupants except for very short space station crew rotation flights). The use of conduction- and liquid-coolant-based heat rejection made it possible to operate the spacecraft at an internal pressure of either 14.7 oxygen-nitrogen or 5 psi pure oxygen, depending on mission requirements. The payload bay was wedged in front of the vertical stabilizer, 10 feet by 20 feet, just big enough for small satellites or other test payloads. A small airlock and docking system, based on the Docking Module in development for the Apollo-Soyuz Test Project, was designed to mount at the forward end of the bay, tied into the cabin for missions which would require docking or EVA.

    With the prime contractors for the Space Lifter, its upper stage, and the Space Shuttle orbiter decided, 1973 found a veritable army of engineers setting to work on the components of the Space Transportation System. Marshall had already been serving as the hub of feverish work surrounding the RS-IC booster and the S-IVC upper stage; now the newly-renamed Johnson Space Center became the center of their own new web of contractors and subcontractors as North American Rockwell dug into the task of turning their Space Shuttle design into a flying vehicle within five years.

    With the design of the vehicle taking shape, studies also began at Kennedy Space Center on how the vehicles would be handled, assembled, and launched. Some study was given to launching the Space Transportation System from other sites, ranging up and down the eastern seaboard and the west coast in search of cheap and functional sites for equatorial and polar launches. Senator Clinton Anderson from New Mexico repeatedly attempted to influence a decision in favor of a new joint polar and equatorial launch site located at White Sands: flights of the Lifter downrange to the east for equatorial flights and to the north for polar flights would overfly one of his state's most plentiful resources: underpopulated land. Thus, some studies suggested, it would be easier to land the Space Lifter down range with less fuel for the Lifter's air-breathing jets. After landing down range, the Lifter could refuel and and work its way back to the launch site via a series of commercial and Strategic Air Command airstrips. However, while alternate launch sites received extensive lobbying focus, they were quickly revealed as the fantasies they were, given the substantial infrastructure that existing sites already possessed. In particular, given the significant heritage that the Space Lifter would share with the Saturn V and existing infrastructure at KSC, the Cape was rapidly confirmed as the site for equatorial launches. Vandenberg Air Force Base in California was selected as the polar launch site, with the Space Lifter to join the rockets it might someday replace.

    With the inevitable confirmed, work began on laying out changes which would be required to the Mobile Launch Platforms, Mobile Servicing Tower, Vehicle Assembly Building, and other infrastructure around Cape Canaveral. As Boeing's plans for the Lifter firmed up in 1974, ground was broken on a set of large hangars and servicing facilities for the new boosters, while across the road another survey party took measurements to lay out the location of a smaller set for the maintenance of the Orbiters. Kennedy was still planned to see the launch of one final Saturn IB and Apollo for the Apollo-Soyuz Test Project, but NASA's most famous launch site--along with the rest of the agency--was already actively working towards their next challenge. The politics and contracts were complete and the teams had been assembled. However, the challenge of getting from a designs on paper to a vehicle on the pad still remained to be met.
     
    Interlude: Technical Specifications
  • L5 Society Lobbying Brochure, “The Space Transportation System: A Wagon Train to the High Frontier”--1975

    “The Space Transportation System is, therefore, crucial to ensuring the competitiveness of the United States in space exploitation. Its launch cost, at $18.6 Million (1971 dollars--see attached breakdown), is an order-of-magnitude reduction from the costs of the Saturn V, while still retaining the ability to launch almost half the total payload. By reusing the largest single part of the vehicle, the Space Transportation System eliminates the costly task of building an entire new vehicle after every flight, and opens up new possibilities for economic development of the high frontier.”

    Cost per Launch Breakdown (planned in 1971):

    Lifter $6.4 Million
    Interstage $1 Million
    S-IVC $7.9 Million

    Propellant $0.3 Million
    Labor* $3 Million
    Total: $18.6 Million

    *: Labor costs are the cost of the STS support workforce amortized over 20 launches per year.


    Revell-Monogram Educational Booklet “America’s Space Truck: The Space Transportation System,” released with “Space Transportation System” model kit, 1977, 1:144 scale.

    Though it will operates more like an airplane than previous rockets did, the Space Lifter, like all rockets, will be mostly fuel and oxidizer at launch. On the pad, the Space Lifter Constitution will weigh 5,342,140 pounds, but when its wheel stop at landing, it will weigh only 600,000 lb. The S-IVC Upper Stage, which will be disposed of at the end of every mission, will be even lighter compared to its fuel load--50,000 lb dry to 450,000 lb wet. The Space Shuttle carries only the fuel it needs to maneuver on-orbit: its weight is 91,270 lb wet, 72,140 lb dry, of which 17,600 lb is the Shuttle’s payload.
     
    Chapter 4: Crawling
  • “One thing Skylab taught is that we should glance back from time to time to avoid old mistakes and gain inspiration from old successes. But to move forward into the future, we don’t need to revive the past.”


    Chapter 4: Crawling


    Bathed in the light of a dozen xenon arc lamps, MLP-3, bearing atop it the Launch Umbilical Tower and the 30-story-tall Shuttle stack, began its journey out to the launch pad hours before dawn. Engineers and technicians walked with it out to the pad, easily matching the ponderous pace of the nearly 8,000 tonne stack. Smoky diesel exhaust trailed out of the Crawler’s vents, as the four 1 MW engines labored to drive the massive tracks that distributed the vehicle’s weight across the sandy crawlerway and kept it from sinking into the soft Florida soil. It was a routine that the engineers had practiced many times on earlier flights, and on Apollo and Skylab before them, and planned to practice many times again. But, given the payload of this flight, there was understandably more attention to detail—not one nut out of place that anyone on the ground could see.

    Hours passed. The sun’s light reached over the horizon, reflecting off the undersides of distant clouds to cast orange light onto the Vehicle Assembly Building and then the stack. Then, like a rocket engine reaching full thrust, the sun itself crossed the horizon, and the light of the xenon lamps was drowned in a much brighter glare.

    At last, shortly after dawn, the stack reached LC-39A, and the crawler deposited the 5,000-tonne pad, tower, and vehicle combination on the raised concrete foundation. Then it drove back to the VAB—its job was not yet done, for there was still the Mobile Servicing Structure to bring over, the tall gray tower whose platforms gave technicians access to the vehicle as it stood on the pad. Another hour and a half to drive back to the MSS, another hour and a half to bring it over to LC-39A. By the time the crawler’s job was done, dawn had given way to a beautiful Florida morning.

    Launch was still several days off—now came the time for final check-out, as each spacecraft component was put through its last ground tests. Telemetry was checked, temperatures on major components were inspected, radio tests were performed, and technicians made last-minute inspections inside the cockpits of each vehicle to make sure nothing had changed between stacking and arrival at the pad.

    An alarm went off—the fill test of the S-IVC had revealed a leaky hydrogen line in the interstage. There was a buildup of hydrogen gas in the interstage—dangerous enough on its own, but in close proximity to two oxygen tanks, it was worse. The test was terminated immediately, the tanks given time to vent, and technicians opened access panels around the base of the stage to inspect. Could the lines be repaired on-site? That was the preferred option—rolling back to the VAB was a time-consuming nuisance. But if the problem was severe enough, the vehicle would have to be de-stacked, and the stage either repaired or—heaven forbid! thought the launch operations director—replaced with a new S-IVC, costing even more time.

    Luckily, the McDonnell-Douglas technicians were able to isolate the problem and correct it. The test was repeated less than a day later, with no apparent hydrogen build-up. The tests continued, each system checked out properly, and the launch operations director allowed himself the luxury of optimism—perhaps this first mission of the Shuttle would go off on-time!

    Alas, a new issue came up, one which all the technicians at the Cape were powerless to solve. NOAA and the USAF both warned about a line of severe thunderstorms crossing Florida. In normal circumstances, the stack would have remained on the pad—the lightning rods surrounding it would protect it from electrical disturbances, and the Booster was durable enough to take a little hail. But the Orbiter, with its exposed tile thermal protection, was an unknown variable. Putting it at risk to save a few days was out of the question—the director reluctantly ordered a full rollback to the safety of the cavernous VAB.

    At times like this, he thought as he finished his morning coffee while monitoring the rollback, he regretted that White Sands had not been chosen as the main Shuttle launch site.

    When the storms cleared, the dance of the lumbering giants was repeated, and the Space Shuttle stack finally occupied the pad again on July 21, 1980.



    As each of the major STS contracts was assigned, the prime contractors began the monumental task of developing and testing a reusable spacecraft system. Though not quite as complex and uncharted a task as the Apollo program, the Space Transportation System gave its contractors and program heads a great deal of grief before its first operational flights. The process began in 1972, with the awarding of the contracts for the Booster and Interim Upper Stage vehicles. These were the best-characterized of the three main STS components, and so metal-cutting could begin on them long before the Orbiter was ready.

    The S-IVC was the most straightforward component. During the selection process for the Space Lifter upper stage, Douglas had proposed a number of changes to the S-IVB much more extreme than a simple stretch. Some of these changes, like the shift from internal tile-based insulation to external spray-on insulation, stemmed from the experience acquired by the American aerospace industry by building three different stages that used cryogenic hydrogen for Project Apollo. Each of the three different cryogenic stages developed in the 1960s--Centaur, S-II, and S-IV/S-IVB--used wildly different construction techniques. Centaur was a pressure-stabilized stainless steel balloon--without constant pressurization, the stage would collapse under its own weight (as the closely-related Atlas stage collapsed during preparation for the launch of Mariner 6 in 1969), with four external insulation panels and two RL-10 engines. S-II and S-IVB used much more conventional construction techniques, at the cost of greater weight, and used the much more potent J-2 engines. The S-IVB stage used a complicated system of custom-made tiles to insulate its liquid hydrogen tank, which had to be applied to the inside of the tank in a time-consuming process. The S-II had originally been designed to use a honeycomb-panel insulation system, with large sections of insulation secured to the outer surface, but the extreme cold of cryogenic hydrogen had a tendency to liquefy air pockets trapped between the insulation and the rocket, weakening the bond and causing panels to fall loose. The helium-based purge system North American introduced never worked very well, and, starting with the S-II stage for Apollo 13, the company shifted to a spray-on insulation that eliminated bonding agents and air pockets entirely.

    Douglas’s engineers were very well-aware of these changes even as the Apollo program wound down, and incorporated many of the design innovations from S-II and Centaur into their proposals for S-IVC. The intricate tile-based insulation would be thrown out in favor of spray-on foam, and control software developed for Centaur to enable navigation in less-than-ideal weather would be adapted to the Saturn Instrument Unit. The loss of J-2 engines on two separate Saturn V launches led them to propose the addition of a second J-2S-2 on the S-IVC, producing a stage that came to resemble a gigantic Centaur. Though they (and Rocketdyne) argued vigorously that the second engine on each stage increased redundancy while also offering economies of scale in engine production, NASA’s focus on mission costs led to the S-IVC proposal scaling back to one J-2S-2 per stage. Thus, the final S-IVC involved little of the originally planned new technologies. Even its upgraded J-2S engine, with the exception of the proposed new nozzle, had already seen the test stand before the end of the Apollo program in December of 1972. Its challenges were more in the field of logistics and cost-control. McDonnell-Douglas worked diligently to implement the cost-cutting measures of the “Chinese Copy” plan, reducing handling and increasing automation. Though it lacked the missile-manufacturing experience of rivals like Martin Marietta and Convair, McDonnell-Douglas adapted several automation techniques used in its airliner business to the S-IVC, more-or-less achieving the manufacturing cost savings it had planned for. After some internal argument, the company elected to mothball its own Sacramento test site rather than upgrade it to handle the S-IVC, and trust in Rocketdyne to supply functional J-2S-2 engines. Test-firings of the fully-assembled S-IVC would be performed only at Stennis Space Center.

    A greater headache was actually transporting the stage from Huntington Beach, California to Cape Canaveral. The S-IVC’s stretched length left it too long to fit inside any of the Guppy-derived aircraft NASA had preferred for S-IVB delivery. Though Douglas had barged some S-IVBs in the 1960s, they did not relish the long travel times that that approach required. Furthermore, in recognition of the fact that Shuttle was supposed to fly at least a dozen times per year, it was necessary to be able to have S-IVC stages ready to mount on a Space Lifter at any time, in case there was some anomaly that required swapping-out stages, or a time-critical emergency payload. McDonnell-Douglas and NASA ultimately invested in a new, larger barge, which could carry four S-IVC stages at a time through the Panama Canal or to Vandenburg Air Force Base, allowing either launch site to maintain a surplus of upper stages at any time. The first S-IVC test stage was fired in 1977 at Stennis Space Center, and was then sent on to Marshall Space Flight Center for storage in case it was required for an accident investigation.

    The Space Lifter was the single largest and heaviest component of the Space Transportation System, and the one with the strictest reliability requirements. Unlike the Orbiter, which would fly only a fraction of the total STS missions, and the S-IVC, which did not always carry a crew, the Space Lifter had to succeed at its goal for both mission success and astronaut survival. NASA thus required an extensive testing program, including piloted abort missions and one destructive test to verify the operation of the escape pod. In order to streamline development and get to flight-testing sooner, Boeing engineers at Marshall Space Flight Center converted several remaining S-IC test articles into RS-IC test articles, retrofitting them with wings, landing gear, and (initially) dummy flight decks. The first prototype (RS-IC-F), formerly the fit-test S-IC that debuted at Cape Canaveral in 1966, was retrofitted at Marshall and rolled out of its hangar there in June of 1975, rolling down to the Tennessee River for barging down to Stennis Space Center and on to Kennedy and Vandenburg for fit-tests. This one lacked a functional flight deck, but conveyed the overall dimensions of the vehicle well enough for that task.

    1974 saw the first major redesign to the Space Lifter--the elimination of the retracting nose and addition of a disposable shroud between the Booster and the upper stage. In the near-hypersonic flight regime of the Space Lifter during descent, a failure of the nose to extend would lead to catastrophic stagnation of airflow in the confined area of the nose--which would cause immense heating in the unshielded interior of the spacecraft. Computational Fluid Dynamics testing, performed on the finest computers available at the time painted (metaphorically--graphical outputs were beyond their capabilities) a grim picture, with loss-of-vehicle in almost every failed retraction scenario. Boeing could not guarantee a failure-proof hydraulic or spring-loaded extension mechanism, and so opted for a triple-redundant pyrotechnic bolt to jettison a traditional interstage over a smooth, fixed nose. The cavernous volume of the Space Lifter’s nose would vex Boeing engineers for years after this decision--it cried out for utilization, for extra propellant tanks or other efficient use, but issues with mass distribution and changes of mass in flight precluded that. It fell to an enterprising young woman with NASA’s Education Office to propose the Student Suborbital Experiment Bay, which has carried hundreds of experiments from High School and University students past the Karman Line and exposed them to microgravity for several minutes at a time.

    The first Booster actually destined for flight, RS-IC-601, actually rolled off the assembly line on June 17, 1976. RS-IC-601 went on a cross-country tour at the end of June, visiting several major civilian airports, culminating in a landing at Washington National Airport on July 4, where, in celebration of the American Bicentennial, President Ford christened her “Independence.” Still without functional rocket engines (indeed, still without quite a few of the systems that would get her ready for suborbital flight), she was put through a subsonic and then low-supersonic flight-test program to verify low-speed handling and the ability of the spacecraft to successfully navigate to a landing. Ken Mattingly, who commanded the Atmospheric Test Flights, had few kind things to say about the vehicle’s performance--”It’s like flying a brick,” he complained. But it did the job it had to do.

    While all seemed well with the Booster, the Orbiter’s comparatively advanced technologies, particularly the lifting-body shape and tile-based thermal protection system, gave North American’s engineers no end of headaches. By the end of 1976, it had become apparent that the Orbiter would not be ready in time for its planned 1978 debut. As NASA prepared for the imminent change in administrations, this was very unwelcome news, but would have been a mere nuisance were it not for the publication, in 1977, by NOAA of solar activity predictions that predicted severe heating in the upper atmosphere. NORAD quickly followed up with a prediction that the Skylab space station, which had been quiescent in orbit since 1973, would reenter, not in 1981 as expected, but in 1979.

    NASA had planned to reboost Skylab with an early Shuttle mission, to test out the rendezvous and docking capability of the Orbiter, to demonstrate attachment of the Reboost Module from the payload bay to Skylab’s docking port, and to obtain samples of a vehicle left in space for over half a decade. But between the delays on the Orbiter and the imminent demise of Skylab, these plans seemed to be going down in flames.

    1977 thus saw a frenzy of mission planning at every major NASA center, as options were evaluated for saving Skylab by somehow advancing the Space Transportation System’s schedule. These ranged from the semi-plausible (reconfiguring one of the launch pads at Cape Canaveral to fly a Saturn IB/Apollo spacecraft, which by this point would have to be taken back from the museums to which they’d been handed) to the uncertainly safe (flying Space Lifter with an Apollo spacecraft as a payload, without going through NASA’s planned suborbital and abort test regime) to the expensive (flying a Space Lifter unmanned as in a conventional Saturn V mission, with an Apollo payload and dumping the booster into the ocean) to the downright bizarre (one proposal suggested using surplus Gemini spacecraft launched off a Titan II pad to reboost Skylab). There also emerged at this time a proposal to launch Skylab B, which had been handed over to the National Air and Space Museum but not yet fully “decommissioned” for museum display, but this proposal was perhaps the most expensive of all.

    Ultimately, budget overruns on the Orbiter and lack of attention from President Carter meant that each of these proposals was simply more expensive than Skylab, decrepit and aged, was deemed to be worth. NASA planners expected that, once both were flying, development funds could be spent on a more mature Skylab follow-on, one that would meet the desires of the Apollo Applications Program planners in the late 1960s (memoranda circulated at Ames Research Center, for example, proposed modifying an S-IVC into a tumbling artificial gravity experiment--long a goal of the 1960s). When measured against the need to make sure Shuttle was completed and the possibilities the 1980s yet held, Skylab was found wanting. All the same, the loss of a station that still seemed, to many researchers, perfectly viable left a bad taste in many mouths, and contributed to an unnecessary amount of bureaucratic infighting over the experimental Space Stations of the 1980s.

    1977 came and went without funds for Skylab. As that year progressed, Independence was outfitted with more equipment necessary for flight testing, and her sister ship, RS-IC-602 Constitution joined her in the testing fleet. They were briefly joined by an unnamed vehicle, numbered RS-IC-599, whose purpose was to fly the Suborbital Escape Pod Demonstration Test. This mission would see the stage, carrying a dummy second stage and payload, fly unmanned, with crash-test dummies lined with accelerometers occupying the seats in the flight deck. After staging, the flight deck would be jettisoned, to test the ability of the escape pod to recover the crew safely in the event of a suborbital bail-out. The escape pod had to be a spacecraft in its own right, with a closed environment and its own heat shield and landing system for oceanic splashdown.

    September 28, 1977 saw the launch of this officially-unnamed vehicle (though photos released after launch revealed that pad technicians from either Boeing, Grumman, or NASA had chalked the words “Sacrificial Lamb” under the cockpit windscreen), and the first use of the escape pod in flight. The flight deck splashed down about 150 km downrange of Kennedy Space Center, and was recovered by the US Coast Guard for analysis. The dummies were no worse for wear, though the accelerometers revealed a painful 8-G reentry. Better bruised than broiled, though--actual astronauts would have survived that flight. The name inscribed in chalk, sadly, was nowhere to be found--either scorched off on ascent, during reentry, or washed off in seawater. With the flight of the escape pod, the Space Lifter was deemed man-rated.

    Sacrificial Lamb continued her flight after the loss of her flight deck, continuing on automated commands to reenter without a deceleration burn. Heavily instrumented, she transmitted her condition to Boeing and NASA researchers eager to study the effects of hypersonic reentry on such a large vehicle. They hoped against hope that she’d make it down to the ocean for recovery, but sadly this was not to be. Partial telemetry was tracked by US Navy and Coast Guard assets standing by after the main portion of entry, but maximum temperatures were close to the failure limits of aluminum structures. With no pilot at the controls, what might have been chancy for a human was outright impossible. The breakup of the Lamb at Mach 4 was recorded by US Navy radar and relayed back to NASA--setting a record for the fastest recorded glider accident.

    October 12, 1977, saw the first manned launch of the Space Lifter Independence, on a suborbital demo flight, carrying a dummy second stage (loaded with liquid hydrogen, to simulate the proper weight distribution) and a dummy payload. The mission proceeded without a hitch--at 180 seconds into the flight, the engines shut down, and pyrotechnic bolts jettisoned the dummy payload, which was destroyed by range safety officers after the Booster’s deceleration burn. Entering the atmosphere at 1.5 km/s, Commander John Young and his Copilot, Dr. Story Musgrave, piloted Independence to a safe landing at the Shuttle Landing Facility at Kennedy Space Center. STS-A, the first manned test flight of the Shuttle system, was complete.

    1978 saw the first orbital test flight of the Space Lifter stack, when STS-B, crewed by Ken Mattingly and William Thornton flew Constitution with a functional S-IVC upper stage. During this flight on March 19, they delivered an inert 40,000 kg mass simulator into a very low orbit. After a single orbital pass to confirm parking orbit accuracy with ground radars, the SIV-C reignited to lower its orbit and dump the dummy payload into the ocean. In addition to mitigating debris, this proved the ability to relight the S-IVC for additional burns in space on geostationary launches. The successful orbital test briefly renewed hopes that Skylab could yet be recovered, but the time necessary to restore an Apollo CSM to working order and train a crew for the task was deemed too great.

    After this, as NASA worked to prepare the Shuttle’s actual satellite payloads for flight in 1979, the rest of 1978 was spent going through abort scenarios with inert upper stages. STS-C, -D, and -E went through abort scenarios designed with recovery of the Booster, if not the payload, in mind--the first, simulating engine failure close to the end of the Booster’s ascent, was the most benign. The second, conversely, was the most hazardous--engine shutdown at maximum dynamic pressure, the point where aerodynamic stresses on the stack were maximized. This profile called for ignition of the jet engines during ascent, allowing the stage to coast up past the jettisoned upper stage and payload, until the vehicle came down to a manageable flight regime, while the upper stage fell into the Atlantic. Finally, STS-E demonstrated a partial engine shutdown--loss of an outboard engine during ascent. The loss was compensated by shutdown of the engine across from it, giving the vehicle enough thrust to continue ascent to a safe jettison point, but not enough to successfully complete the mission.

    With the completion of the Suborbital and Abort Test Program, Space Transportation System missions switched from assigned letters to flights to assigning numbers. STS-1 was scheduled for early 1979, the first operational flight of the Space Lifter stack, albeit without an Orbiter.
     
    Chapter 5: Countdown
  • “The great bird will take its first flight upon the back of the great swan, filling the world with wonder and all writings with renown, and bringing eternal glory to the nest where it was born.”


    Chapter 5: Countdown


    The passing of the thunderstorms brought a renewed storm of activity at Kennedy Space Center. With the arrival of the Space Transportation System stack back at the pad, the deferred work of preparing the system for flight could resume. The process of preparing a mission for flight was not as simple as “gas-and-go”. Rather, it was a series of steps to prepare the vehicles and carefully check the final systems to prepare for flight over the course of days. Three days before launch, pad technicians stowed and locked down the crew’s in-flight equipment. Checklists, ration packs, and spare navigation equipment were loaded into under-floor storage boxes and secured shut. Two days before launch, ready supplies of various fluids were pumped into tanks on the Launch Umbilical Tower: hydrogen and oxygen for the orbiter’s fuel cells, hydrogen peroxide for the Lifter’s thrusters and APUs, and supercritical helium supplies for the Orbiter’s pressure-fed rocket engines. With that done, the pad technicians, dismissed during that dangerous phase of preparation, returned to continue their work. Analog switches and dials were checked and re-checked, to ensure they were in the proper position--it would not do to have a throttle valve open during tanking. The digital computer’s software was checked one last time, and found good. Inert mass simulators were loaded into bays and seats that, in an operational flight, would carry mission specialists or experiments. A day before launch, the fuel cell valves were opened, and the Orbiter began running on its own power. The Orbiter and Launch Control both sent radio signals to Houston, where Mission Control at Johnson Space Center verified that it could communicate with the vehicle. The mobile clean room provided 200 feet above the ground by the Mobile Service Structure retracted, and the MSS itself rolled back to a safe distance down the crawlerway.

    As the launch approached, preparation milestones were met in quicker and quicker succession, just as a rocket accelerates at an ever-growing rate as its propellant is burned. At T-9 Hours, the air conditioning system in the launch vehicle’s unmanned sections switched to gaseous nitrogen from air. The propellant tanks were purged of gaseous oxygen, to eliminate the risk of fire. At T-8 Hours, rocket-grade kerosene began to be pumped into the lowermost tank of the stack, tripling the stack’s mass in just a half hour. At T-7 Hours, 28 minutes, liquid oxygen was slowly introduced into the upper stage propellant tank, flashing initially to vapor as it hit the walls, but carrying off some of the aluminum tanks’ latent heat. Soon, the tanks were cool enough for liquid oxygen to begin accumulating--a process completed within 45 minutes. At T-6 Hours, 27 minutes, the process repeated in the Booster’s LOX tank. At T-4 Hours, 11 minutes, liquid hydrogen poured into the much larger tank above the upper stage’s LOX tank, a process which wouldn’t stop before the final moments of the countdown--the hard cryogenic fluid boiled without stopping, requiring constant top-off. At T-3 hours, the Space Shuttle stack was, but for the order to fire, a live vehicle. Between the loads of the propellant pushing down on the pad, the expansion and contraction of the aluminum under varying thermal loads, the thick condensation clouds emanating from the cryogenic tanks, and even a subtle swaying in the wind, one could be forgiven for taking that literally.

    As propellant was loading, the four crewmen who would fly the two vehicles through their first joint mission received their briefings. The Booster’s crewmen, veteran John Young and rookie Bob Crippen, had the lower-pressure job--their colleagues in the Booster Pilot group had already put Constitution through her paces. That didn’t reduce their dedication to the task one iota. The Orbiter’s crew, Fred Haise and Richard Truly, had the eyes of the entire agency on them. The pressure had little more effect on their efficiency than it did on the Booster crew. Weather looked good that day, at the Cape and at the abort landing strips in California and New Mexico. The storms that had passed through last week brought a cold front, with high pressures and a clear, blue atmosphere in their wake, and temperatures balmy enough for Haise to joke that he wished the astronaut transfer van were a convertible. As the crews suited up (wearing brown ejection suits, considerably less constricting than the sealed white A7Ls Haise and Young had worn to the Moon), technicians passed on wishes of good fortune and grabbed last-minute handshakes. Smiling and waving, despite Nixon’s goals of routine, ordinary spaceflight, remained part of the astronauts’ job description.

    The four crewmen and a small team of technicians ascended the LC-39A lift. They stopped half-way up, Young and Crippen stepping out to take command of the Booster, Haise and Truly then continuing to their own ship. In parallel, technicians strapped them down into upward-facing seats, awkwardly fitting through a hatch 90-degrees off from its proper orientation. As the last two hours before launch elapsed, Young and Crippen glanced up at the tapering shape of the Shuttle stack, culminating in the irregular tip that was the Orbiter, in between going over their own last pre-flight checks. The Saturn V and its predecessors had tapered to a point. The Shuttle tapered, too, but then bulged outward again to accommodate the Orbiter’s control surfaces. It was a view equally familiar and alien--when flying airplanes, each of them had been able to see the nose in front of them while they sat in the cockpit, but here it was rotated vertically and yet with no sense of motion. It differed as much from ordinary airplane flight as it did from the old Apollo days, when the crew would be cut-off from sunlight entirely by the Boost Protection Cover of the capsule.

    T-2 Hours. All crew members were strapped in. Technicians gave them a last thumbs-up before sealing the hatches on each vehicle, and left them to their own devices. Haise cracked a few jokes with Truly--”It’s not supposed to rain in Houston this week. Think we can get John and Bob to water our grass?”

    The next hour and a half was almost peaceful for the astronauts, little to do but verify that their radios worked every few minutes. Similarly, for the pad technicians, there was little more they could do to influence the mission. All came down now to the men monitoring telemetry at Launch Control and Mission Control, who could yet call a halt at any moment. In the last few minutes, the stack shuddered as its two main stages pressurized and the engines were purged with helium. The huddled lines of flight controllers bent over their consoles, watching their telemetry as the mission-critical events streamed by.

    In the last few minutes, the stack shuddered as its two main stages pressurized and the engines were purged with helium. The huddled lines of flight controllers bent over their consoles, watching their telemetry as the mission-critical events streamed by. A crowd of three-quarters of a million onlookers gathered at the viewing sites. As they listened, the public affairs officer recounted events as the clock wound rapidly towards zero.

    The testing of the second stage thrust vector control was a whining noise above Haise and Truly's heads. Back in Houston, an engineer nodded assent to the Flight Director. TVC go.

    With three minutes left to go, the auxiliary power units on the booster and orbiter whined to life within the stack. Dials jumped for a moment then settled in the stack's cockpits. Another nod from a flight controller followed as the telemetry streamed back to their consoles. Vehicle on internal power.

    One minute left. Haise and Truly watched above them as the orbiter tested its hydraulics, flexing its rudder and elevons. There was a distant hydraulic whine as Constitution tested her own control surfaces: rudders, elevons. The doors covering her jet intakes flexed open, then closed again. Distantly, another controller confirmed it. Hydraulics go, all flight controls nominal.

    Thirty seconds left. The final service arms retracted, leaving the vehicle standing alone. A flight controller smiled tensely as the hydrogen levels inside the interstage stayed right down the middle as the tanks came up to pressure. Tank pressure go.

    The final seconds ticked down as the commentator counted events off. Fifteen seconds. Ten seconds. Nine. Eight. Seven. Six. Main engines start. A rush of fire spun up the F-1B turbopumps. RP-1 and LOX poured into the combustion chambers at phenomenal rates. Mixing, they sparked and ignited. Hot gas poured out the throat far faster than the speed of sound. A flash of flame billowed up around the vehicle, then was sucked down the flame trench by the speed of the exhaust flow leaving behind a cloud of smoke lit from below.

    Five. Four. All engines on. Bolts on the hold-down arms absorbed the load. Now they weren't holding the massive bulk up, they were tethering it down as it pushed for the sky. Three. Two. One. Controllers waited for the computer's final decision. The rest of the world held their breath for the next word from the launch announcer...



    As the final years of the 1970s wound down, NASA found itself once more in a race to debut a new system to accomplish something revolutionary in spaceflight. However, unlike the widely-followed missions leading up to Apollo, the debut of the Space Transportation System was not a matter of great international stakes, nor was the deadline one set by a grand vision. The clock which was winding down was not one driven by public attention and international press, but by schedule overruns adding up and budgets running low. However, if the stakes were lower, the challenges were no less intense--and with the end of Apollo and the aerospace recession, the number of empty offices, smaller budgets, and generally lower public engagement only exacerbated the situation.

    In spite of this, the Space Lifter portion of the Space Transportation System was largely on track, regularly marking items off the the program’s Gantt charts. The abort tests were complete, the first orbital launch of a demonstration payload had been carried out, and the third booster, RS-IC-603 Intrepid, was in the final stages of assembly at Boeing Field in Washington. Not everything was on track: the final assembly of RS-IC-604 and the planned order for RS-IC-605 were being delayed as a cost-saving measure to divert funds from the Space Lifter to the cost overruns being encountered on the Space Shuttle orbiter. Still, for the most part, the Space Lifter remained on track, ready for the STS-1 first operational flight in March of 1979. The Space Shuttle program as not as fortunate.

    The Space Shuttle program had lagged behind the Space Lifter from the beginning, with a ten month difference between the award of the booster contract to Boeing and the award of the Space Shuttle contract to North American Rockwell. The debates over configuration, thermal protection systems, and more had driven the program to the ragged edge where it seemed as though the Space Lifter might become the only surviving element of the Space Transportation System. As the decade wound on, this became a theme in the Space Shuttle program. While the Lifter began its development rapidly following the contract award, building on almost a decade of studies in reusable winged S-IC stages, the Space Shuttle orbiter had to cut a new path. Even drawing on histories of lifting body studies by NASA and North American Rockwell’s Martin partner on the project, wind tunnel tests and computer simulations were needed to verify where the orbiter might expect to see peak heating during atmospheric return, determining which portions of the all-important Thermal Protection System could be thermal blankets, which could use high-temperature ceramic tiles, and which would be forced to use new reinforced carbon-carbon composites. Even while this work was ongoing, hundreds of engineers were beginning the process of laying down plans for the structural design of the vehicle, its orbital maneuvering systems, its payload bay doors and thermal radiators, its power systems and avionics, and the interior design of its crew spaces. All of these had been addressed by NAR’s original bid submission, but building the actual vehicle would require a higher level of detail.

    The result was that while the first flight-ready booster rolled off the assembly line in the middle of 1976, the first Space Shuttle analogue suitable for even glide testing didn’t make its appearance until almost a year later, when OV-101 Pathfinder rolled out of Rockwell’s Palmdale assembly plant. Unlike the RS-IC, which could ferry itself around the country with its jet engines, the Space Shuttle required assistance getting airborne. Pathfinder made her first flight in a captive carry on the back of a modified 747 at Edwards Air Force Base in November of 1977, This was the start of a year-long “Approach and Landing Test” series. The prototype orbiter took to the sky again and again on the back of its carrier, first with a set of five flights with the orbiter just an unpowered parasite on the back of the 747, then three more “captive-active” flights where, for the first time, the orbiter flew powered and with a crew onboard though it never left the back of its carrier. Finally, in September of 1978, the first free flight of the orbiter took place, With Fred Haise at the controls, Pathfinder glided free and clear as the 747 carrier dived away from beneath her, then the Shuttle came in for a center-line landing on Edward’s main runway. It was a major step forward for the troubled program, but while the flight and the three additional flights that followed proved that the Space Shuttle would be able to glide and land after a flight to space, the program still faced issues with the systems involved in an orbital flight.

    Even as Pathfinder was making her flight debut, issues were surfacing in other areas of the program which put the final assembly of the first orbit-capable vehicle behind schedule. The two biggest problems developed with the design and testing of the orbiter’s launch abort system and the orbiter’s all-important heat shield. In order to boost a fully-loaded 26 ton orbiter and a 8-ton payload clear of the failure of a Space Lifter, more than seven metric tons of propellant otherwise earmarked for orbital maneuvering would have to be burnt in less than seven seconds. This would require a set of sea-level optimized high-thrust abort engines. In the end, the proposed system was four LR-91 engines fitted with a sea-level-optimized nozzle, with a single vacuum-optimized AJ-10 placed on the centerline of the vehicle for orbital maneuvering. The use of a pump-fed engine for this critical role was a major question mark in the Shuttle’s design phase. Reducing the risk was key. Though the LR-91 was already human-rated for use in the Titan GLV second stage, an extensive series of trials were carried out to verify that the designed cluster could be activated in time reliably, with more than a dozen firings of an integrated engine cluster made on a specially-built test stand at Edwards. Finally, however, the testing was completed.

    While the tests of how the Shuttle would be lifted into orbit and escape disasters were complete, the problem of how the vehicle would make its return was still up in the air. The high-tech silica tiles of the Shuttle were revolutionary, offering the same thermal resistance of a metal hot-structure while divorcing the exotic materials of the TPS from the underlying traditional aluminum airframe. The selection of tiles over a metallic hot structure had been a key point of debate in the leadup to the Space Shuttle, but the wisdom of the selection was proven as the development of the airframe was able to proceed while tile production and testing was still ongoing. Tile development was initially trouble-free, but 1975 tests intended to look at the potential effects on the orbiter of losing tiles in flight revealed a potentially critical issue. These tests involved the use of a new arcjet-equipped vacuum chambers at Johnson Space Center to test the effects of entry-force heat and pressure on test articles the vacuum environment inside the ARMSEF. Initial assumptions had held that the airflow around the orbiter would be largely in line with the skin, and that holding up under 2 psi of force attempting to pull tiles loose would be sufficient. Unfortunately, this assumption would be proven wrong from two ends in 1975. The ARMSEF tests revealed that the tiles would need to withstand far higher forces to stay attached during entry--and that the current tile adhesives were not up to the challenge. Internal testing at Rockwell on early production samples around the same time showed similar results, but were initially attributed to early production quality-control issues. Tight budgets had restricted follow-on testing. However, with two tests coming to the same conclusion at the same time, NASA was forced to evaluate the existence of a more serious concern. Almost all of 1975 and much of 1976 was spent in tests to establish how bad the problem truly was. Re-analyzing the flight assumptions using the latest Computational Fluid Dynamics models and wind tunnel testing confirmed what ARMSEF testing had indicated: the tiles needed dramatically higher adhesion than had been originally called for. Moreover, Rockwell’s tests were repeated on tiles pulled from those intended for assembly of OV-102 Endeavour, which showed the same excessive variation in bond strength as the original test batches.

    While the Space Shuttle program had known from the beginning that they would have to fight to make the planned launch date, ongoing development raised new problems. In 1976 with less than two years before the planned first flight of the Space Transportation Systems, it now looked like even if NASA could prove the orbiter could glide and that it could abort safely and maneuver in space, it might not be able to survive returning to Earth. Fortunately, a new solution was found to “densify” the tile cement using fine silica grains stabilized with ammonia. The revised densification was begun, but as it proceeded, it revealed further issues with variable bond strength. Worse, the tools to evaluate tile strength also proved troublesome: in order to test tiles before flight, non-destructive testing of tiles was planned using an ultrasound system. During initial tests of the system on the newly densified tiles as they were installed onto Endeavour in 1977, the system proved temperamental. Tuned to avoid missing any “false negative” tiles which might actually be defective, it instead threw “false positives” for one tile in every ten. Actual testing, however, revealed that only one tile in a hundred was really defective. The result was that the process of cladding OV-102 in her protective mantle of tiles extended well beyond the end of 1977. Even as OV-101 was testing the Orbiter’s performance in the craft’s maiden glides, OV-102 was still more than a year behind the original delivery schedule. Arrival of the first Space Shuttle orbiter at Cape Canaveral was now expected no sooner than 1980.

    While the Space Shuttle was struggling on the path to flight, the Space Lifter was proceeding through its final testing. The decision of desperation in 1971 to split the Space Transportation System into a Lifter and a Shuttle now began to acquire an air of quiet brilliance as issues with the Space Shuttle pushed its debut out even as the Lifter was cleared for flight. Originally, it had been hoped to debut both vehicles together, inaugurating the Space Transportation System with a manned mission. This would both symbolically end the gap in manned spaceflight since Apollo-Soyuz in 1975, as well as cementing Lifter and Shuttle as part of the indivisible STS in the eyes of the public. However, while a slip of a month or two to wait for the Shuttle might have been acceptable, the Space Lifter was ready for its first operational launch in early 1979. It had already spent the year since its first dummy launch profile in 1978 testing increasingly unlikely abort scenarios--further delays might bring the entire program’s funding into questions. While the Shuttle engineers worked to fix their issues with the tiles and accelerate Endeavour’s preparations for delivery, the Lifter proceeded to the pad for the first time with a real payload on top.

    STS-1 lifted off on March 23rd, 1979, with Joe Engle and Gordon Fullerton at the controls of the booster Constitution. Strapped to the top of the S-IVC was an internal NASA payload, the communications satellite TDRS-A, the first of the new NASA Tracking and Data Relay Satellite System. Once deployed to geostationary orbit, the TDRSS constellation was intended to facilitate communications not between locations on Earth, but between Earth and orbiting Space Shuttles without the requirement for the global network of scattered ground stations used during the Gemini and Apollo era. TDRS-A was not only a major step for enabling the Space Shuttle program, however--it was also an important proving ground for the commercial viability of Space Lifter. The launch of an unmanned spacecraft to geostationary orbit on STS-1 would be the final proof of Space Lifter’s ability to do the same for future commercial missions. Flying the Space Lifter to geostationary orbit without a third stage was not particularly efficient--its payload dropped by three quarters, from more than forty metric tons to only ten. Even so, the Space Lifter was capable of lifting far more than the two tons of TDRS-A. The STS-1 mission demonstrated the first of many solutions to the excess capacity problem during a picture-perfect ascent. After 23 minutes coasting through space after primary ascent, the S-IVC relit its engines for the geostationary transfer orbit (GTO) insertion burn. During this burn, the S-IVC pushed TDRS-A onto a trajectory with a much higher apogee than standard GTO--a so-called “super-synchronous transfer orbit”--while also eliminating a larger portion of the orbit’s original 28.5 degree inclination. These maneuvers, more demanding of the second stage’s performance, used up some of the margin of the Space Lifter stack to leave TDRS-A closer to its final geostationary orbit than if it had flown on a traditional launch vehicle.

    The next mission was scheduled four months later, following final evaluation of detailed performance data from the STS-1 mission. Launching for STS-2 on July 29, 1979, the booster Independence made her own operational debut, demonstrating another option for commercial geostationary orbit payloads hitching a ride on the Space Lifter. The mission carried not one but two TDRS satellites, TDRS-B and TDRS-C. The pair were contained within a special structure, the “Multiple Launch Adaptor,” which supported the TDRS-C spacecraft above the TDRS-B spacecraft, each with its own set of mating fixtures, power supplies, and other interfaces. Even with five metric tons of payload and the mass of the MLA, STS-2 still had enough payload margin to boost its twin payloads into a super-synchronous GTO. In its first two operational launches, the Space Lifter amply demonstrated the values which made it attractive to commercial launch customers.

    Lifter’s third flight, STS-3, would once again test a capability enabled by the Space Lifter’s massive payload capacity--one with attraction both to NASA and to NASA partners. However, this time the partner customer was far less public. Observers watching the mission in the evening of November 17. 1979--the first night launch of the Space Lifter program--saw the glowing trail of the rocket’s trajectory head out nearly due east over the Atlantic, as on STS-1 and 2. However, shortly after Constitution separated, with her retro-propulsion burn providing a second false star in the night sky, the S-IVC altered its heading to the north, cutting away from the equator to skirt the coast of Newfoundland in a massive “dog-leg” trajectory. The maneuver was incredibly expensive in terms of delta-v: the steel payload simulator was barely more than the stack’s GTO capacity. However, the benefit was that it enabled the launch of a payload to a 98-degree sun-synchronous orbit from Cape Canaveral, instead of from the traditional American polar launch site at Vandenberg. With advocacy from Californian representatives in Congress, the US Air Force was converting the partially-completed Titan II launch site SLC-6 at Vandenberg into a site for the Space Lifter. This would enable the launch of full-payload missions including the Space Shuttle to polar orbit. However, the site was still several years from completion. In the meantime, the “dog-leg” would do for conventionally-sized payloads. Even with the massive inefficiencies of the dog-leg, Space Lifter could still match the payload of a Titan III rocket with slightly lower cost.

    After STS-3, the Space Lifter had demonstrated its key operational mission modes for unmanned payloads, and was declared fully operational. Subsequent missions proceeded at a faster pace, and with less variation between flights. STS-4 in December 1979 followed just over a month after STS-3. As a holiday present to the agency, it saw the booster Independence deliver two packages wrapped in the STS-MLA. The bottom payload was the fourth operational TDRS satellite, completing the initial constellation. The upper slot (with less risk of fouled deployment) was reserved for the Space Transportation System’s first commercial customer, the SBS-1 satellite. One of two HS-376-based satellites ordered by Satellite Business Systems from Hughes, it was the first of many other HS-376 busses which would fly on the STS. The Space Lifter would fly two more such missions during the first half of 1980, with STS-5 in February and STS-6 in April. In June, the Space Lifter flew its first classified DoD payload on STS-7, the debut flight of RS-IC-603 Intrepid, the first booster whose construction was funded by the DoD. This was an operational duplicate of the “dog-leg” polar trajectory tested on STS-3, with the stack inserting a classified payload into sun-synchronous orbit. Officially classified for many years, the launch was later revealed to be the latest in the KH-9 series of satellites.

    While the Space Lifter’s activities were vanishing into a haze of routine, the Space Shuttle was finally making visible progress. With the last rounds of fixes to the tiles completed in fall of 1979, OV-102 Endeavour rolled out from Rockwell’s Palmdale integration site for its first ferry flight to the Cape. Engineers breathed a sigh of relief when she arrived safely intact in Florida--the airflow of the ferry flight served as a validation of the test results in the wind tunnels on the tiles, and not a single one came loose. The arrival of the orbiter at Kennedy Space Center instantly absorbed the attention of press, visitors, and innumerable technicians and engineers. For more than six months after her arrival in November, Endeavour waited in the Operations & Checkout Build at Kennedy as test engineers put her systems through their paces. With the tests complete (and the secrecy around the VAB payload processing areas relaxed following STS-7), OV-102 was rolled across the five miles to the VAB on June 24, 1980. The booster Constitution was next in the rotation, and was rolled into the massive facility a week and a half later once the final pre-stack checks were completed on the Shuttle. With Space Lifter’s maiden orbital test mission two years in the past, tourism at the Cape and national press attention had been slipping. The arrival of Space Shuttle Endeavour for the debut of the manned STS was a shot in the arm. Hundreds of tourists a day watched as the booster was lifted to vertical and mated to the MLP, then joined by the S-IVC stage. Finally, eight years after the approval of the program, the Space Shuttle Endeavour was grabbed in turn, lifted off the transfer aisle floor, and mated to the top of the Space Lifter stack. The STS-8 stack was complete. Rollout to the pad followed on July 15, 1980.

    Simply completing the assembly, however, wasn’t the sole issue for the mission. STS-8 proved that while the full STS was ready for its debut, space launch operations were still anything but routine. During fill testing of the stack at the pad following rollout, a buildup of hydrogen gas was measured in the interstage between the S-IVC and the booster’s nose. Work stopped overnight. After waiting for the tanks to empty and vent clear, McDonnell-Douglas engineers and technicians entered the interstage from access gantries, and opened every panel they could. With the quick and dedicated work, and no shortage of good luck, the issue was found to lie in a non-critical bleed valve which could be replaced and tested on the pad. After careful approval, it was. The entire resolution had taken only a day. Remaining pad tests proceeded smoothly and hopes rose that the mission might go off on schedule. Unfortunately, storm clouds were on the horizon in the most literal sense--a tropical storm in the Caribbean had turned north and threatened the Florida coast with a hurricane. With worries about the security of the Shuttle’s tiles still foremost in everyone’s mind, the decision was made to roll the stack back to the VAB for safety. It proved unnecessary, as the tropical storm collapsed into only heavy thunderstorms instead of intensifying, but as several lightning strikes were recorded on KSC grounds, program managers agreed it had been the correct call.

    The passing of the front and the return of the stack to the pad on July 21 kicked preparations to flight into high gear. The stack seemed no worse for the wear of two rollouts, and all systems passed inspection over the next few days. The Flight Director gave the traditional call to stations on July 24, and the final two-day launch campaign began. Closeout began on the orbiter and booster cockpits, onboard consumables of both vehicles were topped off and sealed, and the flight crew finished their final simulations. For the debut mission, NASA had assigned its most experienced Space Shuttle crew, Fred Haise and Richard Truly. Haise and Truly had been among the pilots who had trained for Shuttle flights during the Approach and Landing Tests, and indeed had flown together on OV-101’s maiden glide flight almost two years before. Now, they were assigned the task of taking Endeavour to space. The pair took the attention in stride, focused on the tasks at hand.

    The storms left behind a cold front, July 26th brought predictions of clear and sunny weather. The scheduled Saturday flight brought an audience from around the country to Cape Canaveral to witness the launch. Almost three-quarters of a million people followed along in the countdown, circulating around the visitor's center and viewing sites. They began to gather in the stands. Visitors chattered as they listened to the voice of the public affairs commentator run down the increasingly routine steps of preparing the vehicle: propellant filling on the booster and second stage, pressurization of the tanks, the arrival of the crew at the launch pad, the sealing of the Shuttle and Lifter cockpits and the retraction of the white rooms. In the launch control and mission control rooms, the attitude was just as tense. As the vehicle came to life in the final computer-controlled sequence, flight controllers were focused on the data streaming across their consoles.

    The auxiliary power units whined to life. Flight controls twitched as they were tested. As the final umbilical arms retracted, the tank boil-off stopped and pressures rose to flight levels inside the tanks. Seconds later, a dense cloud of spray shrouded the surfaces of the mobile utility tower and covered the entrance of the flame trench. Main engine start with six seconds left sent a roar across the Florida swamps to the viewing stands. The stack shuddered slightly as bolts held it down against the thrust driving that wave of sound. Constitution wanted to fly. In the final instant, the computers of the stack made their analysis. All engines running. All systems go. As an electric signal from the stack triggered the explosive bolts to release the hold-downs, the launch announcer's voice carried to the waiting crowd a single ecstatic word:

    "...Liftoff!"

    Authors' Note:

    We hope that you've enjoyed Part I: Pre-Flight of Right Side Up: A History of the Space Transportation System! Part II will go up after a 3-week hiatus, but in the mean time, we've got pictures of the Lifter, Orbiter, and S-IVC that will start going up in the next few days! Stay tuned!
     
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    Chapter 6: Liftoff

  • The eighth launch of the Space Transportation System and the first landing of the Space Shuttle Endeavour is the historical equivalent of the driving of the golden spike which completed the first transcontinental railroad. It marks our entrance into a new era.

    -President Jimmy Carter, remarks at landing of STS-8.

    Chapter 6: Liftoff

    "3...2....1....Liftoff! We have a liftoff!" Faster than human reflexes could comprehend, the launch computer's sequencer fired the electronic circuits to the tiny explosives in the bolts holding the rocket to arms on the pad. The pop of the tiny detonations vanished as the stack released the energy that had been building since main engine start, jerking like a colossal spring. With the bolts released, the hold down arms lept backwards into protective housings, retreating in seconds as thousands of tons of rocket rose on a tide of flame. Behind the rocket, there was a preview of hell, a baptism of fire, a blaze of light, and noise so loud it ceased being sound and was only fury. The Lifter’s crew, for a moment, could see the tower and umbilical arms in front of them lit up from below by kerosene fire--but only for a moment. The vibrations shook loose a cocoon of ice, falling from the sides of the S-IVC to bounce against the triple-layer windows of the Lifter’s cockpit before veiling the Lifter itself in a cascade of condensation and ice.The booster leaped away from the launch pad, trailing an incandescent tail of steam, carbon dioxide, and soot. As it began to gather speed, the remaining umbilical arms swept out of the way, just barely clearing the massive ship in a well-coordinated dance.

    The Lifter climbed, pitching slightly to increase distance from the Umbilical Tower, before steadying and gathering way. The veteran Launch Umbilical Tower was built for the Saturn V, and loomed over the Shuttle stack, even with the S-IVC stretch. Still, within seconds, the nose of the Shuttle cleared the tower. Now, all that was visible in front of Haise and Truly in the Orbiter’s cockpit was the clear blue sky above. It took another six seconds for the rest of the stack to follow, the Lifter rising into the sky on a column of flame. Eight seconds after the hold-down arms released, the Lifter’s wingtip rudders finally cleared the tower, leaving Earth behind in a cooling cloud of steam. The staff several miles away at Kennedy Space Center’s Launch Control Complex leaned fractionally back from their consoles--the mission was now out of their hands. Control had been handed off to the Manned Spaceflight Center in Houston, which seamlessly took over the job.

    The stack climbed slowly, the engines and control surfaces working to turn it onto its course. The belly of the Lifter and Orbiter turned to the sky as the stack rolled, and then the horizon re-entered the very periphery of the crew’s windows as it pitched over. The turn and the continuing shaking knocked clear the last of the ice and debris. The crew in the Lifter once again had a clear view of the stack rising above them, and the sky and ocean beyond. It was practically all they could see--as the rocket climbed, the shaking of the massive engines and the air resistance mounted. The pilots had to focus intently to resolve their instrument panels. Still, they could see enough. “Houston,
    Constitution. We have a pitch and a roll program! Trajectory nominal,” the Lifter’s pilot John Young called over the radio. “We’re belly up, but we’re keeping a positive attitude,” he continued on the internal comm channel. Fred Haise up in the Orbiter grunted out a chuckle.

    Back at the Vehicle Assembly Building, a multitude of technicians were taking a break from processing
    Intrepid for her next flight, gathered on the roof for the best view of the launch. Many aimed cameras to follow the rocket. Amateur photographers wielded Nikon and Canon cameras with telephoto lenses, clicking away as rolls of 35 mm film spun rapidly through the machines. Others were even more amateur, and make do with their family Polaroids. Some just gaped. It was just a short diversion for the staff, though. Even as Constitution climbed above them, her sister was being prepared below. When the show ended, the technicians would once again descend into the VAB’s cavernous interior and continue their work on the next launch of Constitution’s youngest sister.

    Across the Banana River, at Space Launch Complex 40, their counterparts with the United States Air Force were also breaking their labor to follow
    Constitution and Endeavour with eyes and cameras. There, a Titan IIIC stood cradled within its servicing tower, soon to be mated with one of the Department of Defense’s communications satellites. The Air Force technicians, and their counterparts from Martin-Marietta, cheered the Lifter and Orbiter on as they clear the tower, but there was a touch of unease in their minds--it was an open secret that the Lifter was to replace all American rockets bigger than the Scout. Just how many more Titans would they launch before their pad was mothballed?


    The flight of STS-8 was, but for some minor teething problems with the Orbiter, totally nominal. At T+120 seconds, the Lifter’s engines shut down and the S-IVC pulled away, its own J-2S-2 starting up at T+122 seconds, the disposable interstage falling away between them. As the upper stage carried the Orbiter the rest of the way to Low Earth Orbit, the Lifter continued its rapidly-slowing coast to 109 km--past the Karman line--before hydrogen peroxide thrusters turned it around and pointed its engines down-range. The center F-1B lit again, slowing the craft down and orienting it for a return to its launch site, burning off the remaining supplies of propellant on-board. The crew got to enjoy minutes more of micro-gravity, though they were strapped into their seats and so couldn’t move around the cabin. As the Lifter fell back into the atmosphere, the crew pointed the nose up, presenting the almost-flat aluminum underbelly to the incoming air flow, the better to maximize drag. Just 15 km above the Earth’s surface, the air inlets for the turbojets opened. A combination of ram pressure and decomposing peroxide from the vehicle’s tanks spun up the turbines, first a pair, then more in sequence. Seven of the eight started with no trouble, and a second start attempt brought the last to life as the Constitution made her turn back to land. On her own power, the Lifter descended as she covered the 600 kilometers she had crossed in less than fifteen minutes. Without drama, the big winged booster touched down at the Landing Facility at Kennedy Space Center, returning to the ground less than 20 minutes after she had left.

    The Orbiter continued up, as the S-IVC burned for over 10 minutes until its propellant tanks were depleted. The S-IVC stopped just short of a fully circular orbit--the Orbiter would have to finish that job itself, as the upper stage’s perigee remained just inside Earth’s atmosphere. Separating from the S-IVC, the Orbiter’s AJ-10 engine provided the last little kick to circularize the orbit at three hundred kilometers. For the next 24 hours, Haise and Truly put Endeavour through her paces. They checked the communications systems (using TDRS for manned orbital missions for the first time) and verified that the life-support system functioned in microgravity. They opened the payload bay doors and depressurized the airlock, though no EVA was planned for this particular flight. The crew extended the Orbiter’s Canadian-built robot arm, including using a camera on the end to photograph the thermal insulation tiles on the Orbiter’s dorsal surface. The images confirmed that the densification procedures implemented at Rockwell years earlier had successfully mitigated the feared tile-loss issues--only a few tiles were missing or showed damage, none in critical locations.

    Reentry was a bit hairier--though the Shuttle returned to Kennedy Space Center in good shape, the vehicle’s actual performance at hypersonic velocities differed from that predicted on the ground. Though the computer at times overcompensated for aerodynamic stresses, it was not far enough outside expected tolerances to require Haise to take manual control. The descent remained fully automated until the last minutes of flight, at which point Haise and Truly took over and brought the craft to a successful landing at the Shuttle Landing Facility, just meters away from where the Lifter had touched down the previous day. By this point, however, the Lifter had already been rolled over to the Booster Processing Facility.

    Haise and Truly got a hero’s welcome at Kennedy Space Center, greeted first by Young and Crippen, and then, in celebration of the end of the Space Transportation System Test Program, by President Jimmy Carter, who gave a brief speech at the Landing Facility congratulating the astronauts on a successful flight and formally inaugurating the Space Lifter portion of the Space Transportation System as America’s premier operational launch vehicle. Notably, Carter tied the successful tests of the STS with his own administration’s goals of freeing the US from its dependence on foreign fossil fuels, recalling the tenth principle he’d outlined in his 1977 speech on his proposed energy policy, which said “we must start now to develop the new, unconventional sources of energy we will rely on in the next century.” The Carter Administration, since 1978, had flirted with orbital solar power satellites as a clean, fully-renewable, and high-power source of electricity, and with the successful landing of STS-8, Carter felt confident enough to suggest that the Space Transportation System opened the way to such a system. “In the future, vehicles like this and its successors may go on to revolutionize how we power our planet, and other benefits of spaceflight we can only dream of today. But it begins with this flight here today, and I congratulate the crew and the team which have brought them here." Though the flight of STS-8 took place toward the end of Carter’s administration, historians credit it with swinging the state of Alabama to him in the 1980 US Presidential Election, as voters in Huntsville and its environs supported the man who had brought the space program to a new triumph. This would be the last time that Alabama went Democrat, however.

    Like a sonic boom propagating through the atmosphere, the effects of the Space Transportation System were not limited to the United States but were felt across the world. With the fourth consecutive failure of Korolev’s N-1 rocket in 1972, the Soviet Union had finally put its lunar program to rest and shifted gears, placing the late Korolev’s rival, Valentin Glushko, in command of the program. With an efficiency that would have warmed the hearts of Stalin and Beria, Glushko purged the N1-L3 program from official Soviet history, scrapping the incomplete launch vehicles and ordering the NK-33 engines his competitor Kuznetsov had developed destroyed. Only a secret countermanding order from the other designer himself saw them redirected to a remote storage facility instead. Instead, Glushko envisioned a new, modular launch system built on a common series of kerosene-oxygen tanks and engines that could put payloads as small as 30 tonnes and as large as 250 tonnes. The new system would be fully expendable, and its end goal would be a Soviet conquest of the lunar beachhead abandoned by the Americans.

    As ambitious as Glushko’s vision of a Red Moon was, it found little traction among those elements of the regime most responsible for allocating funding. Both the Ministry of General Machine Building and Ministry of Defense objected to the program’s high cost (one hundred billion rubles) and lack of apparent utility. The sizing of the core stage for 250 tonnes made its smaller variants inefficient for lofting 30-tonne payloads, and the cancellation of the Saturn V in the United States (together with Glushko’s own cancellation of the N-1) raised doubts about the usefulness of heavy-lift vehicles in general.

    The announcement of the Space Transportation System began to change minds among the USSR’s decision-making class. Though the Lifter’s low cost-per-flight was deemed feasible by the Soviet Academy of Sciences, such cost savings were not quite as meaningful in the Soviet command economy as they were in the American market economy. The high flight rate the Americans forecasted, however, was far more interesting to Soviet analysts. The weekly flight rates proposed for the Space Lifter and the monthly Orbiter missions indicated that the United States planned to increase the mass it sent to Low Earth Orbit by an order of magnitude, and to return some 100 tonnes to Earth from space every year. The only identifiable reason for such a massive increase in capability would be a massive military undertaking--a new space-based weapons system, or an advanced anti-missile defense system. The Orbiter’s unique ability to maneuver in the atmosphere at hypersonic speeds also raised troubling questions about the military applications of such a vehicle--specifically, the ability of a hypersonic orbital airplane to dive down onto the USSR from the south, drop a thermonuclear payload, and then return to its launch site, having managed a sneak attack that escaped the notice of the Soviet early warning satellite system.

    Whatever the Americans were up to, it was clear that the maintenance of the balance of power between the superpowers required a Soviet answer. The Lifter had, in the Soviets’ eyes, metamorphosed into the launcher for a vast fleet of space-based weapons, and the Orbiter into a hypersonic dive-bomber of doom come to eradicate the entire Soviet people. It was with this in mind that in February 1976 the USSR Council of Ministers and the Central Committee of the Communist Party issued a joint decree “On the Development of a Reusable Space System and Future Space Complexes”, directing the creation of a Soviet version of STS.

    The Politburo’s demand for an answer to the STS did not deter Glushko from pursuing his lunar plans. Though nominally satisfying the Party’s demands, Glushko’s design bureau optimized their new rocket family as boosters for a future super-heavy-lift vehicle. Though the maximum payload of the new family, dubbed “Groza,” or “Thunderstorm,” was only 50 tonnes to LEO (still greater than the maximum capability of the STS), the system enabled a lunar program using an Earth Orbit Rendezvous architecture, and, as stated, could support far greater payloads if only a bigger core stage were available.

    Each Groza rocket was based on a first-stage vehicle called Raskat (“Thunderbolt”, literally “Peal of Thunder”), a 3.9-meter-diameter, 40-meter-length booster with a new, phenomenally powerful engine--the RD-170, an oxidizer-rich staged-combustion-cycle motor. Each Raskat was equipped with swing-wings and landing gear, which would deploy after booster separation and allow the vehicle to make an autonomous landing at an airstrip. The second-stage vehicle, a new, 4.15-meter stage that shared its diameter with the upper stage but which used altitude-optimized RD-170 engines, would light after booster separation, and propel an upper stage (either a new, large upper stage for heavyweight payloads or an existing Blok-D for small ones) the rest of the way through the atmosphere.

    Though Glushko’s attention was focused on the booster and its eventual lunar payloads, the Soviet military’s interest was primarily in the glider that would fly atop Groza, a payload dubbed Uragan (“hurricane”). Uragan was administered by the Ministry of Aviation Industry, whose engineers drew on work done in the late 1960s on an orbital space plane called the Mikoyan-Gurevich MiG-105, AKA “Spiral.” The “Spiral” concept was scaled up to match the capabilities of the American Orbiter, under the direction of the original “Spiral” chief designer, Gleb Lozino-Lozinsky.

    Though based on internal Soviet design work and even subscale prototypes flown well before the American Shuttle announcement, international views were that the Soviets were merely copying the Americans. Though not true in a technical sense, it was true in a strategic one: Uragan was scaled to resemble the American's orbiter in most capabilities, as the orbiter was the portion of STS with which the Soviet's analysis of economics found the most issue. Clearly the Americans had other plans for using it, and the Soviet Union wouldn't be left behind if they had to copy the Americans to the rivet.

    In preparation for orbital tests of the full-sized Uragan, Lozinsky’s team manufactured a series of sub-scale orbital and suborbital test articles, collectively referred to as “BOR,” from the acronym for “Unpiloted Orbital Rocketplane”--an acronym that, conveniently, also suggested another violent weather phenomenon, the snowstorm (In Russian, “Buran”). From 1978 to 1980, orbital and suborbital test flights of several BOR gliders validated the aerodynamics and thermal protection systems of the larger Uragan. Following close behind were low-velocity approach and landing tests of a piloted Uragan test article, a vehicle without rockets or thermal protection systems, dubbed Ptitchka (the diminutive form of “Bird,” i.e. “Birdie”). Piloted by Igor Volk and Rimantas Stankyavichus, Ptitchka was launched from the dorsal surface of a Myasishchev 3M bomber and brought to a successful landing at Zhukovsky Air Base over and over, validating the aerodynamic design of Uragan.

    Even as Fred Haise and Richard Truly took Endeavour through her paces on STS-8, the Soviet orbiter program appeared well on the way to matching the Americans’ orbital capabilities by the mid-1980s. Unfortunately, it was not the glider but the booster that plagued the Soviet design effort. The RD-170, utilizing the comparatively untested oxidizer-rich staged-combustion cycle, ran at higher pressures and temperatures than previous engines, and, due to its exotic combustion chemistry, required new metallurgical techniques. Validating each of the techniques was a long and arduous process that cost Glushko dozens of engines and at least one test stand, and delayed successful tests of the Groza booster system until the mid-1980s.

    The Soviet Union was not the only foreign power to take note of the new American program. Across the Atlantic, European policymakers debated the impacts of new launch system on the American near-monopoly on commercial satellite launch, while the failure of the Europa rocket program very nearly ended the united European space program before it began, driving new wedges between the biggest of the European aerospace players.

    In the aftermath of the Second World War, the United Kingdom eventually came to terms with the loss of its empire and its second-tier status. Though Britain developed her own atomic weapons and the missiles and bombers with which to deploy them, she increasingly lost the will and the financial capability to maintain the aeronautical sector that had, at its height, burned Nazi Germany to the ground. The United States helped speed this decline along by offering subsidized launches of British satellites on American rockets, and by offering American-made missiles for Britain’s nuclear deterrent. In the cold arithmetic of economics, the British rocket program that had produced Blue Streak and Black Prince was found wanting. The Blue Streak was finally cancelled as a missile program in 1960, though it had a brief second lease on life.

    France’s rocket development program followed a diametrically opposite trajectory. France reacted to her humiliation in the Second World War by attempting to reassert herself as the great power she had once been. Under the leadership of President Charles de Gaulle, she invested in nuclear power plants, nuclear weapons, and, bearing fruit at last in the early 1970s, a missile fleet that gave her a nuclear deterrent wholly independent of the American triad. French scientists and engineers tackled the problem of orbital launch with equal vigor and for much the same reasons--the French Republic was not a second-rate power to beg for scraps from the United States. Finding sympathetic allies in those sectors of the British government that did not want Blue Streak to have been a total waste, and who remained optimistic about the economic prospects of European-launched communications satellites, the French committed to a 1-tonne-to-orbit rocket for the 1960s. Italy, Belgium, the Netherlands, West Germany, and Australia would join this effort as the 1960s continued, forming the European Launcher Development Organization (ELDO), whose stated goals included the development of an independent European satellite launching capability.

    ELDO’s job was easier said than done. The Europa rocket design called for stages from Britain, France, and West Germany to be combined into a single launch vehicle in a project to which not all the partners were equally committed. Britain’s interest in space, increasingly, narrowed to communications and navigation satellites, to support the complex chain of shipping services that fed raw materials into the United Kingdom from distant lands (particularly the Middle East). West Germany, for its part, was most interested in all manner of space science--heliophysics, astronomy, planetary science, and materials science in microgravity. The Federal Republic of Germany took a prominent role in ELDO’s counterpart, the European Space Research Organization (ESRO), and developed, in partnership with NASA, the Helios spacecraft, which would study the sun at an unprecedentedly close range. As the 1970s dawned, ESRO would lay the foundations, with NASA, for the later Spacelab program.

    Europe’s scientific triumphs in space were still years off, however, when ELDO’s Europa rocket failed on every attempt to successfully orbit a satellite. Though the British-made Blue Streak first stage did its job well on the first-stage-only flights and on the later tests with the complete vehicle, the upper stages, manufactured in France and West Germany, failed, over and over. The nations involved took these failures in different ways. Britain’s Labour government had already reduced their commitment to the project; the repeated failure of Europa led to their total withdrawal. Though Britain would launch her own satellite on the Black Arrow rocket precisely once, Her Majesty’s government would have no part in space launch after 1971.

    France and Germany had to soldier on without Perfidious Albion. The failure of Europa and the loss of its first stage forced a total redesign of ELDO’s launch vehicle. ELDO’s engineers formed two general camps. One of these camps, taking their cue from the trend toward reusable rockets in the United States, advocated a system much like a miniature Space Transportation System--a one-man piloted first stage with an expendable second stage. As France had already committed to developing a hydrogen-burning rocket and the new vehicle would have no heritage to which it had to cling, it could be optimized early on to burn the high-performance hydrogen-oxygen combination, managing a better mass fraction than the STS was to have. They dubbed their proposal “Europa L3R,” or “Europa Lanceur 3, Réutilisable.” The second camp was more conservative. Pointing out that reusability’s economic case had not yet been proven, and noting the limited resources of the European aerospace sector compared to the gigantic American war machine (and, not so loudly, that ELDO had yet to demonstrate the ability to go up, let alone down), this second camp favored a derivative of France’s Diamant hypergolic rockets. Diamant, as a satellite launcher, had been fairly successful, and as West Germany too seemed to gradually lose interest in ELDO, its all-French heritage was a welcome safety measure for the program. A new rocket, originally named “Europa L3S,” (Europa Lanceur 3, Substitution--for its replacement of the first stage) was designed around a new, higher-performance hypergolic engine called Viking, and a hydrogen-burning engine derived from France’s HM4.

    Ultimately, Europa L3S triumphed over the L3R because of its lower development cost. As much as France strove to continue playing the part of a Great Power in a bipolar world, its resources were simply not nearly as large as those available to the United States and Soviet Union. The economic case for L3R made more sense, in the long run, than that for Europa, but having a run at all was only possible for Europa L3S.

    Europa L3S, eventually to be renamed “Ariane,” promised the ability to loft commercial payloads to geostationary orbit. But by the time the program was announced, in 1973, this was a capability of interest only to France. Britain’s space ambitions had converged on a maritime communications and navigation constellation, while West Germany was in negotiations with the US to build the Spacelab man-tended space station. The original goal of the Europa program, to break the American monopoly on communications satellites, had been all but forgotten.

    Eventually, a deal was hammered out between Britain, France, and West Germany, where each would support the others in achieving their goals. Britain would have her communications/navigation constellation, West Germany would have Spacelab and a growing fleet of scientific space probes, and France would have Ariane. Italy, the Netherlands, and Belgium would see continued economic support for their burgeoning space sectors, and ELDO and ESRO were to merge into a new organization--a European Space Agency--by 1975.

    Ariane was scheduled to be completed in 1979--the same year for which the Space Transportation System’s debut was planned. Ariane was a conservative gamble--a pessimistic one--in that it assumed that reusability would be far more expensive than the Americans predicted, that the satellite market would not grow fast enough to demand the two dozen flights per year that the Americans forecasted, and that a small launcher produced in limited numbers would be able, economically, to hold its own against the American vehicle. While the French had no illusions about capturing all the world’s commercial satellites, they believed Ariane’s cost would be competitive with that of the much more complicated STS. Given these assumptions, the ability to ensure a European launcher for European institutional launches was viewed as worthwhile, even if it was slightly more expensive than STS.

    EDIT: Points to TimothyC for spotting a minor continuity error about the airbreathing engine count early in this post.
     
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    Chapter 7: Max-Q
  • “If you have a 65,000-lb manned scientific laboratory to place in low Earth orbit, then the Lifter is just the job. But if you have a 1,000-lb communications satellite bound for stationary orbit (and paid for by the shareholders), a good old-fashioned rocket will do the job at half the cost.”

    Chapter 7: Max-Q

    Twenty seconds after liftoff, the stack climbed into the skies above Florida. As the delta-winged stack climbed, the Earth made one last effort to hold it back. Its own speed now conspired against it. As the rocket pushed its way through Earth’s thick atmosphere, breaking the speed of sound and leaving its own roar behind, it squeezed the air in front of it far above ambient pressure. Constitution’s five F-1B engines automatically throttled back as the stack approached the region where the atmosphere and its speed would produce Max-Q: the peak of aerodynamic stresses on the rocket. Throttling back slowed the ascent, introducing losses just as drag increased, but the larger worry was the forces on the Lifter and the Orbiter as the dynamic pressure climbed to more than three times that at sea level. The stack shook as the atmosphere buffeted the rocket.

    The pressure was intense, and every eye at mission control watched the data for any sign of failure in these critical moments. As the stack pushed closer to Max-Q, the pressure was enough to condense water from vapor to liquid, forming opaque discs around the base of the Orbiter and alongside its control surfaces. Briefly, the Orbiter once again vanished from the Lifter crew’s view as a cloud developed around its base, around the complex interface between its aft end and the S-IVC. For the complete Space Transportation System, this was a moment of truth: would the models developed in aerodynamic trials on the ground hold through the test of reality?

    The pressure data in the telemetry and the gauges of the stack’s two cockpits climbed, then steadied...and then finally began to drop. The shock cloud evaporated, and seemingly instantly the ride smoothed out. With more than half the mass of Earth’s blanket of air behind them, Constitution’s engines once again spun up to full power.

    “Houston, Constitution,” John Young called over the radio, ”Go at throttle up!!” The stack had cleared the test of Max-Q, the pressure was falling, and all systems remained nominal. Downrange, there was only the blue of the sky above, and the blue of the sea below. The stack cut through it like a knife, a delta-winged dart breaking trail for a tail of flame which now spread in the less dense air to several times the ship’s wingspan. Space lay ahead.


    The official certification of the Space Lifter as “operational” came as a relief to the thousands of people both at NASA and at innumerable contractors who had poured almost a decade in turning the concept of a reusable space launch system from a dream of s-f magazine covers into a real, working system. The Space Lifter and the Space Shuttle were the first of a new breed of launchers designed to go to space not once but dozens of times, and to open up a new era of space development. The three operational RS-IC boosters had already demonstrated their reusability, with Independence and Constitution both having completed 8 orbital launch missions by the time STS-8 had returned from orbit. Endeavour’s came, of course, after that debut mission, with the orbiter returning to space next eight months later. The dreams of Von Braun and others of orbital ferries had been realized in some form. However, while the pressure of development abated, the pressure of the program’s own inertia and of the expectations of the newly “operational” system built up, and only raised the stakes. The moment of maximum program pressure still lay ahead. For STS to be a success, Shuttle and Lifter would have to prove that they could indeed not just fly repeatedly, but also cheaply, rapidly, and safely. While doing so they would be able to satisfy the needs of the many customers whose buy-in NASA had secured with promises about the Space Transportation System’s capabilities.

    These promises had yielded an impressive backlog of missions for the Space Lifter. The first half of 1980 had already seen two completely commercially-driven missions using the Space Lifter’s Multiple Launch Adaptor to place payloads on their way to geostationary orbit. Following STS-8, there were two more such flights on the year’s manifest. As with the earlier missions, the payloads were undersized for the LIfter, even with multiple launch capacity, totalling less than a third of the vehicle’s geostationary transfer payload. Satellite buyers were still waiting to see if Lifter’s promised cost reductions and flight rate would be sustainable before purchasing any satellite which couldn’t be flown on other systems. Until then, Lifter’s true commercial potential would go unrealized. Still, every successful launch seemed to encourage two new bookings, and as Lifter racked up a successful record, customers we more willing to consider busses which were--technically--launchable on other launchers, even if those launchers were large enough and costly enough to be prohibitive as anything other than a fallback. Hughes had been doing booming business in their HS-376 bus, which had a mass of just over a ton at separation, and which had been the first commercial payload on the Space Lifter. By 1982, Hughes was working on a backlog of more than a dozen orders for the platform, and sold eight more in that year alone. They also took a risk, working with Intelsat to develop a new satellite bus which would mass more than four metric tons at separation. It was, at least nominally, capable of being lofted by alternate vehicles like Titan or evolved Ariane derivatives, but the main launch plan would be Space Lifter--which could accommodate two such monster satellites comfortably in the same flight. The satellite, and others like it offered by competing firms, were larger and more capable than any planned for geostationary use before--indeed, they could accommodate more mass in communications equipment and antenna than the entire fueled weight of some previous-generation commercial busses. Though Intelsat and Hughes had been the first to fully commit to such capable busses, they wouldn’t be the last, and some designers had tossed around the potential for what could be done with a full Lifter launch. Such build orders and discussions ultimately lead these builders and customers to turn up the pressure on NASA to deliver reliable launches on tempo, and Space Lifter would have to push on and deliver.

    While the Space Lifter made regular launches of commercial and governmental payloads, the Space Shuttle orbiter was still in its test phase throughout 1981 and 1982. For all the that entire Space Transportation System had been declared officially “operational” after its first flight of Lifter and Glider together on STS-8, Shuttle itself had many more capabilities to shake down. The first flight had been focused on proving the basic functionality of the vehicle: reaching orbit, opening the payload bay doors, deploying the Canadarm robotic arm, and communicating with the ground via TDRS. However, the next Shuttle flight would take more than 6 months to occur, as engineers and technicians crawled all over and through Endeavour, reviewing the effects of the flight on her structures and systems. The information was filtered back to the construction bays at Palmdale, where two more Orbiters were taking shape. In the meantime, Endeavour took flight once more atop the booster Intrepid for the STS-12 mission.

    The glider’s second mission was, in some ways, an extension of the first.readied again for her second flight. While STS-8 had stuck steadfast to the most basic capabilities of the orbiter, staying up for only a day, STS-12 was a more comprehensive test of the orbiter’s capabilities. The crew was still limited to the commander and co-pilot, but the mission duration was extended to a five-day flight--less than the shuttle’s maximum endurance even with a full crew, but offering much more time for the crew to test the ship’s systems. While Fred Haise and Richard Truly had tested the basic motion of the Canadarm on STS-8, and used it to conduct basic inspection of the ship’s thermal protection tiles, STS-12 saw Ken Mattingly execute several more detailed tests of the arm’s manipulator abilities in space, unlatching and repositioning a test payload within the shuttle’s cargo bay. That test payload wasn’t alone; while STS-8 had flown empty, the bay on STS-12 carried several scientific and engineering payloads. Most valuable were a bank of earth-sensing instrument pallets presented with a perfect chance to do their task by opening the shuttle’s cargo bay doors and rolling the bay to face the Earth, then being returned to the surface. Even her descent offered a chance to push the edges of the envelope STS-8 had carefully shied away from: while STS-8 had made an automated descent carefully plotted down the middle of every band engineers could design her for in the tempest of entry, Mattingly took a manual hand on the stick in STS-12’s descent, guiding Endeavour through more aggressive maneuvers as she returned to Earth. These twists and turns tested the spacecraft’s ability to maneuver at hypersonic speeds in the rarified upper atmosphere and exposing special sensor pods on the glider’s tails to new engineering regimes. Endeavour marked her return to Earth with a bang, leaving a cone of her lifting body shape’s characteristic sonic booms as she glided to a landing at the Cape, with Mattingly putting her down within three inches of the runway centerline. Though other reusable had flown to the edge of space, Endeavour now proved she was the first truly reusable orbital spacecraft.

    These patterns of expanding envelopes followed on the next Shuttle mission, this time on STS-15 in July 1981. Endeavour rode to orbit on yet a third booster, the debut launch of the brand-new Liberty. The flight once again pushed the duration, extending to a full week in space, and for the first time active experiments were carried inside the Shuttle’s cabin for the crew to work on during the flight. However, that crew was still limited to two, and their time was constrained both by the pre-planned tests of the Shuttle’s orbital maneuvering abilities, as well as by a serious failure in the Shuttle’s hygiene facilities, and particularly its orbital toilet. Though the issues with the system’s flush apparatus lead to several colorful exchanges with engineers on the ground, the crew dealt with the other minor issues on the flight, such as overheating in one of the spacecraft’s auxiliary power units, and made a nominal return. Due to the vagaries of the Space Transportation System’s schedule, the final test mission came four months later. Though Endeavour was ready in three, a delayed communications satellite mission prevented the originally scheduled launch date from being met. This mission saw the Shuttle finish off a round of the Lifter fleet, flying on the newly refurbished Independence in early November. The STS-18 mission largely duplicated STS-15, matching it in duration and scope. However, for the first time, the orbiter deployed a payload--a small classified Department of Defense satellite--from the payload bay with the aid of the Canadarm. On her return, Endeavour conducted her most sweeping in-atmospheric maneuvers yet, continuing to prove that the orbiter had the cross-range capabilities required to return to land following a one-orbit mission to polar orbit from Vandenberg--a capability of interest not only to the DoD, but for a single-orbit “Once Around” abort of any mission to that orbit. Upon Endeavour’s latest return to Earth, President Reagan sought his own chance to leave a mark on the space shuttle program. While Carter had commemorated STS-8 by marking the operational status of the Space Lifter, Reagan now met Endeavour at Edwards Air Force Base in the President’s home state of California, and officially announced that the Space Shuttle was now operational--and with it the entire Space Transportation System.

    Following its proving-out missions, the Space Shuttle faced the challenge of operational missions. While the glider’s development had been delayed, missions hoping to make use of the orbiter had been building up a manifest, and with Endeavour and her (yet unfinished) sisters commissioned as operational, the pressure to start accomplishing these task only increased. Over her next three missions, Endeavour put her capabilities to the test. Though the airlock had been cycled in space on test missions, STS-21 in February 1982 brought the first EVA from the Space Shuttle, enabled largely by the first four-person crew, featuring not just pilots by two mission specialists. The task they faced on this flight was another milestone: the deployment of the Long Duration Exposed Facility (LDEF) from the cargo bay. The LDEF was a pallet of experiments on biology, physics, and materials. Its launch on Endeavour was planned to be followed by return on another Shuttle mission in a year, with subsequent reflight of slightly altered platforms to follow. STS-21 was not just the largest crew ever launched by the United States, but the most diverse to that date. Copilot Guion Bluford became the first African American to fly in space (though not the first black man, a milestone claimed by the Soviet Union with the launch of Cuban cosmonaut Arnaldo Mendez in 1980), while Judith Resnick, as the mission specialist in charge of operating the Canadarm and deploying the LDEF, became the first American woman in space.

    It is worth mentioning, in the context of the Cold War propaganda struggle, that the Soviet Union answered Resnick’s flight by launching the woman cosmonaut Svetlana Savitskaya on the Salyut 7 mission just weeks later. During her 3-week flight, Savitskaya became the first woman to perform an Extra-Vehicular Activity, and the second Soviet woman in space. Unfortunately, she would also be the last Soviet woman in space, as the Soviet cosmonaut corps was generally hostile to women cosmonauts. As Professor Anatoliy Grigoryev remarked after 1991, when he was named Director of the Institute of Medical and Biological Problems, “women are fragile and delicate creatures; that is why men should lead the way to distant planets and carry women there in their strong hands.”

    Other Shuttle payloads required less handling: on STS-24 in June, Endeavour’s crew began their mission with the deployment of a small geostationary orbit satellite, attached to a compact solid rocket motor to perform apogee raise to a traditional GTO after deployment. This package, intended for satellites massing 600 kg or less, was an option developed by NASA for satellites which were too small to effectively utilize even a slot on the STS Multiple Launch Adaptor. While such payloads couldn’t justify even half the cost of an STS launch, these “fire-and-forget” GTO deployments from the Space Shuttle’s bay were subsidized by the NASA missions they flew with, and thus were available at lower cost--though with less opportunity. It was another example of the pressure NASA was under to develop ways to maximize revenue from the STS, both Lifter and Shuttle, and offer as much capability to American and international customers as possible.

    The STS-24 primary mission objective was a demonstration of an even more important capability: the orbital repair of a damaged satellite to return it to operational service. The Solar Maximum Mission was a NASA scientific spacecraft which had been launched two years prior to study the sun and its cycles. However, just nine months into its mission, the failure of half the fuses in its attitude control system limited the spacecraft to operating just three of its seven primary instruments. However, the spacecraft had been designed with a grapple fixture for the Space Shuttle robotic arm, and STS-24 was assigned the task of directly intervening to restore the satellite to full function. The task was not simple: undocumented modifications in production not reflected in the plans meant that the shuttle could not use the original planned maneuvers to stabilize the spinning spacecraft. In the end, the only option was for an astronaut to grab onto the spacecraft’s delicate solar array and apply torque with his MMU to stabilize the spacecraft-risking tearing the array off entirely. The approach worked, though not without a failed attempt which almost doomed the spacecraft entirely before the ground and the astronauts could prepare for a second attempt. Once the satellite was stabilized and grappled, the mission proceeded more to plan. The entire suspect attitude control system was removed and replaced and upgrades were made to the spacecraft’s suite of scientific equipment, replacing one instrument and modifying another. By the end of the mission, not only had the spacecraft’s function been restored, but it was more capable than it had been at launch two years earlier. This example, carried out on a spacecraft only obliquely intended for in-space servicing, was a powerful demonstration for future spacecraft which might depend on such tending--and of the considerations for rendezvous, grapple, and orbital maintenance which must be accounted for. It was watched with interest not only by major programs within NASA which were built around this capacity, like the Large Space Telescope and Spacelab, but also by more classified projects under the aegis of the USAF.

    While the Space Shuttle was proving out its basic capabilities, the Space Lifter was facing the pressure of demonstrating its full promised capacities as launch rate ramped up to meet the demands--and the optimistic projects NASA had made to sell the system’s development. In 1977, the Lifter’s booster had debuted with a single suborbital test. The next year had seen three more suborbital test flights, plus a qualification flight of an active upper stage and mass simulator. Topping this, 1979 had seen four orbital flights, then 1980 had seen six. Faced with increasing demand for launches from commercial satellite operators, the Department of Defense, and the addition of the Space Shuttle, subsequent years called for every year to exceed the previous year by at least two launches a year. A launch rate of one per month every month was called for no later than 1983. Considering the usual issues with operating any new program, not to mention the complexities of scheduling rockets around customer demand, contractors and suppliers, weather, and NASA’s own internal schedule priorities, this was ambitious, but the efforts to avoid slipping schedules were complicated by scheduled SLIP: the Spacecraft Lifespan Investigation Program.

    The Space Lifter’s RS-IC booster was designed for a long, effectively unlimited lifespan per vehicle, with rapid and cost-effective turnaround between flights. The hope was that a mature booster program would be capable of turning a booster around in as little as a week, hopefully with little more inspection or overhaul than a high performance military aircraft. NASA knew that this was an optimistic goal, and had no experience with operating a reusable suborbital spacecraft of this scale for so many flights. Ground tests had validated thermal protection systems, engines, and the airframe and tanks for dozens or more cycles. However, it remained to be seen how closely the Lifter booster would align with those test results in service. Inspections to determine the alignment would require sacrifices which would make NASA’s goal of rapid reflight challenging if not impossible: crawling over every inch of vehicle, inside and out, on every flight. Drawing on the example of continuous aircraft maintenance programs for commercial and military aviation, SLIP would consist of varying levels of checks, with increasing levels of rigor, conducted at scheduled intervals. Some checks and maintenance would be carried out every flight during routine turnaround, such as basic computer checks, visual inspection of external surfaces, and the functionality and condition of critical primary and secondary systems. Others were scheduled in alternating combinations every second flight or on similar intermittent schedules, such as borescoping the F-1B turbopumps. However, at scheduled milestones, each airframe in turn would face a SLIP inspection of similar scope to an aircraft “D” check: a near complete inspection of every component in every detail, including substantial removal and replacement of components.

    Though much of these SLIP checks had been part of the experimental test program prior to the first orbital flight, the first milestone for “operational” SLIP inspection was six flights into the boosters’ lives. Though some of these checks had been conducted after every early flight, the first major check was scheduled to follow the sixth mission for each booster. Until these heavy inspections and overhauls were completed, the boosters wouldn’t return to the flight line. Independance was the first to hit her maintenance interval, being moved off the active list following her sixth flight to launch STS-6 in April 1980. Constitution followed in turn after STS-8. During this overhaul, the boosters departed from the Cape, ferrying back to their construction sites for inspection more intense than could be managed in the booster processing facilities at Kennedy. Many of the same engineers and technicians who had originally built them now crawled all over their charges for months on end. The boosters’ main engines and its hydrogen peroxide thrusters were safed and removed, enabling inspection of the entire systems. The ten airbreathing engines were removed as well, and their hydrogen peroxide start turbines were inspected as well for erosion or damage. Portion of the boosters’ propellant feed lines were removed and replaced, with the old ones sent to but cut up for metallurgical testing. The entire cockpit ejection pod was removed from each booster for the first time. Pyros and solid ejection motors were removed, replaced, and the old ones tested. Sections of the boosters’ titanium and aluminum heat shield were removed for similar tests, and the entire boosters’ protective coatings were stripped to enable inspection of the skin itself inside and out. Every possible wire in the vehicle was tested at both ends to ensure proper signals, and sensors were removed and tested. While the inspections went on, any defects were catalogued and repaired, building a picture for how the two boosters had aged in service.

    Overall, the issues found by inspections of the Lifters, at least, were minor and in line with what had been expected based on the ground tests and turnaround checks between missions. While the repairs were made, a few minor improvements were incorporated based on the experiences of the initial years of flights and development in the meantime. The most important were minor upgrades to the booster’s computer systems, but the most visible was to the boosters’ appearance. Independence and Constitution had originally been painted a clean white, intended to enable easier evaluation of potential damage to the coating or the all-important aluminum and titanium skin behind it. However, in service, the benefits of this visual inspection had been found to be biased by pure surface discoloration from the high temperatures encountered during booster entry and discoloration from previous flights if the booster wasn’t laboriously washed between missions. New non-destructive evaluation methods were also introduced to supplement and even replace the pure visual evaluation. Thus, when Intrepid had received her Air Force paint job, she had been colored a light gray on her top surfaces, and black on the belly, which had proved after STS-7 to show much less visual change between flights. While Intrepid still needed to be cleaned between flights to remove the worst of the charring, this could be done with essentially an oversize car wash, and removing non critical but heavily visible char no longer required as much labor. Thus, when Independence and Constitution received a clean bill of health to return to the flight line for another dozen missions each, they would wear the same paint job.

    While the pressure was on SLIP to prove that NASA had achieved its goal of a heavily reusable booster, the absence of two of the three operational RS-ICs from the Cape left the pressure of the entire launch program to be borne by Intrepid alone. The program’s ability to meet its high-pressure schedule goals through the end of 1980 and early 1981 would depend largely on their ability to prepare a single booster for reflight. As soon as Intrepid returned from launching a pair of commercial communications satellite on STS-9 in September, crews set to work to ready her for a Department of Defense payload to be launched on a dog-leg polar trajectory in November. With this classified payload (in fact, the final KH-11 optical spy satellites) deposited into LEO, Intrepid was turned around for a January launch of another pair of comsats on STS-11, before finally launching the Space Shuttle Endeavour’s second flight to orbit on STS-12 in March. While the two-month durations between missions weren’t a severe trial of the turnaround that Lifter could manage, the effects meant that delays in preparing any one missions cascaded directly onto the next--there was no second booster stacking in the VAB while Intrepid waited for launch windows to open up in wind and weather. It made the one-month turnaround achieved between STS-12 and STS-13 in April all the more impressive, especially given the debut of the new Centaur-G stage used on the launch of the DoD Chalet satellite to geostationary orbit as preparation for future NASA use of the stage for interplanetary flights.

    The Boosters were not the only vehicles caught up in SLIP schedules. Following STS-24 and her sixth launch, Endeavour was removed from service for her own SLIP-I inspection, and a similar in-depth inspection was conducted. In addition to her usual post-flight OMS inspection, her abort engine system was removed and the modified LR-91 engines inspected. During her absence, the second NASA Orbiter, OV-103 Discovery, replaced her for further flights, with her maiden flight on STS-27 in October.

    Between SLIP inspections and Intrepid’s marathon run bearing the entire launch manifest for STS, the Space Lifter booster was proving its value. Though the cost per flight of a Space Lifter mission was above $40 million instead of the $18.5 million originally promised in 1971, this was actually to slightly lower than the original estimates when accounting for inflation. However, there was still pressure to further reduce costs, and much of this focus turned to the major expendable portion of the system: the S-IVC stage. More than half the cost of each flight was in the structures of the S-IVC, disposable interstage, and launch fairings, with another substantial portion being the J-2S-2 engine, while the production rate of S-IVC stages was projected to potentially be the limiting factor in STS operations if a fleet of four boosters (including booster RS-IC-604 Liberty which was completing testing prior to delivery) were each capable of launching once a month. While reducing booster turnaround costs could help in boosting flight rate, the production of upper stages was the main target for pressure for program cost reduction and production throughput increases. McDonnell was challenged on whether the rate of production and cost of each stage could be increased by further automation, while process engineers worked through every step to minimize delays, increase utilization of fixed-overhead equipment, and reduce manual labor.

    Additional benefits came as McDonnell would no longer acceptance fire each stage as a unit. Instead, Rocketdyne’s acceptance firings of each engine would be used to qualify a lot, which would be delivered for assembly. After assembly, a wet dress rehearsal of the stage would test and qualify the stage’s structures and plumbing, but the SACTO test site would be mothballed, as there were no further plans for static-fires of complete S-IVC stages. The results helped stem the growth of operational costs, but involved accepting a certain degree more risk. Even as engineers fought to achieve further cost reductions, they were developing confidence in their product as production fell into a rhythm. The S-IV had already passed the flight history of the 200 series and 500 series of the S-IVB, not to mention the original S-IV, and was on track to pass the combined production of the S-IVB 200 and 500 series by the end of 1982. As the peak pressure bore down on the STS program to deliver flights, reduce costs, and launch critical payloads, the work of engineers to ensure the ongoing supply of S-IVC stages was little more than a footnote.

    While the launch portions of the Space Transportation System was focusing on bearing up under the rising pressure of operational missions, NASA attention was focused on the high-profile internal programs which Space Lifter and Space Shuttle would enable. The largest for NASA’s human spaceflight program was the Spacelab man-tended platform. The Spacelab program can trace its origins to the cooperation agreements between the European Space Research Organization (ESRO) and NASA, beginning in the late 1960s and escalating under the Nixon Administration. In 1970, NASA Administrator Tom Paine briefed ESRO managers on his expansive vision for NASA’s post-Apollo goals--a fleet of space stations in orbits from LEO to the Moon, a swarm of space tugs moving payloads to and fro between them, a fully-reusable Space Shuttle to launch all of it from the ground, and, as the cherry on the stacked cake, crewed voyages to Mars and even beyond. Of most interest to ESRO, which had achieved some success building scientific satellites, were the space stations. The industrial applications of high-molecular-mass crystal growth and microgravity manufacturing techniques offered the chance for medium-term return-on-investment, a stimulus for the European manufacturing and pharmaceutical sectors (particularly that in West Germany). As the US government made it clear that the proposed Space Tugs could not be outsourced to Europe (due primarily to concerns about sharing cryogenic rocket technology), ESRO concentrated its attention on European participation in the Space Station projects.

    Though both ESRO and NASA were in agreement that they wanted to work on a Space Station in the near future, the two agencies brought to the table very different assumptions about the actual purpose of the station. Indeed, even within NASA, there was, until 1973, no clear consensus on just what the station would be for. Marshall Space Flight Center, still under the spiritual (if not actual) leadership of Wernher von Braun and his German team, envisioned an orbital shipyard, propellant depot, and manufacturing facility where ships and satellites were assembled and refueled for journeys further out into space. Such facilities would be necessary for the realization of the voyages to Mars that von Braun had envisioned decades before--only in the wide expanses of space could the vast landing craft and spinning, nuclear-powered interplanetary ships be assembled. Johnson Space Center, for its part, shared the belief that the Space Station’s purpose was to support longer-term human exploration of space, but envisioned the Space Station as essentially a test article for an interplanetary ship--a proving ground for advanced life-support systems, with the ultimate goal of complete life-support system closure. For their parts, the scientists from Goddard, Ames, and Lewis Research Centers all had different focuses within the broad umbrella of “space science,” and while they generally envisioned smaller vehicles, they differed on the subject of where a space station should go, whether it should be permanently manned (or manned at all, as a persistent minority at the Jet Propulsion Laboratory kept asking), and how much human intervention in the experiments was actually required.

    It was somewhat fortunate for ESRO, then, that the Nixon Administration was considerably less ambitious with regard to spaceflight than Administrator Paine had hoped. By 1971, the administration had made clear that NASA’s budget would not be nearly large enough to afford the interplanetary empire Paine had described to the Europeans. Instead, the agency would have to pick the element of the system it found most useful--the Space Transportation System, the combination of Lifter, Orbiter, and disposable second stage.

    The cancellation of plans for the permanent Space Station, however, did not end all discussion of human-operated experimental platforms. The Orbiter proposed for the Space Shuttle system was to have an on-orbit lifetime at least several days long and enough payload capacity to carry out scientific experiments on-orbit. Program managers proposed to add to this capability by installing a reusable laboratory module, which could be carried in the payload bay. This “Sortie Can” attracted some interest on both sides of the Atlantic--Grumman Aerospace went as far as recycling some of its Lunar Module Laboratory (LM Lab) concepts, initially developed for the Apollo Applications Program, into proposals for a Sortie Can. The concept was particularly popular at Ames Research Center, whose experience with the flying Galileo laboratory (carried inside a modified Convair 990) illustrated the flexibility and utility of a frequently-flying multi-instrument platform. However, as the limitations of the Orbiter’s consumables, electricity, and payload capacity became clear, attention shifted from the Sortie Can to a proposal that originated in Europe, initially termed the Man-Tended Free Flyer.

    In its scale, Man-Tended Free Flyer was much closer to Skylab than the Lunar Module Laboratory. The new proposal envisioned a 30-tonne pressurized Laboratory Module attached to a 10-tonne Service Module that could provide 25 kilowatts of electricity. The Laboratory Module would host experiment racks for a host of different microgravity science experiments, and external attachment points for materials science investigations in the hard-vacuum, high-radiation environment of outer space. The Laboratory Module’s life support system would be developed by ESA, with some American input. As MTFF missions would be limited initially by the orbital lifetime of the Orbiter, the life support system was optimized to support a crew for up to one month at a time, with most of the actual consumables for the stay (water, oxygen, food) carried by the Orbiter. In essence, MTFF would serve as a cabin in orbit, with a stay time dictated by how much food, water, and power the Orbiter could carry up to it. In order to overcome the limits of the Orbiter’s planned 7-day lifespan, the Service Module would be capable of providing electrical power to the Orbiter, extending the small craft’s lifetime from a week to a month or more.

    The Man-Tended Free Flyer was attractive to scientists in Europe and in some of the American space centers, but not all. By excising the closed life-support system, the MTFF became incompatible with Johnson Space Center’s vision for space stations, and its utility for on-orbit construction was also limited (but not zero--small-scale experiments with assembly and manufacturing in microgravity and hard vacuum could be performed). The vehicle could have been placed in a polar orbit, but this was not ideal, as it would limit the amount of payload that an Orbiter could take up to it. Orbits from 23 to 52 degrees in inclination were discussed, though only the upper ranges satisfied earth science specialists. Physicists and astronomers in both Europe and America were the most hostile to MTFF, considering it a distraction and diversion of funding from unmanned spacecraft, including NASA’s then in-development Space Telescope. Ultimately, however, the program benefitted from the fact that it was essentially a European enterprise--a program run by Europeans did not need to satisfy every lobby in America. Though NASA had taken a new look at MTFF in 1972 (as part of a directive from the President to tie America’s allies more closely into its achievements in space), the program could only be brought to fruition if it were managed primarily from Europe.

    What remained in 1973, then, was the question of how to actually fund and authorize the MTFF. West Germany and its supporting countries in ESRO (Belgium, the Netherlands, Luxembourg, and Italy) remained very interested in developing MTFF, as visions of wonder-drugs and miracle-metals danced in front of their eyes. France and the United Kingdom, however, had differing priorities. After the Europa debacle, France wanted to recommit Europe to a new launch vehicle program, to ensure independent access to space communications for Europe and independence from the American Intelsat monopoly. Britain, for its part, was most interested in a maritime communications network to support its still-significant economic ties to its former colonies. The compromise between the three blocs, signed in 1973, to take effect in 1975, secured each of these programs, assuring each European contributor that its support would be rewarded by support for its own preferred program. ESRO and ELDO were to be merged into a new European Space Agency, which would develop Ariane, MTFF, and the new maritime communications network (though this last would eventually be spun off into INMARSAT).

    ESRO awarded the prime contract for the development of the MTFF, which had been dubbed Spacelab by the Americans and those Europeans who worked most closely with them, to the West German consortium ERNO, a joint venture of Weser Flugzeugbau and Focke-Wulf. ERNO would be tasked with building the Laboratory Module, Exposure Facilities, and Service Module for Spacelab, though they would receive advice and support from NASA’s Marshall Space Flight Center on the Service Module (drawing on that center’s experience developing Skylab) and Ames Research Center on the Laboratory module (drawing on that center’s experience with the Galileo flying laboratory). After the spacecraft was completed and launched, it would be controlled primarily from the European Space Operations Center in Darmstadt, Germany, though the American experimental pallets would be controlled from Ames (in coordination with Darmstadt), and visiting Space Shuttles would, of course, be under the control of Johnson Space Center.

    The Space Transportation System was always intended to become NASA’s primary launch vehicle for all payloads, including those managed by the Jet Propulsion Laboratory and Goddard Space Flight Center for planetary science, astronomy, and heliophysics. For such missions, NASA turned to the venerable Centaur upper stage, which had been the agency’s first vehicle to burn cryogenic hydrogen and which remained the upper stage of choice for scientific and unmanned payloads. Managed by Lewis Research Center and manufactured by General Dynamics, the Centaur had proven its worth as an upper stage for the Atlas rocket, boosting that vehicle’s geostationary transfer orbit payload and turning a first-generation ICBM into a reliable and high-performance launcher for commercial and government payloads. As interplanetary payloads increased in mass, it had also proven very adaptable, moving from the Atlas launcher to a Titan III. Centaur had launched the Pioneer spacecraft to the outer solar system, the Surveyor spacecraft to the Moon, and the Mariner spacecraft to Mercury, Venus, and Mars--though there was some protest from the USAF in favor of a solid-propellant Inertial Upper Stage (so favored for its perceived adaptability to different payload sizes and the reliability of solid rockets) for GTO and interplanetary payloads, the performance of cryogenic hydrogen and the fact that Centaur was already available meant that the debate was brief and Lewis Research Center began work in 1975 on a scaled-up Centaur-G upper stage to fly on the Space Lifter.

    The primary difference between Centaur-G and the earlier Centaurs that had flown on Atlas and Titan IIIE was its diameter. In order to take advantage of the greater diameter of the Space Lifter’s upper stage, Centaur-G’s hydrogen tank diameter was increased 60%, from the original 10 feet to 16 feet, while the length fell from 31.5 feet to 20 feet. Though Lewis Research Center and GD both also proposed even larger Super Centaurs with lengths restored to the original 31.5 feet and even beyond, for super-sized outer solar system payloads, the stubby Centaur-G was deemed by NASA headquarters and the USAF to be sufficient for the near-term needs of both organizations.

    Centaur-G’s first test flight came on April 6, 1981. The payload was managed by the Department of Defense, and remains mostly classified, but a general consensus has emerged that it boosted an electronic intelligence payload to Geostationary Orbit, after which the Centaur-G demonstrated other new features that had been integrated into the design: an increase in multilayer insulation that reduced the propellant boiloff rate from 2% to under 1% of loaded propellant per day, and an optional solar array that extended the stage’s useful life from mere hours to several days. The Lifter-Centaur stack was drastically overpowered for this particular payload, so the Centaur-G retained a significant load of both liquid hydrogen and liquid oxygen after injecting the payload. The earlier Centaur had demonstrated the ability to restart its engines up to seven times, with a coast period over 5 hours long between burns. The upgraded Centaur-G duplicated that coast time, restarting at 300 kilometers above Earth’s surface after circularizing the payload’s orbit and then dropping itself back down toward Earth. The stage and its propellant load were monitored in Low Earth Orbit for another 72 hours before the engines were lit one last time to fully de-orbit the Centaur. Though not strictly necessary for the success of the primary mission, this test of the Centaur-G’s long lifetime and multiple-restart capability was a helpful demonstrator for NASA’s long-term plans to introduce a fully-reusable space tug and to use Centaur-G as the basis for a Service Module to increase the utility of the Orbiter on more complex LEO missions.

    The major successes of the transition of the Space Transportation System from a development and test program to an operational launcher and orbital spacecraft came in spite of some serious shakeups on the ground in the team responsible for the manufacture and preparations of the vehicles. The Space Transportation System involved three prime contractors, three major government agencies (NASA, the FAA, and the USAF), and a host of subcontractors, launching payloads that varied in everything from size to security classification to launch window tolerance. The Reagan Administration analyzed a number of different approaches for consolidating management of the program, including keeping the program under NASA management (an option disliked by the USAF, which wanted to manage its own Lifter and Shuttle fleet), creating a new government agency or corporation (disliked by the Administration, which had campaigned on the promise of curbing the size and scope of government and controlling the proliferation of agencies), and creating a new Government or Private corporation. Ultimately, the option chosen was to have Boeing and McDonnell-Douglas create a new joint venture--the Space Transportation Corporation--that would consolidate all Space Lifter operations under one roof, and through which all Lifter launches would be contracted. The USAF and NASA would buy launches on the Lifter in essentially the same manner that a government office would ship packages through a cargo airline like Federal Express, though, in the case of the former agency, with considerably more oversight on classified payloads. Orbiter operations, as they had less of a market case and more implications for international diplomacy, would remain under the administration of NASA’s Manned Spacecraft Center and, in later years, the United States Air Force. The STC would have, however, have the option to buy excess capability on Space Shuttle missions back from NASA on a prorated basis for deployments of small “ride-along” comsat deployments from the glider’s payload bay, such as that carried out on STS-15 or STS-24.

    Among other consequences of the creation of the Space Transportation Corporation was the gradual divorce of Marshall Space Flight Center from the day-to-day operation of the Lifter fleet. Though the center remained firmly involved in plans to utilize the Lifter’s capability for NASA’s planned space station, and worked closely with Boeing and McDonnell to iteratively improve the Lifter design in smaller ways, the concentration of STC assets at Michoud Assembly Facility, the West Coast assembly plants owned by the prime contractors, and the launch pads at Cape Canaveral and Vandenberg Air Force Base increasingly meant that Kennedy Space Center took the lead in actual NASA use of the Lifter, handling payload integration and the specialized facilities that NASA had built up for the Apollo Program and converted for use with the Space Transportation System. With the cancellation of the “Shuttle II” design studies and the delivery of the Spacelab service module for final assembly at the Cape, MSFC saw a wind-down of the development work for which it had been founded, and the center would become a major source of lobbying for a plan for a new, major NASA program as the 1980s progressed.

    Though the transition from development to operations did not equally enrich all branches of NASA, and introduced a significant degree of confusion in the first weeks of STC’s existence as the corporate cultures of Boeing and McDonnell-Douglas were forced together, the Space Transportation System seemed well on its way to becoming a successful launch vehicle by 1982. STC won many new communications satellite contracts, and its growing record of reliability inspired mission planners at NASA, commsat manufacturers like Hughes, and the secretive National Reconnaissance Office to begin planning to utilize the full range of the system’s capabilities. Several important institutional payloads planned to use the system were in the final stages of preparation, most critically the European Pressurized Module and the Marshall-built Service Module for Spacelab which arrive at the Cape for final assembly. The boosters Independence and then Constitution returned from their SLIP inspections cleared for another dozen missions each, and the fourth and final booster, Liberty made its debut flight. As the Lifter closed out 1981 with its 8th launch of that year (and 19th overall orbital launch), it seemed that the system’s future was bright and clear. The pressure began to come off even as the launch rate was only set to accelerate.
     
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    Chapter 8: Acceleration
  • “Houston, Endeavour. Payload separation confirmed. We deliver!”

    And they did. Again, and again, and again.


    --NASA PAO Educational Film Strip, 1984


    Chapter 8: Acceleration


    With the stress of Max-Q behind it, the Lifter throttled its five F-1B engines back up to full power, spinning their turbopumps up faster and faster to overcome the phenomenal pressures of the combustion chambers and force more oxygen and kerosene in. Flame fronts and shock waves swirled chaotically within the engine, dissipating almost as quickly as they formed when they encountered the specially-shaped baffles along the inner surfaces, releasing their energy before it built up enough to damage the engines.

    Though a casual observer on the ground might never realize it, the Lifter was not a rigid body, but one that flexed in response to the strains of flight. The force of her five F-1B engines deformed the thrust structure and the propellant feed lines, changing the rates at which propellant flowed. The vibration of the spinning turbopumps propagated across the stack, exciting every component to motion of its own. Aerodynamic stresses and the automatic compensation by the gimballed rocket engines also exerted an uneven force on the booster, causing it to sway, very subtly, back and forth as it rose.

    Within the S-IVC liquid hydrogen tank, a wave began to develop, a rising crest of frothy, boiling cryogenic liquid slowly marching from one side of the tank to the other, altering the vehicle’s center-of-mass as it moved. Unchecked, the wave would have amplified, gathering more and more of the precious fuel into a larger crest, swaying the booster beyond the ability of the gimballed engines to correct. But this was an eventuality for which the engineers on the ground had prepared--the wave crest broke against a perforated baffle, its energy dissipating as noise and much smaller, chaotic waves on the hydrogen’s surface, colliding and amplifying and dissipating one another to nothing, transmitting their mechanical energy into the aluminum tank around them, which, in turn, finally released that energy as an unobservably tiny load of heat, generated by the friction of aluminum plates and struts and bolts against one another, in accordance with the Laws of Thermodynamics.

    The Lifter stack accelerated faster and faster, as its mass decreased and as air resistance became negligible. Acceleration piled into velocity, then cascaded into distance as the stack climbed. Through the supersonic regime, into the hypersonic regime, where the heat of air compression began to dominate the airflow around the booster. Her white paint scorched in places as she ascended, succumbing to the intense heat of air unable to get out of the way in time. Still she soldiered on, her computers compensating for every disturbance to her trajectory within milliseconds, taking the intense loads of flight to orbit, and matching them perfectly.



    Spacelab was finally completed and launched in 1983, by the Lifter Constitution on the STS-35 mission. The Laboratory Module and Service Module were successfully injected into a 50-degree orbit, chosen as a compromise between coverage of Earth’s surface (for downward-pointing earth observation experiments) and ease-of-access from the low-latitude launch sites favored by NASA and ESA. After separating from its S-IVC stage, the Service Module extended its two broad solar wings and radiator panels, and prepared to receive its first crew. Even before their arrival, however, the space station began beaming back valuable scientific data--geiger counters placed at strategic locations within the spacecraft measured the intensity of cosmic radiation penetrating the outer hull and material samples placed inside the Laboratory Module.

    The first crewed mission to Spacelab launched just two weeks later, carrying a crew of six to shake the space station down and perform a variety of scientific experiments during their ten-day stay. The crew checked out the station’s life support system and its ability to provide power to the Orbiter, whose orbital lifetime was ordinarily limited to seven days. Using the Orbiter’s Canadarm, they installed the first External Experiment Pallet on Spacelab’s port side. This first EEP carried a Plasma Diagnostics Package, designed to study the Earth’s ionosphere, and an ESA-developed Instrument Pointing System, designed to improve the tracking capability of Spacelab-mounted observation instruments like solar telescopes and infrared cameras. The PDP would remain on Spacelab for months after the crew returned to Earth, collecting valuable data on the interaction of Earth’s upper atmosphere with ionizing radiation emitted by the Sun. Though this first mission did not demonstrate the full capability of Spacelab, later missions would extend the stay times to two weeks, then three, and finally to 28 days, and carry more advanced instruments and experiment packages.

    The first Spacelab mission, STS-36 aboard the Space Shuttle Discovery, also bears the distinction of carrying the first West German astronaut, Ulf Merbold. The Free World’s answer to East German Sigmund Jahn, Merbold was a specialist in Metals Research, and performed experiments on creating ultra-pure semiconducting materials in microgravity. On the thirteenth day of the flight, he also gave a 20-minute interview for the West German public television channel EDF, facilitated by the growing network of TDRS satellites in geostationary orbit. When the interviewer remarked that he’d spent nearly twice as long in space as Jahn had, Merbold cheerfully replied, "mit dem Zweiten ist man besser," "with the second, one is better," a play on the slogan for West Germany’s public television station.

    The second Spacelab mission, launched in 1984, would operate for 14 days, during which the crew performed a multitude of experiments in microgravity physics, studying fluid slosh, combustion, and the formation of metallic alloys in microgravity. Spacelab 2 also carried the first Japanese astronaut, Mamoru Mohri, a materials science specialist. The third and fourth Spacelab missions, taking advantage of the longer durations, studied the effects of long-term microgravity exposure on humans and other organisms. Though the deleterious effects of microgravity had been well-known since the Gemini program, determining whether artificial gravity was really necessary remained a top NASA priority. As such, Spacelab 3 and Spacelab 4 tested new exercise regimes and dietary supplements designed to reduce bone and muscle loss in the dangerously low-stress environment of Low Earth Orbit.

    The unique experimental opportunities opened by the man-tended Spacelab were demonstrated most dramatically in the interim between Spacelab 4 and Spacelab 5. At the close of the Spacelab 4 mission, the crew left behind an experiment rack developed by Ames Research Center and Johnson Space Center, containing a population of female rats and a supply of food and water. Over the six-month period between Spacelabs 4 and 5, these rats would survive in microgravity, their activities observed by a television camera that beamed signals down to researchers on the ground. Samples of rat urine collected automatically were stored for later analysis, so that hormonal changes in the rats could be studied in greater detail. Though the findings of the experiment matched expectations (the rats displayed a similar decrease in bone and muscle density to humans), the endeavour had proven the utility of the long-term microgravity environment Spacelab offered, and future experiments would take more ambitious steps toward realizing NASA’s goal of a fully-closed life-support system.

    While not the massive orbital shipyard, medical research facility, and laboratory for which NASA had hoped in the early 1970s, Spacelab played a vital role in teaching NASA and the European Space Agency how to live and work in space before committing to such a vast project, and helped integrate the ESA and NASDA more closely with NASA’s human spaceflight programs.

    Spacelab was not the only program to yield good scientific fruit for NASA. The year 1984 saw the inauguration of Space Launch Complex 2S at Vandenberg Air Force Base. The United States Air Force planned to use Vandenberg for its own classified polar orbit missions, which would require much more payload than the Lifter could provide in a dog-leg trajectory from Cape Canaveral, but this first mission would see the Lifter Intrepid launch the Orbiter Resolution on its second orbital flight. Operating the Lifter at Vandenberg had raised some initial headaches for Air Force engineers--the complexes most suitable for conversion to accommodate the high-thrust RS-IC, SLC-4 and SLC-6, were both simply too difficult to access. Winding roads through the rugged Californian coastal hills meant that the Lifter would have to be raised impractically high off the ground to avoid shearing off its wings. This meant that an entirely new pad would have to be constructed due west of the Vandenberg AFB airfield, adjacent to SLC-2, a Thor-Delta launch pad. The work of building up this new pad delayed the commencement of West Coast Lifter launches until almost five years after the program first took flight, but when the Lifter began operations in California, it hit the ground running.

    Resolution would fly from VAFB twice in 1984. Her first flight, STS-48, would be a single-orbit polar test flight, simply to validate the high cross-range capability for which the lifting body design had been chosen in the first place. While a meteorological observation satellite was co-manifested and was separately injected into a polar orbit by the S-IVC after the Shuttle separated, the biggest question on the minds of American officers (and their Soviet counterparts, glued to their radar sets as they watched Resolution sail overhead) was whether the Orbiter could compensate for California shifting to the left about 1,000 miles. Under the command of CDR Robert Overmyer and Pilot Donald Peterson, Resolution reentered the atmosphere over the Arctic Ocean, screamed through the mesosphere at hypersonic speeds over Alaska and British Columbia, and, with a triumphant sonic boom, soared down the length of the California coastline before coming in for a successful landing at Vandenberg.

    Work on turning Resolution around for her next flight began immediately. Though mostly a USAF Shuttle, on her next flight, STS-52, Resolution would carry a NASA payload--the Spaceborne Imaging Radar (SIR), a large radar array that filled almost the entire volume of the Orbiter’s small payload bay, and took up so much power and payload mass that no other experiments could be flown with it. SIR allowed NASA to generate very high-resolution radar images of every square meter of land on Earth, from the frigid wastes of northern Greenland to the frigid wastes of the Transantarctic Mountains, and all the mountains, deserts, forests, jungles, prairies, cities, and farms in between. The SIR would fly on Resolution three times between 1984 and 1987, revealing new details about Earth’s landforms hidden by dirt and vegetation accumulated over the centuries. While the radar array would uncover new information about the dynamics of volcanos and discover buried temples and sections of China’s Great Wall, the discovery that generated the most speculation was the announcement by NASA geologist Farouk El-Baz that, by analyzing SIR measurements of the Arabian desert, his team had uncovered two dried-out riverbeds that had once flowed across the peninsula, from Medina to the Persian Gulf. In and of themselves, the two riverbeds would have been of interest only to archaeologists searching for relics of the forerunners of Near Eastern civilization, but their location, the fact that they joined the Tigris and Euphrates in the Persian Gulf, which would have been a marshy river valley in the Neolithic, inspired tabloid newspapers to proclaim to the world that NASA had uncovered the Garden of Eden. To El-Baz’s embarrassment, the think tank Answers in Genesis would claim his work as direct evidence of a Young Earth. Though Resolution’s record of enhancing the scientific literacy of the general population was a bit spotty, the data it recovered with the SIR instrument has been of enormous value to geologists, ecologists, and archaeologists studying worlds hidden away by the relentless sands of time.

    The first interplanetary payload launched by Lifter-Centaur was also one of the highest-profile interplanetary missions yet organized by NASA. Since 1968, the Planetary Science Decadal Survey had identified Jupiter as the target of greatest importance, both for understanding the planet itself and its role in the formation of the solar system, and the interest that its magnetosphere and plasma belts held for physicists. NASA therefore began planning for a Jupiter orbital probe even as the Pioneer 10 and 11 spacecraft flew by the king of the planets in 1972 and 1973, and began construction of the probe that would ultimately bear the name “Galileo” even before the Voyager spacecraft launched on their follow-up surveys of the planet. To the chagrin of planetary scientists most concerned with the possibilities of extraterrestrial life, Galileo was too far along in 1979, when Voyagers 1 and 2 sent back evidence of a subsurface ocean on the moon Europa, to be reorganized toward the Galilean moons. Instead, the spacecraft was designed primarily to probe Jupiter itself, dropping a pair of 400-kilogram probes into the depths of the planet’s atmosphere and studying the planet’s magnetosphere and cloud decks. The moons and rings of Jupiter, though important mission objectives, were secondary to the planet itself.

    Galileo launched on January 24, 1982, and arrived at Jupiter over 3 years later, approaching the planet over the course of 1985. Separating from its two atmospheric probes in March, the spacecraft finally entered orbit around Jupiter on August 17, 1985, beginning a two-year primary mission around Jupiter. As part of that mission, Galileo acted as a relay for data from its two atmospheric probes, which plunged into two different bands of cloud, one into the equatorial zone, one into the south temperate belt. Descending into the Jovian atmosphere at almost 50 kilometers per second, the probes endured the hottest and highest-acceleration atmospheric entry of any spacecraft before or since. Over the course of their hour-long lifetimes within the Jovian atmosphere, the probes descended over 150 kilometers, observing vastly different environments at each latitude. The equatorial probe descended through a comparatively cloudless region of the Jovian atmosphere, later termed a “hot spot,” with much higher temperatures and lower humidities than the surrounding clouds. Its temperate sister, however, found somewhat slower winds and lower temperatures, and clouds of water, ammonia, and ammonium hydrosulfide. Surprisingly, both probes found that the ratio of nitrogen isotopes in the Jovian atmosphere, the ratio of 15N to 14N, was about 30% lower than that found on Earth, indicating that the nitrogen ratio on Earth was not, as previously thought, the primordial ratio--something had occurred to change the composition of Earth’s nitrogen.

    For the next two years, Galileo surveyed the Jovian atmosphere and magnetosphere, and performed observations of the outer Galilean moons (Callisto and Ganymede). The spacecraft also observed the rings of Jupiter and discovered a number of new, smaller moons at low orbits around Jupiter. Following the completion of its prime mission, Galileo began an extended mission, the Galileo Europa Mission, scheduled to last from August 17, 1987 to December 31, 1989. During this mission, Galileo spent more time at lower altitudes, studying the lower Jovian radiation belts and performing close flybys of Europa and Io, the two most geologically active moons in the Jovian system. Since Voyagers 1 and 2 brought them to the attention of the scientific community in 1979, the two moons had been a source of excitement for planetary scientists for different reasons. Io’s widespread volcanic activity prompted questions about how such a small body could produce enough heat to drive the observed eruptions and orogenies, while Europa’s apparently cracked icy surface drove speculation about the possibility of a water-ice ocean underneath the crust, possibly a suitable habitat for non-photosynthetic life. Galileo’s close flybys of each moon raised almost as many questions as they answered, revealing that Io had no functional magnetic field despite being both internally molten and having an iron core, while Europa almost certainly had liquid water under its surface (indeed, the “almost” qualifier dropped out when Galileo fortuitously observed plumes of water jetting from Europa’s southern polar region in February of 1989), though the potential of that water for habitability remained heavily debated.

    The smashing success of the Galileo mission, however, was still years off when, in 1981 and 1982, NASA’s planetary science program found itself fighting for its very survival in the face of a Congress whose rallying cry had become “fiscal responsibility.” Though Galileo was too far along by 1981 to cancel (with a launch just months off), NASA’s two other flagship space science missions, the Venus Orbiting Imaging Radar (VOIR) and the American half of the International Solar Polar Mission (ISPM), were not so fortunate. VOIR was intended to follow up on the recently-launched Pioneer Venus Orbiter mission, which had been thrown toward Venus in 1978 by an Atlas-Centaur rocket. VOIR would use a more powerful, more sensitive radar instrument to produce more detailed maps of the Venusian surface, and answer gripping questions about how a planet so similar to Earth in its composition and size could turn out so different by mapping the entire surface. VOIR’s cost, however, exceeded its budget, leading to its cancellation in 1982. Undeterred, NASA’s Solar System Exploration Committee reiterated the importance of the mission in 1983, and secured funding for a somewhat reduced-scale version of the mission, named the Venus Radar Mapper (renamed “Magellan” in 1985). To control costs, Magellan would be built from leftover parts designed for the Voyager and Galileo programs, and would launch on a Lifter-Centaur in 1988.

    The American half of ISPM, unlike its inner-solar-system counterpart, would not be resurrected. The Reagan Administration’s FY 1982 budget called for almost a half-billion dollars less for NASA than had been requested, and NASA was forced to perform triage on its own programs. The initial mission plan had called for launches of both the American and European ISPM probes on the same Space Lifter mission in 1983. In 1980, the House Appropriations HUD and Independent Agencies Subcommittee, under the leadership of Representative Edward Boland (D-Mass.) voted to cancel the mission, but the State Department, White House, and other members of Congress reacted strongly enough to reinstate the mission for a 1985 launch. In 1981, however, the White House was under new management, and this time the budget cuts stuck. Though the American ISPM probe had some instruments and capabilities (including a despun instrument array) that the European probe could not match, it was a lower-priority mission for NASA than VOIR, Galileo, or the upcoming Space Telescope.

    They could scrape together enough funding to satisfy the Europeans by launching their probe, but not enough to finish the American counterpart. The whole mission, however, was more than the sum of its probes--one ESA official commented that the loss of scientific value was “considerably more than 50%.” The European Space Agency heavily protested the cancellation of the American probe, noting that ISPM had been chosen above many all-European missions in the interest of transatlantic cooperation. The Agency even offered to build a copy of its probe and sell it to NASA for $40 million (though in truth, the loss of tax revenue and the impact of inflation and increased support costs would drive the real cost to $75 million), while the American contractor, TRW, proposed for its part a simplified probe that excised the despun instrument platform for a cost reduction to $120 million. Budgetary constraints carried the day, unfortunately, and on September 11, 1981, the National Academy of Sciences recommended the cancellation of the American half of the ISPM. The apparent unreliability of the Americans for long-term projects left a sour taste in the mouths of ESA’s leadership, one that took years of close cooperation on Spacelab to wash out, but which never entirely went away.

    Though hopes that Venus was a lush, earthlike world were dashed on the rocks of infrared astronomy in the 1960s, the planet remained an object of great interest to planetary scientists. Indeed, as the scientific understanding of Earth’s climate and geological history evolved with the discovery of plate tectonics and the first inklings of the modern consensus on climate change, Venus grew even more interesting. How could a world so similar to Earth, just a hair smaller, have turned out so differently? Why is its rotation retrograde? Why is its atmosphere so thick and dry? Why does it lack a magnetic field?

    These questions and others motivated the Solar System Exploration Committee at NASA to first recommend the Venus Orbiting Imaging Radar as a top priority in the 1970s, and to fight for it in at least a reduced form after its cancellation. The fruit of their labors was the Magellan probe, a spacecraft constructed mostly from spare parts from the Galileo and Voyager programs. A follow-on to the successful Pioneer Venus Orbiter and Multiprobe mission of 1978, Magellan was to map the surface of Venus in unprecedented detail using its synthetic-aperture radar, improving on the earlier probe’s multi-kilometer resolution by discerning surface features as small as 100 meters across.

    On the Magellan program’s shoulders rested not just the livelihoods of Venus researchers, but the fate of an entire planetary science program--Mariner Mark II. Recommended by the Solar System Exploration Committee in 1983, Mariner Mark II was designed to prevent repetition of the cost overruns of the Voyager and Venus Orbiting Imaging Radar programs by standardizing future space probes around common hardware and software solutions, rather than special, single-use components. Though economies of scale were difficult to apply to space probes, which by their nature were produced only in limited numbers, such standardization could at least reduce the development costs of new spacecraft, enabling NASA’s planetary science budget to stretch further. Magellan, though not formally a part of the program, was in many respects a proof-of-concept--its cost was controlled by reusing Galileo and Voyager spare parts. In that respect, it was a success--at the time of launch, the spacecraft had only cost $300 million to develop, which, while a significant overrun from the initially-planned $260 million, was still far below the estimated $500 million cost of Magellan’s predecessor, VOIR. The success of the Magellan program in avoiding cost overruns strengthened the cases for the first two planned Mariner Mark II spacecraft--the Saturn Orbiter/Titan Probe and the Comet Rendezvous/Asteroid Flyby, both planned for the 1990s.

    Even as the Lifter system won for itself new laurels, many officers of the United States Air Force came to see value in an independent, redundant space access system in the early 1980s, as the Space Transportation System took over a growing share of the American and global commercial satellite market. As the US transitioned from a liquid-fuel ICBM fleet to an increasingly solid-fueled one, and as the commercial satellite market shifted to the Space Transportation System, the costs of maintaining the Atlas, Titan, Thor, and other rocket families mounted for an ever-shrinking return. Though the Reagan Administration never realized its goal of privatizing the entire American space launch sector, as the manned Orbiter flights remained under the administration of NASA’s Manned Spacecraft Center, the process of developing new launch vehicles and contracting for launches was taken out of NASA’s control and left between the satellite operator and the company that actually built the rockets--just as STC took over operations of the Space Lifter, Convair, Martin-Marietta, and McDonnell-Douglas handled operations of their respective expendable rockets. With the birth of satellite television in the 1970s, went the thinking, would come a new era of commercial competition to develop cost-effective ways to service this new economic sector. Such competition rendered government-developed launch vehicles superfluous or even counterproductive--who would compete with a government-subsidized rocket, after all?

    A casualty of this faith in the Invisible Hand, unfortunately, was the so-called “Shuttle Phase II.” Since the compromise that had birthed the Space Lifter architecture in 1972, NASA’s engineers had been predicting that a fully-reusable second stage would supplant the S-IVC and Glider by the 1990s, at the latest, and had pursued design studies and low-level technology development programs to this end. NASA’s Marshall Space Flight Center, in particular, had experimented with small staged-combustion-cycle rocket engines of the type thought necessary to deliver the performance a reusable upper stage would need, while Ames Research Center and Lewis Research Center studied advanced materials and aerodynamic shapes for hypersonic flight. These efforts received a sudden shot in the arm in the late 1970s, when the Carter Administration’s interest in renewable energy led NASA to study multi-thousand-tonne orbital solar power platforms, whose enormous bulk would be uneconomical to fly on the Lifter stack even in the most optimistic scenarios. Orbital solar power platforms would require revolutionary new launch vehicle designs, capable of placing hundreds of tonnes in orbit while reusing the entire vehicle.

    Though collectively referred to as “Shuttle Phase II” or simply “Shuttle II,” the proposals generated in the late 1970s differed greatly in the exact approach to full reusability and high payload. Some of the proposals, particularly those put forward by Boeing, proposed a system of two winged stages that returned to runways, essentially an expansion of the then-in-development Lifter stack. Chrysler, for its part, dusted off its SERV proposal from the early 1970s for a single-stage-to-orbit capsule, while Johnson Space Center proposed an enormous, 700-tonne-payload rocket whose stages would splash down in the ocean for recovery. Rockwell’s proposal was arguably the most exotic--a ramjet-powered spaceplane that would fly from a runway to orbit with a 100-tonne payload, 16 times per day. All of these plans seemed to come to nought when the Reagan administration came to power and limited development funding for both the advanced launch vehicles and the orbital solar power platforms that justified them.

    Though most of the “Shuttle II” ideas were shelved because their multi-hundred-tonne payload capacities had no discernable market in the 1980s, one proposal--from Martin Marietta, for a two-stage, pop-up vehicle whose first stage would land in an artificial freshwater pond and whose second stage would circumnavigate the Earth before joining it--proved far more adaptable. Martin Marietta, the prime contractor for the Titan II and Titan III launch vehicles, had not managed to gain a stake in the Space Transportation System. As the Shuttle came together and proved, in its first test flights, capable of handling any given commercial, government, or military payload in cislunar space, the company’s executives could see the writing on the wall--unless Martin Marietta came up with an answer to the Shuttle, one that could be sold to NASA at a considerably lower per-launch cost than Titan III, the company faced the total extinction of its space launch division. As such, unlike the other companies to submit design studies for Shuttle II, Martin Marietta continued to develop its proposal on its own dime.

    Though the Space Transportation System had only flown a dozen orbital missions when the Reagan administration began its shake-up of American launch contracting, it had almost flawlessly demonstrated the ability to send satellites to geostationary orbit, to launch multiple satellites at once, to approach and observe an uncooperative satellite at close range (demonstrated on the third Orbiter mission), and to launch satellites into a polar orbit from both the West Coast and the East. Experience servicing the RS-IC on the ground indicated that the F-1B engines and aluminum airframe were holding up almost as well as expected--the engines in particular, having been in service in some form for 20 years, had well-understood tolerances, and the flight regime was not more demanding than that for which they had originally been designed. Though time between flights was still greater than NASA had intended, and consequently the cost per-flight was somewhat greater, the STS looked to be well on its way to fulfilling its promise of reduced cost per-kilogram-to-LEO. Of the vast American arsenal of expendable rockets, only Scout seemed safe from obsolescence (its payloads were too small for STS to launch economically, except as a secondary payload).

    There was, however, a marginal case where the economics of the STS seemed questionable. The three-ton-to-LEO payload class, served by the Titan IIIB, was also small enough that a dedicated Lifter launch was uneconomical. However, its payloads tended to be sensitive Department of Defense payloads--generally KH-8 reconnaissance satellites and signals intelligence payloads. The United States Air Force was skeptical enough about sharing an architecture with the civilian space program; putting such sensitive payloads together with civil payloads was simply unfeasible. No one wanted to have to give civilian payload technicians the high-level clearance needed to get within feet of USAF payloads.

    It would be this market that Martin Marietta tackled with its Reusable Launch Vehicle program, which envisioned a massively scaled-down version of the company’s Shuttle II proposal. Where Shuttle II aimed to put three hundred tonnes in LEO per launch, Martin Marietta’s RLV aimed for the three-to-ten-tonne market. The RLV program operated for approximately 18 months (a clear delineation between it and its successor, CRLV, is difficult to make), during which Martin Marietta changed the recovery method from “freshwater splashdown” to “vertical landing,” as further research concluded that recovery and capital costs would both be considerably lower if the booster’s stages could land on with legs on a concrete pad (a recovery method considerably easier for the small RLV than the gargantuan Shuttle II). Martin Marietta also pioneered the use of “slush hydrogen” propellant, which offered greater performance for a given volume of propellant, though experiments with composite propellant tanks proved, for the moment, unsuccessful. The development of the RLV project would prove extremely useful for Martin Marietta, as other groups were coming to similar conclusions about the capabilities of the Space Transportation System..

    In 1983, the United States Air Force, with the blessing of Air Force Undersecretary Pete Aldridge, began a program called “Complementary Reusable Launch Vehicle,” to develop a miniaturized STS optimized for those payloads smaller than 10 tonnes. As its name suggested, it would fly those payloads for which the Space Lifter would be oversized, and having two disimilar reusable launchers would offer a backup to pick up the slack in the event of a fleet-wide stand-down of either system. As Aldridge would say in an interview with Aviation Week & Space Technology in 1988, following his retirement from the USAF, “we never doubted that the Space Transportation System would achieve airliner-like operations. It’s just that we remembered that even airliners have to stand down sometimes.” Secretary of Defense Caspar Weinberger evidently agreed with that sentiment, as in 1984, he approved a space launch strategy that included the development of a CRLV with a payload of 20,000 pounds. Though somewhat smaller than the largest of the Department of Defense’s payloads, the NRO’s new Low Earth Orbit reconnaissance birds, 20,000 lbs was enough to cover the majority of the Department’s geostationary orbit payloads.

    The two companies with the biggest stakes in CRLV were Martin Marietta and McDonnell Douglas, the latter of which, like Martin, was watching its stake in the expendable launch vehicle market evaporate. Martin Marietta manufactured the Titan III series of rockets. Derived from the Titan II ICBM, these rockets had been the backbone of the Air Force’s launcher fleet for almost twenty years. McDonnell Douglas, having purchased the Atlas and Centaur production lines from Convair, was also watching most of that investment pass into obsolescence. Though the Centaur would survive as an upper stage for a handful of STS missions beyond Earth orbit, Atlas was on its way out. Both Martin Marietta and McDonnell Douglas understood that, if they wanted to retain any share in the launch market, they had to act now.

    McDonnell Douglas’s proposal was a fairly straightforward miniaturization of the STS. Pairing the Centaur Plus developed for STS with a new kerosene-powered flyback first stage, their proposal offered a fairly low development cost (not that the Reagan-era Defense Department wanted for money) and a high degree of confidence by using existing hardware. The greatest innovation in this system, relative to the STS, was in the automated piloting equipment for the first stage--it could return to its launch site without a human pilot.

    Under the leadership of Norm Augustine, Vice President of Technical Operations (and soon to be CEO), Martin Marietta proposed a scaled-up version of its RLV project, using its in-house Slush Hydrogen propellant systems, and new high-thrust hydrogen-burning rocket engines. These engines, derived from studies done by Pratt & Whitney and, earlier, Marshall Space Flight Center, would use the staged-combustion cycle, and pick up where the HG-3 project left off. Though more expensive to develop, Martin’s design promised a much lower per-flight cost than McDonnell Douglas’s. As the Strategic Defense Initiative began to take shape, it became clear to the USAF’s leadership that the Department of Defense might soon need a considerably cheaper method of launching payloads to orbit than even the STS could provide. Martin Marietta’s proposal promised more of what they really wanted, and so the company received a Phase A contract in February of 1985 that included a provision for a proof-of-concept vehicle--a vertical-landing demonstrator rocket, dubbed the “Terminal Descent Demonstrator.”

    While Space Lifter’s example drove reorganizations and shakeups in the American launch market, Space Shuttle was offering new and exciting options for space utilization. In particular, the Spacelab program also gave NASA engineers an impetus to test an idea that had been kicked around the aerospace industry for over twenty years. Almost as long as there had been orbital rockets, engineers had looked at the upper stages, which entered orbit with the payload, with a nagging sense of guilt that such large pressure vessels were hauled all the way to orbit but then allowed to drop back into the atmosphere to get torn up by hypersonic air resistance. There had therefore been no shortage of suggestions of how to utilize the orbital stages of the rockets--melting them down to recover their aluminum for orbital construction, using them as propellant for electric thrusters and mass drivers, and, of course, returning them to Earth for reuse. But none of these ideas was as enduring as the Wet Workshop idea, which called for the conversion of the stage’s propellant tank into habitable volume. In the Wet Workshop idea, the stage was to vent its residual propellants out into space while a manned spacecraft docked with it, after which a crew would open a hatch in the upper end of the stage to reconfigure it as living space. The idea had a certain romantic appeal--upper stages tended to be enormous compared to the payloads they lifted, after all. Such a Wet Workshop could provide expanded living and working space for a Spacelab crew, allowing the station to gradually expand into the modular space station NASA had always wanted.

    The first serious analysis of the Wet Workshop concept came in 1958, when Dr. Krafft Ehricke, working for Convair, noticed that the SM-65 Atlas ICBM could actually boost its core sustainer stage into orbit. He proposed to fit the core stage with a nuclear reactor and a docking port, so that the oxygen tank could be used as living quarters. The Atlas space station would tumble end-over-end to generate artificial gravity, and be serviced at least a dozen times a year by glider flights from Earth. Though the United States did not develop the concept, the basic themes would be revived by Wernher von Braun at Marshall Space Flight Center, who proposed to use the S-II stage of a Saturn V as a massive, 100-tonne space station. MSFC also proposed to use the smaller S-IVB stage on the Saturn IB as a Wet Workshop, and proposed to use the upper stage of a Saturn V in the same manner as a habitat for missions to Venus.

    It did not take long for the S-IVC, which was even larger than the S-IVB, to attract the same attention from space station planners. Indeed, since it was much longer than the S-IVB, the stretched stage suggested possibilities for the same tumbling artificial gravity experiments that Ehricke had proposed in 1958, enabling long-term studies of the impacts of lunar and Martian gravity on living organisms. The low cost of the S-IVC (as over a dozen were manufactured each year) and the high launch rate of the Space Lifter hinted at a future where dozens of S-IVCs could be linked up to form octagons and larger shapes, massive wheel-shaped space stations hurtling around the Earth and between the planets. And all it would take to prove the concept would be a single mission, an Orbiter flight that would rendezvous with its own co-orbiting upper stage so the crew could verify the processes needed to outfit the space station. The temptation to test the low-cost promises of the Wet Workshop idea proved too great for even the budget-conscious Reagan Administration to turn down. NASA’s FY 1985 budget included funds for a Wet Workshop demonstration mission, to use a modified S-IVC (fitted with mesh floors and wall brackets for equipment attachment, and a docking collar) and a Docking Module made with surplus parts from the Spacelab project and the Apollo-Soyuz Test Project.

    The Wet Workshop would not be the final evolution of the S-IV stage family, however. During the development of the Space Lifter and Orbiter, concerns about Orbiter weight gain led Marshall Space Flight Center to dust off the concept of a two-engine upper stage. In addition to its original purpose of increasing redundancy and guarding against the possibility of an engine-out, the second J-2 would increase the Low Earth Orbit payload of the Space Lifter stack by some seven to eight tons, reducing pressures on the Orbiter’s engineers to cut weight and increasing the amount of payload that any Low Earth Orbit mission could carry. By 1977, the Spacelab program was well underway, and Marshall Space Flight Center also desired the additional payload for missions to the European space station. Again, however, the proposal (dubbed “DEUS,” for Dual Engine Upper Stage) fell on deaf ears. NASA Headquarters pointed to the budget projections for the rest of the 1970s, and at the relative dearth of payloads that would actually require the extra payload (as most Lifter missions were aimed at Geostationary Transfer Orbit, and carried satellites already undersized for the Lifter stack). It was not until 1984 that DEUS rose from the dead and took its place as a fully-funded Space Transportation System component. The Strategic Defense Initiative begun by President Reagan envisioned fleets of high-mass, low-orbiting defensive installations that could deploy high-powered lasers to intercept Soviet ballistic missiles. As time went on, the program’s interests diversified into tactical support (in the form of Dr. Jerry Pournelle’s “Project Thor” concept) and kinetic interception of enemy missiles, but a single theme kept recurring: the need for high-mass payloads in low orbits. By the late 1980s, NASA was moving into plans for a larger follow-on to Spacelab, a permanently-manned outpost in a Low Earth Orbit, and so, for once, the interests of the Department of Defense and those of NASA were fully congruent. The FY1984 budget included an allocation of $100 million for the development and testing of a Dual Engine Upper Stage, for a first flight in 1988.

    This more capable and more resilient upper stage wasn’t the only improvement to the Space Transportation System. As the Space Shuttle had built up a flight history, it had become apparent that missions involving external payload deployments were not the limits of the Shuttle system’s applications. The Shuttle had also increasingly attracted attention as a manned science platform and as a cargo transport to Spacelab. For both uses, the Shuttle’s large cargo bay represented a weakness, not a benefit, as the result was a smaller pressurized cockpit. Although several times the size of the Apollo capsule, the Space Shuttle was poorly equipped to handle a crew of more than four or any extended duration, even though it was technically capable of supporting such a crew. Moreover, when supporting a larger crew, the volume available for experiment storage in the cabin was sharply limited.

    By adding a pressurized module mounted inside the bay on such science or cargo-focused missions, the Shuttle would be able to make better use of both its existing or future expanded payload capacities. NASA successfully lobbied for funding for the construction of a Multi-Purpose Expansion Module, and a specification was issued in 1983 for construction of two flight-qualified units. Though bids were received from most aerospace firms, there was an expectation within STC’s management that the contract would fall naturally to one of the original STS contractors. The award of the contract to Grumman Aerospace Corporation of Bethpage, New York came as a surprise. As with their proposals for elements of the Space Transportation System, Grumman’s bid was ranked well on cost and technical details, drawing on their Sortie Can studies earlier in the decade. Grumman’s submission was noted for its lightweight structural design and their analysis of how to optimize the design for operational flexibility. Grumman’s STS bids had been hampered by worries over the company’s management and finances. However, many of these had been resolved in the meantime by events such as the delivery of the F14 Tomcat fighter and NASA was less worried on a project that ultimately consisted of little more than delivering an empty metal tube with mounting brackets and wiring trunks which NASA itself would then operate and improve. Demonstrating that NASA was open to encouraging cooperation and that STC would not be allowed to form an effective government monopoly was a side benefit.

    Even without the improvements which were planned, the Space Lifter and Space Shuttle forged on with their operations. With Spacelab missions added to the existing manifest of free-flight science and satellite deployment missions, the Space Shuttle flew six times in 1983, during which the Shuttle was used to retrieve the Long Duration Exposed Facility. Adding these to the growing manifest of commercial, scientific, and military satellites riding Space Lifter, the Space Transportation System was boosted above an average of one flight per month. The flight rate only continued to improve in 1984, with eight Shuttle flights and twice as many total Lifter launches, including the program’s fiftieth mission. While improvements to the system and weather shook up the schedule, the Space Transportation pushed ahead in checking off milestones and continued to drive up its flight rate.
     
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    Chapter 9: Staging
  • "Clearly our first task is to use the material wealth of space to solve the urgent problems we now face on Earth."

    Chapter 9: Staging

    The five F-1B engines of the RS-IC, between them, burned over 13 tonnes of propellant per second. As the Space Lifter ascended, its mass dropped, and the crew of the Lifter and the Orbiter were pressed back into their seats by a growing acceleration. At T+120 seconds, the center F-1B was shut-down to limit total acceleration to 4 G, while the four outboard engines gradually throttled back. This was the toughest part of the ascent on the crew, though compared to Commander Young’s Gemini flights, it was downright forgiving.

    At last, the flight computers, through a combination of accelerometer input, ground-based tracking, measuring mission elapsed time, and readings of the actual level of propellant in the tanks, determined that the Lifter’s boost phase had reached its end. The four remaining F-1Bs shut down, and for a moment, the Lifter, Orbiter, and S-IVC coasted over the Bahamas unpowered. Then the pyro bolts on the S-IVC’s rear adapter fired, separating the upper stage from the blunt, graphite-covered nose of the Lifter and exposing the J-2S-2 engine to the near-vacuum of Earth’s mesosphere.

    Commander Young and Pilot Crippen could watch the S-IVC drift away before the engine lit, but only for a moment. Peroxide thrusters on the nose and tail of the Lifter put it into its pitch-over maneuver--first, to protect the fragile windshield and upper surfaces of the Lifter from the high-speed steam and hydrogen blasting out of the J-2S-2, and second, to prepare for the retro burn that would return Constitution to Kennedy Space Center. The nose pitched upward, slowly, and the S-IVC disappeared from view. After a time period that felt much longer than it truly was, Young and Crippen felt a gentle acceleration from the cooling gasses of the J-2S-2 plume bouncing off their heat shield--just 1.2 meters per second per second, and tapering off quickly--and happily reported to the ground, “Houston, be advised, Lifter crew confirms S-IVC ignition.”

    “Roger, Constitution, we copy. Orbiter crew and telemetry confirm.”

    As the S-IVC sped away from the Lifter, Young noted not for the first time that the acceleration felt familiar. “Almost feels like the Moon,” he observed over the comm loop. “I don’t know about the Moon, but if you’re done catching our wake, we’ll see you on the other side of the sky,” Fred Haise replied from Endeavour, now tinged with the crackle of relay instead of the crispness of the stack’s internal communications links. The gentle acceleration, indeed close to lunar gravity experienced by NASA’s last flying moonwalker--but not by the STS-1 Orbiter Commander--had been brief, though. The S-IVC was already further away from the Lifter, and no longer pointing dead-center toward the Lifter’s flat underbelly. The force of the rocket exhaust on the Lifter dropped away as the booster slowly, gracefully continued its pitch. The blue-white arc of Earth was beginning to crawl back into view in the Lifter’s windshield, as the immense craft’s engines oriented themselves forward, along the line of flight.

    In the Orbiter, Haise and Truly performed the immediate post-staging checks. The J-2S-2 struggled to push the stretched upper stage and its 40-tonne payload along, managing only ⅓ G at first, but steadily increasing as propellant burned off. It didn’t need to subject its crew to bone-crushing forces at this point, though--the Orbiter and its stage were still coasting upward on the momentum imparted by the RS-IC, and the J-2S-2 worked to impart the horizontal velocity needed to stay in space, rather than just get there. Without the Lifter’s power, the flight could not have happened--but without the S-IVC’s high-energy engine, it wouldn’t have had much point. Slowly, steadily, the Orbiter gained speed, pushing out over the Atlantic, the apoapsis of its orbit stretching further and further off ahead.


    The middle of the decade brought a slow maturation in the Space Transportation System. The system’s flight rate continued to increase, with the 50th launch of a Space Lifter carrying the Space Shuttle Destiny to space on her maiden flight in May, 1984. The flight was the last for several months for the RS-IC-602 Constitution, which had reached its 18th launch, and thus was due for its SLIP-II inspection to check how the booster’s structures and systems had aged since the SLIP-I inspection four years and a dozen flights before. The expectations were for a clean bill of health, like the one her sister Independence had just recieved on her own SLIP-II inspection the year before. The largest complications in the inspection had been the replacement of several of the booster’s avionics and cockpit controls, bringing the 1970s-vintage computers closer to modern standards. The cost of the STS continued to trend down, as STC and NASA were able to spread costs for commercial, USAF, and NASA missions across more flights, and as cost reductions and increased automation were implemented in the production of the expendable fairings and upper stages for Space Lifter missions. Given that a Space Lifter launch was already cheaper not just per-kilogram but per-flight than a traditional expendable Titan or similar rocket, it was little surprise that the vehicle had been embraced by institutional and commercial payload planners, with many customers beginning to order satellite busses which could barely be lofted by expendable launchers at all. Beyond cost reduction, taking advantage of the Space Lifter’s immense payload capacity gave engineers the chance to add more margin to satellite payloads for only a marginal increase in cost. In some cases, adding redundant systems and more propellant capacity reduced insurance premiums, reducing the overall cost of communications satellites even as they grew in size and capability. This benefit is perhaps best demonstrated in the recovery of the Geostar 1 satellite in 1986.

    The brainchild of space colonization visionary and physics professor Gerard K. O’Neill, Geostar was an early forerunner to the satellite telephone craze of the early 1990s. Combining position triangulation with satellite text messaging, Geostar was conceived as a method of helping airplane pilots avoid collisions. O’Neill, himself an avid pilot, had been horrified by the 1978 collision of Pacific Southwest Airlines Flight 182 with a Cessna 172 light aircraft, which killed 144 people. Blaming inadequate aircraft navigational and positioning systems, O’Neill resolved to address the problem himself, and generate income for his Space Studies Institute in the process. After receiving patents for the geostationary communications/navigation satellite system, he founded Geostar Incorporated in 1983. Following successful ground tests of the system, which would relay signals from three GEO satellites covering the entire United States through a ground-based supercomputer that would compute latitude and longitude coordinates and relay them back to the receiver, Geostar purchased a launch of the Space Lifter in 1986, to inject all three satellites into their staggered, 30-degree-apart positions in geostationary orbit.

    The Geostar design was not perfect, and issues with the satellites’ relatively complex electronics cropped up within hours of orbit circularization. Though Geostar 2 and 3 operated fairly nominally after a few hours of troubleshooting, Geostar 1 continued to malfunction. Far beyond the Low Earth Orbit that could enable servicing by the Space Shuttle, Geostar had to rely on software fixes implemented on Earth. After a time, Geostar’s engineers succeeded in contacting Geostar 1 by first relaying signals through the Geostar 2 satellite, thirty degrees behind Geostar 1. Using the Geostar satellites’ redundant omnidirectional communications system (a system designed primarily for emergency telemetry transmission), Geostar’s engineers discovered that the satellite had lost attitude control during its apogee-raise maneuver. Though it was in the correct orbit, it was unable to point either toward the Earth for high-gain communications or toward the sun for efficient battery charging. Luckily, the satellite had larger-than-usual batteries (added in order to retain full operability during the eclipse phases of its orbit), and the engineers had many hours to reprogram the satellite and reset its attitude control system before they wore down. After a frightening first day in geostationary orbit, Geostar 1 joined its fully-operational sisters and enabled the company to perform the final tests of the Geostar satellite communications system before pre-ordered receivers could begin shipping out.

    The recovery of Geostar 1 enabled Geostar to gain a foothold in the growing field of personal satellite communications and in satellite navigation. Though the system was not so all-encompassing as the Global Positioning System, which was entering commercial use at the same time, it made up for that with the added utility of direct, receiver-to-receiver satellite communication. Though O’Neill had designed the system for aviation, it found greater use in the land-based shipping industry, connecting truckers to dispatchers more efficiently. Businessmen also found immense use for the Geostar system, using it to stay connected to their offices even when on vacation (the image of the neglectful father, so engrossed in his work that he “taps” out messages to his office even on family vacations, became ingrained in American culture through family movies in the 1990s). Geostar also found use as a disaster-relief tool, keeping emergency workers in close communication with their dispatch centers following the Northridge and Great Hanshin Earthquakes in 1994 and 1995, when power failures disrupted both landline telephones and cellular communications. Though not the most versatile satellite-based communications system (the long light lag and power requirements for communication between Earth and geostationary orbit making use for voice communications impractical), Geostar retained a large stake in the market. With a text only system and relatively infrequent information transfers between receivers and the orbiting satellites, Geostar could offer a longer battery life for its receivers, which made it particularly useful as an emergency communication system that needed to work any time, for a long time. However, the limitations of Geostar’s geostationary platforms pointed the way for advocates for lower-orbiting satellite telephone constellations of the 1990s.

    More significant in the minds of space colonization advocates, however, is the relationship between Geostar and O’Neill’s Space Studies Institute. Two years after he founded the SSI in 1977, O’Neill realized that modest donations would never suffice to develop the capital needed for a real expansion onto the High Frontier. He declared that all income from his future patents would go to SSI, and made the SSI the majority (though non-voting) shareholder in Geostar. The Space Studies Institute, created to research ways to industrialize space, ranging from lunar mass drivers and mining plants to space solar power stations, became the only space advocacy organization to have a large, consistent source of funding--an advantage that would make SSI by far the most influential of the organizations that emerged in the aftermath of the Apollo Program to promote the vision of the human conquest of space.

    Such workaday successes heralded the success of the Space Transportation System in many of the goals for which it had originally been approved, even as the regular and repeated flights meant that the latest Space Lifter mission received little more than an occasional mention on nightly news or a few paragraphs in the newspaper. Crowds attending flights of regular Space Lifter launches ebbed, and even Space Shuttle missions began to see dropoffs in attention. The crowds heralded a transition in the way the public and even NASA thought of the STS: it was no longer exciting to see a massive first stage returning to land only minutes after carrying an upper stage and payload to space. The potential lay instead in the payloads it could carry, and the missions it could enable. Spacelab, the Galileo and Ulysses space probes, and the European LDEF were just a few examples of these, but one of the most publicly heralded was that of space-based telescopes, both those looking outward, and those with their gaze turned earthwards.

    Plans for a large, multispectrum orbital observatory had originally begun in 1965, but in 1970, NASA divided work on the project into two overall camps: a Large Space Telescope Task Group, tasked with determining the engineering requirements of such a device, and a Scientific Advisory Committee to determine the scientific requirements. Though both Marshall and Goddard Space Flight Centers had conducted Phase A studies of the telescope, Marshall’s work on what would become Space Lifter, along with Skylab and the last few Apollo missions, meant that Goddard took on more work as time went on. Both the LST Task Group and SAC transferred to Goddard permanently in 1972.

    The Large Space Telescope (eventually shortened to just “Space Telescope,” when certain managers suggested that it might be greatly outclassed in the coming decades,) had a hard fight in Congress. As with the Lifter and Orbiter, NASA attempted to deflect congressional hostility by underreporting the estimated cost of the Telescope, giving a cost target far below that calculated by Goddard in 1973. Hostility from astronomers from West Coast universities (who had been spoiled by their high, dry mountains and deserts and the large observatories placed at their peaks, and viewed the Space Telescope as unnecessary and unfeasible) did not help the telescope’s case. It took aggressive lobbying of the National Academy of Sciences to get the Telescope recommended as a top-priority project. President Ford’s federal budget cuts and renewed attacks by William Proxmire in 1975 again delayed the start of the program to FY 1978.

    The final design of the telescope hinged on a major decision about the diameter of its mirror. At the start of the program, a general consensus emerged that one of the major scientific goals of the project--measuring the Hubble Constant to within 10% certainty--required a mirror at least 120 inches (3 meters) across. The facilities to build such a mirror did not exist in 1968, and so the program’s budget would need to account for the facilities that would manufacture it. While this initially seemed an insurmountable hurdle for the program, it was also an opportunity--if one needs to build new facilities anyway, why stop at 120 inches?

    Such was the reasoning of the National Reconnaissance Office, whose unmanned reconnaissance satellite technology overlapped, in many respects, with that required for orbital telescopes. As plans solidified in the 1970s for Department of Defense Lifter flights, the NRO increasingly took into account the unmatched lifting capacity and payload fairing size of the Space Lifter stack. While their then-current Titan IIID topped out at 120 inches across, with a 12-tonne payload, Lifter would loft over 40 tonnes under a 260-inch fairing. Though they had just placed the KH-9 series of reconnaissance satellites into service in 1971, the NRO was already planning the next generation. The planned KH-11 series was to demonstrate the revolutionary new technology of solid-state electro-optical imaging. By removing the need to drop film canisters from orbit, electro-optical imaging promised cheaper, faster recovery of intelligence and longer satellite lifetimes.

    KH-11 was rapidly replanned as an interim system, a technology demonstrator for electro-optical imaging using many KH-9 components. The true focus of NRO’s planning in the 1970s was the KH-12 project. Building on experience with the KH-11 in the late 1970s, KH-12 (code-named LUCID) would combine electro-optical imaging with an unprecedentedly large mirror--168 inches, to be ground in a new facility jointly operated by Kodak and Itek Corporation, which had previously built cameras for the CORONA spy satellites and for the Apollo Program.

    The existence of this facility and its capabilities were disclosed to planners at NASA in 1977, and plans for the Space Telescope were redrawn to include a mirror up to 180 inches across. The program found a surprising backer in President Carter, who, according to declassified documents, considered it a way to demonstrate to the Soviet Union an American capability to monitor compliance with the Strategic Arms Limitation Treaties without having to officially disclose the LUCID platform’s capabilities. With the enthusiastic backing of the new President easing the objections of the Office of Management and Budget over the program’s expanded scope, NASA officially began the Space Telescope program in FY1978, though for cost reason they were ultimately forced to accept the same 168-inch mirror size as the KH-12.

    The development process for both the Space Telescope and its classified cousins was long and troubled by frequent budget overruns. Even had the telescopes been ground-based, they would have been the world’s third-largest. Launching an optical apparatus this large, this sensitive, and this complex was a massive undertaking whose cost repeatedly overran Goddard’s estimates, while millions vanished into NRO’s black budget. Coordination with the astronomers who would eventually use the telescope also posed challenges--astrophysicists from West Coast universities were, again, slow to warm to the project, and regarded the increase in angular resolution as unnecessary for the resolution of astrophysical questions. University astronomers in general wanted to ensure that scientific control of the project was handed over to a non-NASA institution, as Goddard was expected to preferentially assign viewing priority to its own in-house astronomers. Finally, ESRO, in exchange for covering the cost of the Space Telescope’s solar arrays, received 15% of the telescope’s viewing time, to the chagrin of American astronomers.

    Among other causes of the Telescope’s long development time was the requirement that it be serviceable by the Space Shuttle Orbiter. NASA had no intention of dropping a telescope this massive and costly into the Pacific until every last photon could be squeezed into its sensors, and thus required that the telescope be capable of receiving upgrades carried on Lifter-Orbiter flights and installed by astronauts. This meant that the Telescope had to be cooperative during the docking procedures and safe for astronauts to work around (sharp edges in particular had to be removed from any place an astronaut’s glove might work), and that the instruments be modular rather than hard-wired in. Originally intended to launch in late 1985, the telescope’s planned launch date slipped first to 1988 and then to late 1989. In the meantime, the program had acquired a new name. Though some had proposed to name the Telescope after Lyman Spitzer, for his tireless advocacy for the project since 1946, Spitzer himself declined the honor and proposed instead to name it for Edwin Hubble. The alternative had twofold meaning: not only would it would honor the importance of his study of cosmic expansion to modern cosmology, but measurement of the Hubble Constant was one of the main scientific objectives of the program. Thus, in 1985, the program was formally renamed the Hubble Space Telescope

    A major, though unheralded, milestone for the Large Telescope program came in 1985, with a west coast launch of the Space Lifter Intrepid. In an unheralded and highly classified mission, Intrepid carried to a polar orbit the first of the the KH-12 LUCID series of reconnaissance satellites which shared some ancestry and a main mirror diameter with the civilian and scientific Hubble. The deployment of the first LUCID platform was largely trouble free, and subsequent launches were planned for the following years, enabling the replacement of the interim KH-11 CCD prototype satellites with the larger platforms using similar imagers and larger mirrors. Though details of LUCID’s capabilities remain mostly classified to this day, KH-12 was dramatically revealed to be the first American spy satellite with color photograph capability in 1986 when color photographs of a Typhoon-class submarine under construction were leaked to Jane’s Fighting Ships. Though the publication would not print another edition of its famous book until after the end of the Cold War, LUCID photographs would be a minor plot point in the film adaptation of The Hunt for Red October, and writer Tom Clancy is known to have a framed copy of one of the leaked photographs hanging in his study.

    This particular rising tide did not lift all boats. Unfortunately for Martin Marietta, the entire CRLV program came under fire soon after its approval in 1985 as the Space Transportation System’s flight rate accelerated and costs remained under control. Congressional backers of the STS viewed CRLV as a threat to their favored program, and pointed out that two reusable launch vehicles split a market that was being addressed well by one. Over the objections of the administration and of Martin Marietta, Congress directed the USAF to change the program into a Contingency Expendable Launch Vehicle program--a limited purchase of some 30 expendable LVs to be kept in storage against any day when STS might actually have to stand down. With the program’s flight rate reaching new heights and few issues encountered, Congressional leadership was confident that CRLV was an unnecessary redundancy.

    The CELV program very quickly converged on Martin Marietta’s Titan IIIC as the launch vehicle of choice. The heaviest of America’s expendable launch vehicles, Titan III was also considerably easier to store long-term than Atlas-Centaur. Unlike the latter, which needed constant pressurization to retain structural integrity, Titan III could stay in a warehouse for years without degradation. In August of 1985, Martin Marietta received a contract for a block purchase of 30 Titan III rockets, after which point the USAF would purchase no more.

    Martin Marietta’s Phase A contract for the Terminal Descent Demonstrator managed to survive the cancellation of CRLV by the skin of its teeth, through a transfer of the program to the Ballistic Missile Defense Organization, a part of the Strategic Defense Initiative Organization that was, later in 1985, renamed U. S. Army Strategic Defense Command. Though SDIO’s plans, as of 1985, assumed the use of Space Lifter for the heavy anti-missile payloads they had in mind, payloads far too heavy for CRLV as-specified, the Terminal Descent Demonstrator was considered an important proof-of-concept for future autonomous RLVs, and the ballistic-propulsive landing profile proposed by Martin-Marietta scaled up much more easily than the winged aerodynamic systems used by the Lifter. Though the United States Air Force had abandoned CRLV, Martin-Marietta and SDIO intended to soldier on with it as far as they could.

    While the Americans were beginning to take the success of their Space Transportation System for granted, the competing system from the Soviet Union began to slowly come out from behind the iron curtain. Unlike the American Space Lifter, whose RS-IC and S-IVC were simple modifications of 1950s-vintage rocket technology and 1960s-vintage structural design, the Soviet equivalent involved several new technologies, and a radically different approach to the basic questions of reuse and vehicle sizing. Of all the rocket engine cycles proposed to date, staged combustion has been the hardest to master. Most rocket engines burn their propellant in a combustion chamber, and blast the hot gas out as quickly as possible, minimizing heating by simply pushing the fire away from the engine with great haste. In order to supply sufficient power to the engine’s turbopumps, a staged combustion engine must burn a substantial fraction of its propellant internally, and drive a turbine with the combustion products, which are so hot and so corrosive that they are capable of burning common steel and aluminum into ashes. Unsurprisingly, despite having already built and flown staged-combustion-cycle engines, the Soviet Union still struggled to produce the RD-170 family of engines. Though the RD-170’s development began in 1976, it was not until 1985 that the engine was ready for flight. As this engine was almost literally the beating heart of the Groza rocket program, its development paced the entire program’s progress.

    In the absence of a working RD-170, Soviet engineers had to find alternative ways to test the cutting-edge automated landing technology of the Raskat rocket boosters and Uragan spacecraft. While the engineers from the Ministry of Aviation Industry were able to test Uragan in both piloted and unpiloted landing modes by simply developing a gliding airplane, analogous to the American Pathfinder, Raskat’s engineers had to take a slower and more expensive approach to validating their product. These engineers, based at the Yuzhnoye Design Bureau in the Ukrainian SSR, needed to validate the aerodynamics and control systems for Raskat at high velocities, in the supersonic and hypersonic regimes in which the rocket would operate and in which it would have to safely pull itself away from the Groza core stage and begin maneuvering to its landing strip. Though sub-scale models carried on Tu-144s and Mig-25s were useful for gathering data in the design process, testing the actual recovery system would need a real flight to Mach 10 and beyond.

    The Yuzhnoye engineers turned to their previous product, the Tsyklon satellite launcher. Though narrower than Raskat by about 25%, Tsyklon shared its 40-meter length and had a broadly similar thrust:weight ratio to the loaded Raskat/Groza stack. Indeed the effort to automate the Tsyklon launch process through the late 1970s meant that the older boosters’ electronics were still close to top-notch, by Soviet standards, and had a great deal of commonality with the systems designed for Raskat. Until the RD-170 was actually completed, Tsyklon would be the closest possible surrogate.

    Three Tsyklon rockets were fitted with Raskat’s aerodynamic controls and air-breathing propulsion package, and launched from the Baikonur Cosmodrome from 1983 to 1984. The first rocket was lost in flight, as a failed wing deployment caused the vehicle to disintegrate due to aerodynamic stresses, with its scattered remains tumbling into the desert east of Baikonur. The next two were far more successful, demonstrating successful deployment of the wings, hypersonic and supersonic flight, and operation of the jet engines. These test flights were noted by the CIA in the 1984 issue of their “Soviet Military Power” report to Congress. Although correctly identifying the tests as part of the Soviet response to Space Lifter, the report cautioned that they could also have application as a new ICBM/cruise missile hybrid intended to thwart the proposed Strategic Defense Initiative missile shield.

    By mid-1984 it appeared that the RD-170 had finally overcome the worst of its development problems and was on-course for integrated testing with the Raskat booster the following year. However, the delays meant that progress on Uragan had continued to outpace that of its carrier rocket, with two flight models of the spaceplane, designated OK-1.01 and OK-1.02, now fitted out and possessing fully functional power and thermal control systems, as well as a basic life-support capability. Unfortunately, without the Groza rocket they remained mere aircraft, not spaceplanes, as even their 25 metric ton structural weight was too great for Proton, the largest existing Soviet rocket. Consideration was given to using Proton to launch one of the planes on suborbital trajectory, but in the end it was decided that the additional resources needed to modify both Proton and Uragan for the test out-weighed the value of the new data such a mission would generate.

    The first test flight of the Raskat-Groza system came on November 4, 1985, when two Raskat boosters lifted off carrying an inert dummy Groza core stage and an inert dummy upper stage. The system launched on a typical orbital trajectory east from Baikonur, both the Raskat performing flawlessly through their ascent phase. The RD-170’s temperamental nature seemed to have been tamed in repeated static testing on the ground, something on which Glushko had insisted after the disaster of the N1 program. Following separation from the dummy Groza, the two boosters coasted downrange until they reentered the sensible atmosphere southwest of the city of Dzhezkazgan, at which point the range safety officers destroyed the water-filled Groza boilerplate, while the Raskats deployed their wings and opened their jet engine inlets. Falling down into the atmosphere, the Raskats shed their velocity over the Kazakh steppe, before turning around to fly back to Baikonur. Though this flight was not announced to the Soviet public, photographs of a Raskat booster landing at the airfields were published in Pravda the following week, announcing a successful test of a new Soviet space launch system.

    The test was not entirely successful, however. While multiple runways had been provided for the boosters in the plentiful land downrange in Kazakhstan, weather changes near launch had forced the boosters to divert to a different runway than originally programed. The change, made near launch time, had resulted in erroneous updates fed to the flight controllers of the Raskat boosters, locking both onto the same runway. While the boosters’ landing times had been staggered to simplify landing operations, the stages were not capable of taxiing themselves off the runway after landing, and the second Raskat rear-ended the first, mangling both and starting a fire on the runway as released kerosene and LOX spilled off. These pictures, naturally, were not shared with Pravda. The accident, a stain on an otherwise flawless first mission for the system, demonstrated the risks of automatic flight controls and the Groza multiple-booster system, but the other benefit was that production of Raskats was far cheaper, and no lives had been lost in the accident. While engineers went to work resolving the software problems once and for all, another two Raskat contracts were assigned to the Yuzhnoye Bureau, bringing the initial order of ten to an even dozen.

    The second test flight came on April 12, 1986, launching into a thick snowstorm. This flight involved two Raskat boosters carrying a live Groza core stage, with a vacuum-optimized RD-170 engine, and a Blok-D upper stage, together with a small Oko (“Eye”) early warning satellite to a Molniya orbit. This highly elliptical orbit gave far better coverage of the high-latitude USSR than did the geostationary orbit favored by the Americans and Europeans, and gave particularly good coverage of the North Pole, over which American missiles would have to pass in a first-strike on the Soviet Union. This particular Oko was modified with a newly-redesigned optical sensor, following a near-disaster in 1983 when an earlier model had mistaken sunlight reflecting off high-altitude clouds for missile exhaust. The injection was successful, and verified the ability of the Raskat-Groza system to put satellites into high orbit using the old Blok-D upper stage.

    It would be up to the third test flight, on June 6, 1986, to demonstrate both the massive new kerosene-powered Groza upper stage and the Uragan spaceplane. OK-1.02 had been the first spacecraft fitted with engines, maneuvering propellant, and a space-rated heat rejection system, and had been christened Berkut (“Golden Eagle,” particularly one used in falconry) by its crew and the technicians who serviced her. Flying unmanned on her first orbital flight, Berkut was launched by a Raskat-Groza stack in a heavy configuration, with four Raskat boosters around a core stage topped by a large 120-tonne kerosene-fueled upper stage. Berkut completed two orbits around the Earth, opening her payload bay and maintaining steady contact with mission control through the Soviet communication satellite network (a combination of Molniya-orbit and geostationary-orbit satellites). Berkut returned to Baikonur exactly 206 minutes after launch, touching down on the runway dead-center just hours after her boosters had done the same downrange. Berkut’s first flight had shown the world that the Soviet Union had a heavy manned spacecraft to match the American one.
     
    Chapter 10: Apogee
  • "New Heights in Reuse: Space Shuttle and the Competition" (Jul '87 cover, Aviation Week & Space Technology)​


    Chapter 10: Apogee


    Though the RS-IC separated from the S-IVC at only 67 kilometers, its five mighty engines imparted enough momentum to it for it to coast to 110 kilometers, just over the Karman line. As the S-IVC and the Orbiter pulled away, and the mild deceleration induced by the J-2S exhaust fell into the noise, the Lifter continued its slow pitch-over maneuver, its nose tilting up toward the black sky. With a loud BANG, the explosive bolts holding the conical interstage to the nose fired, casting the corrugated aluminum shell into the void, drifting slowly, less than a meter per second, away from the Lifter. Even here, aerodynamic forces tugged at both, gently, unpredictably, but the Lifter’s greater momentum reduced their impact on it--the Interstage started to trail behind and drop back.

    With the sun hidden by the Lifter’s bulbous nose, the crew got to gaze upon a clear, black daytime sky, flooded with stars. On earth, the sun’s glare and the scattering of light through the atmosphere hides half of the constellations from view for a large chunk of the year, but in space, the crew got to take in a view of the winter constellations in July. With nothing but the red-tinted analog indicators on the Lifter’s control board to pollute the light, Young’s and Crippen’s eyes adjusted just fast enough to see Orion pluck an arrow from his quiver to attack Taurus. Then, the bright blue-white of Earth intruded through their windshield again, first the Gulf of Mexico, then the green-brown curve of Florida and the much lighter blue-green of the Bahamas. The storms that had delayed the launch were followed by a high-pressure system that left clear skies across most of the peninsula--though the tail end of the storm system was just visible, north and east of Grand Bahama. The Lifter’s ascent continued, and even as they coasted further east, their field of view widened, parts of Georgia and Cuba and Alabama entering their view. Crippen and Young each kept one eye out and another on their controls--the auxiliary power units were performing nominally, keeping the control surfaces ready for entry, and the peroxide attitude-control thrusters were all functional. With earth over their heads, the stars under their feet, and faint red light at their fingertips, the crew of Constitution coasted past the official edge of space.

    The crew only had so long to focus on the view above them before the fast pace of mission events pulled their attention back into the cockpit. As Young confirmed the vehicle’s alignment in retro attitude, Crippen read off a few screens in front of him, confirming the activation of the control systems for the Student Suborbital Experiment Bay. In the nose, a controller began to feed power to the several small, short-duration experiment packages mounted there. Crippen read off the confirmation that the systems were online, confirmed it with the ground, and moved on to the next item on the checklist. With no further interaction, the controller would run through the rest of the mission, putting the small packages through their paces. They ranged in complexity from high-schoolers’ experiments in microgravity boiling mechanics to university-level experiments in crystal development, brought together by a shared need for a cheap, recoverable launch. Cameras recorded the unique fluid phenomena in this strange regime where viscosity dominated and buoyancy was absent, while geiger counters measured the rate at which cosmic rays penetrated the Lifter’s hull as it climbed. Someday soon, many of these experiments would shift to Orbiter flights or to Spacelab, but, for now, experienced researchers and budding scientists alike took advantage of a system with margin to spare. Endeavour was still climbing to the stars, but STS-8 would produce its first scientific data before the S-IVCs engine even burnt out as Constitution coasted toward the peak of her arc.
    [/I]

    The first launch of Russia’s STS-equivalent sparked fiery new discussions about the next stage of American space exploration. While the STS delivered on many of its promises of flight schedule and cost, the Lifter and Shuttle had been conceptualized as enablers for a broader framework of space exploration and exploitation. While the KH-12 and new commercial satellites like Geostar indicated the ways that Lifter was succeeding, Mir pointed out the weaknesses of NASA’s space exploration program. Though the new Grumman Multi-Purpose Extension Module expanded the size and duration of Shuttle missions to Spacelab and the capacity of the system for non-Spacelab missions, there was still lack of direction for the next stages of NASA’s human exploration program. It fell to politicians and planners to decide how to respond, and if Groza and Uragan’s debut would be the first sparks igniting a new competition in spaceflight.

    The American space program had been designed in the 1960s to demonstrate the superiority of the American political and economic system to that of the Soviet Union. It had succeeded in this goal with the landing of Apollo 11 on the Moon in 1969, only for the Soviet Union to (apparently) retake the initiative in the 1970s with the Salyut program, which demonstrated Soviet skill in actual in-space operations. The 1980s saw the pendulum swing back in the other direction, as repeated American successes on all fronts of space activity, from launch to in-space operations to unmanned planetary exploration, seemingly left the Soviet Union in the dust. The debut of Raskat and Berkut in 1986, though only matching earlier American achievements, hinted that the Soviet Union was preparing a big push to retake its lead. Though American space advocates tended toward a libertarian-capitalist ideology, there had always been an undercurrent of authoritarianism and admiration for authoritarian methods in both the advocate and entrepreneur communities and among the rank-and-file engineers and managers of the industry. As Charles Lindbergh had once praised the German Luftwaffe, so his heirs looked at the apparent priority that space conquest got in the Soviet Union with envious eyes. 1986, consequently, saw a flurry of predictions that the Soviet Union was preparing to deploy everything from a permanent space station to solar power satellites to “a colony on the Moon,” in the words of National Geographic. While in retrospect it boggles the mind that so much was expected in space of a power with so little time left on Earth, it must be remembered that very few intellectuals of the 1970s and 1980s seriously entertained the idea that the Cold War’s end was imminent.

    In any case, by 1986, the Space Lifter had been spun off to the Space Transportation Corporation and both the Shuttle and Spacelab were in regular operation. The production lines for both Shuttle and Lifter were closed, with the Orbiter fleet capped at four, plus a set of “structural spares” and the Pathfinder test airframe, and the Lifter fleet capped at 4, a number deemed suitable for up to 30 flights per year indefinitely. In this comparatively sleepy environment, NASA’s engineers and managers had already begun debating their Next Big Thing. Berkut’s flight only added some more fuel to a fire already kindled at NASA. In 1984, Congress had authorized a National Commission on Space, including such luminaries as Thomas Paine, Chuck Yeager, and Neil Armstrong, whose purpose was to outline the programs NASA needed to take the next great steps in spaceflight. In early 1986, the NCS published its conclusions: in order to sustainably expand human presence beyond Low Earth Orbit, the key technologies NASA required were electric launch and propulsion technologies, long-duration closed ecosystems, aerobraking, artificial gravity, nuclear power plants for electricity generation, and hypersonic air-breathing propulsion. As it happened, many of these technologies were already under research and development by both NASA and the USAF, the latter of which had picked up with Project Timberwind where NASA had left off with the cancellation of NERVA, and which was researching SCramjet propulsion for the National Aero-Space Plane project. NASA, for its part, was hard at work investigating closed-loop life support technologies and artificial gravity. However, a growing section of NASA’s younger, post-Apollo engineers and managers found a source of disappointment in the NCS’s recommendations: if followed to their conclusion, the only fundamentally new vehicle they’d yield was a Space Transfer Vehicle, the reusable space tug for which Thomas Paine’s original vision in 1970 had called. While no one doubted the utility of such a vehicle, the 1980s had seen the resurgence of a lobby that was interested in the Moon and Mars as human destinations, and the refusal of the NCS to recommend either destination, and the subsequent lackadaisical attitude Congress had taken to funding any of the programs it had recommended, left a feeling that the other worlds would ever remain just out of reach. As one attendee at a Case for Mars Conference in Boulder remarked in 1987, “we didn’t get to the Moon when someone said ‘let’s put my lunar module on your heavy lifter.’ We got to the Moon by committing to it and designing an architecture optimized for it. If we keep designing architectures only for orbital operations, that’s all we’ll ever have.” Unfortunately, the NCS was hesitant to recommend either the Moon or Mars as immediate, near-term destinations, owing to the projected cost of an immediate, mostly-expendable effort.

    While efforts focused beyond Earth orbit remained distinctly back-burner, efforts directed towards a large, permanent follow-up to Spacelab had been ongoing since President Reagan’s 1984 direction of NASA efforts towards such a project. However, after three years, little real progress had been made. Far from the unified vision which had characterized Project Apollo or the development of the Space Lifter, the American large space station effort remained stranded for more than two years in the blizzard of studies and competing visions which had characterized the early years of the development of the Space Shuttle. A variety of factions had sprung up to critique the station’s purpose and scope. More than the usual squabbles between NASA’s centers over the division of project management, these reflected a deeper struggle over the role and goals of the station project, and the basic tools which would see it carried out. The result was slow progress along a multitude of different tracks.

    Johnson Space Center in Houston, coordinator of all manned mission operations, saw themselves as the natural home to any space station development efforts. After all, any manned station with a permanent crew would be controlled from Houston, like Skylab, Shuttle, and Spacelab before it. Moreover, Johnson had long been a focal point for the development of closed loop life support, a key challenge for a permanent space station, and one that they considered unquestionably necessary for missions to Mars. They conceived the NASA response to Reagan’s challenge as a bustling space operations center, with a crew of a dozen or more astronauts working to support laboratories, telescopes, satellite servicing, and the construction, checkout, and maintenance on a fleet of tugs usable for transferring payloads to geostationary orbit, the moon, and beyond. Components would be a mix of Lifter-sized 40-50 metric tons modules and smaller 10-ton modules hauled up by Space Shuttle and regularly rotated home, as with the LDEF or the Grumman MPEM, then assembled under the watchful eye of Shuttle-launched astronauts and augmented with further assembly conducted via EVA.

    Marshall was equally enthusiastic about seeing another massive development project come home to its natural roost at the center which had built Skylab, and supervised the design and assembly of the Space Lifter and Spacelab’s Service Module. Their proposals were largely of similar epic scope and varying role as Johnson’s, but focused more on the larger module sizes, with assembly to be conducted by the modules themselves under autonomous control to minimize risk to astronauts and the number of manned missions required to assemble the station. They even proposed that the station could be launched one large module at a time, first a man-tended power and service module, then growing over time with more habitats, laboratories, and hangars as the needs of the program drove it. The initial module would be similar in concept and function to the Spacelab Pressurized/Service Module split, and one proposal even called for using Spacelab itself as the initial home for checking out the modules as the station was constructed, before casting the older station loose once again.

    A dissenting voice on the consensus of a few large 50-ton Lifter-launched modules augmented by specialized 10-ton Shuttle lofted modules came from a faction with membership from both Johnson and Marshall, made up largely of engineers and managers working on the Wet Workshop Evaluation Mission, then aimed for space in 1987. They contended that their project could turn the vast number of expended S-IVC stages into a massive resource for space station construction and space development. Instead of a relatively small crew of a dozen or so, a few “dry” 40-50 ton modules would serve as the foundation for converting numerous larger S-IVC stages, purging them, fitting them with docking facilities, and assembling them into any number of configurations for a large station—or even for more than one in various orbits. Once this resource was tapped, the stream of S-IVC stages lofted would turn into the raw material for laboratories, spin stations, greenhouses, personal quarters, medical facilities, hangars, processing facilities to turn the expended tanks into telescopes or in-space tugs, or even into furnaces to smelt their fellows into raw materials for manifold purposes.

    All the manned spaceflight factions sought the support of the space science community. This community, though, was cooler in general on the concepts put forward for such grandiose visions, while divided into its own factions. Biologists specializing in human adaptations to microgravity were excited by the longer crew mission durations a permanent station would enable. After all, the longest missions to Spacelab possible even with the MPEM were barely more than two months, short even compared to final Skylab mission a decade earlier, much less the missions routinely flown by Soviet cosmonauts. Researchers working on experiments which required heavy intervention by astronauts and unsuited for remote monitoring and operation on Spacelab were also excited by the potential of such a station for plant growth, animal studies, and materials processing. For the moment, these researchers were forced to choose between the readily available astronaut time which came from flying in the MPEM aboard Space Shuttle free flights and the longer durations of months or years possible in the isolation of Spacelab. However, while these factions eagerly embraced the concept of a permanent manned station, other factions liked the isolation of Spacelab and the Long Duration Exposed Facility from the intervention of astronauts. For those specializing in crystal growth, physical sciences, ground imaging, and astronomy, Spacelab and the LDEF’s man-tended operation was ideal. Crews in space or on the ground could coordinate the preparation of experiments, then leave them to run on their own, taking away their variable temperatures, atmospheric requirements, and unpredictable vibrations within the station with them. While a larger platform would be valuable, it might not be if it came with the requirement to support a constant crew presence. On the whole, the space science community worried about the way that the many studies from Marshall, Johnson, and the smaller centers focused on the construction and operations of stations, with more efforts spent on the design of windows for hangars for moon tugs than on the options and applications of the laboratories scattered throughout the stations. It was, one scientist remarked, as though the station designers viewed science as some kind of substance which laboratories and instruments produced given an astronaut’s presence, good only to be brought back to the Earth for processing into budgetary funds and new space technologies. Given this perceived attitude, the scientific community was more concerned with ensuring that any new station would not draw effort away from the utilization and utility of existing platforms. This left the scientific community distinctly conservative in the discussions, more concerned with preserving the status quo of Spacelab, Shuttle free flights, and missions like the LDEF than with any faction’s concepts for the large station. As 1986 turned into 1987, the space station program continued to make slow progress in defining those items all the proposals would require, like large docking ports, large solar panel deployment schemes, and environmental control systems, but little real progress in defining a single overall architecture for the station. While NASA continued to debate the direction of American spaceflight focus for the immediate future, Russia continued to up the ante.

    Even as Raskat, Groza, and Uragan laid the foundations for a new monument to the scientific and technological prowess of the Workers’ Paradise, the old Soviet manned program began to draw to a close. In order to control costs, the venerable R-7 and the newer Proton family of rockets was scheduled to phase out as Groza took over more and more of the Soviet space launch requirements. Unlike the American Space Lifter, Groza could be scaled down to loft only 12 tonnes at a time by leaving off the upper stage and reducing the number of boosters. This meant that all but the smallest Soviet rockets (the Kosmos family, whose LEO payload was only 1.5 tonnes) could be more effectively replaced with variants of the Raskat-Groza system--and even that small remaining market was challenged when the Yuzhnoye design bureau proposed to simply fit an upper stage to Raskat in a side-mounted payload fairing. Proton, whose toxic and corrosive propellants had been raising the ire of Kazakh Communist Party officials for decades, was the first to go. Twin-Raskat Groza launches could easily and cost-effectively replace Proton for 20-ton class payloads. The Soyuz family of rockets was to be retained for a few years longer, to maintain Soviet crewed launch capability until the Uragan spacecraft were ready to pick up the torch, but no further improvements of the Soyuz design were planned. The Soyuz-TM, specially optimized for space station operations, had been cancelled earlier in the decade, though its Kurs docking radar would survive to be mounted to the last few Soyuz-T spacecraft. The last Soyuz flights of the 1980s, and of the programme as a whole, would seal their own obsolescence by providing final validation for hardware to be integrated to the Uragans.

    Soyuz T-15 was one such mission. This 50-day mission to the space station saw Leonid Kizim and Vladimir Solovyov collect experiments laid out by the previous crew, test electron beam welding techniques in low earth orbit, test a new folding girder design, and, finally, reboost Salyut to a higher orbit to forestall reentry. Though no further use of the space station was planned, Soviet planners hedged their bets against the chance of a budgetary crisis in Moscow, and left the space station in an orbit not expected to decay until the mid-1990s.

    The reboost of Salyut was not the end of the Soyuz T-15 mission, however. While they occupied Salyut, the Raskat-Groza system had taken to the launch pad again, bearing a new payload--the 40-tonne core module for the new, modular space station Mir. Injected into the same 51.6-degree orbit occupied by Salyut 7, Mir’s core module was of a brand new design, optimized for the longer and wider payload fairing of the Groza rocket. Though Mir’s life-support, power, and thermal control systems drew heavily on those tested in the Salyut program, the station’s pressure vessel was of a new design, with two axial docking ports and two more port and starboard ports. The Mir core module was designed to provide power, communications, thermal control, and crew accommodations for up to 6 cosmonauts on long-term missions, and to support two laboratory modules at a time. The laboratory modules, still under construction in 1986, were similar to the American MPEM, but designed to stay on orbit between missions. They would be carried in an Uragan payload bay, and attached to the port or starboard docking ports as needed. This would allow Mir’s scientific capability to be adjusted according to the needs and interests of researchers on Earth, and allow easy upgrades to the laboratories in the very factories in which they were first built.

    Soyuz T-15 rendezvoused with Mir on October 19, 1986, for a brief, two-week stay during which Kizim and Solovyov checked out the station’s life-support, communications, and thermal control systems. Uncooperative station docking systems being a frequent nuisance in the Salyut program, they also repeatedly docked and undocked with the station’s axial docking ports, in order to verify that the rendezvous equipment on the station was functional. The successes proved that the Kurs system did in fact allow Soyuz to dock without the station actively maneuvering to match.

    As the completion of the Uragan life-support systems dragged on, the decision was made to use up the remaining stock of Soyuz-T craft to utilize Mir in the interim. Though the Mir core module was primarily a service and habitation module, it did have some limited scientific capacity, mostly in the field of space medicine and optical earth observation. Soyuz T-16 rendezvoused with Mir on March 5, 1987, carrying Aleskander Laveykin and Yuri Romanenko, who spent 5 months aboard the station studying anti-microgravity countermeasures (including a new design of elastic resistance suit, changed exercise regimes using the new equipment launched on the Mir core module, and pharmaceutical treatments) and performing extravehicular activities to attach sensors to the exterior of the hull. They also performed basic astronomical observations (with small, simple instruments carried in their Soyuz) to test the utility of Mir’s gyroscopic stabilization system, which reduced the reaction-control propellant requirements of the immense space station, at the cost of a high electric power requirement. Among the more revolutionary innovations in life-support on Mir was a refrigeration-based CO2 scrubbing system, which cooled air until carbon dioxide deposited on a surface for collection, eliminating the need for lithium hydroxide canisters. After some initial hiccups in the third week of the mission, Laveykin and Romanenko repaired the mechanism, which would perform remarkably reliably for the remainder of Mir’s on-orbit life.

    Soyuz T-17 followed T-16 in 1988, bringing Valeri Polyakov and Vladimir Titov to a rendezvous with Mir on January 7, for a six-month stay. They continued the medical sciences experiments of the T-16 crew, and performed new ones--among their cargo was a specially-designed surgical dummy used to test first-aid techniques for microgravity. Most notable, however, was the rendezvous of the second Uragan orbiter, Kryechyet, “Falcon.” Fitted with a docking radar and life-support system, this Uragan launched unmanned on a Raskat-Groza heavy stack, carrying the first of the laboratory modules built for Mir--the KP Spektr module, fitted with earth-observation sensors and observation equipment. The first of Mir’s dedicated laboratory modules, Spektr brought a massive increase in the scientific capability of the station, giving Polyakov and Titov the ability to perform detailed studies of ground and atmospheric targets, measuring atmospheric gas concentrations and collecting infrared and ultraviolet photographs of the Earth’s surface. Polyakov and Titov also entered Kryechyet’s flight deck, measuring the atmospheric concentration there and determining that the life-support system was, in fact, functional, and clearing the way for manned launches of the Uragan orbiters in the years to come.

    While the Soviet Union slowly but steadily worked to match and in some cases exceed the progress of the American Space Transportation System and Spacelab efforts, the European Space Agency found its own launch vehicle family, Ariane, something of a disappointment. Though far more reliable than the Europa rockets it replaced, Ariane was far more expensive than the Space Lifter, particularly after the Space Transportation Corporation enacted further cost-saving measures in 1985. While Ariane certainly gave the European Space Agency the ability to launch its own scientific and civil satellites and gave France her own military launch capability, the system found very little interest outside Europe (with the exception of states like Brazil, whose attempts to develop her own satellite launch capability hindered cooperation with the US), and even the United Kingdom had chosen instead to purchase Space Lifter flights for its military payloads.

    Though many ESA bureaucrats were content to simply have an independent launch capability, and countries like Germany and Italy preferred to move on to other development programs (such as a permanent “lifeboat” escape vehicle for Spacelab, which would help enable a transition from man-tended to permanently-occupied operations and lay groundwork for future European manned spacecraft), Arianespace and CNES engineers began to study alternative rocket configurations in 1983 that would allow them to reduce costs and compete with STC’s Space Lifter. Recognizing the benefits of reusability demonstrated in the United States, but also recognizing the great strides that the ESA had made in hydrogen-burning rocket engine development and automated control systems, they explored several variants on a purely-European reusable launcher. A range of two and three stage solutions were initially examined, starting in 1982. There were as many approaches within these broad parameters as there were European aerospace firms and institutions. While most converged on hydrogen-oxygen for the core stage, there was disagreement about how to recover the core or whether to bother at all. Proposals for both the core and boosters ranged from fixed wings to folding wings to ballistic reentry to recovery of only the engines, with propulsion ranging from landing rockets to gliding to jets to turboprops, and every conceivable combination. Options for the boosters included solid-propellant (favored by some French engineers, owing to their experience with ballistic missiles), hydrogen, kerosene, hypergollics (favored by the Ariane teams), and pressure-fed natural gas (favored by German engineers based in Stuttgart). By 1984, the range of options began to narrow. The realities of launch from French Guyana forced an emphasis on either water landings (as polar orbit launches required flight directly north, over the open Atlantic), which favored ballistic or airbag landings, or very long-range powered flight to a suitable landing site (sites in the Caribbean and Canada were both considered for the core stage, depending on its exact trajectory). Pressure-fed and solid boosters both lent themselves well to water landings, but conversely their high-thrust, low-specific-impulse characteristics were best suited for the booster stages--which actually could stage close enough to the launch site to fly back.

    The logic of multi-stage rocket design began to limit the options. The hydrogen-burning core stage would be the most expensive part of the vehicle and supply most of the delta-v, so it was the most crucial to reuse. It was also undesirable to drop high-performance cryogenic engines into the ocean, so a consensus on a reusable core emerged. While the first design studies had tackled anything from 2 tonnes to 200 tonnes to Low Earth Orbit, a study of the European and global space industry’s actual needs refined the payload target down to 16 tonnes. This would give the new launcher the ability to launch larger geostationary payloads individually, avoiding the logistical headaches of arranging shared launches, while also enabling the launch of an indigenous European manned space capsule, based on the multitude of Spacelab lifeboat projects then under study. The greatest issue remaining to confront was exactly what technology was best suited to developing a reusable launch vehicle that could put 16 tonnes in Low Earth Orbit, a question whose answer eluded program managers for several years.

    Alone among the major spacefaring powers, Japan did not found her launch vehicle industry upon a ballistic missile or atomic deterrent program. By law and custom, Japan had renounced such weapons after the carnage of the Second World War. Nevertheless, Japan was quick to join the ranks of spacefaring nations, becoming the fourth nation (after the Soviet Union, United States, and France) to launch its own satellite with the launch of the Osumi satellite on February 11, 1970. Japan’s first two satellite launchers, the Lambda and Mu families, were small and simple solid-fueled rockets, modest by the standards of the gigantic boosters of the Soviet-American Space Race, but they provided a firm foundation for the development of a healthy aerospace sector.

    Unlike the French, Japan’s leaders had no illusions about retaking a “rightful place in the sun,” and so cooperation between the Japanese and American governments on space access was comparatively smooth and easy. Japan’s next satellite launch vehicle, the N-I, was based on a license-built Thor IRBM, with a new, Japanese-made upper stage, powered by a liquid-fueled LE-3 engine. The experience gained in the LE-3 development program paved the way for a whole suite of new Japanese engine development programs in the 1970s and 1980s, intended to form the foundation for a fully-reusable Japanese launch vehicle--perhaps even a single-stage-to-orbit spaceplane. Japanese researchers developed a wholly-indigenous hydrogen-burning rocket engine, the LE-5, and conducted research on a host of exotic engine designs, ranging from staged-combustion LH2/LOX engines to air-breathing rocket engines to scramjets.

    It was this dynamic and evolving Japanese aerospace sector that attracted interest from American corporations in the 1980s. McDonnell-Douglas, building on its longstanding partnership with Mitsubishi Heavy Industries, took a keen interest in the turboramjet and scramjet research being conducted in Japan, and proposed to use air-breathing engines developed by Ishikawajima-Harima Heavy Industries (whose work built on Aerojet’s research in the 1950s) in their National Aero-Space Plane proposal. Though McDonnell-Douglas did not win the prime contract for NASP, their suggestion to use a Japanese engine design stoked a sudden interest in Japanese propulsion technologies among American aerospace firms. While Japanese businessmen and government officials were reluctant to give much technical access to representatives from Aerojet or Pratt & Whitney, representatives of the more general aerospace firms (McDonnell-Douglas, Martin-Marietta, Boeing, and Grumman) had a much easier time interacting with their Japanese counterparts. American engineers witnessed static-fire tests of a variety of new Japanese hardware, and attended briefings on progress made in more exotic propulsion projects.

    The most significant incident during these meetings came in 1986, when Martin-Marietta Vice President of Technical Operations Norm Augustine met with Yohei Mimura to discuss possible Japanese use of Martin-Marietta’s Reusable Launch Vehicle design. To Augustine’s surprise, when he mentioned that Pratt & Whitney and Marshall Space Flight Center had both performed design studies on staged-combustion LH2/LOX engines, Mimura alluded to a staged-combustion-cycle engine already in development and undergoing breadboard component testing, the LE-7. Inquiring further, Augustine and other Martin-Marietta executives learned that Mitsubishi Heavy Industries had been hard at work on a staged-combustion-cycle engine of indigenous design since 1984, intended for the all-Japanese replacement of the N-II rocket. Though they were relative latecomers to cryogenic rocketry, Mitsubishi’s engineers had made great strides in integrating cutting-edge computational fluid simulations to their design process, promising a radical reduction in the cost and development time of the new engine, which they planned to have on the test stand by 1989. They also benefitted from great improvements in metallurgy made between 1970 and 1984, giving them access to better steel and titanium alloys than Pratt & Whitney or Rocketdyne engineers could assume in the waning days of the Apollo program. While they lacked the experience of Soviet engineers, Mitsubishi’s engine designers were the equals of any of their American counterparts.

    Japan’s leading aerospace institutions, including NASDA, NAL (the National Aerospace Laboratory), and ISAS (the Institute of Space and Astronautical Sciences), had been intimately involved in evaluating the propulsion systems under development and study by Mitsubishi, Ishikawajima-Harima, and Japanese universities. Inspired by the success of the American Space Lifter and now by the Soviet demonstration of the Raskat-Groza system, Japanese engineers and executives had proposed a variety of reusable launch systems, ranging from a miniature Shuttle on top of the proposed H-II expendable rocket to a reusable suborbital sounding rocket to a fully-reusable, air-breathing SSTO program. Martin Marietta’s research during the CRLV program, published openly with the American Institute of Aeronautics and Astronautics, had shown very convincingly that a reusable TSTO would have a lower development cost and comparable operating costs to an SSTO of similar performance--ultimately, the cost of integrating two reusable stages was modest compared to the cost of simply turning the stages around between landing and launch. Martin-Marietta further challenged the conventional wisdom by pointing out that the payload mass fraction of a ballistic, vertical-landing spacecraft could, in fact, exceed that of a winged or lifting-body vehicle, as the horizontal-landing vehicles needed additional structural support to support greater side-loads, whereas vertical-landing craft were already designed to handle axial loads. As a result, a small but growing fraction of Japan’s aerospace establishment was convinced that a fully-reusable, two-stage vehicle would be the most economically viable way forward for Japan’s launch industry. This segment only grew with every milestone passed in the checkout of Martin-Marietta’s Terminal Descent Demonstrator as it prepared for its first flights. Mitsubishi’s revelation of their LE-7 development program had been far from unintentional--rather, it was the first suggestion of an exchange of MHI’s new high-performance rocket engine for Martin-Marietta’s skill with vertical rocket landings.

    However, there remained among NASDA’s leadership concerns about committing to an undemonstrated architecture like that proposed by Martin-Marietta, and a reluctance to commit to such a program alone. Augustine’s visit to Japan was an opportunity to measure the possibilities for a partnership with the American company, to evaluate their interest in Japan’s propulsion technologies and the possibility of a relationship similar to that which Mitsubishi in particular and Japanese aerospace in general enjoyed with McDonnell-Douglas. Ideally, NASDA and Mitsubishi wanted to leverage Japan’s strengths in rocket engine development as much as possible, in such a manner that, if the partnership fell through, they would still be able to pivot back to developing their own RLV or returning to the expendable H-II design still under consideration.

    The partnership would not be identical, however--whereas the earlier relationship had amounted to Mitsubishi license-building a fully-developed American rocket stage, a joint Japanese-American TSTO would involve the development of new intellectual and physical capital that would not be the sole property of either firm, and there was the possibility of international arms-trafficking regulations keeping such a joint venture out of lucrative government and commercial satellite contracts. A partnership to develop the new vehicles would require the creation of a new, jointly-owned venture. There was precedent for such an organization--in the 1970s, General Electric and Snecma (of France) had created CFM International to manufacture the CFM56 turbofan engine, which used parts made in both the United States and France. CFM International’s engines were manufactured in both Ohio and France, depending on the final buyer for the engines, and both Snecma and GE profited from the exchange of technology and the new markets opened by operating on both sides of the Atlantic.

    As Augustine and other Martin-Marietta executives met with their counterparts at Mitsubishi Heavy Industries and with regulators at NASDA, the first outlines of a similar joint venture began to take shape. As 1986 gave way to 1987, an agreement emerged between Mitsubishi Heavy Industries and Martin-Marietta to found a new joint venture--Trans-Pacific Launch Industries, which would jointly develop a TSTO reusable launch vehicle, powered by Japan’s LE-7 and LE-5A rocket engines, but with an airframe and control system developed by Martin-Marietta. The completed vehicles could be assembled in either the United States or Japan (indeed, most likely both, as the CFM56 engine was assembled in both the US and France), while Martin-Marietta retained control over the airframe production line and Mitsubishi focused on the engines. Mitsubishi would supply over 50% of the development capital, while Martin supplied its experience with the TDD.

    Formally incorporated in 1987, TPLI would spend the next several years pushing the TDD’s landing software to greater lengths and evaluating designs for the reusable upper stage, while Mitsubishi worked on finishing the LE-7 development process and developing the improved LE-5A variant of its LE-5 rocket engine. In addition to the staged-combustion cycle, the LE-7 had to be capable of deep throttling and very reliable restart in flight, stretching its development cycle into the early 1990s.

    American dominance in the field of reusable rockets was no longer unchallenged: the Soviet Groza system was the first real competition to the Space Transportation System, and Europe, Japan, and even commercial firms were taking the demonstrated benefits of reusability as a pathway for the future of space launch and operations. While this challenge spurred new discussions over the lack of major American space station development or the failure to make a broader plan for the use of Lifter for the development of space, the presence of another competitor in the race only drove home that if NASA was no longer unchallenged, it was unimpeachably dominant. The program had made its 50th launch in 1984, then the 75th mission had inaugurated 1986. Now, as the program closed in on its 100th launch, it was flying as many as 18 missions a year. The main barrier to higher launch rates wasn’t the system’s capabilities but a paucity of payloads, even as the size of commercial satellites grew to fill the Lifter’s Multiple Launch Adaptor. While the Soviets struggled to clear the hurdle of launching two manned Uragan flights in one year, payload schedulers at NASA, the DoD, and the Space Transportation Corporation made plans for pulling off a similar feat within as little as a week, and to demonstrate two critical roles for the Space Shuttle in the process.

    For almost two years, engineers at NASA’s Marshall and Johnson space centers had been collaborating to turn the principles of wet workshop implementation, as developed originally for Skylab’s earliest ancestors, into practice for the Wet Workshop Evaluation Mission, often known by the shorthand “Wetlab”. Specialized modifications had been made to an S-IVC diverted from the main production flow, and a new docking module had been fabricated based on Spacelab and MPEM derived hardware, intended to fly inside the Shuttle for the mission. The S-IVC was fitted with metal mesh partitions and brackets to mount hardware to on orbit, and engineers had spent months designing and testing the ways to fit all the critical systems of a temporary space station into the confines of the Shuttle and the Docking Module. Referencing a new furniture company which was growing around the world, one NASA engineer described it as “trying to design Spacelab as built by IKEA.” However, finally, the hardware was ready and a crew was assigned for training and flight. With an eye to the Public Affairs Office, the mission was assigned the much-anticipated STS-100 mission designation.

    At the same time NASA was seeking a public spectacle for their test of a new approach to space operations, the National Reconnaissance Office was eyeing its own new capability. Their KH-12 LUCID electro-optical satellites, with their massive 168-inch main mirrors, were a major improvement over previous KH-11 and KH-9 satellites. However, their capacity came at a price tag staggering compared to previous generations of optical satellites. One of the benefits of the electro-optical design was that film capacity no longer would limit the lifespan of these monsters, but other elements could: failing solar arrays, motors, and batteries, malfunctioning gyroscopes, aging avionics. Moreover, the rapid advance of digital technologies even since the introduction of the KH-11 in 1976 meant that the state of the art for detectors, storage, and controls for satellites had advanced staggeringly even since the KH-12 design was frozen for production in 1983. As the satellites orbited, their capabilities would slowly erode while the state of the art lept ahead.

    However, unlike the smaller KH-8 or KH-9 satellites of old, the KH-12 was too expensive to simply dispose of and replace. As Space Shuttle advocates had promoted, there was another way. In 1982, the STS-24 mission to repair the Solar Maximum Mission had demonstrated the repair and enhancement of a flying mission with the assistance of astronauts, and the lesson had not been missed by the KH-12 design team, nor those of their civilian counterparts working on NASA’s Space Telescope project. As the Space Lifter enabled the size and capacity of these two optical systems, the Space Shuttle would allow both to be serviced on orbit. Detectors, avionics, gyroscopes, batteries, and more were examined during design with an eye towards future visits by astronauts on EVA. Quick-connects were developed to link systems intended to be removed and replaced by crews wearing EVA suit gloves and using vacuum-rated tools. Handrails and access panels dotted the outside of the satellites, unlike the bare metal skins of previous generations. Now the planning would pay off.

    Two years after its first launch, the time was approaching for the first LUCID platform to be serviced. While west coast Space Shuttle launches typically received less attention than those from Kennedy Space Center, the DoD sought additional shielding from the public eye as a critical national security asset was brought in for a tune up. The first LUCID servicing mission was assigned mission slot STS-101. The planned launch date just days after STS-100 would allow the mission to hide in the public interest NASA’s PAO was focusing on Wetlab. Not for the first time, civilian missions from NASA would serve as cover for the activities of the NRO. Also not for the first time, the best laid plans would go awry.

    As NASA’s Public Affairs office drummed up attention on the temporary second American space station mission and the hundredth flight of the Space Lifter, the near-simultaneous launch of a second Shuttle from a second coast west was just one more detail. As intended, the absence of mission details for Resolution was overshadowed by a rush of stories on the mission and crew of STS-100. While the eyes of those casually interested in spaceflight focused on Florida, Intrepid was readied in California. However, clouds were on the horizon, both proverbially and literally. A break of bad weather was the first interruption in the schedule, with both missions slipping a week to wait out storms and unsatisfactory winds in Florida. However, in the meantime, further inspections of the STS-100 showed a potential concern with an umbilical plate carrying liquid oxygen to the Space Lifter Independence. Destiny’s mission was delayed several more days as the ground crews tested, inspected, and finally removed the entire assembly. It would require servicing before flight. While awaiting a NASA decision on how long the delay might be, Vandenberg launch operations eyed a streak of anticipated bad weather in California. Waiting for Independence and STS-100 to be ready for Wetlab might mean the delay of STS-101 by more than a month past its originally scheduled date if the close alignment of flights was to be preserved.

    Ultimately, leadership made the decision: Wetlab had absorbed enough attention that Resolution could carry out her servicing mission. While waiting for the originally planned alignment would offer minor benefits in mission secrecy, it would require unwarranted delays. Not for the first time, a Vandenberg launch and a Cape launch would switch their originally planned order. As with the several times the situation had happened before, the STS mission number would stay attached to the two missions even as they switched places. Having the launch sequence in order was of minor benefit given the effort involved in changing hundreds of pages of typewritten documentation, mission patches, briefing notes, and more. While the public continued to take in news on the STS-100 mission to test a new type of station, the actual hundredth launch, STS-101, launched from Vandenberg into thick afternoon clouds on July 23rd, 1987. Less than thirty seconds into the flight, Intrepid carried Resolution through the lowest cloud layer, shrouding the mission from the view of the few spectators who had braved intermittent rain showers. Little more was seen before Intrepid’s return twenty minutes later to a landing on Vandenberg’s runway.

    As always, schedule slips were perverse. Almost as soon as Resolution's schedule was no longer tied to it, NASA and STC engineers were able to diagnose and resolve the issues with Independence's umbilical plate more quickly than anticipated. Independence and Destiny belatedly lifted off just two days into Resolution’s flight, cutting into a cloudless sky in front of thousands of sightseers. The mission reached orbit without incident, the aluminum protrusions within the hydrogen tank having no significant effect on the fluid distribution in flight. The Orbiter, after separating from the upper stage, opened its payload bay, exposing the Docking Module, which filled most of the small bay’s volume. Using the Canadian-built robotic arm, the crew attached the Docking Module to Destiny’s own docking ring and unfurled the small solar array. On the second day of the flight, following a complete check-out of the Docking Module and remote venting of the S-IVC’s residual propellant, the crew docked Destiny and the Docking Module to the mating attachment fitted to the top of the S-IVC’s hydrogen tank. After pressurizing the tank with compressed oxygen and nitrogen, the crew, equipped with eye protection, dust masks, and head-mounted flashlights, entered the cavernous volume of the S-IVC’s hydrogen tank.

    Not since Skylab 4 had any crew had so much elbow room in a spacecraft. Pulling themselves down the length of the tank by handholds and mesh floors, the crew inspected all the brackets and attachment points inside the vehicle. Everything seemed to have survived both the launch and exposure to the hard cryogenic propellant the tank had been designed to hold. In one of the more enduringly popular images from the Shuttle program, Commander Charles Bolden, illuminated only by the light filtering in from the Docking Module and his own head-light, jumped gently from the oxygen tank’s bulkhead up the entire length of the hydrogen tank, reaching the Docking Module almost 10 seconds later.

    The crew quickly set to work fitting the S-IVC out as a habitable volume. Attaching fluorescent lights to the wall-mounted brackets, they ran power cables from the Docking Module through the open hatch, and set up fans to circulate air between the two spacecraft. Coolant pipes were also run in, to help radiate the crew’s body heat and the heat given off by the electrical systems. Experiment pallets were handled in through the narrow docking hatch, and secured along the walls. This mission had few actual scientific experiments--the pallets were mostly empty--but they proved the concept of moving equipment from the tight confines of the Orbiter to the much roomier Workshop.

    While Destiny’s crew could set to work immediately, it had taken most of Resolution’s lead to even reach rendezvous with the target LUCID platform. Shuttle had always used the massive delta-v capacity required by its integral pusher abort engines to provide some of its own circularization and for orbital maneuvering. Resolution took this capacity to a new level on STS-101. Instead of boosting payload, the Shuttle carried a smaller payload of barely four metric tons from its initial low, sun-synchronous polar orbit into the highly eccentric orbit of the KH-12 satellites, skimming the lower bounds of the Van Allen belt at just under 1000 km apogee. Even raising its apogee by more than 700 km would leave ample margin to reverse the maneuver for return. Still, the mission in its cloak of secrecy felt remote from Earth as they crept into visual range of the LUCID platform. The KH-12 loomed large, more like a space station than the small satellites Shuttle had previously serviced; the approach to grapple had more in common with docking to Spacelab than the Solar Maximum Mission or recovering the LDEF. Regardless of the challenge, Resolution’s commander, Richard Lawyer, managed it handily. The crew latched onto the satellite and went to work.

    On this early mission, the key capability was to demonstrate any servicing at all and conduct basic inspections impossible by telemetry: future missions using the boosted capacity of the Dual-Engine Upper Stage would be required for major overhaul of the primary instruments. Still, they were able to conduct some small maintenance tasks of great value. One of the KH-12’s gyroscopes had failed in late 1986, and Resolution had brought a spare. Working together, Lawyer and Mission Specialist Henry Hartsfield extracted the failed unit and installed the replacement. The mission wasn’t solely tasked with upkeep on LUCID, though. On their next EVA, they extracted and replaced one of the platform’s magnetic tape memory modules with one of nearly double the storage capacity. These modules were used to cache images during mapping passes, as data came in from the optic’s CCD arrays faster than it could be downlinked back to Earth. By enhancing the capacity, LUCID would be able to take more pictures and provide better combined imagery of areas critical to national security. The upgraded storage had already been installed on the ground in the latest KH-12, launched earlier in 1987, but now it would be installed on the existing LUCID constellation. The other major task was one in which the National Reconnaissance Office took particular pleasure: demonstrating the capacity to swap some of the platform’s imaging systems. On this flight, they would be pulling the lightest and smallest of the platform’s instruments: the same color mapping camera which had taken the images infamously leaked to Jane’s. The new system, likewise mounted already to the newest LUCID platform, offered better resolution thanks to a revised CCD array. The leak now would constitute disinformation on actual LUCID capabilities, and the successful swap paved the way for upgrades of other optics once the DEUS became available to boost servicing mission payload.

    While the crew of STS-101 were up to their elbows in billions of dollars of critical national-security hardware under near-total media blackout, the crew of STS-100 continued to create an ongoing spectacle aboard Wetlab as they tested variations on the proposed uses of wet workshops as much as possible within the limited mission capacity and duration possible in a Shuttle freeflight without an MPEM. Most excitingly to engineers planning missions to Mars and other destinations, the fifth mission day saw Ehricke’s original vision vindicated when Destiny used her attitude control thrusters to impart a very slow spin to the docked assembly. Though the center-of-mass of the spacecraft was very close to the Orbiter, the sheer length of the S-IVC’s hydrogen tank meant that even the 1-rpm spin rate achieved produced noticeable acceleration at the oxygen tank’s upper bulkhead. Cameras placed there showed objects falling gently to rest on the bulkhead, and the crew, when they ventured down to provide their own observations, reported feeling a light but noticeable weight.

    The S-IVC was de-spun on the sixth day of the mission, shortly before Destiny separated and returned to Earth. Returning the Docking Module to the payload bay for possible future reuse, the crew separated from the upper stage and deorbited the Shuttle. Several days later, over the Indian Ocean, a pack of solid rocket motors fitted to the base of the empty stage fired, lowering the stage’s perigee to under 100 kilometers over the South Pacific. It joined the rest of the Low Earth Orbit S-IVCs at the bottom of the ocean just hours after. Resolution had made her return back to Earth without trouble two days earlier, carrying with her the hardware removed from LUCID.

    The Wet Workshop experiment had been a technical success, but it had also revealed the shortcomings of the Wet Workshop concept. At the end of the day, the crew of STS-76 had lived and worked in a big, empty aluminum tank. Any attempt to outfit such a stage would have required a much bigger equipment module than the Docking Module or the Orbiter Destiny--there was simply no room in the spacecraft for enough equipment to actually utilize the vast bulk of the hydrogen tank. Compared to the experience of Spacelab four years earlier, the Wet Workshop required much more work to set up and had less ultimate utility. While an Equipment Module could have been built to house equipment for a functional Wet Workshop, such a module would, essentially, be a Space Station itself, rendering the Wet Workshop redundant.

    The one unmitigated advantage that the Wet Workshop had over competing Space Station proposals was in the ease with which its length enabled artificial gravity experiments. Though the 1-rpm spin rate of STS-100 allowed only 3% of a G at the base of the hydrogen tank, a 4-rpm rate could provide half a G, while a 5-rpm rate would provide well over 80% of a G--enough to mitigate the deleterious effects of microgravity that had been apparent since Skylab. While this actually acted against the Wet Workshop as an Earth-orbiting Space Station (as it would render the microgravity science experiments then in-vogue impossible), it kept the Wet Workshop popular among planners of interplanetary missions. Most notably, NASA’s Design Reference Mission 1.0 for human missions to Mars would feature an S-IVC retained for the duration of the mission and spun up to address concerns about bone deterioration and interpersonal tensions among the crew.

    While Wetlab had added fuel to the fire of debates over future NASA stations and beyond-Earth exploration, Resolution’s LUCID servicing mission had much more direct impact in the near term. Both missions had demonstrated the capabilities of Shuttle for major overhauls and operations on space hardware, but while Endeavour’s crews had worked almost entirely in shirtsleeves, assembling small hardware and moving materials, Resolution’s four-man crew had spent days trading off gruelling EVAs. Also, Wetlab was for the moment a one-off demonstrator. The STS-101 mission profile was one Resolution and other polar-launched orbiters were due to repeat many times over: a regular servicing schedule for the planned four-satellite KH-12 constellation would require such a mission to launch every year. The demonstration of the repair and even improvement of a delicate optical instrument already on-orbit was also groundwork for Hubble. Though the secrecy involved with LUCID operations meant that the sharing of details was challenging to arrange, NASA had assisted in developing the mission profiles and training for STS-101, as they supported all USAF Shuttle missions, and was able to learn key lessons for Hubble, still more than a year from launch.

    The dual successes of STS-100 and STS-101 in 1987 were planned to be followed in 1988 by another feather in the cap of NASA’s unmanned science program, managed through the Jet Propulsion Laboratory. Magellan lifted off on the STS-116 on April 6, 1988, carried on a Lifter-Centaur stack. The Lifter, Liberty, separated neatly from the S-IVC second stage on-time. As they pitched the booster over to point the heavily armored ventral surface forward, to protect the rest from the flame of the second-stage engine, Commander John Blaha and Pilot Richard Richards, both veteran Lifter pilots who had made the trip half-way to orbit before, waited for the slight acceleration that would indicate the successful ignition of the J-2S-2, waiting to complete the flip for the descent burn.

    It never came. The RS-IC, nose-up, coasted in free-fall as the seconds ticked by.

    “Houston, be advised. We have no second-stage backscatter. Say again, we have no second-stage backscatter.”

    "Copy that, Liberty, we are working it.” Back on on the ground, the voice of the Flight Director came over the main loop, talking over the ongoing discussion between the Lifter and CapCom. “All operators, contingency procedures in effect. Booster operators, watch your data. All other operators, secure all notes. GC, lock the doors." Even as the understanding of the mission failure percolated through the Space Transportation System’s vast network of control and support teams, Launch and Landing Control at Kennedy Space Center stoically prepared for the Lifter’s Return to Launch Site.[/I]
     
    Chapter 11: Retropropulsion
  • “Flight controllers here looking very carefully at the situation, obviously a major malfunction……..We have confirmation from the Flight Dynamics Officer that there has been a failure of the upper stage. The crew of the Space Lifter Liberty are continuing to prepare for their return to Earth.” -- Public Affairs Officer Transcript, STS-116 Mission
    Chapter 11: Retropropulsion

    110 kilometers above the North Atlantic, the Space Lifter Constitution drifted slowly, lazily, its flat underside pointed out at the stars, its rounded dorsal hull and immense rudders down to Earth, while keeping its engines pointed east. As the Lifter reached the peak of its trajectory, the onboard guidance computer calculated the precise orientation and duration of the burn that would be necessary to return Constitution to her launch site. As the seconds ticked by, the peroxide attitude-control thrusters on Constitution’s nose and tail fired softly, gently, keeping the Lifter pointed at the correct azimuth.

    Then the center F-1B restarted, together with two of the outboard engines, pushing Young and Crippen back into their seats with over 4 Gs of acceleration, as the Lifter turned itself around, bleeding off the speed it had husbanded through its flight so far and then pushing itself back toward Florida. The cabin shuddered as the remaining propellant rushed through the turbopumps into the combustion chambers, the mass of the booster dropping slowly as kerosene and oxygen were driven out of the tanks at phenomenal rates. 15 seconds after the burn began, there was a sudden jerk--the outboard engines cut off to control acceleration. The center engine kept burning, throttled up, in fact, at a more modest 2.5 Gs, climbing slowly, slowly, until it, too, cut off, with all but the vapors in the propellant tank spent.

    For a brief moment, Young and Crippen were back in microgravity, the earth slowly, imperceptibly, growing larger in their windshield. Then the guidance computer moved on to the next step in its algorithm, continuing the electromechanical dance it began at launch. Valves opened in the nose and tail to release hydrogen peroxide onto a catalyst bed, where, in a burst of heat, it dissociated into steam and hot oxygen gas, which blasted out into the near-vacuum of Earth’s thermosphere. The valves opened and closed in unison, to impart a precisely calculated momentum to the Lifter. Seconds later, the great vehicle was again pointing in the direction of its own travel, its trajectory altered, steeper, but with a slower atmospheric entry speed, and a point of impact considerably closer to Florida than it had been. Like exactingly trained ballet dancers, the valves on the opposite side of the vehicle repeated the movements of their counterparts, cancelling every kilogram-meter-squared-per-second that the earlier bursts of gas had imparted, zeroing the Lifter’s rotation and keeping its nose pointed straight down the line of its descent. For now, the great ship yet operated beyond the Karman line, where the laws of aerodynamics give way to a much purer expression of Newton’s Laws. The thin wisps of air curling around the ship’s wings acted more like discrete clumps of atomic oxygen and nitrogen and helium than a continuous fluid. But soon, they would thicken, and their grasp on the ship grow. The coming struggle would force man and machine alike to the very edge of their capabilities.


    Despite the frantic efforts of mission controllers to salvage the Magellan probe in the minutes after the failure of the J-2S-2 engine to start, the spacecraft and its upper stage soon reached their apogee and began falling back to Earth. When it became apparent that the spacecraft could not complete its mission, controllers ceased attempts to light the engine belatedly to avoid risk to the returning Lifter booster. After a safe gap was opened by the Lifter’s retro burn, range safety officers remotely triggered the self-destruct mechanisms on the S-IVC, activating a number of shaped-charge explosives that destroyed the liquid hydrogen and liquid oxygen tanks, whose contents swiftly boiled in the near-vacuum of Earth’s thermosphere. The small chunks left of the S-IVC and its payload reentered Earth’s atmosphere and disintegrated further shortly afterward, and were torn into ever-smaller fragments as systems built for the forgiving vacuum of space were subjected to the phenomenal loads of hypersonic flight.

    Even before the stage was destroyed, engineers across the United States, at Kennedy Space Center, Johnson Space Center, and Marshall Space Flight Center, and at Rocketdyne’s Canoga Park headquarters in California, were poring over the telemetry the stage beamed back in order to determine exactly what had gone wrong. Over the course of the next several months, this telemetry would be combined with intensive scrutiny of all records of the hardware that had been mounted on STS-116, and a regime of static tests of other S-IVCs to identify exactly what had malfunctioned. Every moment for months predating T-0 to the recovery of washed up fragments of hardware on Florida beaches in the weeks following the failure was collected to piece together the cause of the failure that had happened on April 6, 1988.

    While the engineers worked to identify why the S-IVC had failed to complete its mission, NASA and USAF managers began coordinating with their counterparts at Martin-Marietta to bring the mothballed Titan launch pads, LC-40 and LC-41 at Cape Canaveral and SLC-4E at Vandenberg Air Force Base, back online. Though a previous Lifter flight, STS-113, had launched the final KH-12 just a few months before the Magellan failure, satisfying the Department of Defense’s need for the very high-mass optical reconnaissance satellites, the USAF still had a manifest of electronic intelligence and general communications payloads to loft--ones that, depending on how long Lifter remained out-of-service, might have to go up on Titan III. For Martin, deep in planning with the newly-formed Trans-Pacific Launch Industries (TPLI) for their own reusable vehicle, the contracts to activate the Titan III contingencies was a mix of benefits and drawbacks: engineers had to be pulled from design meetings to dust off stages which had lain preserved in warehouses for years.. At the same time, the contract brough important revenue to Martin at a time when TPLI was gearing up for major investments. Thus, even as the Space Lifter stand-down helped reinforce Martin’s lobbying to politicians about the benefits of a second (even partially) American reusable launch vehicle, Martin worked diligently to restore operational status to a rocket many had written off as condemned to the history books.

    Space Transportation Corporation’s commercial customers like Geostar, Intelsat, and a host of foreign companies had their own back-ups planned. Though Europe’s Ariane was not nearly as powerful as Lifter, and somewhat more expensive even so, it had a crucial advantage over the Lifter system in 1988: it was operational. While Lifter stood down, Ariane won over half a dozen new payloads--three Intelsat geostationary communications satellites, a Swedish communications satellites, a Japanese communications satellite, a Japanese meteorological satellite, and a British communications satellite named Skynet. Though the increased revenue was a welcome bonus to Arianespace as it worked to bring its new reusable launch vehicle from the drawing board to the runway, no one at Arianespace or the European Space Agency was under any illusion that it would last--sooner or later, they knew, Lifter would be back, and then Europe would be playing catch-up again. Worse, even the newer Ariane 2/3 family was incapable of lifting many of the satellites which had been originally manifested for Lifter. Some commercial customers began to demand that if the stand-down went on beyond some time, STC should work with the US government to make the USAF’s husbanded Titans available for commercial payloads that STC could no longer deliver.

    As the commercial launch market adapted to Lifter’s indefinite stand-down, and the US government brought its handfuls of stored Titans out of storage, the initial tension at NASA and STC began to give way to a sense of relief. Though it had been over twenty years since that horrendous winter night, many NASA managers, particularly the older ones who had actually worked for the program in those days, could not shake the specter of Apollo 1. It quickly became clear that the cause of the accident had not been unique to the payload--the failure that splashed Magellan into the western Atlantic could have just as easily put a Shuttle crew into the unenviable position of having to either maneuver around for a Return to Launch Site abort or ditch into the ocean, far from any naval recovery force. Though the Shuttle was rated for a suborbital reentry, and though the crews were all trained in mid-air evacuations, no one wanted to put that training to the test.

    As much, then, as this failure vindicated the arguments made by Boeing’s engineers all the way back in 1971, that the Interim Semi-Reusable System was safer than the competing Thrust-Augmented Orbiter (TAOS) model because it did not necessarily need to carry crew all the way to orbit, it put the entire Space Transportation System under an uncomfortable congressional microscope. In one of his last major initiatives before retirement, Wisconsin Senator William Proxmire took the opportunity to criticize the US space program as an exercise in corporate welfare for Boeing and McDonnell-Douglas, citing a “history of corner-cutting predicated on a nutty fantasy of space industrialization,” and criticize the Reagan administration for putting control over Lifter and the S-IVC under a private corporation. Though Proxmire did not end up having much say in the investigation (having already announced his retirement and endorsed fellow Democrat Herb Kohl for the upcoming 1988 election), his criticisms set the tone for the inquiries that would follow.

    As vicious as Proxmire and his associates in the Senate could get, however, their influence over NASA and STC remained limited by the most crucial difference between Magellan and Apollo 1--no one had died. As NASA’s internal accident investigation procedures took effect and a team of NASA and STC engineers and managers sat down to identify the cause of the failure, they could count on relative inattention from the public and the President taking a fairly hands-off approach.

    Apollo veteran and Lifter pilot John Young, then Head of the Astronaut Office, was named Chairman of the Magellan Review Board on April 17, 1988. Like NASA’s last major accident review board, that for Apollo 13, the Magellan Review Board was staffed by astronauts, administrators, and USAF officers. For two months, the Review Board zeroed in on the cause of the accident and determined exactly why it had been allowed to happen. Within hours of the launch failure, it became apparent that the problem lay with the J-2S-2 engine on the S-IVC stage, which had apparently begun its start-up procedure, but had not completed it.

    As more telemetry was analyzed, STC also returned two of the lost stage’s batch-mates to the test stand at Stennis Space Center. The lost stage, S-IVC-116, had, like most S-IVCs, never been fired after the installation of its engine. The J-2S-2 had been fired by Rocketdyne at its Santa Susana test facility, but the completed stages were not generally fired after engine installation. This cost-saving measure had been implemented early on in the program, and had been planned for second-run Saturn Vs before that program had been terminated. When subjected to full-duration testing at Stennis, neither S-IVC-117 nor -118 seemed the least bit flawed. Whatever had caused S-IVC-116 to fail, it had been unique to that engine, or to the marriage of that engine to that stage--and the engine itself had shown no anomalies when it was first fired at Santa Susana in 1986.

    Following the trail of paperwork, Rocketdyne and McDonnell-Douglas engineers meticulously examined the history of every part that had gone into the engine and propellant tanks that made up S-IVC-116. Rocketdyne’s engineers finally identified the issue 43 days after Magellan’s loss, tracing it to a failure of Augmented Spark Ignition system on the engine. An electrical connection between the ASI and the engine’s control board had been improperly secured--whether through a calibration failure on the torque wrench used to fasten the bolts or a mistake on the responsible technician’s part, it had been sturdy enough to take the static test at Santa Susana, but not enough to survive the stresses of first-stage flight. The faulty connection led the ASIs to light fractions of a second later than they should have, when the combustion chamber contained more propellant than it was designed to. The result was a “hard start,” or, as such incidents were sometimes known, a “hardware-rich combustion environment.” The stage’s control systems had noticed the excessive build-up of pressure in the engine and closed the propellant feed valves, but by then the resultant small explosion had damaged both the injector plate and the ASIs beyond further operation. It was a failure that could have happened at any point in the Lifter program, but had only shown itself on this flight. The failure raised questions about what other failures could have slipped past quality control checks at Huntington Beach. Static fire testing of the stage might have revealed the failure, or more thorough testing, but the former had been deemed an unnecessary expense early in the Space Transportation System’s development program, and the latter were being slowly reduced through the years as the S-IVC continued to perform reliably and STC hunted for ways to reduce the stage’s manufacturing and test costs.

    The Review Board also uncovered a somewhat lax safety culture at STC, which had been under pressure to ramp up its launch rate in 1987 and 1988 in response to the growing number of orders and the planned ramp-up of the American civil manned space program. Though the Magellan Review Board did not comment on it, accounts and memoirs published in the 1990s reveal that the organization was also attempting to proactively counter the possibility of cheaper competitors in the near future. As former USAF General James Abrahamson, former NASA Associate Administrator and then-Director of the Strategic Defense Initiative, wrote, “We pushed STC to ramp up in preparation for the maturation of SDI, but what really lit a fire under them were proposals in 1987 from the Soviets that their aerospace sector would be reorganized under Perestroika, and that they would start selling launch services themselves. That and the European progress on their Ariane successor got them going more than we could--for the first time in almost a decade, Lifter had real competitors on the horizon.” STC moved to launch more often and reduce costs further, to assure its continued dominance of the global launch market. Though the Magellan Review Board did not comment on every reason, it did conclude that quality control at STC had slipped since the start of the decade, and that a culture of arrogance had taken hold. STC’s rocket engines, after all, dated to the early 1960s or late 1950s, and had been flying for twenty years--a general sentiment had emerged that anything that could go wrong already had.

    On July 22, 1988, the Magellan Review Board submitted its draft findings to NASA Administrator James Beggs, concluding that the damaged ASIs were to blame for the failed launch. The Board made a number of quality-control regulations for Rocketdyne and STC to implement. Somewhat controversially, the decision to not static-fire the completed S-IVC stages was not noted as needing to be reversed. The Review Board concluded that such testing would not have caught the failure, or indeed any other failure they had identified as particularly likely. The most likely cause of a failure that such static-testing would prevent, foreign object ingestion by the rocket turbopumps, was already effectively countered by the use of wire meshes in the fuel and oxidizer feed lines. At the end of the day, concluded the report, some failures could only be checked by flight or by painstaking inspections of every bolt on the spacecraft. While a static fire might look reassuring, it would not necessarily prove anything that previous tests did not. Instead, issues like the STS-116 ignition failure could be better caught by more rigorous quality and process control, with more extensive testing of the systems of the integrated stage short of actual firings.

    The Magellan Review Board concluded that almost every quality control issue they identified could be addressed through simple procedural changes at Rocketdyne and STC--better tracking of tools, more frequent inspections--and that in any event the upcoming Dual-Engine Upper Stage (DEUS) variant of the S-IVC, with its second J-2S-2 engine, would provide sufficient redundancy that most missions could be completed even with the failure of one engine. The Board recommended that Lifter operations be suspended until DEUS stages were ready for flight, a very lax restriction on the system all things considered; DEUS was, by that point, on-track for a first flight in early 1989 anyway. As Richard Truly, a Lifter pilot who had taken a management position at STC after leaving the astronaut corps, wrote in his memoirs, “We got lucky. If we had to lose a payload, there was no better time than 1988.” Shaken, but still dedicated to their tasks, NASA and its contractors set to work preparing the Space Transportation System for its return-to-flight in spring of 1989.

    The loss of Magellan, however, kicked off a small storm of controversy both within and outside of NASA, centering on whether the agency had been right to spin off Lifter operations to STC in the first place, whether the Interim Semi-Reusable System architecture had been the right choice all those years ago, and, as the dependence of Spacelab, Shuttle, and NASA’s flagship unmanned programs on Lifter was thrown into sharp relief, exactly how NASA should go forward and face the last decade of the second millennium.

    Senator William Proxmire of the Senate Armed Services Committee (almost certainly unwittingly) helped lay the foundation for NASA’s new direction when he arranged a series of hearings of NASA, USAF, and STC managers in early fall 1988. The most infamous political enemy of the human spaceflight program, Proxmire had made a name for himself by criticizing government waste (particularly on scientific research he found frivolous) and excessive military spending. The temporary stand-down of the Space Transportation System presented a golden opportunity to pin a Golden Fleece Award on a program that seemed tailor-made for him.

    In his capacity as a member of the Armed Services Committee, Proxmire summoned STC Chairman Harry Stonecipher to testify before the Committee. Proxmire took aim at STC’s Launch Services Contract with the Department of Defense, criticizing the company for using the hardware financed by that contract to operate a commercial launch service, and doing a bad job of that to boot.

    “So, tell me. I have here this report from NASA, your biggest client. They say you took those funds, failed to pay overtime, ran your operations to the bone after every red cent, and then managed to destroy a multi-million dollar piece of NASA property because of a $25 wrench. Why should we trust that you will fix this boondoggle, that you will do anything different in the future? Why should we trust that you can economically and reliably deliver payloads for the Department of Defense?”

    While this was in character for the man regarded in the spaceflight community as Senator Proxmire, Enemy of Progress, it is important to recall that his ire toward spaceflight was not all-encompassing--and indeed, that contributed to his grievances. In 1983, Promire had been persuaded by Carl Sagan to support, or at least not oppose, the Search for Extraterrestrial Intelligence. In the years since then, he had warmed to at least the unmanned part of the American space program, particularly those parts relating to Earth observation. While most writers at the time dismissed Proxmire’s attacks as cynical self-promotion, of the same kind as that which Proxmire’s hated predecessor, Joe McCarthy, employed against alleged Communists, there does appear to have been an element of genuine anger that one of NASA’s “worthwhile” missions had been lost by a failure of a vehicle in the manned spaceflight program. He spent a great deal of time asking Stonecipher whether STC had taken special precautions to ensure a successful flight for Magellan. Stonecipher, for his part, answered that every Lifter launch was taken very seriously by STC, but that every flight carried some risk. “We’re aiming for airliner-like operation. But even the 747 I took to get here from Los Angeles does not have a perfect safety record.”

    Moving on from STC, Proxmire next summoned the Director of the Launch Contracts Office at NASA to explain how much oversight NASA had over STC, and why NASA had not called attention to the culture of complacency noted by the Magellan Review Board. The Launch Contracts Office, established in 1983, awarded launch contracts to STC and to Martin-Marietta (beginning in 1985 with the Complementary Expendable Launch Vehicle (CELV) block-buy). It was also the main office through which NASA interacted with STC for Lifter operations, though a separate office, the Crewed Spacecraft Launch Operations Office, coordinated Shuttle operations with STC until separation from the S-IVC, after which Johnson Space Center took over directly. Proxmire asked the Director, Timothy Cizadlo, why NASA had chosen to stick to Lifter even as this culture developed, rather than go with proven expendable launch vehicles like Titan IIIE or Atlas-Centaur, whose pads, still in mothballs, could have theoretically been revived. Cizadlo answered gracefully enough to get a laugh out of Proxmire’s colleagues: “We didn’t want to fleece the taxpayers by buying the same service for a higher price.” Proxmire, undeterred, continued by calling into question NASA’s ability to oversee even its unmanned spacecraft. “Perhaps NOAA would do a better job studying the atmospheres of other planets,” he mused.

    As the hearing continued, Proxmire called into question the efficacy of the Space Lifter program in satisfying the US government’s space access needs, asking whether the program was really a great improvement over earlier, expendable rockets. He asked further whether the Launch Contracting Office was under pressure to favor STC over other programs, due to that company’s closer relations to NASA’s manned spaceflight program. On this point, Cizadlo was adamant: "One failure does not obscure the fact that the Lifter has been a success. Launch costs are down. Private investment in space is up. We've turned the investment of NASA into an entire new sector of the American economy. I challenge anyone in this room to tell me that Atlas or Titan could have done that." Hearing no objection, and seizing the moment, he went on: “My office has done business with STC since that company’s foundation, and during that time, and even before that, while Lifter was under NASA’s direct jurisdiction, the program’s safety record and costs were equal to or better than those of the expendable boosters it’s replaced. Better than Atlas or Titan could have, Lifter has enabled NASA to achieve its goals in space--and when I say that, I’m not just talking about launching any given payload, but about the objectives listed in the National Aeronautics and Space Act--the preservation of American leadership in applied space technologies. Launching cheaply is not the end goal, though it is an important part of our selection process. My job, and the job of everyone at LCO, at NASA, and the job for which we pay STC, is to expand American companies’ access to space. In my judgement, even with this recent incident, STC has done an admirable job.”

    Ultimately, Proxmire’s hearings did not have a great impact on the relationship of NASA and STC, or on STC’s place as the primary launch provider for US government satellite services. While Ariane won more launch contracts in the years after Magellan than it did before, as satellite operators made sure to keep relations with Arianespace open in the event of another failure, STC would ultimately return the Space Transportation System to flight, and reclaim its share of the commercial satellite market. Contemporary political commentators wrote the hearings off as one last windmill at which Proxmire wanted to tilt before his retirement, an assessment that Proxmire himself strengthened when, in January of 1989, he awarded the last Golden Fleece of his career to the Space Transportation Corporation and NASA’s Launch Contracting Office (for his part, STC Chairman Stonecipher is said to have hung that Golden Fleece on the wall in his home office, remarking “it’s a shame they didn’t call Lifter ‘Argo’”). However, Cizadlo’s defense of the accomplishments of the Space Transportation System reflected a growing sentiment at NASA that the agency’s role in opening the High Frontier was that of a trailblazer.
     
    Chapter 12: Lofted
  • “We recommend that: The NASA Modified Launch Services Agreement be extended, as space operations grow, to include interorbit transport services, base camp support services, and other services as appropriate.”
    --Pioneering the Space Frontier, 1986
    Chapter 12: Lofted

    Most of a rocket’s weight at take-off is propellant, and Constitution was no exception. As she rose from the launch pad, she burned tons of propellant per second. Bound as she was by the same Newtonian physics that governed all cosmically slow bodies, her acceleration crept up as she left mass behind in Earth’s atmosphere. The stack that had seemed to crawl off the launch pad was, by the time Constitution released Endeavour and her S-IVC, pushing up into space at 5 Gs.

    All of a sudden, that acceleration disappeared. Subtly, inaudibly,
    Endeavour’s structural members flexed in response to the sudden release of load, aluminum and titanium members shifting like springs. In the cockpit, Fred Haise and Dick Truly could sense none of that; only the accelerometers on their dashboards and their own sudden weightlessness confirmed the shout of “MECO” that came over the radio from Constitution.

    Then the S-IVC’s engine lit, a feeble successor to
    Constitution’s five monstrous motors. The Shuttle and its long upper stage began to accelerate in turn, starting at only a third of a gravity. The feeling of weight was not confined to the Orbiter--as Constitution caught some of the gas the J-2S-2 scattered, her crew too felt a shred of the engine’s force.

    “Almost feels like the Moon,” observed John Young over the comm loop.

    “I don’t know about the Moon, but if you’re done catching our wake, we’ll see you on the other side of the sky,” answered Haise wryly.

    One third of a G is not a spectacular acceleration. Had the Lifter not already given her a large vertical velocity,
    Endeavour would in fact have begun falling back to Earth. Her trajectory was heavily lofted, allowing the S-IVC to burn toward the horizon, to give her a downrange velocity while she ate away at the altitude with which the Lifter had invested her. But with time, it adds up. Slowly but steadily, the propellant burnt off and the accelerometers picked up. Endeavour was on her own path, gathering velocity and altitude by the second, one which would take her far away from the Lifter Constitution, far beyond any Lifter’s capabilities. Men had flown here before, but Endeavour brought a new capability, and would allow them to take small steps and giant leaps of which the first astronauts could only dream.


    As the US Army’s frontier forts had once paved the way for settlement of the American West, as the expansion of military aviation paved the way for the explosion of civil jet travel after the Second World War, so NASA, by creating the Lifter, had expanded the market for satellites and other payloads in Earth Orbit--a market that was swiftly filled by satellite television, advanced communications satellites, and, lately, commercial interest in Spacelab and new earth observation systems. By 1989, Martin-Marietta’s ambitions in the field of space launch had become an open secret, and communications giant Motorola was in the planning stages for a new constellation of low-orbiting satellites. At NASA, the sentiment prevailed that the job in Low Earth Orbit was nearing completion, and that it was time to look further outward. As the National Commission on Space had written in 1986, in its report Pioneering the Space Frontier, the purpose of the American civil space program was to “lead the exploration and development of the space frontier, advancing science, technology, and enterprise, and building institutions and systems that make accessible vast new resources and support human settlements beyond Earth orbit, from the highlands of the Moon to the plains of Mars.”

    The election of George H. W. Bush and his inauguration in 1989 provided a fertile ground for that new direction. Like Spiro Agnew before him, Bush, as Vice President, had been tasked with overseeing aspects of the American civil space program in President Reagan’s place, reporting directly to Reagan when needed. In 1988, after the loss of Magellan and during the consequent stand-down of the Space Transportation System, Bush met with Administrator James Beggs to discuss the Lifter’s return-to-flight and the Complementary Expendable Launch Vehicle program’s performance in the meantime. During this time, Beggs and Bush also discussed the recommendations of the National Commission on Space and how they could be implemented in the future, after Lifter’s return-to-flight. While under no illusion that he would retain his post as Administrator in 1989 (he already planned to submit the customary resignation to the new President), Administrator Beggs demonstrated an admirable devotion to duty in his last months, trying to make his successor’s job and that of the incoming President as easy as possible.

    Authorized by Congressional mandate in 1984, the NCS reflected the growing prominence of planetary exploration and even settlement at NASA. Since the Case for Mars conferences in the 1970s, themselves spurred by the success of the Viking program, the Red Planet, so long viewed as a barren, cratered wasteland, had gotten massively better PR, with ample discussion of the planet’s vast deposits of ice, its tenuous but useful atmosphere, and the tantalizing possibility of finding microscopic alien life. As Werner von Braun’s work with Walt Disney and Willy Ley’s articles in Collier’s had done thirty years earlier, the conferences, and the mass-media articles they generated, had built up some institutional momentum for human exploration of Mars. When the NCS published Pioneering the Space Frontier in 1986, it unambiguously named a human mission to Mars at some undefined future date the nominal goal for America’s civil space program. To accomplish this goal, the NCS called for the development of new, lower-cost launch technology (and an expansion of NASA’s commercial launch contracts beyond Low Earth Orbit), advanced interplanetary propulsion technology, nuclear reactors for in-space power, closed-loop life support systems, and a fully-reusable interorbital tug. It was these recommendations that would inform NASA’s plans for space exploration in the 1990s.

    Such ambitious plans, while promising a path forward for NASA to use Lifter to access the Moon and beyond, would have to percolate at the highest levels. In the near term, the larger concern was seeing Lifter on a safe return to flight. Though the initial causes of the STS-116 ignition failure were traced within months, the quality control and procedural changes necessary to address the deeper roots of the issue lasted longer. The time was also needed for the final tests and qualification of the Dual Engine Upper Stage, which added a second J-2S-2 for reduced gravity losses, increased payload, and better performance in abort scenarios. One of the key recommendations of the Magellan Review Board was for any critical missions in the future to make use of the S-IV-D Dual Engine Upper Stage. Even if the extra capacity to orbit wasn’t required, the increased system redundancy in the only part of the STS which was not capable of post-flight inspection and requalification was worth the price. STC’s contract office quickly saw many of its customers making the same decision, seeking to switch existing contracts onto the Space Lifter with DEUS. Even from the beginning, STC had expressed some internal concerns about the increased overhead and process complexity of two stage production lines. The new thrust structure would necessarily contain very few common parts, thanks to changes in feed lines, control runs, stage attitude control, as well as the simple mechanical attachment of the engines. With more and more interest in the S-IV-D and concerns about the increased scrutiny which would be required on future SEUS launches, STC made the bold announcement that they would voluntarily commit to retire the S-IVC entirely, switching existing bookings onto the S-IV-D at cost. It was decision driven not just by customer and public relations: shrewd studies had shown with the increased rates of requests for DEUS launches, much of the cost increases caused by the extra engine were matched by retaining a single common stage for all launches. The date for Space Lifter’s return to flight would be delayed until S-IVD was ready, but the time would allow a clean transition of McDonnell’s production operations to the new stage design.

    The ripples from the loss of Magellan were not confined solely to the launch vehicle. The probe’s destruction before reaching orbit had been an inauspicious start to the Mariner Mark II program. Though the spacecraft itself had not been to blame, or even officially part of the program, Magellan was supposed to prove the concept of reusing standardized spacecraft parts to reduce overall mission costs, allowing NASA to launch more spacecraft to more destinations without a radical increase in its budget. Its loss set the program back greatly and left Principal Investigators at universities and laboratories across the US scrambling to preserve their chosen programs.

    At the time of Magellan ’s loss, the Mariner Mark II program had converged on a standardized spacecraft bus design, using elements derived from Voyager and Galileo hardware, together with gyroscopes derived from those used on the latest long-lifetime communications satellites. No fewer than three missions had been planned to use the Mariner Mark II chassis--the Comet Rendezvous/Asteroid Flyby mission, the Saturn Orbiter/Titan Probe, and a Neptune Orbiter and Probe. Other missions also called for using the Mariner Mark II design, but were less well-defined and had not begun development. In other words, Mariner Mark II represented NASA’s entire outer-solar-system exploration plans for the next twenty years or more. The Jet Propulsion Laboratory’s scientists and their colleagues elsewhere in the country had staked a lot on the program, and came together to ensure that the program persisted through the doldrums of the Magellan investigation, in preparation for Lifter’s eventual return-to-flight.

    As a new Administration came to power in Washington, all the agency’s existing programs came up for review to determine how well they fit into the overall vision, and whether their budgets could be sustained in the coming decade. Though Magellan had never completed her mission, the defenders of the Mariner Mark II program could point to the craft’s well-documented cost savings during construction to defend their program’s claim to similarly reduce costs through the use of standardized components. Magellan had cost far less to construct than Galileo, after all, and advocates for the various Mariner Mark II missions could each point to that success when projecting costs and budget overruns for their projects. With the new emphasis on bold exploration and trailblazing at NASA with the rise of the Space Exploration Initiative, the case for a bold new fleet of planetary probes was well-received at the agency’s headquarters and, when it came to their attention, at the National Space Council.

    It helped the program’s case that almost every Mariner Mark II mission had significant European investment, making their cancellation (and subsequent alienation of America’s allies) less attractive to congressmen hungry for their slice of the Peace Dividend (though, as the International Solar Polar Mission had shown just a few years earlier, that approach was not foolproof). The Saturn Orbiter/Titan Probe mission, for example, had begun life in 1982 as a European Science Foundation study into possible joint missions with the Americans, before being adopted by NASA (which had been looking into Saturn missions since the 1970s) as a primary science objective in 1983. The Neptune Orbiter shared a lot of the SO/TP instruments, and in the 1980s was essentially an appendage to that program. The Comet Rendezvous/Asteroid Flyby probe included a number of European instruments, many of them spares from the 1986 Halley Armada, and a set of European-designed penetrator-landers. One by one, the Mariner Mark II programs found their way into NASA’s budget authorizations, and began to take physical shape.

    In the meantime, NASA was looking to polish its image as the Magellan incident report’s conclusions were taken to heart. During the initial months after Magellan ’s failure, the press had been filled with stories criticizing NASA, and for many unengaged by spaceflight it was the first time they had thought heavily of NASA in almost a decade. With the entire Lifter and Shuttle fleet stood down, NASA was taking the time to give each vehicle an intensive inspection and overhaul, but even so there were more vehicles than NASA had inspection bays. NASA’s public affairs office decided to combine the two facts to take advantage of the interest, and refocus it more positively. Shortly after the Magellan Review Board reported, and with the STS on the road to return to flight, NASA announced that the STS fleet would be making appearances at a variety of airshows during the summer 1988 series. The Lifters were capable of ferrying themselves to any runway capable of handling a 747, while the Shuttles were carried routinely on the backs of specially modified 747s. However, except for a few publicity events shortly after the debut of the system, these capacities had only been used to ferry Lifters and Shuttles back and forth across the Gulf Coast and the Southwest, swapping between Vandenberg and Florida or returning for inspections. By the end of the year, every major airshow in the United States had been visited by a Lifter and Shuttle. Plans were even considered to fly the Lifter internationally, carefully working its way north and east across the Atlantic to make an appearance at the Farnborough Air Show. Ultimately, the logistics and time required meant that only the Space Shuttle Destiny (which was light enough its 747 carrier could still make the trans-Atlantic trip uninterrupted) was able to visit--once again, the Shuttle would go where Lifter could not follow. The Space Shuttle and Space Lifter were stars of the 1988 air show circuit, resulting in endless home videos and Polaroid images of Lifters making low flyovers or press footage of crowds circulating around grounded spacecraft.

    While NASA’s image was being rebuilt, however, concerns floated around various space agencies about the length of the stand down. Shuttle’s delays in launches were fortunately not critical: Discovery had carried the Long Duration Exposure Facility back from its sixth orbital stint as part of a satellite deployment mission on STS-112 in February of 1988. Spacelab’s orbital status was more of a concern, as it had only sufficient propellant aboard for eighteen months of independent orbital stabilization. Fortunately, the Review Board’s verdict seemed to indicate that the Shuttle should be flying again well before the deadline, and the station’s man-tended design meant it was robust enough to last almost a year between visits. Nevertheless, with no way to actively address any developing situations, many engineers in Houston sweated long hours over any signs of potentially debilitating issues aboard the platform. The USAF had already planned to delay major servicing of the LUCID spy satellites until the DEUS could enhance payload to their eccentric orbits, so the largest delay was to NASA’s own Hubble Space Telescope. After more than a decade in incubation, the telescope was finally scheduled for launch in late 1988, and the delay directly impacted the telescope’s launch schedule. More than one program manager within Hubble breathed a sigh of relief that their delays had prevented them from being assigned a slot nearer STS-116, and the flagship observatory was specifically cited in the Magellan Report as an example of a payload which should receive the additional redundancy of DEUS going forward even though its mass didn’t require it.

    Waiting with Hubble for a launch assignment after the return to flight were more than a dozen large satellites, ranging from military signals intelligence to commercial satellite platforms. The operators of those under three tons were able to consider arranging flights with ESA’s Ariane, though manufacturing delays on the little-flown vehicle left it unable to rapidly meet the spike of demand. However, for those over 4 tons, which were beginning to approach half of the global commercial satellite manifest, there was only one alternative to waiting out the Lifter’s stand-down: Titan. Though the CELV contract called for Titan to be ready for a launch on six months notice, in fact activating the Titan launch site at Cape Canaveral alone took more than eight, by which time the issues with SEUS had been exposed, the decision to switch all flights to DEUS made, and dates for the return of the Lifter were being discussed. Still, with additional concerns about the potential for further delays in the new stage’s introduction circulating, the first launch of Titan in more than three years went ahead. On October 15, 1988, a Titan 3D roared off the pad at LC-41, carrying a classified military payload to orbit. Two more would fly in December and January to relieve national defense backlogs during the stand down, but the major development came from joint lobbying from Martin-Marietta and a broad group of satellite builders to offer some of the remaining 27 stockpiled Titans at launch cost for commercial customers who had booked Space Lifter flights during the stand-down. For these operators, the sight of launchers capable of carrying their payloads flying while they watched loan payments and stock prices fluctuate was frustrating, as there had been a common impression that STC was, in some sense, backed by the full faith and credit of NASA and the USAF. With that confidence shaken, many were eager for any alternative, and the USAF’s reluctance to release Titans at any price lead to them being seen as a dog in the manger. For the USAF’s part, there were concerns that releasing some or all of the Titan stockpile during the current stand-down could set a precedent for future contingencies, and deplete a reserve which was now seen as having proved its worth.

    While Martin played the role of the business which wanted to offer a product but was restrained by the USAF, their real goals were more complex. While they could use the extra income which came from each launch of a Titan from the stockpile to help fund their Trans-Pacific Launch Industries venture with Mitsubishi, they were just as unwilling to actively antagonize the Department of Defense, and they were careful to always leave satellite builders the ones most loudly calling for the release of Titans. Instead, their complaints about restrictions on commercial sales from the Titan stockpiles were an excuse to rub the industry’s nose in STC’s failure, and drive home the benefits of a Titan-class alternative to augment and (if necessary) substitute for Space Lifter. After all, TPLI’s own new launcher was designed to address just that segment, and the demands now laid further groundwork for sales of its services later.

    Among public relations outreach and launch schedule jockeying on the ground, STC finally made major steps towards Lifter’s return to flight in the fall. The first Dual-Engine Upper Stage, SIV-D-T, was hot fired at Stennis test site on October 15, 1988, marking a critical step for Lifter to return to the skies. In spite of the pressure placed on the tests, or more accurately because of them, the DEUS test program was cautious and incremental, seeking to ensure that the new thrust structure and the systems for igniting and controlling the twin engines would be more reliable than their flight-proven single-engine equivalents. As test engineers rang in the new year, the earliest expected date for the Lifter’s return to service slipped from February 1989 into March. The test program’s delays were frustrating to those depending on Space Lifter for their rides to orbit, but NASA was determined that the lax safety culture which had contributed to Magellan’s loss would not be allowed to reemerge. The S-IV-D would not debut until it was fully qualified, even as the stand down stretched closer and closer to a full year. While the Lifter had been off the flight line, though, decisions were being discussed which would shape the future of the space program.
     
    Chapter 13: Reentry
  • “Anything beats an expensive stack of paper.”

    Chapter 13: Re-Entry

    In the face of that coming hypersonic storm, the feeble impulse of the peroxide thrusters would be of no use, and the muscle power of the human pilots would not suffice to move the mammoth control surfaces on the Lifter’s trailing edge. Here, too, the computer would exert its will upon the ship, coordinating a much faster, wilder dance of hydraulic pumps and motors, deflecting air around the ship to guide it down to the regime where the human mind could again respond quickly enough to make a difference.

    In truth, the phrase “edge of space” is not just a misnomer but a nonsense. The atmosphere does not end, but gradually gets thinner and thinner, until the very faintest wisps of Earth’s atmosphere merge with the thin stream of gas constantly shed by the Sun. The drag force it exerts on a spacecraft, then, is never truly absent, but only stronger and weaker depending on one’s location and velocity.

    Slowly, imperceptibly at first but with ever greater intensity, that force grew as
    Constitution plunged back toward Earth, her broad, flat belly forward, shielding the crew cabin and the engines from the heat of reentry. As she fell, the air beneath her couldn’t get out of her way fast enough, and like the piston in a diesel cylinder hundreds of kilometers long, she rammed the air into a smaller, hotter volume. Hypersonic shock waves formed around her wings and nose, stagnating the local air flow and generating even hotter temperatures.

    Unlike the Apollo and Gemini crews, or their compatriots aboard
    Endeavour, Young and Crippen were only aware of their ship’s assault upon the atmosphere peripherally, through skin temperature gages on their control panels. Constitution was not moving nearly fast enough to heat the air to incandescence, much less to ionize it into a plasma--where earlier astronauts had blazed a glowing trail through the sky, their fall back to earth was understated, calm. Ground tracking cameras had no trouble watching Constitution as she descended back through the atmosphere.

    In the thickening atmosphere,
    Constitution transitioned from a spacecraft to an aircraft. Her ailerons and rudders once again dug into the ever more substantial airflow, exerting immense forces and bending moments on the great ship. But Constitution came from good stock--her ancestor, the Saturn V S-IC, had been built with large structural margins by men more suited to building locomotives than tight-margin missiles. She took the loads and ploughed ever deeper into the atmosphere, through aerodynamic forces that would have already shredded a lesser rocket…

    In the final years of the seventies, the debut test flights of the Space Transportation System had occurred amid major questions about the program: Could a reusable booster really be built and flown with the aggressive semi-retropropulsive, semi-aerodynamic entry and return profile? Could such a booster be effectively reused between flights? How many flights would really be feasible between major overhauls? Would they have sufficiently long lifespans to enable their higher initial costs to be spread enough to beat out the costs of contemporary launchers? Could they turn around fast enough to meet the aggressive flight schedules sold by NASA to Congress, the American public, and institutional and commercial customers? In a little more than a decade, more than a hundred Lifter and Shuttle flights had conclusively demonstrated that the answer to every one of these questions was yes. The Lifter was the vehicle of choice for NASA’s orbital manned spaceflight, for US military reconnaissance, and for commercial payloads. While other launchers like Ariane scrambled for mere tens of payloads, bolstered mainly by European institutional support, Lifter was launching nearly that many commercial communications satellites every year, massing more and carrying more capability than customers could have found on any other system. The USAF had even used Lifter’s massive payload and the Shuttle’s orbital capabilities to demonstrate value for highly classified manned missions to rendezvous with their latest spy satellites in polar orbit. The dreams of Blue Gemini, the Dorian/MOL, and the Dynasoar had come true in the form of the STS-101’s first flight of an all-military crew to space to offer manned assistance--if only in systems maintenance--to orbital reconnaissance.

    However, by May 1989, world events offered new questions as NASA and STC moved laboriously to Lifter’s Return to Flight. In the near yearlong absence of Lifter and Shuttle, new questions had been raised. The Space Transportation System had changed spaceflight and in some ways the world, but what role would it find in its second decade in the world it had created? What would be the effects of Magellan’s loss on STS-116 on the shape of policy for manned and unmanned spaceflight? What did Lifter’s first major failure in more than a hundred launches mean for the next generation of space launch systems, both in the US and abroad? Whatever the answers to these questions, though, one thing was sure: the Space Transportation System was and would remain the keystone for Western access to space. While its supremacy might be challenged by new competition from other Western vehicles or by potential access to the Soviet Groza system, that would only come into play in the long term. Thus, while the winds of change saw thousands of engineers, program managers, lobbyists, and politicians debate the future of spaceflight around the world, thousands more had to fight through the winds to focus on returning the Lifter to flight with its new dual-engine upper stage.

    The groundwork for the return-to-flight with STS-117 had been laid over the development of the Magellan Review Board’s findings, but the final steps came in the form of the qualification firings of the S-IVD Dual Engine Upper Stage vehicle. After the single failure to light the engine on STS-116 had sent the Magellan probe tumbling to its doom, NASA and STC had gone to the unrequested step of transitioning all future Lifter missions to the more redundant, higher-capacity DEUS. Even for payloads where the S-IVD’s enhanced performance and theoretical improved safety were not specifically required, STC made the decision to switch. Doing so was a critical step to rebuilding their reputation with commercial launch customers, but also simplified production, meaning STC would avoid having duplicated lines for two stages. As Lifter’s flight rate had risen, the question of having two such lines had become more critical: throughput was high enough to depend on repeated production operations and leverage economies of scale, tooling, and expertise, but still low if this production was to be split across two stages with nearly entirely distinct thrust structures, pressurization schemes, and other interfaces. However, it meant that the test program for the DEUS directly paced the return-to-flight for the entire program.

    In spite of this, the S-IVD qualification program was extensive, but it was compressed by test engineers working in shifts nearly around the clock to get the initial S-IVD-T qualification stage in and out of various test cells at NASA’s Stennis test site. As results came in while the stage was poked and prodded, rattled and shaken, and finally fired over and over, McDonnell engineers back at Huntington Beach, California worked evenings, nights, and weekends to process it. During the qualification of the integrated stage’s ignition transients and cross-comparison of data with the extensive firing of each of S-IVD-T’s engines before installation, the manager of the engineering team responsible for the Augmented Spark Igniter redesign, which was an area of particular focus, purchased for his team T-shirts bearing the team member’s names and the phrase, “No Sleep ‘Til Orbit”. However, even as S-IVD-T was put through its paces, the first three production S-IVD stages (D-001 through D-003) were on the production stands, as Huntington Beach continued its proven pattern of building stages in three-unit lots. At least for the moment, the practice of hot-firing completed stages on the way to launch was resumed, after having been deleted for schedule and cost control purposes. Before 1988 ended, the S-IVD-001 stage, earmarked for the STS-117 return-to-flight mission, joined S-IVD-T at Stennis for its qualification firings with 002 and 003 not far behind.

    The qualification program went smoothly, but there was only so far that engineers could push themselves while remaining confident in their tests, their data, and their analysis. As production and testing procedures were overhauled and the conformance of S-IVD-T and S-IVD-001 were verified, February 1989 melted away. The booster for STS-117, the freshly-overhauled Constitution was already stacked and waiting in the VAB when the first live DEUS was delivered to the Cape on February 23rd. By the time the stage was re-inspected after transit, and final integration preparation was carried out, the launch date had slipped into March. Finally, however, STS-117 roared into the Florida sky on the long-anticipated return to flight on March 14th, 1989. Flight controllers were laser-focused on their data during the count as elevated upper-level winds which had plagued the previous day’s launch attempt threatened to once again violate launch constraints. The winds settled within tolerable limits shortly before launch, and the actual staging and the first ignition of a Dual-Engine Upper Stage in space were picture perfect. The successful deployment of a pair of commercial communications satellites, whose owners had received a major discount from STC to accept the STS-117 launch slot, brought the return-to-flight to a new phase.

    With STS-117 down, the problem was to ramp launch frequency back to the levels which had become typical prior to STS-116, with launches routinely occurring twice in the same month. More rapid turnaround from KSC’s twin LC-39 pads was possible, but unnecessary as the flight rate was able to meet the available payloads, particularly with the double-manifesting of communications satellites. However, with Lifter out of service just weeks shy of a year, there were literally dozens of payloads which were either due for launch in 1989, or which had been scheduled in 1988 and had slipped with the STS-116 failure. The build up of the launch cadence started slow: the stacking of STS-118, with the Space Shuttle Discovery and Lifter Liberty, didn’t begin until STS-117 was safely flown. The mission followed in its turn from LC-39B on April 27th, with Discovery’s crew headed to Spacelab to ferry critical supplies and carry out overdue maintenance on the orbital outpost after over a year untended. However, by the time Libertyflew, STS-119 and Independence were already being prepared with another pair of communications satellites. It was less than three weeks later that Independence followed her younger sisters, and STS-120 on May 20th confirmed that STC was back on pace to meet all its obligations. In fact, to catch up on backlogged flights, Kennedy Space Center was to see no fewer than seventeen Lifter launches in 1989, with another three from Vandenberg including Resolution on a LUCID servicing mission using the new DEUS performance. Fresh off the failure of STS-116 and the critique of people like William Proxmire, Lifter had showed its competitors what they would have to match by breaking its own prior flight-per-year record.

    With the Space Lifter back in action and STC and their teams working above and beyond to clear the flight backlog and return to a regular launch cadence, NASA had finally worked through enough turbulence to look beyond the day-to-day operations and into future planning. However, the election of George H. W. Bush as the 41st President of the United States had brought massive changes to the way that the American civil space program was run. In order to better coordinate civil, military, and commercial space efforts in the US, Congress had authorized the creation of a National Space Council, answerable directly to the Vice President, and through him the President, designed to “set ambitious goals and maintain American preeminence in space, while further integrating the High Frontier into the American economy,” in response to the embarrassing loss of Magellan and the rising Soviet success of Mir. The activities of American private and semi-private space firms, including Space Transportation Corporation, Geostar, PanAmSat, and other new satellite communications companies, were now also distinct enough from NASA and other US government functions to merit oversight and coordination beyond a mere office at NASA headquarters. It was hoped the NSC could recommend to the President the most effective ways to promote continued American success in space on all fronts, transcending the bureaucratic limits of the civil, military, and commercial sectors.

    Bush’s surprising choice for head of the NSC was Mark Albrecht, who had been a Senior Research Analyst working for the CIA on the Strategic Defense Initiative, and who had written the Republican Party’s 1988 platform on defense. Though he had ample experience with the policies and management of the USAF’s space policies, he had not previously worked with NASA, raising some concern as to whether he could actually tackle the challenge of giving the agency a new direction.

    President Bush’s nominee for the new administrator of NASA also raised eyebrows. On Albrecht’s recommendation (for he had worked with him on the SDI), Bush nominated a little-known middle-manager at TRW named Dan Goldin, who had distinguished himself by applying advanced microelectronics technology to satellite design, and for pitching a cheaper design for NASA’s Earth Observation System satellites, emphasizing modularity and shared components with commercial satellite busses and the less-classified Department of Defense intelligence satellites. Though competent, he was essentially a “nobody” in Washington--it was, in fact, not until his confirmation hearings that his registration with the Democratic Party became public knowledge (somewhat to Bush’s annoyance, though, as Dan Quayle noted at the time, “he certainly didn’t have any trouble getting confirmed” in the Democrat-held House or Senate).

    The third individual who formed the “Space Troika” of the Bush Administration was Vice President Dan Quayle. Like Bush, Agnew, and Johnson before him, Vice President Quayle was expected to handle the NSC’s day-to-day operation and make recommendations to President Bush. It was Quayle who first proposed that Bush should make a major space policy announcement on July 20, 1989, the twentieth anniversary of the landing of Apollo 11 on the Moon. Bush, eager to counter criticisms of his “lack of vision” and possibly in an effort to step out of Ronald Reagan’s immense shadow, readily agreed. From April to July, the National Space Council would work with NASA and representatives from STC and, to a lesser extent, other American aerospace firms to determine the best way forward for America’s civil space program.

    The one feature that most united Goldin, Albrecht, and Quayle was a consensus that they had to operate within realistic budgetary restrictions. Conscious of Agnew’s failure to pitch Tom Paine’s vision of a mission to Mars by 1986, Quayle wrote in a memo in late April of 1989 that “the Democrats who control congress are not LBJ. The man in Moscow is not Khrushchev. President Bush doesn’t have a dead predecessor to avenge. Those are our constraints.” In this light, the nominations of Goldin and Albrecht, both innovative, fat-trimming managers with a history of effective cost and scope control, becomes less surprising. With their constraints in mind, and after a series of meetings with upper management at NASA and at STC, and with Norm Augustine at Martin Marietta, the National Space Council (NSC) turned to the recommendations of the National Commission on Space (NCS) and worked to determine which technologies were on the critical path to Mars, what infrastructure would be needed to prove them, and which of those technologies really needed up-front government support.

    To this end, the NSC took the NCS’s list of enabling technologies and infrastructures for crewed missions to Mars and began whittling down those deemed less central to NASA’s mission. Based on discussions with executives at TPLI and Martin-Marietta, they concluded that the private sector was already developing lower-cost launch vehicles, making a government-funded one redundant, at best. The assumed near-term availability of such vehicles also reduced the urgency of developing advanced in-space propulsion technologies--if the cost per-kilogram to LEO fell far enough, the importance of reducing initial mass in LEO fell with it. This left as the main technological goals for a human mission to Mars the development of in-space nuclear power sources, a reusable interorbital tug, and a closed-loop, long-term life-support system. While each of these three technologies would require a large research and development effort, none of them in themselves could satisfy the primary goal of President Bush’s planned new direction in space--to demonstrate American preeminence. The American public, and the public overseas, would not see a qualitative difference in the scope of American activities in space if only these technologies were developed or even flight-tested. Satisfying the President’s desire to demonstrate American preeminence would require a near-term goal that could easily be conveyed to the public. Following this train of thought, Goldin and Albrecht summoned a commission of engineers and scientists from the major NASA centers and asked them to design reference missions for a human lunar return by the year 2000, with the caveat that as much of the new technology and infrastructure developed for such a mission be applicable to a Mars mission some time in the twenty-first century. Even as they worked, President Bush made his great speech at the National Air and Space Museum, flanked by Neil Armstrong, Buzz Aldrin, and Michael Collins, the heroes of Apollo 11:

    “In 1961 it took a crisis—the space race—to speed things up. Today we don’t have a crisis; we have an opportunity. To seize this opportunity, I’m not proposing a 10-year plan like Apollo; I’m proposing a long-range, continuing commitment. First, for the coming decade, for the 1990s: A new cislunar infrastructure and a return to the Moon, with a sustainable, reusable architecture, building upon our successes with the Space Lifter for the past decade. Next, for the new century, to open the Moon to American industry as Earth Orbit has been opened, to tap the physical resources of the High Frontier. And then, journeys--not just one, but many--beyond the Moon, to the other planets, leveraging again the skills we built on and around the Moon, beginning with a Manned Mission to Mars.”

    The hidden genius of Bush’s speech was that it recognized Mars and the other planets as the goal for which his new program aimed, but it left the actual planning for Mars missions until some undetermined point after the technology was refined in cislunar space. Though this approach received some criticism among some sectors of the space advocate community (and from Martin Marietta, whose Vice President for Space Operations would go on to propose in 1998 that all that was really needed for Mars missions was a slight modification of existing launch vehicles and LEO systems), in practice it took a great deal of pressure off NASA’s engineers and managers, as they did not need to design Mars missions to fit an, at best, modestly-increased budget. Indeed, a preserved memorandum from Administrator Goldin to Vice President Quayle indicates that concerns about controlling overall program costs were already surfacing at NASA and the National Space Council in May of 1989, as Goldin warned Quayle that, since the idea of the program was to design hardware that could be modified for Mars missions later on, it didn’t make all that much difference to the final schedule whether the Mars program begins in 1990 or in 2000. Therefore, the memo continues, NASA should focus on pitching the lunar return program first, as it was easier to secure funding for one part of the program than for both, and because such an approach gave the agency and its partners greater flexibility down the line. Goldin made reference to the “phased development” approach NASA had taken to the Space Transportation System, which had yielded the reusable booster, a reusable orbiter (though without its own significant propulsion), and a space station, which had yielded immense benefits for the agency even without the remaining elements of the STS. The fact that the second phase of that development (the large, integral-propulsion reusable orbiter and reusable space tug) had not yet manifested was noticeably absent from the memo.

    The architecture that emerged in response to President Bush’s call for a Space Exploration Initiative (as the effort came to be known), developed by engineers from Johnson, Marshall, Kennedy, and STC, with consultation from every prime contractor in the American space industry (and quite a few of the secondary contractors), thus centered on operations on the Lunar surface and in Lunar Orbit. The new architecture called for a reusable in-space transport vehicle (the long-delayed Space Tug) providing logistical support to a reusable lunar lander, which could carry either cargo or crew down to the lunar surface from a small orbiting maintenance platform. The reusable Space Tug would, in addition to servicing the lunar lander and lunar orbital platform, deliver satellites to geostationary orbit and inject probes to interplanetary trajectories, providing a cheaper alternative to the Centaur upper stage and amortizing its development cost over more missions. The technologies developed for the Tug and Lander would also have applications for the long-term storage of propellant for Mars or other destinations.

    The proposed program, Option B, was one of three paths forward presented to President Bush in the early autumn of 1989. The other two, Options A and C, called for, respectively, a 20-year ramp-up of space activity in cislunar space and on the Moon culminating in a landing on Mars by 2012, and a lower-intensity program of technology development in cislunar space (essentially, the recommendation of the NCS in 1986). NASA presented President Bush with cost and time estimates for the various milestones of each project, with Option A featuring a lunar landing by 1998 and a permanent base in 2001, for a total price-tag of some $200 billion. Option C was somewhat more nebulous--each component of the program, from a full-time space station in Low Earth Orbit to test out closed-loop life-support technologies to a completed Nuclear Thermal Rocket development program to a new hypersonic flight development program, had its own schedule and cost. What they lacked, in Bush’s eyes, was a concrete end-point at which the United States could declare “Mission Accomplished!”

    Option B, while nominally aiming to develop a system that could be used for Mars missions, did not give cost or schedule estimates past the year 2000. It called for the completion of the interorbital Space Tug by 1996, and for lunar landings by 1998. Though the Lander would be of great utility in building a base, that was left to the next administration. Similarly, though Option B also called for a small, full-time space station to serve as a test-bed for “long-term space habitation technologies,” it did not propose schedules or costs for an interplanetary version of this space station. This greatly reduced the cost estimates that NASA could suggest to the President--compared to Option A’s $200 billion price tag, Option B was estimated at just under $40 billion, spread over 8 years. For that price tag, NASA would have three new vehicles (the Tug, the Lander, and the Space Station), an American flag on the Moon again, and a small suite of new technologies that could indeed be directed toward human Mars missions in following administrations. Furthermore, once the Tug and (possibly) the Lander were spun off into a new contracting organization (as STC had been spun off to operate Lifter), the operational costs would (theoretically) fall off and operations between LEO and the Moon would fall to the private sector, just as operations between Earth and LEO had.

    By early October, Bush had been sold on Option B, and the Space Troika’s challenge had shifted from the comparatively simple task of briefing a sympathetic President to the much more complex challenge of selling a flashy new technology program to Congressmen already salivating over the fruits of 44 years of Containment…
     
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    Chapter 14: Turnaround
  • "We must, indeed, all hang together, or assuredly we shall all hang separately."

    Chapter 14: Turnaround


    Constitution plunged deeper into Earth’s atmosphere, trading height for velocity and then dumping the resultant kinetic energy overboard as heat, leaving a trail of superheated air through Earth’s atmosphere. Her peroxide thrusters were silent now. Instead, the potent chemical was routed into a turbine, the auxiliary power unit, which provided the force that drove her great hydraulic motors. Those motors pushed on the ship’s enormous rudders and ailerons, cutting into the surrounding airflow and pushing the ship back home. By now she was out of the realm of missiles and target drones, back under Mach 6, in the regime where human reflexes and training could once again react to the changes fast enough to matter.

    High above the Atlantic Ocean,
    Constitution, still travelling several times the speed of sound, began her long arc back toward Cape Canaveral. She turned to port, toward the north, passing the storm front that had delayed her launch, returning to clear, calm weather over the western edge of the Sargasso Sea. Even from their high, hurtling perch Young and Crippen could have seen, had they a window facing down, how calm the water was here, and made out some of the brown patches of kelp that dotted this region of the Atlantic. Constitution maintained her broad, banking turn, bleeding off more and more speed as she turned back toward the continental US.

    As she did so, her pilots kept a close watch on her rate-of-descent indicators, noting that the rate climbed with time, for
    Constitution remained, aerodynamically, a brick. She had never been optimized for slow, level flight, but for the job of lifting a payload to the upper fringes of the atmosphere. As her speed dropped, so did the lifting force on her wings, and she acted more and more like the wingless fuel tanks she counted among her ancestors. Unassisted, she would not have managed to return to land, and would have flopped sadly into the Atlantic. This had been obvious to her builders, and they had given her a way to overcome that limitation…

    Most historians agree that the start of the Cold War can be dated to 1947, when President Harry Truman announced the Truman Doctrine, pledging to defend any state threatened by Communist expansionism. This doctrine effectively began the US’s general scheme of “containment,” fencing in the Soviet Union and keeping it far away from the US (those countries already fallen to Communism were left to fend for themselves). From that year until 1991, the US labored to contain its main rival, building up a massive military-industrial complex, developing advanced new weapons and delivery systems, stationing troops across the globe, toppling governments, funding rebels, and projecting soft power through, among other things, the civil space program.

    Because of its role as one of the most visible faces of American Soft Power (some 450 million people had watched Neil Armstrong take his first steps on the Moon, roughly ⅛ of all humans alive at that time), NASA had always counted on consistent, if not always expansive support from both the Executive and Legislative branches of the American federal government. Unfortunately, with the demise of the Soviet Union and the end of the Cold War, the agency found itself looking for a new justification for its major programs, as American congressmen suddenly discovered a passion for fiscal responsibility and made promises of new social programs (or, more often, tax cuts). Even as the President proposed a sweeping new plan to expand the agency's goals back to the moon and beyond, NASA found itself struggling to justify the funding which such endeavors might require. The agency approached its international partners, the European and Japanese space agencies, in an attempt to expand the Space Exploration Initiative from a program of discretionary spending to one of international diplomacy. While the Solar Polar Mission a decade earlier had shown that that did not necessarily make the program bulletproof, it was hoped that offloading some of the development costs to the international partners would reduce costs and make the program more palatable to Congress, while also making the more foreign-policy-minded Senators more hesitant to cut budgets.

    The European Space Agency, drawing on its years of experience operating Spacelab, and its ongoing experience designing the planned Spacelab emergency reentry capsule, the Crew Return Vehicle, was fairly enthusiastic about the opportunity to work with NASA on a return to the Moon. It did not take long for ESA to propose the use of their Spacelab CRV for the lunar program. Though the program’s heritage includes Manned Ariane studies that date back to the mid-1970s, it formally began in 1983 as part of a study into extending the Spacelab space station into a permanent outpost. As the American Space Shuttle did not have the ability to remain docked to Spacelab indefinitely, a new vehicle was required that could remain docked at Spacelab for up to three years at a time, and which could quickly return a sick or injured crewmember to Earth for medical attention.

    Though early designs favored a lifting-body or winged reentry vehicle, whose crossrange would enable landings in either the US or Western Europe on a runway, development cost constraints and mass restrictions on Ariane (whose use as a manned launcher remained a long-term goal in certain circles of the French space agency) led CNES to focus on a headlamp-shaped capsule, very reminiscent of the Soviet Soyuz and Zond designs. With a diameter of 2.8 meters, the capsule would have room for four crewmembers in rather cramped seats. Though the seating was not a serious concern during spacecraft design (as an emergency return capsule, by definition, would only be occupied for a few hours at most), the capsule design did limit the spacecraft’s cross-range, forcing the ESA to investigate landing sites outside of Europe and America in order to guarantee that, in very dire circumstances, crews would not need to wait several orbits before landing. Oceanic landings were ruled out for both reasons of time and budget, so the ESA and the French government sent representatives to almost all large countries over whose airspace Spacelab orbited, including the United States, Australia, Brazil, India, the Soviet Union, and large parts of the former French and British empires in Africa (China, oddly, was not consulted for possible landing coordination, and discussions on the topic would not take place until the late 1990s). Ultimately, renewing its historic partnership with the European space ministries, Australia offered its Woomera Test Range as the main backup landing site for CRV capsules.

    Through the use of more modern manufacturing techniques and lightweight alloys, and the use of a very minimalistic “service module” (essentially a set of retrorockets with explosive separation bolts), the entire spacecraft came in at under 4,500 kilograms (a further 1,000 kilograms was allocated for a maneuvering bus that, launched with the CRV on an Ariane 2 rocket, would guide it to a docking with Spacelab). It was this design that was frozen in 1985 as “Asclepius,” after the Greek god of medicine.

    By 1989, the European CRV was far-enough along that almost every analysis conducted at NASA’s Johnson Space Center found it to be the fastest and most cost-effective path to a lunar return vehicle. While the Space Shuttle was well suited to returning crews from Earth orbit, the higher speeds of lunar entry would subject it to far more heat than it could handle, and the added weight of the Shuttle's cargo bay and winglets would be of minimal use on circumlunar or lunar orbital flights. The European capsule, by contrast, was lighter to begin with, and its simpler shape made uprating its thermal protection system a smaller challenge. Under ESA’s proposal, an enhanced, longer-lifetime, more-durable variant of the Spacelab Asclepius CRV would serve as a crew capsule that would carry the crew to Low Lunar Orbit and back, propelled by a reusable American Lunar Transfer Vehicle. The capsule, with room for 4 astronauts, would separate from the LTV as both spacecraft approached Earth, allowing the LTS to propulsively brake into orbit for reuse. This plan, which European engineers dubbed “Hermes,” achieved a number of goals for both NASA and the ESA--it gave the latter a high-profile contribution to the Initiative, and it saved the former money by making heavy use of a system already in development for Spacelab. The plan, dubbed the "Exploration Crew Return Vehicle" (eCRV) by NASA engineers, was an easy sell to cost-conscious NASA managers, particularly after program managers working on the new Space Habitat program settled on a plan to use the same Hermes system for transits between Spacelab and the new station. Ultimately, many more Hermes than Asclepius capsules would be built, as only the former was planned for actual operational use on either new program. Though the transition from “permanent Spacelab” to SEI would eventually consign Asclepius to that status of a technology development/prototyping program (one prototype was completed, but never meant for flight), the work done on the Block I eCRV massively accelerated the Block II spacecraft’s progress once that program finally received the green light in 1991.

    Though Hermes was a popular choice with NASA’s management, it was controversial at Johnson Space Center and with American aerospace companies, who protested the use of a foreign vehicle over their own concepts. Though JSC was eventually brought on board (Goldin’s argument that foreign cooperation helped ensure there was any Initiative at all found a positive reception among the center’s management), Rockwell International and Grumman Aerospace were particularly vocal, the former having not anticipated serious competition with their own proposals, the latter in particular financial pain with the cancellation of further F-14D Tomcat orders and the uncertain future of the Space Nuclear Thermal Propulsion program on which the company’s space division had pinned its hopes. The latter company’s proposal of a cheap MPEM-derived habitat, which would remain attached to the LTS for its braking burn and rendezvous with a Space Shuttle Orbiter, had never been the front-runner at NASA, but its low development cost had had its share of supporters. Ultimately, though, both companies lacked the clout they once commanded. Poor management decisions had left Grumman without a healthy diversity in its portfolio (forsaking high-speed trains and civil aviation, the company later halfheartedly invested in sewage treatment, alternative energy, canoe building, and truck manufacturing, with decidedly mixed results), and it spent the 1990s refocusing on electronic warfare systems, divesting its once-fantastic manufacturing infrastructure. New York’s senators were unsympathetic to the plight of a company that could not even offer many jobs to Long Island. Rockwell International, for its part, did not complain as loudly, hoping that its Rocketdyne division could still secure contracts in the planned lunar lander and lunar transfer infrastructure programs. Though much larger than Grumman, it too felt the pinch of the Peace Dividend, but it still had more to lose.

    The decision to use the eCRV as the inter-station transfer vehicle marked the last attempt by Grumman Aerospace to be an independent prime contractor on a space vehicle. Prior to the selection, the options considered by NASA included the eCRV, a new space-only vehicle that would combine an MPEM-derived pressurized cabin with a modified communications satellite bus, and a Space Shuttle orbiter (which would restrict inter-station flights to times when a visiting Shuttle was available). The space-only vehicle would be the most mass-efficient method of travelling between the stations, as its thin aluminum shell did not need to have any protection from atmospheric stress. In many respects, the proposal resembled older Grumman attempts to repurpose the Lunar Module for LEO applications. While the company had, in the early 1980s, already begun transitioning into an electronics-focused subcontractor, Grumman Space Systems had not given up hope that the company could continue to produce some kind of space hardware. The Space Exploration Initiative was very warmly received in Bethpage and Calverton, where Grumman executives saw in it very clear applications for the company’s last flagship space technology programs: MPEM and the Space Nuclear Thermal Propulsion project. Alas, the shift of focus away from Mars and toward near-term operations in cislunar space doomed both of these efforts, as the need to validate the eCRV in flight and to conserve funding by down-selecting to the smallest number of new vehicles led Space Habitat’s planners to simply use one of the Block II eCRVs (which would be mounted to the habitat anyway as a semi-permanent lifeboat) as the transfer craft.

    The European Space Agency was also open to cooperation with NASA on the development of the new, full-time Space Habitat, particularly after the agency clarified that the Space Hab was not intended to draw resources away from scientific use of Spacelab (indeed, that it could co-orbit with Spacelab so that routine resupply and crew rotation runs could be performed to each station on one mission). As that Space Habitat took clearer form, however, it became clear that ESA would be the junior partner in that particular vehicle. A decade of Spacelab operations had shown that microgravity was still a trouble spot for long-term space missions. Repeated attempts to mitigate the problem with pharmaceuticals and exercise had shown some improvement, but bone loss and muscle atrophy remained unresolved by the early 1990s (mechanical resistance suits, tested by the Russians on Salyut and Mir, were proposed in the West but had never been test-flown in the American program). As a result, particularly after the success of Wetlab in 1987, American space station planners had come to favor a space station with artificial, tumble-induced “gravity,” which would not only mitigate astronaut health problems but also simplify the design of life-support systems. Since all the experience with artificial gravity was concentrated in the US, it became clear early in the development program for the SEI Space Habitat that NASA, specifically Johnson Space Center and prime contractor McDonnell Douglas, would take the lead in planning the Space Hab.

    For their part, the ESA was willing to collaborate on such a space station, offering an ERNO-built Command and Service Module to serve as a center of communications, thermal control, and power for the station while the United States supplied the S-IVC Wet Workshop and the Docking Module. While some of the proposed components could be repurposed from Spacelab spares and structural test articles, the unique, tumbling operation of the Space Habitat would require some new hardware designs, particularly in the solar arrays, whose ability to track the sun was compromised by the vehicle’s rapid movement. The Space Habitat CSM would ultimately become a collaborative effort between Entwicklungsring Nord and American aerospace giant Boeing, with questionable cost savings, but clear political benefits.

    NASA’s next-largest international partner agency, the Japanese NASDA, did not bring as much space flight experience to the table as Europe did. Primarily concerned with establishing Japanese launch and earth-observation satellite capability, the agency had not paid much attention to human spaceflight or spaceflight beyond geostationary orbit until the late 1980s, when the surging Japanese economy permitted greater investment in such projects. When it finally did invest more, it produced work on-par with the best engineering in the US and Europe, notably the LE-5 and -7 rocket engines, which were by 1991 slated to power the “Sierra” reusable launch vehicle under development by Trans-Pacific Launch Industries. It was through TPLI that NASA sought to involve Japan in the Space Exploration Initiative, by arranging propellant resupply for the Lunar Transfer Vehicle and logistical support for Spacelab and the Space Habitat in exchange for the presence of Japanese astronauts on lunar missions.

    By 1991, “Sierra”’s design had been frozen and work had begun on actual development. The original two-stage reusable design was expanded so that, on geostationary missions, payloads would be pushed into their transfer orbit by a Castor 30 stage, a cheap, expendable solid rocket derived from Thiokol’s Minuteman missile. With the end of the Cold War, Thiokol found its Minuteman production lines underutilized, and so was eager to sell quarter-length derivatives to TPLI. As part of the contract, Thiokol also signed an agreement with Ishikawajima Heavy Industries of Japan to manufacture a limited number of Castor 30s on license, for Japanese government payloads.

    While Sierra’s first stage was a fairly narrowly-defined VTVL rocket stage, the second stage was, upon further analysis of the Low Earth Orbit market, redesigned into a vehicle that blended the capabilities of a dedicated spacecraft and a launch vehicle stage. Unlike airplanes, rockets, even partially-reusable ones, had no clear way to salvage a payload in the event of a loss-of-mission. The loss of Magellan had underlined this shortcoming, leading TPLI to search for a way to provide its customers with a way to ensure that their payload, whatever happened, could at least be brought back for a second launch attempt. The most effective way to provide this capability, Martin-Marietta’s engineers found, was to provide a payload bay, nestled between the second stage’s two propellant tanks. The bay, pressurized during ascent for greater structural integrity, would vent its residual atmosphere out into space before opening a clamshell door, exposing the payload and any attached booster to the vacuum of space. In the event of a first-stage failure, the second stage could separate and recover the payload, returning it safely to Earth. Furthermore, the payload bay could also be occupied with a reusable pressurized cabin, allowing the second stage to provide crew rotation and unmanned logistics to the growing fleet of space stations in Low Earth Orbit.

    Pleased at the potential development of yet another partially-American reusable launch system, this one aiming to be fully reusable and optimized for payloads which were individually undersized for cost-effective launch on the Space Lifter, the NASA Launch Contracting Office signed a Memorandum of Understanding with TPLI. In the document, TPLI committed that they would aim to design their vehicle to meet NASA’s stringent requirements of safety and reliability for institutional launches and potentially even the higher standards for manned flights, and that should this condition be met, NASA's LCO would help work with the rest of the agency and other government organizations like the FAA and USAF to see the Sierra launcher certified to be a competitive bidder for the launch contracts that the office was responsible for negotiating and approving. A particular eye was given to using Sierra for propellant transfer to the Lunar Transfer Vehicle for the SEI. This memorandum was signed in a visit by the office’s Director to TPLI’s office in Boulder in which he met with the heads of the joint venture and senior members of the design team. It was viewed by NASA as a gesture of support for a new, partially-American firm helping further the development of reusable vehicles, without spending a dime of government money that wouldn’t have been spent otherwise--a point on the mind of an Office whose Director had quite recently had to repeatedly defend the Agency’s near-sole-source relationship with STC for launches of all large American payloads.

    Whereas NASA’s agreement with the ESA on Space Habitat and reentry capsule development had been met with fairly muted protests, NASA’s agreement with TPLI (and through them Mitsubishi and NASDA) was decried by STC as a subsidy to foreign interests almost before the ink of Cizadlo's signature was dry. Pointing out that TPLI had yet to even reach Low Earth Orbit, STC officials aggressively lobbied their counterparts at NASA to concentrate on using the Space Lifter, with its long flight history and considerably greater per-launch payload, to support the Space Exploration Initiative and other institutional launches. While an understandable reaction in a purely mercenary sense (it is natural, after all, for a company with a de facto monopoly to attempt to retain that monopoly), this initial panicked reaction annoyed many at NASA, and led senior NASA officials (including Dan Goldin) to double-down on their commitment to the partnership with NASDA and TPLI. At no point did NASA indicate that TPLI would be receiving a monopoly on SEI launches (indeed, the limited payload of the Sierra launch vehicle compared to the Space Lifter made the latter necessary to realize the program’s goals). As such, STC’s attempt to lock TPLI out of even a partial share came off as presumptuous in the extreme. Furthermore, the partnership with NASDA and TPLI held the promise of a true redundant alternative to the Space Lifter, which could operate at a lower cost than the remaining Titan IIIs in the event of a future Space Lifter failure, and whose availability was not at all in doubt (unlike the USAF Titan IIIs, which were assigned to national security payloads first and foremost). The Space Lifter’s year-long stand-down had thrown NASA’s dependence on the launcher into sharp relief, and no one wanted to risk a year-long stand-down during, for example, the fueling campaign for an interplanetary craft on a tight launch window.

    The memorandum, and the controversy surrounding it, was a boon to the joint owners of Trans-Pacific Launch Industries, which had begun to suffer serious financial strain as a result of the long Sierra development process, the bursting of the Japanese asset bubble, and the decline of its missile business. Martin had been relying on Mitsubishi Heavy Industries (and in turn the Japanese government) to supply a great deal of the capital to finish research, development, and testing of the Sierra launch vehicle, which had been planned for a late 1995 or early 1996 introduction to service. The collapse of the Japanese asset price bubble in 1991 severely hampered Mitsubishi’s ability to pick up Martin’s slack, and for a time Trans-Pacific Launch Industries appeared to be on the verge of failure. The resources of the Japanese portion of the partnership were newly constrained just as the company was beginning to to see the expected ramp up in expenses for the preparation of flight test hardware, component testing, and the conversion of launch sites at Tanegashima and Cape Canaveral.

    The memorandum of understanding was a critical sign to commercial launch interests that NASA was as interested as NASDA in seeing the Sierra fly, and its approval was cited as a cause in several high-profile launch contracts TPLI secured in 1993, such as the Iridium and OrbComm low-Earth communications constellations. The down payments on these contracts went almost immediately into the funding of the beginnings of the test programs. The LE-7 was in its final lifespan risk-reduction test stand firings to prove it could reliably serve the role which Martin had demonstrated with the lower performance RL-10 on their Terminal Descent Demonstrator over the past five years. At the same time, with the initial proving tests completed, the first LE-7 production units had already been shipped for integration. Work was underway with the first boilerplate Sierra stage at Mitsubishi’s Nagoya Aerospace Systems Works in Tobishima and Martin’s first Fuji upper stage ahead of the testing of the systems at Mitsubishi’s Tashiro test site and Martin’s old TDD launch site at White Sands Missile Range.

    Even as Mitsubishi began their testing of the Sierra first stage, TPLI launch teams were working out the infrastructure that would support Sierra’s flights to orbit. Three launch sites were identified for the the rocket to serve the Japanese market and the American market for commercial LEO and polar orbits. Japan’s site would consist of a new launch complex constructed at the Tanegashima Space Center which already launched their American-derived N-1, N-2, and H-1 rockets. The American sites would be more cumbersome, as Martin proposed to have TPLI adapt their existing infrastructure at Vandenberg and Canaveral. This would save on development costs, but would require working around the requirements to maintain a mothball capacity to launch Titan III rockets until TPLI could convince the Department of Defense that Sierra could meet their needs to back up Lifter. Thus, for the moment only two cells of the Titan Vertical Integration Building at Cape Canaveral and one of the two Titan launch pads (LC-40) would be converted. A similar Solomonic distribution was happening to the facilities at Vandenberg, with SLC-4 West to be converted for Sierra while for the moment its twin at SLC-4 East would remain on call for Titan. As crews set to work pouring concrete for new launch sites and maintenance hangars in two countries and designing the transport infrastructure to ship TPLI’s stages across half the globe, the first firing of an integrated Sierra first stage took place late in 1993 at Mitsubishi's Tashiro Test Facility in Ōdate. While the tests of the stage went well, the LE-7 suffered with issues taming its staged combustion cycle to the level required for rapid reusability. Still, the first “battleship” Sierra stage was deemed ready for the 1994 vertical launch-and-landing flights from a launch site at Tanegashima space center. The Fuji stage was proving more of a challenge, as Martin worked through the issues of making a space worthy orbital vehicle fit within the mass margins of a flight-worthy upper stage. It wasn’t until late in 1994 that the first completed vehicle was integrated and ready to be shipped to the White Sands Missile Test range. However, with the financial side of the business temporarily secured, TPLI was still progressing close to schedule.

    The last major international partner NASA courted in the 1990s was Roskosmos, the successor agency to the Soviet Union’s civil space program. Strapped for cash, the agency was eager to leverage its technological expertise for hard currency. While the Americans and Europeans had developed man-tended, short-term space stations, the Soviets had, since the 1970s, been experimenting with ever longer manned stays aboard the Salyuts and then Mir. As the US pivoted from a short-term, LEO-focused program to longer-term missions further out, it was this expertise that NASA coveted. While there were questions as to how much Soviet experience could contribute to the notional partial-gravity laboratory in LEO, there was no question that the hardware the Soviets had developed for Salyut and Mir would prove useful on the planned Lunar Orbit Space Station, and on the in-development Habitat Module for Spacelab. Under the terms of an agreement signed between NASA, Roskosmos, and ESA in 1992, the Russian space agency would provide logistical support and life-support hardware for the Spacelab habitat module, and provide assistance in the development of the life-support system for the notional Lunar Orbit Space Station. For their part, the Russians were happy to have a contract for more flights of the Berkut space shuttles, and a contract to develop propellant-transfer capability for the Groza upper stage so that it could serve as a backup in the event of Lifter or TPLI failures. Such contracts were merely one of several ways the Russian program was seeking to secure the funding necessary to navigate successfully through simultaneous financial, technical, and social crises.

    The dire financial straits in which the Soviet (and then Russian) space program found itself in the early 1990s opened the way to new ventures that were, in some respects, more exotic than logistics for the lunar program. In a (somewhat desperate) effort to find alternative sources of income for the Soviet manned space program, the Soviets had, as early as 1987, begun reaching out to laboratories in non-Warsaw Pact countries and offering them access to laboratory space on Mir at a price competitive with Spacelab. The several-month stand-down of the Space Transportation System in the aftermath of Magellan’s loss gave the Soviets a temporary advantage, which they used to the greatest possible extent, launching experiments designed not just in neutral countries like Brazil, India, and China, but also American allies like Japan and West Germany (and with even US firms expressing interest before Lifter’s return-to-flight restored the earlier status quo). More important than the experiments themselves were the diplomatic and commercial contacts that Russian managers made outside the Warsaw Pact, in particular, with Jeffrey Manber, formerly of the Office of Space Commerce (of the US Department of Commerce), and telecommunications entrepreneur Walter Anderson.

    As the 1980s gave way to the 1990s, the Soviet Union’s economic and political structures continued to erode at an ever-faster rate. Resource shortages were rampant, and the new, more-open government was not having apparent success in combating them. Worse, ethnic separatist movements had begun to erupt from one end of the USSR to the other, from the Baltic states (whose citizens had fonder memories of their brief interwar independence than of their occupation by the Soviet Union) to the Muslim-majority SSRs of central Asia. Matters came to a boil in 1991, when an attempt by the KGB and Communist Party hardliners to restore order and roll back Gorbachev’s reforms backfired drastically. On December 26, 1991, the Soviet Politburo merely recognized reality when it dissolved itself and handed control of the Red Army (and other branches of the Soviet military) to what was once the Russian SFSR, now simply the Russian Federation.

    The end of the Soviet Union did not spell the end of their manned space program, though it did severely complicate it. For one, the primary assembly plant for Russia’s main satellite launcher was now in a totally different country, and under the ownership of an entirely different government. For another, the Baikonur Cosmodrome, from which the majority of Soviet satellites had launched, was in still another country. Finally, the Russian space program was in dire financial straits. Not only was it now to be maintained by a considerably smaller economy (the Russian Federation’s per-capita GDP was roughly ⅓ the Soviet Union’s pre-dissolution per-capita GDP), but it had to fight for its funding in the court of public opinion. In the face of breadlines, drug addiction, an explosion in organized crime, and mass unemployment, appeals to the heroic legacy of the Soviet Union and Russia’s place as a world power fell, more often than not, on deaf ears.

    Like two satellites separating from one another after orbital insertion, the Ukrainian and Russian space programs began to diverge very shortly after Ukraine gained her independence. Russian military officers very quickly came to regret the decisions of their Soviet predecessors to terminate Soyuz and Proton production. Though the anemic Russian economy did not provide enough funding to launch many satellites, enough had to be manufactured and launched (to complete the GLONASS navigational system, to replace aging Molniya-orbit communications and warning satellites, and to perform other critical military and civil infrastructure tasks) that they would swiftly have exhausted the remaining supply of warehoused Soyuzes and Protons. Ironically, what saved the Russian program from total dependence on Ukraine was Raskat’s reusability--the 10 boosters in the Russian fleet could, assuming no losses, supply the Russian Federation for most of the 1990s and even beyond (depending on maintenance quality). The Groza core stage was a more troubling matter, as it was expendable, but Ukraine was dependent enough on Russia for imports and exports that purchases were, for the moment, reliable. It was a difficult dependence to swallow for a military hierarchy so used to autarky, but there was no way around it--restarting Soyuz or Proton would take at least several years and a larger investment than the Russian Duma was willing to make in 1992.

    NASA’s partnerships with ESA, NASDA, and Roskosmos were critical to the effort to shepherd the Space Exploration Initiative through the US congress. Though there was no Congressman or Senator with a particular grudge against NASA in the 1990s, American legislators were eager to cut off small chunks of the NASA budget in order to reduce taxes or at least to shore up their own “fiscal conservative” credentials. While there was no serious effort in the discussions over the FY1992 and FY1993 budgets to utterly defund SEI, there were proposals for reductions in funding and extensions to the schedule. A memo circulated at NASA headquarters in early 1992 contained a copy of the infamous “fusion never” graph, which, when first published in 1976, stated that, if the 1978 level of fusion energy research remained constant, there would never be a commercial fusion reactor in the US. As the memo elaborated, “much as a rocket can burn a lot of fuel and stay on the launch pad if its weight is greater than its thrust, a program can, in fact, burn a lot of money without doing anything.” NASA staffers and industry lobbyists set to work persuading congressional staffers of the importance of funding the now-international Space Exploration Initiative, implying dire consequences would result from a lack of American leadership on an international program in space.

    The effort was much harder than it might have been a decade or two earlier, as, without the Soviet menace, it was difficult to paint a plausible scenario of any nation other than the US taking the lead in space. Legions of staffers worked long hours to find new talking points. Eventually, they hit on a number of points that were emphasized to varying degrees depending on the relevant Congressman’s interests. The collaboration with the Russian Federation on the Space Habitat partial-gravity laboratory appealed to both security-interested congressmen anxious to prevent a drain of Russian talent into Iran, Iraq, or China, and to optimists eager to create in Russia a sincere American partner. Collaboration with the European Space Agency and Japan similarly appealed to those who recognized the long-term importance of America’s allies in supporting future interventions around the world. The possible utility of the the new Space Habitat as a laboratory for biomedical research with terrestrial applications was also brought up, though the similarity of that argument to old promises of microgravity wonder-drugs was not lost on veteran Congressmen who had heard those promises in the 1970s. Together with the typical “jobs at home” arguments that easily mobilized space state congressmen, these arguments helped keep SEI’s various programs funded even as the Bush Administration gave way to the Clinton Administration.

    The success of the Space Exploration Initiative must be contrasted against the failure of its counterpart in the field of particle physics, the Superconducting Super Collider. As it had treated spaceflight, the US spent much of the Cold War treating fundamental physics research as a field of soft power projection, a way to demonstrate American supremacy in science. Officially begun in the mid-1980s, the Superconducting Super Collider was to be the latest in a line of increasingly large and sophisticated colliders built in the US. However, it floundered on the rocks which NASA and its contractors had narrowly avoided during SEI and during the earlier effort to fund the Space Transportation System. Like the NASA programs, the SSC lost a great deal of support in the aftermath of the Soviet Union’s collapse, as the Russian Federation was in no place to challenge America’s leadership in particle physics, and as budget-cutters, led by Kansas congressman Jim Slattery (who, at the same time, was also challenging the B-2 stealth bomber) eyed the program as a source of Peace Dividend savings. Unlike its aerospace counterparts, its supporters were concentrated almost exclusively in Texas, where it was to be built, and to a lesser extent at the handful of research laboratories supporting the effort. This limited greatly the amount of Congressional support it could rally. The SSC also failed to generate serious partnerships with American allies in Europe and Japan, who, for their part, preferred to develop their own experiments, whether under the auspices of CERN or under their own national and university laboratory systems. Most crucially, the SSC’s budget had inflated sharply since the project’s initiation, from $4 billion quoted in 1987 to $12 billion in 1993. While this was still a drop in the bucket compared even to NASA’s cost estimates for SEI, the sudden budget increase embarrassed the program’s backers and opened them up to allegations of mismanagement and incompetence, particularly since a great deal of the program’s staff were new to particle accelerator operations. SEI’s planners, by contrast, were able to point to the low cost of Space Lifter operations over the years and the fact that that program had come in on-budget (after adjustment for inflation) during its development to defend their programs from similar allegations. Furthermore, the comparatively low costs of fixed-price launch contracts (which were to be used for propellant launch to Low Earth Orbit) appeared to ensure that, when NASA quoted a $40 billion program cost, it would come in at that value.

    As George Bush's first term proceeded past his first midterm elections, his space troika had proved successful in creating a plan and marshaling support in NASA's management, on Capitol Hill, and around the world for the Space Exploration Initiative. While they had achieved a major turnaround in the fortunes of an agency that had seemed rudderless after the Magellan failure, the task remained to see the funding that had been secured against the headwinds of the Peace Dividend turned into real hardware. With the approval in the FY 1992 budget in late 1991, the first funds were made available to power the program out of the glide it had been in since the Return to Flight and turn the early studies laying out the Space Exploration Initiative into measurable progress and real hardware.
     
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    Chapter 15: Spool-Up
  • “A marginal SSTO is a great TSTO.”
    “By extension, a marginal TSTO is a great 3STO.”

    Hand-written notes on NASA MSFC memo during STS planning, 1969​


    Chapter 15: Spool Up

    With a loud whine, hydraulic actuators opened the air intakes for Constitution’s twin Auxiliary Power Units. Supersonic air slammed into the compressors of the small jet turbines, beginning to turn their cores. As the lights on the cockpit displays indicated the doors locked open and the RPM gauges rose off the stops, Young and Crippen began the startup procedures. Crippen read off the checklist as Young opened the valves which fed peroxide, then kerosene to APUs. The decomposing peroxide, flashing to superheated steam as it passed the catalyst beds, hit the starter turbines on the two little jet turbines. As they drove the rotation rates above the critical threshold for start, the kerosene flow was set and a burst of spark lit the burners. As the turbines continued to spool on their own power, the peroxide flow was cut, its job done. The whine of the units, conducted through the frames, contributed a barely audible tone to the cabin as Constitution left her wake far behind.

    With the two generators picking up the loads of
    Constitution’s equipment, another gauge showed that the bleed pressure to the main engine bank was also rising to nominal. As Crippen cross-checked the gauges and called off the checklists, Young began opening the engine inlet doors, starting with the inboard pair. As with the smaller auxiliary units, ram compression on the fans was enough to get the core turning, but a burst of compressed air was necessary to boost the engines above starting speed. As they spun, the fuel pumps began injecting a fine mist of jet fuel into their combustion chambers. The rarefied but high-velocity inlet air might have been a problem, but Constitution shared her powerplants with the latest generation of fighters and bombers in the American fleet. Their original designers had known engines might have to light at such conditions, and as with most systems on the Lifter, the jets were over-engineered and redundant. She could have flown with only six active engines, and as it was, 7 out of her 8 lit on the first attempt. The last, moments later, spooled up under the full attention of the flight crew and controllers back at Houston examining the telemetry, even as their fellows monitored the ascent of Endeavour to orbit. The whine of the APUs was lost in the distant rumble of the engine bank.

    The starters were secured, and Young adjusted the throttles for their flight back to Kennedy. Opening valves in the tanks, they began to bleed off the residuals left over from the launch, sloshing in gutters on the former sides, now the bottoms of her vast propellant tanks.
    Constitution briefly acquired a tail of RP-1 and boiling LOX vapor to join the wide blended contrail from her jet bank as she completed her conversion from rocket to aircraft. The roar of the engines trailed far behind with the sonic shock-wave as Constitution started her Mach 2 speed run back to shore and Kennedy Space Center.

    As the Space Exploration Initiative continued to spool up efforts to turn Bush’s selection of an Option B lunar access system into reality, new-start projects continued to sprout like mushrooms after rain in the fertile grounds of the increased budget. The most major projects, like the permanent space habitat and a reusable tug capable of accessing cislunar space, were key to the initiative. These large development projects were hotly debated within NASA and industry sources, as managers sought to define the program’s objectives and firms competed to shape the SEI’s version of space exploration hardware to fit the bids they believed they could put forward. The new surge in development money had other beneficiaries, though, as projects less closely related to the Space Exploration Initiative fought to tie their pet concepts to the new lunar focus in hopes of securing some fraction of the funding. The benefits for the projects which succeeded in securing such windfalls were large, but even securing a place on the starting line was only the beginning of the battle to bring a project to fruition. Managers would have to guide their projects through all the ramp-up challenges from contracting to delivery if the Space Exploration Initiative was to pull the American space program out of its post-Magellan doldrums and point it back on a course to the moon. The cost of failure was potentially high, but a success could ignite a new blaze of American innovation even hotter than that unleashed by the Apollo program.

    In Low Earth Orbit, the Space Exploration Initiative was most visible in the new Space Habitat, which came to be known as the Armstrong Partial Gravity Laboratory. Named, officially, after Harry George Armstrong (the founder of the USAF’s Department of Space Medicine, who had identified the altitude limit past which humans could not survive without a pressure suit), the laboratory’s purpose was to validate life-support hardware for a continuously-manned outpost in space and to identify the gravity limit below which human health really began to suffer. Few, however, failed to notice the fact that the station shared a name with that famous hero of the Apollo Program, Neil Armstrong, nor that its mission bore a striking connection to his.

    Armstrong began its development as a series of design studies for a permanent habitat module for Spacelab, which would enable the microgravity outpost to transition to a permanent laboratory. While popular with biomedical researchers eager to gauge the effects of very long-term exposure to microgravity, the idea of permanently stationing crew on Spacelab had a mixed reception elsewhere. Some European officials were eager to find opportunities to expand the European astronaut corps, while others (representing materials scientists on both sides of the Atlantic) objected to the inherently greater vibrations induced by a crewed presence on the station, which would compromise the microgravity environment or require extensive redesign of experiment pallets to mitigate the damage. A minority of scientists (primarily those whose experiments had been compromised by mechanical breakdown and could not be repaired for weeks to months until a Shuttle brought a crew up for a visit) were more optimistic about the possibilities for servicing experiments in LEO. The combined effects of all these arguments saw the Space Habitat physically detach from Spacelab, becoming a co-orbiting platform that would maintain position four kilometers aft of the older laboratory.

    Once Armstrong slipped the surly bonds of Spacelab’s docking port, it began to attract attention from those elements of NASA concerned with interplanetary missions and the still-novel concept of artificial, centripetal gravity. The first proposal called for a heavy centrifuge to be mounted inside the Space Habitat, to enable testing of mice at lunar and Martian gravity levels. More ambitious proposals followed, calling for an entire habitable section of the spacecraft to be spun up. Though advocates of an all-microgravity setup pointed out that this would eliminate data on long-term human exposure to microgravity entirely, the rotation-advocates pointed out that what data they had already gathered on Spacelab, Shuttle, and earlier programs going back to Skylab and Gemini already indicated that microgravity was a severe hazard to astronaut health, inducing severe muscle and bone atrophy if not counteracted with an intense daily exercise regime (which did not entirely eliminate the problems). Long-term missions to the Moon and Mars would either require artificial gravity in-transit or at the destination to eliminate these problems, or spend the overwhelming majority of their time in a weak gravity field. In light of such considerations, they argued, it was more important to establish the lowest necessary acceleration to prevent the atrophy observed since Gemini.

    For a large part of the 1980s, Space Habitat languished in design studies, and the debate between a microgravity habitat and a partial-gravity habitat was hashed and rehashed several times over. It was not until the Wetlab demo flight that the argument began to turn decisively toward the partial-gravity side, as Wetlab demonstrated a method by which partial gravity could be achieved relatively cheaply and easily, by using the discarded S-IVC as a moment arm. Gone were the Von Braun-style wheeled space stations and folding toroids; by 1988, most partial-gravity proposals for Space Habitat called for an advanced derivative of Wetlab, with a docking port coaxial with the spin axis, a dry Equipment and Service Module (ESM) on one side, and the immense Wet Workshop on the other. The design eliminated the difficulty of designing rotating seals between spun-up and despun portions, but set a firm upper limit on the rate of rotation (and therefore maximum acceleration), past which rendezvous and docking for a crewed vehicle would be extremely difficult. Since Wetlab already had a fairly long moment arm, this was deemed an acceptable limit that would still allow tests at Martian gravity levels.

    The Space Exploration Initiative suddenly brought the Space Habitat out of the darkness and into the light. As the initiative reoriented NASA from a focus on Low Earth Orbit to long-duration missions to the vicinity of the Moon (and later the Moon itself), the Space Habitat became a crucial tool for developing the long-term life-support technologies and techniques that would be necessary to sustain such missions. By 1990, the consensus at the major NASA centers (Ames, Johnson, and Marshall) had reached an approximation of Space Habitat’s final form--a formation-flying, partial-gravity laboratory co-orbiting with Spacelab. It was this design that entered the NASA budget request for FY1991 as the Partial Gravity Space Habitat, which would finally be named “Armstrong” in the FY1992 request.

    Once the spacecraft was defined, the next task was to assign development for the three main components: the Wet Workshop and its associated hardware, the dry-launched Equipment and Service Module (ESM), and the Docking Module. The Wet Workshop contract, naturally, went to McDonnell-Douglas, while the Docking Module was assigned to Grumman Aerospace, which leveraged its experience with the MPEM to build the new pressure vessel. The single largest and most complex part of the station, however, fell to the European Space Agency and its prime contractor, Deutsche Aerospace Aktiengesellschaft (which had inherited ERNO’s work on Spacelab through a series of mergers). Having studied the Spacelab service module (which had been largely developed by Marshall Space Flight Center), DASA set to work combining heritage Spacelab systems with new innovations.

    In addition to more advanced computers, the Equipment and Service Module took on a number of improvements to its power generation and life support systems. A number of Russian systems developed for the Mir space station found use aboard Armstrong, including deposition-based CO2 scrubbers (replacing the fragile and constantly-replaced zeolites used on Spacelab). Armstrong’s photovoltaic systems were considerably more efficient than those developed a decade earlier for Spacelab, and were themselves supplemented by a pair of experimental solar-dynamic power systems jointly developed by the Lewis Research Center and the US Department of Energy. Though only providing a fraction of the station’s power requirements (roughly 20% each), the two experimental systems, the Solar Brayton Engine Demonstrator and the Solar Stirling Engine Demonstrator, were a valuable testbed for future power systems designed for the outer solar system, and had a considerably better power-to-weight ratio than the existing photovoltaic arrays. Such systems had been proposed for demonstration on Spacelab, but the need to maintain a vibration-free environment on that station had prevented their installation.

    The portion of the Space Exploration Initiative’s hardware which prompted the largest debate was the interorbital tug. The tug was a critical part of Bush's Space Exploration Initiative: the process of returning to the surface of the moon, not just once or twice but to stay, was a vision common within NASA, but it couldn't be accomplished without routine and cost-effective access between LEO and other points in cislunar space. This observation wasn't new: the Space Tug was a concept which had been under study for longer than the Lifter itself, with its earliest ancestors being the tugs which had proliferated in studies during the Apollo era, and formalized in the same Integrated Program Plan which had subsequently birthed the Space Lifter. In these plans, reusable chemical Space Tugs and orbit-only Nuclear Shuttles had served to carry payloads launched by Space Shuttle and Saturn V to the moon, to geostationary orbit, and to staging points for hardware to be assembled for missions to Mars or beyond.

    In the mid-eighties, as the Space Transportation System had stepped up to an astounding launch cadence and the Space Shuttle had proved to live up to at least some of the promises surrounding applications for lower-cost manned spaceflight, the Orbital Transfer Vehicle been added back to planning for lunar and Mars missions, now envisioned not only as a cislunar tug but also as a possible booster for Mars missions, using chemical propellants for boosts but in some designs using large heat shields assembled in orbit for more propellant-efficient returns for reuse. By the time the SEI was being laid out, these concepts had been joined by renewed interest in nuclear options, spurred by the military's Project Timberwind development efforts, as well as by new interest in high-power, high-efficiency solar or nuclear electric ion or hall effect systems. Thus, when the Congress approved the funding of the development of an interorbital tug to facilitate the SEI's lunar vision, it was far from clear to any of the congressmen just what they’d bought.

    NASA administrators and engineers spent much of 1990 refining the initial concepts of the Lunar Transfer Vehicle even as funding for the program was advancing in Congress. These early studies, funded out of FY1991 funds advanced for spending in 1990, worked to prune down the wide spread of initial concepts into a single vehicle architecture which could be put out for bid. The wildest ideas and those furthest from production were the first to go. Although electric propulsion offered tremendous ability to move large cargoes with minuscule expenditures of propellant, no system of the scale required to fly a multi-ton manned tug had ever been flown. The technology was simply too immature for immediate consideration. The same judgement was also rendered to nuclear thermal rockets. While the Timberwind project had recently found that the technological foundations were strong, the study had explicitly not dealt in depth with the major worries over multi-burn designs, inspection and reuse in space and on the ground, and the surrounding cost structure. In the end, like electric propulsion, nuclear thermal was simply trapped too far down the technology readiness levels to advance onto the critical path.

    The elimination of exotic propulsion for the moment meant that traditional chemical solutions would have to suffice, but even within this realm there were a myriad of competing options, from simple conversions of existing stages to modular and drop tank systems assembled in space and refit at the Space Habitat to aerobraking discs and ballutes that would capture back into lower orbits. Here NASA objectives came into sharp opposition, and managers bogged down, caught between lessons learned over the tenure of the development and operation of the Space Transportation System.

    The first lesson was the benefit of re-usability and already-built infrastructure to reduce operational costs and protect programs against cancellation. While the expendable programs of NASA's early days, from Atlas to Titan and from Mercury to Apollo had had to fight every year for ongoing approval, the Space Shuttle and Space Lifter had never in almost a decade been in serious danger of cancellation. Other expendable systems illustrated the same: because an expendable vehicle always required new hardware, any interruption in demand could terminate a program or spike costs to the point of cancellation. Even the recent temporary respite for Titan III emphasized this point: the Titans could not be released by the USAF for commercial use since they were pulled from a strictly limited stockpile, and the costs were higher than Lifter even ignoring the storage and stand-up costs. In a break from the Apollo tradition, NASA managers hoped that the lunar Space Tug could be an opportunity to build an infrastructure to reusably and cheaply access the moon. They hoped that LTV and the rest of the SEI could combine to form a sustainable, cancellation-proof infrastructure for access beyond Earth’s orbit, much as the Space Transportation System did for LEO. Such thoughts lead to elaborate schemes, with orbital servicing and long-life aerobraking systems which would not only pave the way for other applications but help justify investment in orbital infrastructure.

    Sharing some of the same drive to apply lessons from the STS to the LTV was another faction which drew on the lessons learned more recently during the Magellan accident investigation. This group stressed the importance of long-term inspection and tear down to a reliable reusable vehicle, comparing the reliability of the Space Lifter booster and Space Shuttle glider even after stints of six to a dozen flights between SLIP inspection periods to the expendable S-IVC stage which had failed in the accident. Whenever possible, they stressed the ability to conduct full tear down and refit of reusable vehicles.

    While the possibility of extensive orbital hangar infrastructure at the Space Habitat had been an option, the two viewpoints had been in harmony, but the restrictions from a third managerial viewpoint would throw them into a battle only one side could win. This third objection was the cold budgetary realities of the program which Congress had approved: the Space Habitat would not be a massive space operations center where a tug could seek safe harbor for refueling, inspection, and refit, but a smaller orbital outpost aiming to provide mainly biomedical and operational data for long-duration manned missions. Moreover, the part-wet, part-dry single-launch Armstrong Station design that was emerging as the final station architecture was entirely incapable of hosting a hangar, both for size reasons and because of its tumbling end-over-end artificial gravity generation. NASA lacked the funding to even consider a third Space Dock station above and beyond Armstrong and Spacelab that could play harbor to the tug, so any tug would have to return to Earth for any servicing and inspection. Though not every flight, it would still be necessary to disassemble and reassemble any of the more baroque designs to fit them into the Space Shuttle cargo bay at regular intervals, which could easily consume much of the cost and engineering savings over an expendable stage.

    Both of the other factions would have to compromise: the aerobrakes preferred by many of the infrastructure designs were all many times larger than the Shuttle cargo bay, and couldn’t be returned. Several studies were conducted on tugs with expendable heat shields, which could be evaluated by the same astronauts which would disassemble and return the more complex engines and tank subassemblies for integration with a new shield and relaunch on Lifter. However, the problems for the overall architecture were serious, and the designs were largely rejected from consideration, though large one-use shields remained in consideration for other applications like Mars. For their part, the reliability faction had to give up extensive hands-on inspection by astronauts every flight. In exchange, they would get regular inspections on the ground, in ordinary clean room conditions instead of whizzing along at kilometers per second in a space hangar. What emerged was a new architecture: a chemical modular architecture, with all inspections and overhaul performed on the ground and minimal manned turnaround support in space. Though modular designs were acceptable to meet this goal, their assembly had to be minimal, and they should be reusable to the maximum extent practicable. The result was that the LTV design process shifted from a wide-open design space to a more restricted, perhaps nearly non-existent one. The design had to have subassemblies small enough to fit inside Shuttle for return, while also being simple enough to cost-effectively tear down for return. Under such limits, the replies to NASA’s request for proposals when the LTV was put out for bid had to be unorthodox to meet the constrained trade space.

    The design for the LTV was finally put out to bid in 1991, and the resulting proposals were incredibly diverse. Several companies submitted multiple proposals, with each testing the bounds of one or another of the design ground rules. The highest-rated Lunar Transfer Vehicle designs, upon analysis, were in many case those that strayed furthest from assumptions about what the Space Tug would have been only a few short years before. A number discarded the traditional assumptions of hydrogen/LOX propellants and instead considered a variety of hydrocarbon propellants, mixing LOX with methane, propane, and kerosene, or even using alternate propellant pairings like Grumman’s studies of kerosene/hydrogen peroxide. Initially selected for higher storage densities for smaller tanks, many combinations also yielded pairings more easily stored on orbit than the traditional but evanescent hydrogen. The designs of modular tanks led several firms to consider not just a modular tug, but a multi-stage one--the traditional solution to getting more performance out of limited mass.

    The winning proposal, by McDonnell-Douglas, added a novel approach to aerobraking to these basics. McDonnell-Douglas engineers realized that traditional aerobraking heatshields had to be so large due to the assumption of a one-and-done braking maneuver--a dive deep enough and hot enough to scrub off all the vehicle's excess velocity in a single pass, just as a shield designed for an orbital entry did. To dissipate the large heat pulse of such an entry, the shield had to spread it over a large area and use exotic materials. However, if the braking was spread over multiple perigee passes, it would have correspondingly shallower dives into the atmosphere and lower heat input. Studies McDonnell engineers discovered in archives from the 1970s had found this sufficient passes could yield heat shields which didn't require extensions, but could instead be wrapped around the body of a traditional stage which fit within the Shuttle cargo bay. A small "flare" to stabilize the stage would have to be disposed of on each service mission, but the entire heat shield of the "small brake" design could be built of less exotic materials and still offer aerobraking’s benefits to weight.

    McDonnell’s final proposal was wildly divergent from the original 1990s concepts, but it almost wrapped back around to conventional: a cylindrical stage with a docking collar on each end just barely capable of fitting within the Shuttle cargo bay. Two stacked atop one another and fired in series were capable of sending a substantial payload into lunar orbit. Interest from Mars-focused McDonnell engineers and density impulse trades lead to their proposal calling for a new, methane expander-cycle engine, sized such that a cluster of four could fit around the aft docking collar. Even so, the engines' fit was tight, requiring them to gimbal out to allow the docking port to extend for assembly and gimbal in to clear the shuttle bay doors on return. Pratt & Whitney, the manufacturers of the RL-10 expander engine since its introduction, were consulted heavily on the design for this new expander cousin. A heat-shield would close over the payload end of the stage for aerobraking passes, with the engines protected by the stabilizing flare, which would be discarded before return to Earth for inspections when necessary. To further reduce heat shield loading, the hottest portions of the nose would be actively cooled with methane during entry. The four-day return to LEO from lunar transfer orbit for the second tug and two-day return to LEO for the first tug would slightly reduce the maximum tug flight rate, but also meant that the actively-cooled heat shield should be indefinitely reusable, though the niobium alloy selected could manage multiple complete missions with purely passive heating as an emergency measure.

    The tugs were interchangeable: any tug could be a first stage or a second stage for a lunar mission or be used independently with a partial propellant load for geostationary orbit missions. Two or more tugs could be launched together on a single Lifter with a partial propellant load, and attachments allowed for propellant transfer to top them off in orbit, even using other tugs as tankers. Their methane/oxygen propellant and low-pressure expander engines meant there was little to go wrong: they could last fueled in orbit nearly indefinitely, and the engines should have lifespans similar to RL-10s, which had lasted the equivalent of hundreds of tug missions on the test stand. Even so, the entirety of any damaged or worn tug, less the flare, could be returned to Earth with a single Shuttle mission, which could also carry up a replacement fresh from refit. NASA selected McDonnell’s proposal in August 1991. A follow-up contract went to Pratt & Whitney for the design and test of the required Lunar Transport Main Engine, proving their early design contributions to be worthwhile. Although small enough that Pratt & Whitney’s early full-scale mockups could fit in a car seat, the expectations on the engine were high: it would have to live up to the reputation of its cousin, the expander-cycle RL-10, and bear the schedule pressure of the entire lunar program on its tiny thrust mounts. It was, in point of fact, the first major clean-sheet engine development project in the United States since the cancellation of the SSME project two decades prior. Pratt’s victory was contested by Aerojet and Rocketdyne, who argued their relationship with McDonnell during the design process made the contract award unbalanced. Aerojet was eventually satisfied by winning the contract for the LTV’s methane/oxygen thruster system, while Rocketdyne would have to content itself with its unquestioned dominance of every other STS engine. Only TRW, whose pintle engine design they hoped would have more applicability in future alternative roles, was entirely shut out. Still, by the end of 1991, the design of the tug had been settled and planning was in work to hopefully see it fly by the notional 1996 date. NASA planners could finally turn their attention to how it might be used to implement the longer term goals for lunar orbital stations and for a renewed series of lunar landings, while engineers at McDonnell and P&W set to work beginning to turn the designs of the LTV and the LTME into reality.

    The decision to use chemical propulsion for the LTV did not mean the end of electric thruster development. Since the 1960s, electric propulsion had been a favored topic of research on both sides of the iron curtain. In the Soviet Union, these efforts bore fruit in the form of Hall-Effect Thrusters that, since 1971, have provided Soviet and Russian satellites with reaction-control capability. Using far less propellant than chemical thrusters, these HETs greatly extended Soviet satellites’ operational lifespans. The long lifetimes of HET-equipped satellites made the technology particularly attractive for American and European commercial satellite manufacturers, and made HETs one of the first advanced Soviet aerospace technologies to cross the ruins of the Iron Curtain. Following the launch of a small demonstration satellite (sponsored by MIT and the Space Studies Institute), GeoStar began designing HETs into its next-generation communications satellite design. Ford Aerospace, not to be outdone, also equipped its FS-1300 geostationary satellite bus with Hall-Effect stabilization technology, though they did not deploy the first so-equipped satellite until 1998.

    While the Soviet Union focused on Hall-Effect reaction control for earth-orbital applications, American researchers set their sights further outward. From the 1960s, researchers at Lewis Research Center had imagined that their low-thrust propulsion systems would power eventual human missions to Mars and unmanned probes to the outer planets. Perhaps for this reason, the American low-thrust propulsion effort failed to attract as much official support as its Soviet counterpart; after two demonstration missions in 1964 and 1970, the American effort mostly went dormant until the late 1980s. When it was finally revived, the effort began, not at Lewis Research Center, but at its old rival the Jet Propulsion Laboratory. It was there that a team of engineers proposed, in 1987, to launch a pair of low-mass, low-thrust, low-cost spacecraft to the Moon. Dubbing their proposal “Lucky 7,” after one of them turned a presentation slide with “L L L” written on it upside-down, the team designed a 150-kg spacecraft bus equipped with two xenon-propelled Gridded Ion Thrusters. Designed to fly all the way from Low Earth Orbit to a polar Low Lunar Orbit, each Lucky 7 spacecraft would carry one instrument. The first, a gamma-ray spectrometer (left over from the instruments built for the Apollo 19 mission), would be designed to detect the presence of heavier elements (phosphorus, potassium, and others) in the lunar crust, while the second, a neutron spectrometer, was designed to characterize the presence of volatile elements in the Moon’s crust. Together, the two spacecraft would deploy from a Space Shuttle payload bay and slowly thrust toward the Moon, reaching their target orbit two years after launch. In the process, they would demonstrate the operation of a solar-electric thruster in near-earth and cislunar space, proving a concept for solar-electric tugs from Low Earth Orbit to higher destinations and measuring the exact impact of the Van Allan radiation belts on spacecraft slowly crawling through the dense, energetic belts. The actual scientific observations they’d perform at the Moon, compared to this value, were an afterthought in the original JPL presentation.

    Lucky 7 floundered for a time at NASA. The Jet Propulsion Lab was more concerned, in 1987, with planetary science, particularly that performed by very large, very high-budget missions like Galileo and the Mariner Mark II series. Lewis Research Center, for its part, was open to the project, and the JPL engineers found much support among the Space Shuttle Program Office at JSC, who were always happy to find a payload to fly in the Shuttle payload bay. NASA headquarters, however, was reluctant to allocate funding for the small program, struggling as it was to get the Mariner Mark II program funded. It was not until the announcement of the Space Exploration Initiative that Lucky 7 (by 1990, given the more dignified name of “Inter-Orbital Navigator,” or ION) suddenly found a wave of new support from NASA’s leadership. Influential voices at NASA headquarters, with an eye on long-term missions to Mars, had been proposing a solar-electric tug (with a heavily-shielded payload bay) for years to transport payloads to geostationary orbit or to earth-escape. Between SEI and the panels before it that called for NASA to develop such a reusable in-space propulsion capability, government support for such a vehicle had never been higher. ION went, at least briefly, from a cheap technology demonstrator to a critical step on the path to the Moon and Mars.

    This privileged status was not without its drawbacks. When the astronaut office pointed out that spending months to years in the Van Allen belts or even the lesser interplanetary radiation environment would have a deleterious effect on crew health and morale, making a high-thrust chemical tug necessary anyway, NASA’s reference Moon and Mars missions abandoned the solar-electric tug, instead distributing more flights onto the chemical tug. ION went from a critical step on the path to the Moon to a critical step on an unknown path. Though the MIT and SSI work in bringing Russian Hall-Effect Thrusters over to the West had helped bolster some support for low-thrust propulsion research at Lewis (which designed a cislunar tug with chemical main propulsion but electric station-keeping capability), the prevailing momentum toward more use of commercial hardware at NASA had ironically come to favor hardware developed in the Soviet Union.

    Equally ironically, ION’s saving grace turned out to be its meager scientific payload. Just as the Apollo program was preceded by Ranger and Lunar Orbiter and Surveyor, so the new return-to-the-Moon would be preceded by a small fleet of unmanned spacecraft to characterize regions of interest in those parts of the Moon far from the Apollo landing sites. Though JPL had already drawn up plans for a Lunar Observer spacecraft, to go with the Mars Observer planned for launch in 1992, ION, as a much smaller set of spacecraft, could be ready to fly by the end of 1991, thus reaching lunar orbit by 1993, several months before Lunar Observer. The two spacecraft would provide additional data on the contents of the lunar crust, and simultaneous tracking from Earth would allow scientists to collect high-quality data on mass concentrations in the crust, allowing them to map the notoriously “lumpy” lunar gravitational field, aiding planners for future lunar orbital missions and aiding geological studies of volcanic activity on the Moon. This argument won the day at NASA, and a pair of spacecraft originally designed to test technology, whose cosmic sensing instruments were almost cosmetic, were saved through the intercession of geologists.

    The 1990s also saw advances in propulsion below the Karman line. The European effort to replace Ariane took a sharp turn for the exotic with ongoing work in Britain on their Horizontal Take-Off and Landing (HOTOL) project. Based on the work of British engineer Alan Bond, the HOTOL project proposed to use pre-cooled jet propulsion combined with a rocket engine cycle to launch an aircraft directly from the runway to orbit. However, looking at the experience of the American Aerospaceplane project of the 1960s, British Aerospace was hesitant to commit to a full development effort for a single-stage-to-orbit vehicle, preferring instead to leverage the engine technology for a first-stage, horizontal-landing booster. British Aerospace entered its own air-breathing design into the argument over how to loft a reusable core stage off the ground. The HOTOL design submitted called for a runway-launched air-breathing booster that would propel an upper stage to Mach 7, while liquefying enough atmospheric oxygen to fill up an upper stage. The upper stage would be propelled by a fairly conventional rocket--the most revolutionary aspect would be that it separated from the booster heavier than it launched off the ground.

    The HOTOL proposal was both reasonable, economical, and exciting. It promised full-reusability on a two-stage launch vehicle, with a technology that was just close enough to be feasible. Compared to the cautious conservatism of the Ariane design, it was a breath of fresh air, one that was appealing to engineers across Europe. In 1984, following more detailed design studies by Rolls Royce on the liquid-air-cycle engine proposed for HOTOL, Arianespace officially partnered with British Aerospace to develop the HOTOL launch vehicle, with British firms developing the reusable booster and continental European firms developing the upper stage and hydrogen-burning main engine.

    The new booster design was comparatively smaller than the Space Lifter architecture, aiming for a maximum of 16 tonnes to Low Earth Orbit. Among other payloads, this would enable the new RLV to lift an expanded manned capsule based on the Hermes capsules in development for the lunar program, and the small size would enable reduced mission costs. In observing their American counterparts, Arianespace managers noticed that satellite operators were often reluctant to share their rides to orbit with other companies, as the logistics of arranging the shared launch tended to induce delays as suitable partners were found. As a result, they aimed to keep launch costs low enough that single-satellite launches would be economical. Though the Ariane replacement system would not be ready until around 2000, its potential to reduce the cost of space access added to the wave of investment that TPLI and the planned Low Earth Orbit constellations drove in the early 1990s, spurring ever more grandiose plans to use the reusable systems to their full capacity.

    The designers of technology demonstrators like Inter-Orbital Navigator probes and the new European efforts in airbreathing space launch systems hoped their technologies could one day contribute to the broader exploitation of spaceflight. For the moment, however, they were just following in the shadow cast by the Space Lifter and the new projects started to fuel the Space Exploration Initiative’s return to the moon. They held promise, but the center of gravity of advances in spaceflight lay beyond their development horizons. They were scarcely less remote from the action than the general public. Though the data these developments returned would be of value later, their immediate interactions with the return to the moon was limited to justifying budgets and grants while tracking the progress in trade papers of the vehicles which would, should they succeed, carry humans farther than they had gone in decades.
     
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    Chapter 16: Tracking
  • "Intelligent life, once liberated by the resources of space, is the greatest resource in the solar system ... the highest fulfillment of life is unbounded intelligence and compassion."​

    Chapter 16: Tracking


    As Constitution and Endeavour roared into the darkening Florida sky, their instruments transmitted signals unceasingly to the Atlantic Missile Range’s tracking computers. Electrons ran back and forth millions of times per second on finely-manufactured transmission antennas, inducing the minute oscillations in magnetic and electric fields that propagated down to receivers on Earth.

    Constitution, when she had been at her greatest downrange distance, was below the horizon and invisible to observers at Cape Canaveral; Endeavour remained so, as she continued her long arc around the Earth. The two craft beamed their signals instead to the USNS Redstone, a former oil tanker built during the Second World War to support Allied forces in the Pacific. Now, she provided logistical support of a different kind, receiving and retransmitting signals from the two spacecraft, boosting them over the horizon again to Cape Canaveral. Redstone’s sensitive tracking antennas and telephoto-lens cameras continuously adjusted to match the spaceships’ trajectories, following a combination of pre-programmed data about the planned trajectories and feedback from their own computers. Today, Redstone supported a human crew, but she was getting on in years, and her replacements, the great TDRSS satellites, had already started going up. Like many machines before her, one of her last services was to help render herself obsolete.

    Millions of times per second, electrons ran back and forth. Thousands of times per second, sensors lining the two spaceships’ propulsion and life-support systems took their precise measurements. Hundreds of times per second, these measurements made their way down to
    Redstone and back to Cape Canaveral and to Houston, where they were automatically routed to flight controllers’ computers and to archaic recording equipment, which, built years before the craft they now monitored, carefully embedded the information onto strips of iron oxide.

    In such manner, vital information about the performance of rocket motors and human bodies made its way to men (and, more and more often with every passing year, women) who could not themselves experience the crushing pressures of a combustion chamber or feel the pulse of the men who, at that instant, were the fastest on Earth.


    The transition from the Bush Administration to the Clinton Administration caused a great deal of concern at NASA and its prime contractors (and their surrounding communities) as to the fate of the Space Exploration Initiative. The National Space Council and NASA had assumed that President Bush would have two terms with which to implement their recommendations, but the lackluster performance of the American economy and Bush’s backtracking on his promise to not raise taxes left him a one-term President. The disruption at NASA and the NSC was not so great as might have been feared--the NSC’s successful implementation of the first steps toward the SEI showed the competence of its leaders, and the imminent debut of a new American launch vehicle (one built and operated without much oversight from NASA, at that) underscored the need for a council to advise the President on all aspects of American space policy. Administrator Goldin, for his part, continued his work at the agency, which is not a surprise given his party affiliation.

    President Clinton, to all accounts, had not given space policy a great deal of thought during his election campaign, and as Governor of Arkansas it had never been on his radar. When he took office in 1993, he was thus a fairly blank slate on which his advisors could write. Those parts of the Space Exploration Initiative that had been approved in 1991 and 1992 were still early enough in their development that, if he had so chosen, he could have cancelled them and replaced them with something else with minimal complaint about sunk costs. However, neither his Vice President, Al Gore (who took Dan Quayle’s place on the NSC), nor his OMB director, Leon Panetta, took a decisive stand against the programs. The Space Exploration Initiative’s programs (Armstrong and the Lunar Transfer Vehicle) were, at the time, on-budget and on-schedule, and Administrator Goldin managed to play up the long-term cost savings of the LTV for commercial satellite deployment. He also managed to sell Clinton on the merits of Armstrong for strengthening ties to the Russian and European aerospace engineering industries, which played well to the Administration’s interest in cooperation with Russia. However, the sustainability of the Space Exploration Initiative would depend on the initial testing of the LTV and the preparations of Armstrong to remain on time.

    While administration officials debated the future of NASA’s manned missions beyond Low Earth Orbit, it was the agency’s most distant missions that were making the most tangible progress. The first Mariner Mark II mission since Magellan’s failure to reach the launch pad was Cassini, originally the Saturn Orbiter/Titan Probe. Launched on November 26, 1995 by a Lifter-Centaur rocket, Cassini was quickly injected on a Trans-Jovian orbit, picking up a slight gravity assist from that planet before continuing on to Saturn. After releasing its Saturn atmospheric probe, the spacecraft entered orbit around the ringed planet. Cassini then cut Huygens loose, sending the small, spin-stabilized probe on its own brief, independent journey to Titan.

    In the spirit of the Mariner Mark II design philosophy, and taking advantage of the budget increases NASA had seen under the Bush Administration for SEI, Cassini had received an additional atmospheric probe, whose design had been lifted with some slight modification from the Galileo Jupiter Probes that had performed so admirably almost two decades earlier. Fitting into one of the two attachment rings on the standard Mariner Mark II Bus (with Huygens operating the other ring), the Saturn Probe plunged into the planet’s mostly-hydrogen atmosphere on October 7, 2002. Though the two largest planets in the Solar System have a broadly similar chemical composition, Saturn is far lighter than Jupiter, and its gravitational pull is consequently weaker. The Probe entered the atmosphere at only 27 km/s, to the Galileo Probes’ 47 km/s, and as it fell through the Saturnian atmosphere, the pressures and temperatures it measured rose far more slowly than those encountered by its Jovian ancestors. Galileo’s probes had failed at roughly 23 atmospheres of pressure 55 minutes after their parachutes deployed. The Cassini probe, however, would take 55 minutes just to reach the 5 atmosphere depth required to succeed in its primary mission. There was a risk that Cassini would fall below the horizon, out of sight of its probe, while the probe futiley beamed its data out into space. The solution adopted at JPL was to simply cut the parachute loose after the probe slowed to terminal velocity, allowing it to fall through the desired depth while Cassini remained above the horizon. The scientists were not disappointed: the Cassini Probe survived to a pressure of 23.9 atmospheres before it ceased communications with the Orbiter, descending through almost a thousand kilometers of Saturn’s atmosphere, and the orbiter caught every bit of it.

    The Cassini Probe’s structure and Entry/Descent equipment drew heavily from that on the Galileo Probe, but its instruments were redesigned to tackle a new set of scientific questions. Planetary scientists disagreed on the actual way in which the Gas Giants had accreted, whether the heavy elements that formed the (presumed) core of the planets had been in the form of clathrate-hydrate asteroids and comets drawn into the cores, or whether they had been evenly mixed into the material that eventually formed the atmospheres of Jupiter and Saturn. To constrain models of planetary formation, scientists wanted data on the abundances of the “heavy” (heavier than helium) elements, namely oxygen, sulfur, phosphorus, and nitrogen. The Voyager and Galileo spacecraft had already shown that carbon grew more abundant further out from Jupiter, but the abundances of other elements were much less well-understood. To address that issue, the Cassini Probe carried as its primary instrument a mass-spectrometer to characterize the abundances of the heavy elements, particularly in the deeper, better-mixed Saturnian atmosphere.

    Though the spectrometer was the main instrument on the Probe, it also carried an optical camera to help characterize cloud structures and wind behavior in Saturn’s atmosphere. While the environment grew too dark for useful photography before the end of the Probe’s mission, the early phase of the Probe’s descent saw the recovery of dozens of photos of Saturn’s cloud-tops, and one particularly impressive photo of white-yellow clouds under a pale blue sky, with Saturn’s rings setting into the distant horizon. These were the first photographs returned from the Saturn system by the Cassini spacecraft, and they whet the appetite of scientists and the public for more.

    Huygens, a spacecraft built by the European Space Agency, occupied Cassini’s second attachment ring until its separation from the main spacecraft in June of 2002. For six months the probe drifted slowly away from Cassini, aimed at the thickly-veiled moon Titan. Last examined by the Voyager 1 spacecraft in the 1970s, Titan and its thick, nitrogen-and-hydrocarbon atmosphere held out the tantalizing possibility of a geologically and chemically active world, a world analogous to Earth, with seas of ethane and snows of tar. The engineers who designed Huygens half expected the spacecraft to splash down into an ethane sea, and designed the probe accordingly to float if it did.

    As it happened, the probe’s descent did not take it into a Titanian sea, but it did reach the next-best thing: a dry riverbed, resembling for all the world an Arabian Wadi. As the probe descended through the atmosphere, barely falling at all in Titan’s low gravity and thick atmosphere, its cameras sent back pictures of a narrow, steep-sided valley stretching from horizon to horizon. The probe’s slow descent through Titan’s atmosphere took 2 hours and 30 minutes, at the end of which it had very little battery power with which to actually study Titan’s surface, but the brief readings it did transmit to Cassini (which crossed under the horizon sooner than it might have, as the banks of the Wadi al-Huygens rose many meters above the icy sand on which Huygens actually landed) revealed a surface mostly composed of water-ice, with a thin slick of methane and methane-ice. Boulders of water-ice were strewn liberally across the Wadi’s bed, often dwarfing Huygens itself, indicating that the Wadi had been the site of a cataclysmic flood akin to the flash floods that often take place in Arabian and American deserts during rare thunderstorms.

    Huygens had been specifically aimed at Titan’s equatorial-to-temperate latitudes (between 60 N and 60 S). As it happened, Cassini’s on-board radar revealed, during subsequent close approaches to Titan, that the moon’s filled seas and lakes were mostly above 70 degrees north, with a few scattered around the South Pole as well. Though Huygens had missed landing in an actual body of liquid, the images it sent back of the Wadi al-Huygens were, if anything, more useful to characterizing Titan’s “methanosphere” than an actual splash-down would have been. Combined with studies of Titan’s atmosphere and repeated close approaches by Cassini, the results from Huygens helped planetary scientists to understand that Titan’s methane cycle operates on much longer time-scales than Earth’s water cycle does, with cataclysmic flash-floods of methane separated by decades of drought.

    Cassini itself went on to a productive primary mission after both its probes were expended. Powered by a plutonium RTG, the spacecraft made repeated close approaches to Titan and other moons of Saturn (particularly Enceladus, whose polar water geysers inspired even more hope for a sudden, monumental breakthrough than Titan’s strange, non-polar chemistry), and observed the planet Saturn and its magnetosphere. The planet’s relatively benign radiation belts and gentle magnetic field were an interesting contrast to vicious, dynamic Jupiter, and Cassini’s data on these phenomena and Saturn’s atmospheric behavior over the course of the spacecraft’s life helped develop and refine models of the behavior of giant planets, models which would soon gain another point when the Le Verrier mission reached Neptune.

    The most unique planetary science mission of the first decade of the new millennium, however, was not revolutionary in its propulsion technology or its instruments, but in the identity of its organizers. In 1994, as Geostar prepared to expand its network’s coverage to Europe and the former Warsaw Pact, one of the Geostar II satellite busses (Geostar IIC), suffered major damage in manufacturing when it fell from the truck bed on which it was being transported. Though the company partially repaired the bus, insurers were unwilling to cover the satellite on future launches, leaving a very expensive lump of aluminum, electronics, and solar panels sitting in a sealed nitrogen tank at the Geostar assembly plant in San Jose. The bus was set to be scrapped when, in 1995, the Space Studies Institute unexpectedly purchased it (at scrap-metal prices). The SSI had previously funded the development of advanced space technologies (in particular, it helped pave the way for the integration of Soviet Hall-effect thrusters into the Geostar II series, and sent numerous space manufacturing experiments up to Spacelab and Mir), but the SSI’s plans for Geostar IIC were more ambitious than anything it had done before. Though microgravity manufacturing of metals and crystals still attracted a great deal of scientific interest, investors in the 1980s and early 1990s had still been lukewarm to the idea. The SSI, directed by its late founder, Gerard K. O’Neill, to keep working “until people are living and working in space,” began to search for an alternate “killer application” to catalyze the movement of people and industry beyond Earth’s atmosphere. As launch costs in the 1990s began to fall again, due first to competition from the former Soviet Union and then to the emergence of more reusable launch systems, the idea of asteroid mining, long a fixture in science fiction, came back into vogue.

    The arguments in favor of asteroid mining are well-known: of the multitudes of minor planets in the solar system, some orbit close enough to Earth that the cost of propellant to access them is less than that needed to land on the Moon. Of those, some have useful resources that can be processed and returned to cislunar space or, more optimistically, Earth itself. A metallic asteroid can contain precious metals, which could be returned to Earth, and more mundane ones, which could be used in space. A carbonaceous asteroid or a comet could contain volatile ices, which could be refined into rocket propellant or plastics or other materials. However, there were in the early 1990s (and remain to this day) many unknowns about how exactly one could extract useful materials in the absence of gravity or a useful atmosphere. Serious planning for asteroid mining could not begin until basic questions about metallic asteroid morphology and chemical distribution were answered.

    It is those questions that the Space Studies Institute set out to answer when it bought the Geostar IIC bus and rechristened it Flying Mountain 1. Under the direction of Principal Investigator John S. Lewis of the University of Arizona, the bus was outfitted with an array of spectrometers, a microwave antenna, a radar antenna, and a high-gain communications dish. A high-resolution optical telescope, purchased from the Ameriglobe corporation (which used similar telescopes for their commercial imaging satellites), completed the set in 1999. Flying Mountain 1 spent the next three years awaiting a launch opportunity that would allow it to rendezvous with its target, the asteroid 1986 DA. This asteroid had attained brief notoriety in 1991, when radar observations showed it to be unusually smooth and reflective, supporting the hypothesis that it was a fraction of a differentiated body, spun off in a catastrophic collision--in other words, a fraction of a minor planet’s core. The prevailing theory of planetary formation holds that iron cores contained the bulk of the gold, platinum, iridium, and other comparatively rare metals that went into a planet during accretion, as these so-called “siderophilic” elements bonded easily to iron, which sinks underneath silicate. Popular science magazines thus briefly carried a headline about an asteroid that carried “10,000 tons of gold and 100,000 tons of platinum”--1986 DA. Flying Mountain 1, launched in 2002, set out to prospect the asteroid and see whether it could finally provide the “killer application” for spaceflight.

    However much public imagination was fired by the achievements of NASA and even non-governmental agencies in the push for renewed exploration of the outer reaches of the solar systems, the critical decisions about about the direction of American efforts in spaceflight under the new administration would depend more on the successes and failures of the manned spaceflight program--as the saying went: “No Buck Rogers, No Bucks.” While NASA awaited the new President’s decision on the fate of the SEI’s programs, they did their best to push on in spite of the uncertainties. Their major development projects, Armstrong and the Lunar Transfer Vehicle, were both in stages of development where progress was rapid, but largely unseen. The spring of 1993 found both projects rapidly moving through design reviews as parts began to pass out of design software and simulations and into the hands of manufacturing and test engineers.

    As the portion of the program most immediately tied to human spaceflight, the new Armstrong Partial Gravity Laboratory seized much of the spotlight, with the Lunar Transfer Vehicle trailing along in its shadow for lack of a decisive plan for what activities it would be enabling in lunar orbit beyond extended versions of the Apollo 8 mission. Armstrong’s mass ultimately came to slightly over 40 tonnes, mostly concentrated in the Equipment and Service Module (which, during launch, held a great deal of the equipment that would be used to outfit the Wet Workshop). This weight precluded the launch of a crew with the station, as had been done on STS-100, and necessitated a second flight for checkout and setup of the space station, leading to a phenomenon unseen since the Gemini program: two NASA launches from Cape Canaveral in the same day. The launch of Armstrong went off flawlessly on October 9, 1995 with the launch of STS-238 by the Space Lifter Liberty, followed just hours later by the launch of the Space Shuttle Destiny on STS-239 aboard the Space LIfter Independence, which docked with the Shuttle in the early morning of October 10. Over the course of a three-week mission, the crew of Destiny transferred equipment from the ESM to the Wet Workshop, bringing that space to a much greater degree of utility than the Wetlab workshop had ever achieved. They also transferred from their MPEM a number of furnishings and instruments which could not fit inside the ESM during launch, filled as it was with Wet Workshop equipment.

    Before undocking on Mission Day 14, the crew of Destiny spun the space station up to 3.5 rotations per minute, enabling the ‘lowest’ level of the Wet Workshop to experience approximately 30% of Earth’s gravity at its floor, while the upper levels experienced progressively smaller accelerations until acceleration was virtually zero at the Docking Module. The ESM, on the opposite side, experienced an acceleration equivalent to that on the Moon’s surface.

    The need to keep the station spinning to simulate low gravity complicated both its design and operations involving it, and played a role in delaying the debut of European Crew Return Vehicle originally designed for a permanent docking at Spacelab. As the station drew its power from the sun (whether through photovoltaic conversion or dynamic conversion), it needed to track the sun over the course of its orbit around the Earth, and the Earth’s own orbit around the sun. While a fairly straightforward problem on a microgravity platform, it was complicated by the station’s rapid rotation, which forced the panels to stick out from the end of the ESM, parallel to the spin axis and mounted on bearings that themselves spun at 3.5 rotations per minute to counteract the station’s rotation. A great deal of work had been done on the ground to ensure that these bearings would have a long lifetime, but their replacement still constituted the single most frequent reason for EVAs during Armstrong’s lifetime. The problem of thermal control of a spinning station was similarly difficult. The fact that the station appeared to be spinning whether one spun with it or not led to a number of comparisons by observers on the ground, from windmills to the throne of God, described by Ezekiel as containing wheels within wheels.

    While the Space Shuttle had been designed with some ability to grapple and dock with spinning objects, the ability had seldom been used, as the most frequent targets for Shuttle docking missions (Spacelab, Hubble, and USAF reconnaissance satellites) generally were despun to simplify the maneuver. Such operations with spinning spacecraft required precise control of the vehicle’s center-of-mass. When the crew of Destiny undocked from Armstrong, one of their first tasks was to fly out to a distance of 100 meters, de-spin their craft, then re-spin and re-dock, in order to prove the feat was possible at all. A number of accelerometers aboard Destiny fed information into the Shuttle’s docking computer, confirming that the vehicle’s center-of-mass was close enough to the docking axis to enable it to spin properly about that axis. Once de-spun and re-spun, Destiny, under the control of her pilot, Eileen Collins, carefully navigated back to the station. The procedure was repeated a number of times under different lighting conditions and with a number of Armstrong’s tracking features (lights and radio beacons) disabled, but ultimately, all the tests were successful, and the space station was formally open for business by October 26, 1995.

    Destiny departed Armstrong and made a brief, 4-kilometer flight to Spacelab, where her crew performed routine maintenance on experiments aboard the station and collected samples for analysis on the ground. In the future, such missions would be delegated to the European CRV, which was evolving from an emergency return vehicle into a more generic, more capable vehicle. Though three Block I CRVs had been manufactured (under the original program name, “Asclepius”), focus had quickly shifted to Bock II, dubbed “Hermes,” which would take over the role of return vehicle, inter-station transfer vehicle, and, ultimately, translunar crew capsule.

    The Block II eCRV, with an uprated heatshield capable of returning from a translunar trajectory and improved life-support hardware for its long sojourns to lunar orbit, enjoyed a great deal of commonality with the Block I prototype. While the spacecraft carried more lithium hydroxide (for atmospheric filtration) and more storage space allocated to mission consumables, its outer mold line was essentially identical to that of the Block I capsule, and most of its reentry hardware was only slightly modified. The Service Module was now worthy of the title--rather than a mere array of retrorockets, it was now a modified communications satellite bus that enabled the eCRV to maneuver between Armstrong and Spacelab, and to control the finer aspects of its trajectory during final approach to Earth on high-speed translunar reentries. The spacecraft was put through its paces from 1994 to 1995 in ground tests and in one unmanned orbital test flight, during which an Ariane 3 launched a Block II eCRV on a three-orbit mission to verify its thermal control, power generation, and communications systems, and to demonstrate the capability of ESA and Australian personnel to recover the spacecraft.

    The eCRV would finally arrive at Armstrong several months after Destiny’s crew first checked out and completed the station. Launched on an Ariane 3 in March of 1996, the first operational Block II eCRV took up residence at one of Armstrong’s two axial docking ports, leaving the other free for visiting Space Shuttles. In April, the first long-term Armstrong crew, composed of the astronauts Sharon Lucid, Jerry Linenger, and the German Reinhold Ewald, with Russian cosmonaut Vasili Tsibliyev (the first Russian to launch aboard an American rocket), began their six-month stay aboard the station, during which they would conduct groundbreaking experiments in partial-gravity medicine and biochemistry and service experiments aboard Spacelab three times. The eCRV completed its manned shakedown tests with flying colors. Together with the unmanned eCRV reentry test in 1995, the Armstrong 1 mission certified the eCRV for its coming missions beyond Low Earth Orbit.

    As for the LTV that would carry it there, its engineers wrapped up the major design work on the new spacecraft and prepared for production. In order to provide for the two or more tug pairs estimated to be required for a lunar mission, NASA had placed an order for six flight-rated tugs, plus ground testing components and flight spares. By the spring of 1993, the design of more than 50% of the stage’s major components had been frozen, among them the critical dimensions of the stage’s methane and oxygen tanks. With this complete, the tooling for rolling sheet metal barrels, spinning the tank end domes, and welding them all together was being put into development. While automated techniques were being considered for future McDonnell projects, the LTV’s tank production would have more in common with their older cousins, as the cost of automation wasn’t judged worth it given the short production run. Testing was also underway with NASA assistance on the development of the forward niobium-alloy heatshield, testing the ability of sample segments to resist the planned aerobraking profile’s blowtorch environment both with and without the intended methane coolant system, ensuring that even a failure of the cooling system would allow the return of the stage to LEO for retrieval. The inconel flare and sidewall insulation shielding were subjected to their own tests, though less severe as the forward main heat shield would take the brunt of the heat loads. All passed, though not without revisions. Functional prototypes of the transfer couplings to allow propellant to be moved into an LTV from a tanker or from another LTV were added to NASA’s Six Degrees of Freedom test rig in Houston, checking that the couplings would not interfere with docking but could be successfully and reliably locked after docking, and more importantly released after use without leaks. The radar systems were tested in parallel with Shuttle’s own radar on flights to Spacelab, and a robotic test system was temporarily mounted to the station to test repeated use of the propellant transfer couplings in space. Slowly but surely, the LTV began to come together, first as drawings and mockups, then as boilerplates and sample parts, and finally as a vehicle ready for space.

    The LTV’s structure wasn’t the only system to pace its progress, however. While Aerojet’s design of the small gas/gas CH4/LOX thrusters was proceeding on schedule with initial tests of ignition transients and spark igniters, the Lunar Tug Main Engine (LTME) from Pratt and Whitney was proving more of an issue. Pratt had confidently banked on their RL-10 experience and the small size of the LTME to make a transition of their expander cycle to methane operations trivial. Instead, the opposite was proving true. Thermodynamically, the lower heat capacity of methane meant less cooling capacity and pump energy was available for the same mass of coolant, while the small size of the chamber proved as much of a challenge as a benefit. The tiny chamber, described by some engineers as a “fireball in a paint can,” was so small that even minor intrusions like the walls’ brazing or the locations of temperature and pressure probes caused variations in the internal flows and the rejection of heat into the cooling jacket. Meanwhile, the requirement for >99% reliability in ignition and combustion over a design lifetime dozens of times longer than any engine other than the Lifter’s F-1B--and with less maintenance--were a major issue for testing, even if the expander cycle and methane’s low-coking properties made the LTME inherently more reusable than the massive F-1B. Still, the first components of the LTME were being fabricated and tested on lab benches, with a full-scale engine scheduled for firing by the end of the year. From there, it was anticipated that more than a year and a half of qualification firings and tests might be required, running concurrent with the production of the 30 engines required for flight operations in 1994 and 1995. The LTME posed a risk that significant further delays could postpone the start of flight testing, or require early test flights of the LTV without fully-qualified engines. Under pressure from NASA and McDonnell, Pratt buckled down to work.

    In the meantime, NASA reviewed their options for communicating with the LTV on lunar trajectories. In the Apollo program, NASA had been forced to build a global network of ground stations from scratch to communicate with the Apollo crews as the Earth rotated beneath their trajectory to the moon. Even so, they had been unreachable when they were behind the moon, leading to extended period where the crew was unable to communicate with Earth. The role of the ground stations for providing continuous coverage had been taken over by the TDRSS launched by the Space Transportation System, ensuring that astronauts anywhere in cislunar space visible from Earth would be in contact at all times with mission controllers back on the ground.

    However, with the communications downlink requirements of Spacelab, Armstrong, the Space Shuttle, and lunar LTV flights possibly someday including crew, the Space Exploration Initiative would require more than TDRSS could currently offer in terms of bandwidth and redundancy. Moreover, the communications blackouts on the lunar farside could no longer be tolerated: the “dark side of the moon” could no longer be under communications shadow. Thus, portions of the funding from SEI would go to a refreshed generation of TDRSS satellites able to handle more sources in orbit at once, and able to supply higher data throughput both between these sources and the ground and between the sources themselves, making use of advances in onboard switching implemented originally by commercial low-Earth-orbit development. More to the point, not all of this new generation would be placed into geostationary orbit. Instead, the new geostationary orbit birds would be joined by duplicate satellites placed into halo orbits of Lagrange Point 2 on the lunar farside, relaying from vehicles in lunar orbit and on the surface to the existing geostationary portions of TDRSS.

    Much like Shuttle and Lifter had launched TDRSS, the LTV would have the responsibility of establishing the network which it would come to rely on: some of the first operational missions of the Lunar Transfer Vehicle to cislunar space in 1997 would carry next-generation TDRSS satellites to deploy to L-2. For its earliest flights to the moon, the LTV would have to be capable of operating beyond Earth’s control for critical operations, but if it proved as successful as the Space Transportation System before it, it would soon establish the infrastructure necessary for extensive manned and unmanned operations around the moon.

    If NASA was fueling a revolution in communicating with spacecraft in orbit, Trans-Pacific Launch Industries and the Space Transportation Corporation were starting to fuel one in low Earth orbit. For years, geostationary communications satellites had become an accepted and critical link in the transmission of a wide variety of communications media, from relaying satellite telephone interchanges to the distribution of satellite television. Geostar had even demonstrated its use for limited messaging in a two-way perspective for short customer messages, the status symbol of the global road warrior one step up in cost, capability, and prestige from the more common beeper. However, efforts to do other end-user communications applications from the stable platform of geostationary orbit all ran into one hard truth, the same one Admiral Grace Hopper had to teach to the Department of Defense in her era, which now had to be explained to many executives of communications companies: light could only travel so far in a millisecond, and there were a lot of those distances on the way to and from a geostationary relay satellite. The pauses of satellite relays were a common feature on new 24-hour news networks as they tied in reporters around the globe, and plagued executives trying to use international calling over satellite relays as well. To reach the masses, satellite would have to descend from their heights to the depths of low Earth orbit.

    To manage this feat, the number of satellites and the variety of their orbital inclinations would be greatly increased to ensure constant relay around the globe. One satellite telephone network named itself Iridium after the 77 satellites they originally calculated to be necessary to reach their customer base, while some satellite internet providers estimated requiring more than ten times that many satellites to reach their initial operational status. The only benefit was that without the requirement to communicate all the way from geostationary orbit, the size of each individual satellite plummeted: dozens could fit in a launch of a TPLI Sierra, and the legacy Space Lifter could launch near triple digits of many of the designs, populating entire orbital planes in a single flight. Without this capacity and the low costs of the associated vehicles, the LEO comsat boom would never have been able to dream of getting off the ground. As it was, Iridium, one of the earliest and less technological aggressive of the concepts, signed a contract with TPLI to launch large portions of their initial orbital capacity in 1997. With one technical venture with high investment risk contracting to fly on another, some industry observers exchanged quiet bets over email and IRC if both could stay funded long enough.

    Iridium wasn’t the only player to invest in Low Orbit communications. After the US military’s Global Positioning System became fully operational in the early 1990s, GeoStar took stock of its options and found that, while navigation had been one of their selling points in the 1980s, long-distance communication was actually the greatest service they provided. Furthermore, the rise of the internet suggested that there would soon be a market for high-bandwidth data not just in the developed world, but in the developing world. A GeoStar PowerPoint presentation from 1995 does not hide the scope of their ambitions: by proposing a global internet constellation, they proposed to tie billions of new consumers into the exploding e-commerce market. The next slide goes on to note that there were no high-speed cables in large parts of Africa, South America, and Asia--effectively meaning that the first company to beam internet from Low Earth Orbit would have a monopoly on entire continents.

    The GeoStar Arachne series of satellite busses was born from these considerations. Far smaller than the great geostationary busses they’d launched before, and produced by the truckload, each weighed just a few hundred kilograms. The only serious problem the series encountered during its development was the sheer speed at which internet speeds increased, which drove redesigns to the communications gear to process ever-greater transmission rates. Ultimately, though, GeoStar settled on a bandwidth that they felt could transmit every service of value (modest by modern standards, in the days before high-definition streaming), and Arachne began launching aboard TPLI’s Sierra in 1999.

    While the development work to prepare Armstrong, the LTV, and the eCRV was underway and NASA plumbed ever deeper into the solar system in the wake of the loss of Magellan, the future of the space program was being decided elsewhere. In PowerPoint presentations in boardrooms in Silicon Valley, the comsat business was hunting for the funding for the constellations which TPLI and STC hoped might fuel the next boom in reusable launch systems. Meanwhile, in briefings between President Clinton, his advisors, Administrator Goldin, and key congressional powerbrokers, the fate of human spaceflight using the Lunar Transfer Vehicle to fly to the moon was hotly debated. The most valuable data on the future of spaceflight flowed into offices in Washington D.C., where the fate of the Space Exploration Initiative’s follow-ups would be decided by bean-counters and politicians who would never once design a combustion chamber or feel for themselves the pressure of preparing and flying a mission to space.
     
    Chapter 17: Approach
  • So due to a severe oversight on my part, I posted next week's chapter this week and didn't notice the mistake until e of pi pointed it out to me...:oops:...Well, lucky you guys! You get two chapters this week!

    “On Apollo 8, we were so close. Just 60 nautical miles down, and it was as if I could just step out, and walk on the face of it.”​

    Chapter 17: Approach

    Constitution soared down the Florida coast, tracing the beaches, guided by radio signals from Kennedy Space Center. Strictly speaking, the guidance was not needed--two veteran naval aviators like Young and Crippen could have navigated along that familiar coast in their sleep--but why fly without it?

    The spacecraft had by this point completed her metamorphosis into a colossal aircraft. Her rocket propellant tanks were almost entirely empty. Only a small slick of kerosene remained on one wall of the RP-1 tank. The LOX tank had already been vented into the atmosphere. Her F-1Bs were silent and would not light up again on this flight. Safely hidden from the incoming air stream by protective fairings, they had little influence on her aerodynamics. Her ten F-110 jet engines provided all of her propulsion now, burning a separate supply of JP-8 jet fuel, running at a fairly low throttle. Her peroxide thrusters were almost useless in the thick troposphere, and instead she relied on her vast sail-like control surfaces, whose internal hydraulic rigging kept her course steady and mostly level. She was now moving at a subsonic, but still respectable, pace, matching that of any airliner.

    She still handled sluggishly. Her pedigree was a spotty one, for rockets, ultimately, are a form of artillery, not aircraft. Her family’s rebirth as rocket-propelled aircraft was a matter of cost optimization, not of performance optimization, and it showed in her maneuverability, or rather, lack thereof. The task of bringing
    Constitution to a safe landing had far more in common with that of landing a Boeing 747 than a fighter jet.

    The craft was immense, but mostly empty. Her sail area was large, her inertia small. She responded with sudden jolts to any unexpected turbulence. Young and Crippen held her steady with hands honed in conditions far tougher. They had no time, busy as they were with the constant checking and re-checking of the aircraft’s displays and dials, to reflect on the increasingly mundane character of her flight, as a ship capable of hypersonic flight at the very edge of space came to imitate her mundane cousins who plied the routes between airports.


    While briefing the President on the progress of the LTV and Armstrong throughout 1994, Goldin was quick to stress the strides which were ongoing in both programs. By the fall of 1994, the Lunar Transfer Main Engine’s combustion problems had been almost entirely resolved, and Pratt & Whitney were delivering completed engines to McDonnell-Douglas for integration. Meanwhile, IBM had delivered the radiation-hardened instrumentation units that would guide the new stages through the Earth’s radiation belts to their needle-threading dives into the atmosphere. At the same time, Armstrong’s Equipment and Service Module had arrived at the Kennedy Space Center’s Payload Processing Facility, where engineers conducted fit tests between it and the modified S-IVD that would serve as Armstrong’s annex. Both of the programs that President Bush had signed into law were nearing completion. With their milestones came a need to chart the course for the next phase of the Space Exploration Initiative: the one which would select from among the myriad of possible applications for the hardware the shape of human spaceflight for the next decade. A decision for which George Bush had laid groundwork now lay in the hands of his successor.

    The decision came as no particular shock to the White House: while stressing the progress of NASA’s projects, Administrator Goldin had repeatedly pointed out that the time had come for a new direction for spaceflight. He had also pointed out that the simplest, cheapest project to tie this elements together was that which had guided the original design of the LTV and the Hermes capsule. If unstated, the goal had always been manned lunar orbit and surface operations, as another president might have said, “before this decade is out.” While the hardware to access lunar orbit had been approved, no formal authorization had ever been made of an overarching architecture. With LTV on-track for a debut in late 1995, Goldin outlined the design studies NASA had done, but pointed out that the agency had not yet committed to the lander or a staging platform in lunar orbit. Goldin and Vice President Gore, between them, sold Clinton on the idea during 1994, and the program (dubbed the International Lunar Program, in recognition of the European, Japanese, and Russian contributions that helped make it possible and to avoid for the moment the challenge of finding a name that satisfied all parties) was officially funded for FY1995. Clinton’s motivations came down to a combination of politics and legacy; with the LTV to finish testing by the end of 1996, there was an incentive to throw funding toward the aerospace industry, particularly in the swing-state of Florida. As the economy recovered from the recession of the early 1990s, there was no serious opposition to the modest increase in spending necessary to develop the lander (whose hardware had a great deal in common with that of the LTVs) and its Low Lunar Orbit support station (essentially composed of spare parts from the existing LEO programs).

    Clinton’s other motivation for supporting the lunar surface program came down to an appeal to his legacy and that of John F. Kennedy, the earlier Democrat whom Clinton had met in 1963. Clinton publicly credited that meeting, together with Martin Luther King Jr.’s “I have a Dream” speech, for inspiring him to go into politics, and the youthful image he cultivated consciously imitated the martyred statesman (as, sneered many Republicans, did his personal indiscretions). The American manned space program had become one of the programs most closely tied to Kennedy’s name (as it had been one of the few that went into effect before his murder), and a generation of news of launches from “Cape Kennedy” or the “Kennedy Space Center” had only strengthened the association in the public eye. Even though the actual Moon landings had taken place under President Nixon, and most historians would argue that President Johnson played a far greater role in creating Apollo, the public still viewed the Moon landing as Kennedy’s triumph. With the Lunar Transfer Vehicle already in testing, Clinton could reasonably expect a lunar landing by 2000, while he was still in office (assuming a victory in the 1996 election), enabling him to similarly create a legacy in space. Whoever followed him into office would have astronauts on the Moon executing Clinton’s program.

    It was these considerations that led Clinton to announce, during his State of the Union address on January 24, 1995, "We are even now embarked on the path to the Moon. I have directed the National Air and Space Agency to continue down this road with a new lunar lander, building on the reusable legacy, not just to go to the moon, but to eventually stay."

    The lunar surface exploration program called for two new vehicles: a man-tended outpost in a lunar polar orbit, which would use surplus Armstrong and Shuttle hardware and provide station-keeping, light servicing, and propellant-transfer facilities for the second vehicle, the lunar lander. The lander far outclassed the Apollo Lunar Module--designed to be fueled and serviced by three two-stage LTV missions to Low Lunar Orbit, it would have a wet mass of more than 25 metric tons tonnes and could deliver 8.5 tonnes of payload to the lunar surface and back. The new lander would be fully reusable, returning to a Low Lunar Orbit platform for use on a later mission or return to Earth by an LTV and either the Shuttle or some successor vehicle (though, given the cost of such a return, that kind of operation would be done only rarely).

    The decision to develop a fully-reusable lander architecture with such an impressive payload capacity proves the truth of Mark Twain’s adage that “history doesn’t repeat itself but it often rhymes.” Though the official Apollo/Saturn program began winding down as early as 1967, when the development work for the space systems was virtually complete and a landing on the Moon (even if Kennedy’s deadline was missed) seemed a foregone conclusion, NASA’s official party line was that Apollo’s purpose was not limited to putting a man on the Moon. The Apollo and Saturn hardware, the agency insisted, would see ongoing use in earth-observing scientific missions, interplanetary robotic probes and human missions, missions to study solar physics, and ongoing missions to the Moon. Though the scope of the program was drastically cut back to support the development of the Space Lifter and Space Shuttle, the party line had, ultimately, mostly come true. Skylab had proven many of the concepts that would be required to develop Spacelab, Lifter-Centaur had lofted a multitude of unmanned probes that returned data on every element of the solar system and the greater universe, and the Shuttle had allowed the US and its European and Japanese allies to break new ground in microgravity science aboard Spacelab. Though NASA had turned its attention in the late 1970s toward using space rather than building the infrastructure to tap the unique possibilities beyond the Karman line, the Space Exploration Initiative marked a return to the old roadmap.

    In accordance with the goal of establishing a sustainable infrastructure with which to explore the Moon and open possibilities beyond, the lunar landing system had to be reusable while still delivering a significant amount of payload to the lunar surface. Though NASA did not plan to do this regularly, the option of returning the lander to Earth for inspection was preferred. For many reasons (including storability, development cost, and propellant density), methane was the preferred fuel. Satisfying all of these requirements in a single craft in a single flight proved unfeasible, but the lander’s reusability meant that the payload issue could be addressed by simply landing twice--once to deliver surface cargo, and then again with crew. Mission planners soon converged on a two-landing architecture, in which the lander would deploy a payload, return to a small Low Lunar Orbit Platform, refuel, and then deliver the crew to meet that payload. The entire lunar transportation architecture would thus be reusable, except for launch vehicle upper stages for flights carrying crew, cargo, and propellant to LEO, and for the lunar surface laboratories and equipment pallets, which would be left behind on the Moon after each mission, forming a gradually-expanding network of functioning habitats and scientific experiment arrays that could be reactivated and revisited at any later moment.

    Digging back to Apollo Applications Program designs for the Lunar Module Truck and Taxi, and to more recent design studies for lunar surface habitats and vehicles, engineers at the Johnson Space Center converged on two possible target payloads--11.5 tonnes (which would require two LTV supply flights per landing) and 21 tonnes (which would require three). The spacecraft that would carry those payloads down would be a 4.5-tonne (dry) assembly of propellant tanks and landing legs wrapped around a single, throttleable LTME. With the spacecraft’s design converged upon, the last serious debate as JSC was exactly how capable it should be. 11.5 tonnes of payload per crewed mission was enough for up to a week, maybe two, of human exploration, whereas 21 tonnes opened up the possibility for month-long (or even longer) flights. More conservative engineers favored the smaller design, believing it to be easier to develop, cheaper to operate, and an easier sale to the politicians who ultimately controlled NASA’s budget. Opposing them was a faction committed to the idea of LSAV as a heavy cargo carrier that would open the Moon to American interests as effectively as Lifter had opened LEO and GEO. Pointing to the earlier vehicle’s success, they noted that Lifter’s immense capacity, while greater than many of its payloads really needed, had given NASA the capability to conduct those few great missions that could make full use of its power, like Spacelab, the unmanned probes to the outer planets, and the Shuttle missions. That capability had allowed Lifter to operate for nearly twenty years, to the point where its immense lift capacity had become the cornerstone of NASA’s and McDonnell-Douglas’s plans to refuel and operate the LTVs. “Build it, and they will come,” went the thinking. “In the void of space,” argued one engineer at a team meeting in Houston, “vehicles are infrastructure, and we’re building the Interstate to the Moon.”

    The more ambitious faction eventually won out at JSC, and it was their design, a lander with a wet mass of 46 tonnes, of which up to 21 tonnes was payload to the lunar surface, that went to President Clinton’s desk. Following a briefing from NASA Administrator Dan Goldin, Clinton gave his formal blessing to the 46-tonne Lunar Surface Access Vehicle, which would become the most visible vehicle of the Space Exploration Initiative.

    As it turned out, the decision to adopt a high-payload lander design would impact the entire world’s aerospace industry. The lunar surface exploration program outlined in 1995 (which would become known as the International Lunar Program) called for two lunar surface missions per year. These missions would each require three flights of a two-stage LTV, which added up to an initial mass in Low Earth Orbit (IMLEO) of over 250 tonnes per mission! Given that at least one Lifter flight per lunar mission had to loft the Shuttle containing the crew for that mission, the program would require over a dozen Lifter flights per year on its own. Between the ILP, crew rotation missions to Armstrong, and Lifter’s existing unmanned payload manifest, the Space Transportation System would have been taxed to its limits (and with the Lifters growing long in the tooth after over 15 years of frequent service, neither Boeing nor the Space Transportation Corporation wanted to push their luck with a ramped-up flight rate). The Commercial Propellant Supply Services contract, which had originated as an effort to secure redundancy for LTV propellant supplies, had gone from a luxury to a necessity, as alternative launchers were needed to supplement the Space Transportation System.

    Of the alternative launchers available in 1995, only the Russian Raskat-Groza system and the TPLI Sierra (still in testing) had the capacity to supplement Lifter. Ariane was too small, and the European Space Agency’s launch complex in French Guiana was not optimized for the frequent flights it would need to make up for that shortcoming. The Clinton Administration and NASA quickly found a silver lining in the cloud of limited launch capacity: as Russia’s economic and geopolitical situation deteriorated and the structural failures of the Soviet Union grew ever more apparent (with an HIV/AIDS epidemic that dwarfed that which had terrified Reagan’s America, and the emergence of sinister new narcotics in a booming Russian market), a launch services contract to NPO Energiya seemed, to the State Department, more an instrument of humanitarian relief than a frivolous expenditure. Every light that stayed on in Moscow, Baikonur, and Kazan was a household that had not turned to prostitution or Krokodil to avoid starvation.

    Two Commercial Propellant Supply Services contracts were awarded in 1996, each for 800 tonnes of propellant delivered to Lunar Transfer Vehicles between 1997 and 2002, to NPO-Energiya and Trans-Pacific Launch Industries. Though this amounted to only about four flights per year of Raskat-Groza and six to seven per year of Sierra, it was a significant boost to the Russian annual flight rate, and helped speed along the Russification of the Raskat boosters, a process which accelerated significantly when Russia’s new Prime Minister, Vladimir Putin, took power. It was also a massive boon to TPLI: coming swiftly on the heels of Sierra’s first successful orbital test flight, it greatly increased customer confidence in the new consortium, and initiated a rapid expansion of TPLI’s customer base from a handful of low-orbiting communications constellations to a much more diverse set of payloads and destinations.

    Though the ground on which the new spacecraft tread (literally, in the lander’s case) was now far better known than it had been in the 1960s, the development of the new spacecraft was still an impressive and lucrative contract for which the American aerospace industry’s remaining prime contractors marshalled their formidable resources. The sharp contraction of the American aerospace industry since 1991 reduced the total number of bids, but each of the surviving companies combined the best talent from their acquisitions, leading to a bidding process as heated as any before it.

    Ultimately, NASA awarded the Low Lunar Orbit Platform (LLOP) contract to a joint bid from Grumman Aerospace and Hughes Satellite Systems, a choice that seems surprising (between Grumman’s near-insolvency and Hughes’ inexperience with manned systems) until one considers the LLOP’s unique mission. Unlike Spacelab or Armstrong, the LLOP was not a laboratory or a full-time human habitat. Its power and thermal requirements were considerably less demanding than those of the Low Earth Orbit space stations, and were well within the capabilities of Hughes’ communication satellites. The pressurized part of the LLOP was heavily derived from Grumman’s MPEM (though it did not share a pressure vessel, as the requirement for a radial docking port precluded that possibility), and most of the subsystems could be reused from that with minimal modification. Hughes and Grumman, while not the largest competitors, were the smartest choices in 1996. The sale of Grumman Space Systems to Martin Marietta did not change that reality (and caused very little disruption to the program).

    Though LLOP was a welcome victory for Grumman and Hughes, it was not the main prize in 1995. The Lunar Surface Access Vehicle (LSAV), the gargantuan reusable lunar lander, was the more prestigious of the two projects. Though its propulsion systems had already been specified to use the same methane-oxygen systems developed for the LTV (including the Lunar Transfer Main Engine), the structure, avionics, thermal and power systems, and final assembly remained up for grabs. Though Grumman and Hughes made a bid for the lander as well, it was a far greater task than LLOP, and the small consortium was never really in the running. Rather, the contract soon came down to a three-way race between Boeing, McDonnell-Douglas, and Martin Marietta. Each company had its own strengths and weaknesses--Boeing had the strongest record in actual spacecraft construction, though McDonnell-Douglas had gained some ground in that field with the LTV program and would have had the least difficulty integrating the propulsion system, and Martin-Marietta was the undisputed world leader in autonomous vertical landing technology. The competition to secure the LSAV contract was a tight one indeed, and the budding space news sector on the internet swarmed with contradictory rumors for months leading up to the final announcement. Ultimately, in a surprise coup, Martin-Marietta secured the contract, as the company’s proposal was highly rated on both its organizational and technical strengths. Based on some hardware from the Fuji upper stage, the LSAV’s landing systems would be very closely derived from the vertical-landing hardware and software that Martin-Marietta had been perfecting since the 1980s. Though the propulsion system would remain a McDonnell-Douglas subcontract, Martin-Marietta’s interest in perfecting low-boil-off (LBO) and zero-boil-off (ZBO) LH2 storage hinted at the possibility of a future generation lander that would use cryogenic hydrogen to massively increase payload to the Moon.

    The LSAV contract could not come swiftly enough for Martin-Marietta, which was still struggling in the aftereffects of the Japanese asset bubble on their Trans-Pacific Launch Industries partnership with Mitsubishi and the Japanese government. Martin-Marietta’s fortunes recovered somewhat as the general American economy recovered from the recession of 1991, but increasingly Sierra became a make-or-break project for the company. Its continued survival would stand or fall on TPLI’s successful entry into the commercial launch market.

    In many respects, the LSAV contract marked the last great hurrah for the traditional aerospace contractors of the US. While the contract itself was small compared to the great defense contracts that had filled their coffers during the Cold War, it was the last time that these companies, some of which had been independent since before the Second World War, could make a bid to be prime contractors on a new aerospace vehicle. Following McDonnell-Douglas’s and Pratt & Whitney’s success, the strains of Peace Dividend budget cuts combined with overseas competition and, in some cases, poor management decisions finally caught up to many of their competitors, initiating a rapid succession of mergers, consolidations, and divestments that would leave the American aerospace sector in the hands of a much smaller number of prime contractors.

    The process had already begun in the early 1970s, with the cancellation of the Lockheed 1011 TriStar jet airliner program. Long-delayed due to engine availability issues, it was finally scrapped when the interested airlines committed instead to Douglas’s DC-10 (known as the MD-10 in later production runs, after the merger with McDonnell), and Lockheed permanently dropped out of the civil airliner market, which, in the US, was split between Boeing and McDonnell-Douglas. Lockheed refocused on military aircraft, perfecting cutting-edge stealth technology, which made its debut in the form of the F-117 Nighthawk. Lockheed followed up its success with the B-2 Ghost, an even stealthier high-altitude bomber design, becoming the undisputed world leader in stealth technology. Alas, with the cancellation of most B-2 orders following the Soviet Union’s demise, Lockheed could not soldier on alone, and was bought out by its old airliner rival, McDonnell-Douglas, which attempted to leverage its own supremacy in naval aviation with Lockheed’s stealth technology for the A-12 Avenger II project (which, unfortunately for the conglomerate, went nowhere).

    Lockheed was not the only company swallowed by McDonnell-Douglas. Grumman Aerospace had once enjoyed the confidence of the US Navy’s top admirals and of NASA’s astronauts, and its engineers had blazed many new trails that other companies would profitably exploit. However, from the early 1980s, the aeronautical section of the company had increasingly been deemphasized, as managers gave up hope of winning new prime contracts. Electronic subsystems instead were emphasized, as the company adapted to the new age of electronic warfare. It was this section of the company that would eventually be purchased by McDonnell-Douglas in 1997, leaving Grumman Space Systems to soldier on a very short while longer before it, and all its R&D contracts, and the MPEM (its last prime contract from NASA) were acquired by Martin-Marietta.

    Northrop Corporation was badly burned by a series of ill-fated partnerships in the 1970s and 1980s, which left the company with a great deal of patents and research it could leverage for future planes but no actual prime contract to provide income. The partnership with McDonnell-Douglas had given the latter the F/A-18 Hornet carrier-based fighter, and was supposed to give Northrop an F-18L to sell on the export market. However, McDonnell-Douglas began selling an export-variant of the F/A-18, cutting Northrop out of the market and securing all the profit on Northrop’s significant research investment (going back to the YF-17). Soured on working with McDonnell-Douglas, Northrop instead partnered with Boeing to bid on the aircraft that eventually became the B-2 Spirit. While Northrop’s approach was, in many respects, more innovative and capable than Lockheed’s, the company’s pure flying-wing proposal would not win that competition. Boeing fell back on its bomber, airliner, and spacecraft businesses, but Northrop did not have this option. The company would eventually be bought by Martin-Marietta for a very low price, in a deal brokered by the US Department of Commerce and Department of Defense to prevent McDonnell-Douglas from getting an undisputed monopoly on stealth technology, and as part of an effort by Martin-Marietta to maintain any business outside of their launch services division.

    Martin-Marietta, by the 1990s, had become almost entirely focused on rocket technology. Through its work on vertical-landing demonstrators for the US Department of Defense and its partnership with Mitsubishi in TPLI, it had made great strides in perfecting reusable, ballistic vehicles. It was also one of the US’s premier ICBM manufacturers, involved in the LGM-118 Peacekeeper and the MGM-134 “Midgetman” missile programs. Unfortunately, the end of the USSR marked a drastic reduction in funding for new missiles--the MGM-134 program was cancelled in 1991, after only one prototype missile was built and tested in 1989. The cancellation left Martin-Marietta an extremely narrowly-focused company--one whose main business had become civil space transport. It could continue to fund the development of Sierra through infusions of cash from investors (including its partner, Mitsubishi Heavy Industries), but its investors worried about the possibility of the entire company going under if Sierra and TPLI proved a bust. When Northrop became available at a fantastically low price, Martin-Marietta’s board jumped at the possibility of entering what had been the lucrative military aviation market. As it turned out, the merger essentially produced two parallel firms under a single name, and the fortunes of one did not severely impact the fortunes of the other.

    By early 1995, Sierra’s development work had been completed. The first stage had completed its first trial firings and demonstration flights in Japan, under the authority of Mitsubishi Heavy Industry the year before. Meanwhile, the first Martin-built Fuji orbiter stage was transferred to the White Sands Missile Test Range for the integrated vehicle’s first shakedown flights. Flying first with partial fuel loads on only its LE-5 landing engines, then with increasing propellant loads and payload mass simulators, Martin put Fuji through its paces, demonstrating the vertical landing techniques Martin-Marietta had first demonstrated in the 1980s. At the first and second stage test sites and the launch-sites-to-be in Japan and the United States, TPLI’s launch technicians trained for all possible pre-launch eventualities. After successfully completing its suborbital flight test program, the first flight Fuji stage was shipped to Vandenberg Air Force Base, where it met with the Mitsubishi-built Sierra lower stage before the combined stack moved to the former Titan II launch pad at SLC-4W.

    Though Sierra appeared to be on-track for a debut by early 1996, Martin-Marietta’s executives had become nervous about the company’s near-total lack of revenue until that time. As Sierra development work concluded and the project moved into fabrication and testing, they sought ways to make their vast pool of intellectual capital turn a more immediate profit. The LSAV contract was the clearest way to do that. Banking on their reputation for success in vertical landings, and on the fact that the company had recently built a new spacecraft from scratch without running too far over their planned schedule and budget, Martin-Marietta submitted its bid in the hope of securing a revenue stream that could pad the company out if Trans-Pacific Launch Industries turned out to be a bust. To the delight of its shareholders, it succeeded. The infusion of NASA capital into Martin-Marietta’s coffers helped insulate the company against the potential consequences of a Sierra delay.

    While the American contractors popped champagne corks in celebration of winning the prestigious new vehicles, their European counterparts were hard at work rating the Hermes capsules for lunar operations. In close cooperation with their counterparts at McDonnell-Douglas and the Johnson Space Center, Airbus engineers conducted fit tests and developed the hardware necessary to transfer power and cooling fluid between the crewed capsule and the LTV it would ride to lunar orbit. Though the spacecraft milestones were steadily checked-off, the first LTV-adapted Hermes was not ready to join the first LTVs on their 1996 orbital demo flight, due to a distressing incident when an oxygen resupply hose (meant to tap off some of the LTV’s residual oxidizer as a supplement to the capsule’s breathable air) exploded during testing due to a mistaken conversion between kilopascals and pounds-per-square-inch, forcing a systematic reevaluation of the eCRV’s compatibility with American-built hardware (for its part, McDonnell-Douglas responded by publishing SI guides and manuals for its hardware).

    As the Clinton administration made its decisions on how to exert their influence on US and global space policy, the existing LTV program continued pushing onward. The first completed LTV boilerplate was shipped from McDonnell’s plants for testing in the Plum Brook Station vacuum chamber at the Glenn Research Center in Ohio in August of 1994 for testing of the spacecraft’s actuators and tank performance vacuum. A key point was the ability of the system to reflect heat and prevent it from reaching the cryogenic propellants inside, reducing boil off and enhancing system life. It was anticipated that the same thermal insulation designed to resist the fires of entry could serve to reduce boil off, and indeed the incredibly low boiloff rates realized demonstrated the additional wisdom wisdom of the decision to go with soft cryogens for the LTV, one originally forced by density and assembly complexity concerns. However, it proved to be vacuum actuators which would dog the program.

    The LTV featured a complex arrangement of telescoping docking ports, a retracting nose heatshield cover, and an extendable and retractable solar array, which needed to survive extended periods in space during both the extreme heat of braking passes and the extreme cold of orbital night. The failure of even one actuator system and its backups to perform could lock the vehicle in a condition which made it unable to return to LEO, unable to power itself, or unable to dock for boost, fueling, and recovery. The actuating solar array proved the most difficult, with a tendency for the initial design to become jammed after extended cycling of heat and cold in vacuum conditions which had not manifested in early component testing. Re-evaluation of the test actuators on the boilerplate revealed a change in the bearings used in the actuator made after the initial proof tests, intended to reduce weight and increase design life, was actually impairing the function of the system. A switch back to the original design was quickly implemented, and testing at Plum Brook continued even as the second boilerplate awaited the arrival of its engine set from Pratt for test firings at NASA Stennis.

    The Lunar Transfer Main Engine had also had its share of teething problems. The small size of the engine meant that runaway combustion instability had very little space to work, and the engine proved reliable and consistent...once lit. The challenges of the LTME's expander-cycle dependence on engine heat for pump power and the ignition in space of a mixture which was relatively new compared to the proven kerosene/LOX or hydrogen/LOX of the F-1 and J-2 engines made those initial seconds the most challenging in the engine's operation. Increasing propellant flow too slowly starved the engine of coolant, while increasing too quickly lead to several LTME prototype chambers suffering hard starts similar to those of the J-2S-2 on STS-116. The proper balancing of flow, pressure, and pump speeds in these critical moments took repeated testing of the spool-up from head-pressure idle to ignition to full-thrust that required months by themself. The testing had to be done, however, to qualify the ignition transients in temperature and pressure to ensure the LTME would light reliably and consistently, the first time or the hundredth. This long life was also a complicating factor: though the expander cycle was relatively low-stress compared to higher temperature cycles, the LTME needed a lifespan measured in dozens of missions. Once margins were included, that lead to a requirement for testing for more than 100 starts per test engine, with burn times exceeding 25,000 seconds of life per engine. This lead to additional focus on the engine's pumps, turbines, bearings, valves, and seals. Even once the ignition transient was conquered in mid-1994, testing continued on a near-weekly basis at NASA Stennis on LTME test engines to build the required lifespan data.

    By late 1994, the LTME was judged mature enough to proceed to integrated testing, and the first full test set of four engines was qualified at Stennis, then shipped by air to McDonnell's assembly site to be assembled to the waiting set of boilerplate LTV tanks. For the first time, a complete LTV propulsion system was assembled, and the resulting Main Propulsion Test Article was shipped back to Stennis for testing of the engines together. Firings of the MPTA proved the effects of igniting all four engines together, the vibration modes of the integrated engines and tanks, and the effects of lighting only two engines at low throttle on the bells and chambers of the surrounding engines. With the completion of the MPTA tests and the final long-life engine tests, the LTV and the LTME had been proved in vacuum and as an integrated stage. The final proof was to see if the LTV could fly as a spacecraft on orbit. This task would fall to the next sets of tanks and engines off the line, integrated and designated as LTV-1 and LTV-2.

    The LTV-1 and LTV-2 vehicles were entrusted with one of the most ambitious and complex missions ever attempted in NASA history, one as pioneering and controlled as any outer planets probe and as intensively and rigorously scheduled and monitored as a manned Space Shuttle flight. Comparisons to the engineering-packed but little-remembered Apollo 9 mission were common, but if anything the LTV demonstration was more complex. The official mission calendar assembled by McDonnell and NASA engineers from Marshall and Johnson included no fewer than half a dozen mission-critical technologies which would see their first demonstration on the flight, a dozen docking maneuvers, the first firings of the LTME in space, the first full demonstrations of cryogenic propellant transfer in microgravity, and the first demonstrations of autonomous multipass aerobraking for large spacecraft in seven deceleration series totaling more than one hundred individual atmospheric passes. During one planning session for the mission, a group of NASA engineers who had used the occasion of a weekend in the Los Angeles area to drive to Las Vegas between weeks of meetings groused that if they could pull the mission off, it'd be a trick better than that they'd seen pulled off by the magicians Siegfried and Roy. For the rest of the day, the names were tossed around to differentiate between the flight plans for LTV-1 and LTV-2 in the complex schedule, and the callsigns stuck.

    The plan’s ambition was the result of the decision to test as much as possible with as few missions as possible, launching two LTVs fully fueled on the same Space Lifter. Once launched, the plan was to simply run down the demonstration checklist one at a time until issues were encountered or the mission was complete. Because of the tremendous capacity of the LTV, their delta-v unladen was impressive enough to allow the two vehicles, alone, to test every major element which would need proving out, assuming they held together. Alternate plans were considered in which short-fueled single LTVs would be flown inside the Space Shuttle, flown for incremental tests, then brought back down by Shuttle, but concerns arose over the cost and schedule of depending on multiple manned missions for the tests, and on flying crew to orbit with tons of sealed and volatile propellants on board, with no allowances made for venting in the case of a launch abort. Flying two vehicles on Lifter was ambitious, but it was also faster, better, and cheaper for testing than alternatives--magic words in the world of Administrator Goldin, who gave the plan his personal go-ahead.

    LTV-1 and -2 were tested in the height of summer at NASA Stennis, then shipped for final integration with radar and communications dishes and their launch adapter truss at Kennedy Space Center. Though plans were underway for a student competition to name the tugs, those names would not be officially assigned until their triumphant recovery at the end of the mission. For the moment, the nicknames created by frustrated engineers in a Seal Beach conference room had stuck, and the names "Siegfried" and "Roy" for LTV-1 and -2 respectively were in common use by engineers and mission planners. Thanks to a herculean effort by Public Affairs, the names had so far avoided use in any official documentation. Still, as the pair prepared for launch aboard the Space Lifter Constitution, many in the office responsible for sorting through competition entries to determine and official name figured it was probably only a matter of time before the unofficial ones slipped into press coverage.

    For all the worries about callsigns, aerobraking, the debut of the LTME, and the lifespan of the LTV in space, the biggest moment of terror in the Lunar Transfer Vehicle demonstration mission came during ascent aboard STS-240, launched on October 31, 1995. At just over a minute into ascent, while Siegfried and Roy were still inert inside their launch adapter and fairing, Constitution’s #3 engine telemetry began surging alarmingly. With pressure oscillating wildly inside the chamber, the automatic software shut the engine down, and began to throttle up the other four engines to compensate. As commander James Weatherbee and pilot Eileen Collins worked through checklists to complete the shutdown and confirm the throttle-up, Houston controllers worked through the implications and assessed the other engines. To all inspection, the data from the other four engines looked healthy, and none wanted a repeat of the Magellan accident with a critical payload arcing into the sea. However, there was still almost a minute left before staging and pushing on with multiple engines out could mean something worse: the loss of the booster, and possibly the crew, should there be any issues with the deployment of their cockpit entry pod.

    These were unprecedented but not unanticipated decisions. With the loss of an entire F-1B engine, the STS-240 controllers immediately went from a routine mission into deciding which of innumerable contingencies, exhaustively modeled flight profiles, and extensively simulated procedures applied. At more than a minute into the flight, the Space Lifter had sufficient reserve thrust that it could still make the nominal flight profile even with one engine out by running the others longer before main engine cutoff--the so-called "press to MECO" option. The next-best option was an "abort to orbit," pushing to separation on the remaining engines, aiming to leave the payload in some orbit, if not the intended one. If that couldn't be managed, it might be all the crew could do to jettison of the unfired upper stage and payload and return to Kennedy. The last, worst case option would be if the engine's failure had damaged the stage's structure, and might mandate the first ever manned use of the Lifter's ejection pod to pull the crew to safety as the booster failed. The booster controllers scrambled to review their data and pre-analyzed procedures to determine which contingency applied. The decision was rendered more fraught by the speed with which engine #3 failed: the Lifter had gone from five healthy engines to four in less than five seconds. Could the remaining massive engines be trusted? Quick but intense debate followed between the Flight Dynamics Officer and the three Booster operators. As the Flight Director weighed the decision, Weatherbee and Collins called down their own encouragement. "Houston, CDR. Number three out, but pilot say all others are solid. Are we go through MECO?" From the back of the line of consoles, the Flight Director could see as the Flight Dynamics Officer nodded to herself emphatically and the booster controllers exchanged a look. He made the call. "CapCom, tell them go to press to MECO. Flight Dynamics, get working updated retro procedures."

    The decision crackled up to Weatherbee's headset, and the crew set up the most optimistic of contingencies they'd hoped to never need. With the decision made to trust the remaining four F-1Bs, engineers hunched over consoles, as if by being closer to the screens they could get the telemetry slightly faster or wring just a bit more meaning from the data on their screens. Even the usual marker of main engine shutdown and a successful ignition of the S-IVD didn't bring relief. It was only after the required three F-1 engines relit and held through the retro burn that tension truly began to abate. The burnout of the S-IVD at an orbit several kilometers outside Lifter's usual delivery accuracy was only noted for later work. As their tasks on the main ascent finished, controllers paused, waiting for the updates as Constitution descended back to Florida. The appearance of the giant winged Lifter on the tracking cameras brought scattered whispers, then the touchdown of all three landing gear brought cheers to a degree rare among controllers in a program with more than 200 nominal landings under their belts. As Constitution rolled out along the Spacecraft Landing Facility's runway, scoring damage to the #3 engine fairing could be clearly seen, and investigators converged as soon as she came to a rest and the crew were extracted.
     
    Chapter 18: Chasing
  • “If you can walk away from a landing, it's a good landing. If you use the airplane the next day, it's an outstanding landing.”​

    Chapter 18: Chasing

    Like a newborn whale swimming after its mother, the T-38 chase planes rose to meet Constitution as she descended toward Cape Canaveral. By now, the Lifter was cruising almost placidly, subsonically down the coast, well within the Talons’ ability to match its speed. The two Talons met it, trailing it, one to port, one to starboard, each with a clear view of the Lifter from the edges of its engine bells to its bulbous, hollow nose. Cameras in each airplane span through their film, capturing the Lifter’s descent over the scrub and ocean for posterity, and for inspection by engineers on the ground. The Lifter had made this descent several times before, but now she’d carried a new payload up, with new possibilities for failure, be they falling chunks of ice or simply different scorching patterns due to the unpredictable airflow around the Shuttle’s complex lifting surfaces--so they inspected her again, just in case.

    The untrained eye would have lumped the two kinds of flying machine into the same class. Both bore delta-wings, allowing them to maneuver well above the speed of sound, and large rudders to manipulate the tenuous air high above Earth’s surface. The Talons, with their jet nozzles at their aft end, looked almost like juvenile Lifters, newly hatched, eventually to grow into mature space-planes. Even their paint schemes were not too dissimilar, each painted in the same glossy white, a NASA logo emblazoned on their flanks and tails. The black paint around the Talons’ cockpits, which protected their pilots from reflected glare, even matched the same marks painted into the coatings of the Lifter’s cockpit capsule for the same purpose.

    But these similarities were barely more than skin-deep. The Talons were high-performance jet airplanes, essentially an engine with control surfaces attached, designed for the maximum possible aerodynamic performance. They could remain in the air far longer than the immense Lifter, which was nearly done with its jet propellant after a mere half-hour of flight, but they could never match its speed or altitude, or the terrific heat and pressure of atmospheric entry. The Lifter, by contrast, was by now, aerodynamically, a brick--her immense volume was mostly empty, and as she plunged into the thick troposphere she seemed scarcely more maneuverable than a submarine. Her 10 jet engines were enough to let her fly, but not to fly well. Her power lay instead in the five now-silent F-1Bs at her aft end, stained with soot and scorched from the monstrous heat they’d generated, which had sent her beyond the realm of aerodynamics altogether.

    The Talons continued to tail their target, which had gone faster than they ever could and returned from a place forever beyond their reach. They could support her in these last moments of her mission, but, cosmetic similarities aside, they were fundamentally different creatures.


    Until the moment that Constitution's landing gear touched the runway of the Spacecraft Landing Facility, the situation had struck observers as frighteningly similar to the loss of Magellan: a critical exploration payload at risk as a Lifter stack struggled to power past a major propulsion anomaly. News networks had stayed with the launch coverage longer than they usually did, and continued to check in as Constitution made her way back to Florida. However, with the booster safely landed and the payload inserted into a stable (if slightly off-target) orbit, the excitement faded quickly. NBC, CNN, and other networks carried the post-launch press conference live,, but the followup press conference the next day covering the beginnings of the investigation received less than a five minute story. With the payload on orbit, the crew safe, and the hardware already being torn down, there was less of a story. NASA and STC announced quickly that the issue had been a major failure of the turbopump of the #3 engine, but the details of the causes rapidly exceeded the interests of many news organizations short of Aviation Week. The question was what had caused the failure, how to resolve it, and how long it would take.

    With direct access to the failed hardware, NASA, STC, and Rocketdyne were able to trace the root causes of the problem much faster than they could the Magellan failure. Instead of having to pore over the telemetry of a malfunctioning J-2S-2 and compare to engines in the same production batch, Rocketdyne and NASA were tearing down the very same engine which had failed while STC and NASA catalogued the effects in the surrounding engine compartment. The task was simple: catalog the smoke and char and the torn and twisted metal. The investigators could, in some cases quite literally, follow their noses to the problems’ sources. While industry engineers converged on the wounded booster at Cape Canaveral to evaluate damage and plan repairs, NASA investigators spread from Florida to production sites across the country to investigate the causes. The problems they’d find would determine how long it would take for Lifter to return to flight this time. Eager to divert attention to successes and with public interest in the near-incident falling off, NASA instead turned the focus of their public outreach to the new spacecraft Constitution had managed to launch.

    The excitement of Constitution's engine-out ascent was remote 295 km above the Earth's surface, as the S-IVD fired separation pyros and Siegfried and Roy detached from the cradles of their launch adapter. Though lower than intended, the altitude of their resulting orbit was sufficient for weeks of orbital life, and the LTVs were--if they worked--nimble orbital maneuvering vehicles. As NASA engineers set to work investigating the causes of the ascent anomaly, another team began the process of opening the tug's heat shields, deploying their solar arrays, and checking communications, power, navigation, and radar systems. For two days, the two ships coasted in formation, briefly testing their thrusters and using each other as calibration targets for their rendezvous and docking radar. Finally, in their first major burn, both stages fired to adjust their orbital altitude to the originally-planned 400 km base orbit, then set to work on a series of docking tests. Under autonomous control, Siegfried and Roy took turns as the active and passive spacecraft, testing docking at both forward and aft ports under varying lighting and equipment conditions. One early approach, testing the procedures for a single-radar-out maneuver, failed when the active tug, Siegfried, began to register non-existent relative motion to Roy, and aborted automatically. The issue, caused by an erroneous routine attempting to parse data from the disabled radar to check the active one, was corrected by a software uplink and the remaining 10 docking attempts were all successful.

    With the tug's orbital navigation and basic functions verified, it was time to confirm the function of the Lunar Transfer Main Engine in space for the first time. Roy loitered in the initial parking orbit, holding station, monitoring the measurable but tiny boil-off of methane and oxygen. While it marked time, LTV-2 repeatedly deployed and retracted its heat shield and solar charging systems to verify that the actuator issues encountered at Plum Brook were well and truly resolved. For its part, Siegfried lit its LTME cluster for its first extended burn of all engines, first with a small burn of a few hundred meters per second to check function, then, after a two-orbit pause to allow ground confirmation of the vehicle's onboard navigation, a larger burn which raised its perigee nearly to the Van Allen Belts. After a cross-check from the ground, Siegfried made one final burn, raising its apogee solidly into the lower Van Allen Belt. Siegfried lingered in the high energy flux for ten days, testing how the belt’s charged particles influenced its systems, and confirming that the radiation hardening installed would be sufficient for the nominal 5-day duration of a 30-pass aerobrake from lunar return trajectories. The boiloff from Roy was compared to Siegfried's tank pressures to determine how different heating and cooling cycles impacted the performance of the real LTV tanks on-orbit for comparison to ground data from Plum Brook.

    Once this loitering period was complete, it was time for Siegfried to return to LEO. However, unlike its previous adjustments, this wouldn't be an entirely propulsive maneuver. The use of aerobraking for the LTV was critical to getting sufficient performance from a stage which could return in the Shuttle payload bay. However, to date the entire body of knowledge on aerobraking which did not result in immediate descent to a planet was the 1991 orbital adjustments of the MUSES-A spacecraft Hiten from Japan's Institute of Space and Astronomical Studies. In two passes in that year, the spacecraft had adjusted its lunar flyby orbits by skimming the upper reaches of Earth's atmosphere, shedding more than a kilometer per second of velocity to tailor its apogee height. This braking on a more-than-translunar trajectory was a remarkable achievement for a spacecraft protected not by insulation blankets, metallic heat shields, or ceramic tiles, but instead by foil sheeting and exposed solar array segments. However, while Hiten was a remarkable demonstration, and an achievement NASA and McDonnell had eagerly observed and offered some assistance analyzing, MUSES-A was barely two hundred kilograms, where the LTV would be fifteen times larger and would have to not simply skim the atmosphere, but dive deep into it in order to make its return to low Earth orbit. On its return to Earth from its initial Van Allen belt passes, Siegfried demonstrated its ability to carry out this braking by performing the last 250 m/s of braking purely aerodynamically.

    As LTV-1 dove into the atmosphere, the mood in Houston's Mission Control Room was tense. This early in the demonstration mission, Siegfried was still ballasted with enough propellant to be more than three times heavier than it would be on return from a nominal flight. While the braking pass was relatively small compared to Hiten's attempts or passes planned later in the mission, the extra ballast would raise the stresses on the vehicle significantly, providing a test to prove the safety margins at nominal levels. In order to protect it from the heat of entry, LTV-1's main communications antenna was retracted within the aerodynamic flare. Telemetry would have to come from status tones passed at low bandwidth over smaller omni antennas and on what data could be collected from the ground. In order to maximize the data return, the pass was timed to take place in the early morning over the Eastern United States. A NASA P-3 Orion served as an airborne camera platform to record the pass visually, while military radars would track the spacecraft's position and velocity during the five minutes of peak heating. Siegfried carefully adjusted its perigee to skim the atmosphere at 95 kilometers--barely within the Von Karman line--then bored in on its entry trajectory. The pass was tense for engineers who had worked months and years to prepare for the mission, with more in common with a probe landing than a normal launch or a manned mission. There was nothing to do but watch the minimal telemetry which could come back on the secondary antenna, a simple condensed "attitude" and "temperature" return played alongside video from the Orion and radar tracking on the main screens. The minutes ticked past with agonizing slowness as Siegfried swept down the nominal trajectory.

    Then, almost without noting, the perigee was past and Siegfried was rising once more. It was headed out of the atmosphere, but the question was how far above the atmosphere it would be after the adjustment. Finally, LTV-1 passed back over the Von Karman line and tracking radar confirmed than its apogee had been adjusted to within fifteen kilometers of the nominal planned distance. A pre-scheduled burn at apogee stabilized the perigee back above the atmosphere, then data began to be down-linked from the on-board recorders. Thermal data had been reported by dozens of thermocouples embedded in the backside of the heat-shield, sidewall insulation, and flare, as well as pressures and temperatures in the internal passages for circulating boiling methane as an active cooling system, and at carefully selected points on the outer skin of the LTV. Siegfried's armor had protected it, and LTV-1 was healthy. Another pass two orbits later confirmed it, then two more completed the return to the orbit where Roy had waited.

    However, one test was insufficient data to retire the risk from lunar entry velocities which would need to burn off ten times the velocity Siegfried had started with. Transferring much of its stored propellant to fill Siegfried's depleted tanks, Roy tested its own engines with fully propulsive maneuvers, then set to work on a series of tests of the aerobraking technique under more and more aggressive initial conditions. First, Roy would boost to a planned initial apogee, then over an appropriate number of passes brake down to LEO again, simulating the tail end of a multi-pass return from translunar booster or lunar return trajectories. The apogees rose from 1,200 kilometers on Siegfried's first test to 2,500 kilometers on Roy's first, then to an altitude above 7,250 kilometers which would require sweeping through the entire inner Van Allen Belt, and finally to an apogee just above geostationary orbit.

    What had been tense on the first trial quickly became routine, as each multi-pass return required a multitude of passes and the knowledge of purely atmospheric orbital adjustments expanded by multiple orders of magnitude. The LTV demonstration controllers settled into a routine as grueling as a manned mission, but with the duration of an unmanned probe: a series of passes starting a few times a day, then rising to every few hours forming an intensive period in the middle of every week, followed by a few days of propellant transfers while the data was digested and the go-ahead given for another set. For a mission which had started with concerns it might not reach orbit, the routine was appreciated. The worst headache came during the highest energy initial passes, when meteorological models estimated elevated upper atmospheric density. While relaying instructions to LTV-2 to raise the perigee to reach the right density altitude for braking, an invalid command sequence was uplinked by accident. Attempting to parse the commands in preparation for the burn lead Roy’s computers to interpret the result as a radiation failure of its computers resulting from the pass through the Van Allen belts. The spacecraft tripped into “safe mode.” LTV-2 automatically adjusted its orbit ensure its perigee even in the worst case wouldn't result in an overly aggressive path, then switched to low-level operations to await a resolution. With the brake opportunity missed, NASA engineers on the ground spent the time to perigee diagnosing the problem and reworking procedures for command uplink on time-critical maneuvers. With updated commands uploaded, Roy made the proper braking pass on the next orbit and every one after it until it returned to its rendezvous with LTV-1 in LEO.

    Other than the one headache, Roy held up under the trials as well as Siegfried had, and data from both continued to confirm expected boil-off rates. With almost ten weeks of evaluations under their belts, McDonnell and NASA engineers carefully assessed the health of both vehicles. The remaining propellant had been carefully husbanded for a fool-proof flight of both tugs. For the first time, both tugs departed LEO together as a stacked unit. Roy's engines were called upon one more time to push both tugs to an apogee near that of GPS satellites. As Roy cast off and adjusted its perigee for a four-day return to LEO, Siegfried lit its own LTME cluster, burning nearly all its remaining propellant to push itself onto a circumlunar trajectory. Not only would LTV-1 make the most aggressive test yet of the system's aerobraking, but it would also become the first LTV to fly--however briefly--past the body they were intended to reopen to human access.

    Engineers monitored the status of the vehicle on its outbound trajectory, as Roy settled with little notice into a long-term parking orbit to await pickup by Shuttle for inspection. Images from LTV-1's docking and navigation cameras captivated many audiences back on Earth as they captured the Earth shrinking behind it, then the growth of the moon from a disc to a ball and finally into a rugged, rubble-strewn surface spread out beneath. Siegfried shot past the limb of the moon, beyond the view of Earthbound observers and communications, past the point on a full flight where it would have fired its engines to enter lunar orbit, then flew once more into view. The spacecraft's communications reassured controllers: LTV-1 was on course and speed, headed for the first of the 60 passes which would distribute its braking energy. The originally planned 90-day LTV Demonstration mission drew comparisons to Apollo 9, playing a similar role to the mission which had come nearly thirty years before. It was, in some ways, even more ambitious: not just the LTV's first flight in space, but a full demonstration of nearly every capability of the entire system. Once LTV-1 and LTV-2 were returned to the ground, the final preparations could be made for the launch of the Lunar Transfer Vehicles still being finished: their near-twins, LTV-3 and LTV-4, already test-fired at Stennis and in final assembly at the Cape, and LTV-5 and 6 still under construction at McDonnell's plants. However, before they could return home aboard the Space Shuttle, the Space Lifter’s issues needed to be resolved. The stages waited, circling in a low Earth orbit, for their ride home.

    The major details of the Engine #3 failure on STS-240 emerged quickly, almost as soon as the first responders were able to examine the engine and spot the gaping holes in the turbopump assembly. The failure had been the result of a catastrophic failure of the pump’s turbine assembly, which NASA knew was one of the oldest in the F-1B fleet. As NASA, STC, and Rocketdyne tore down the remains of Engine #3, the initial leading explanation was fatigue cracking of the turbopump impeller blades--a major concern with the long-term life of rotating hardware. As a precaution, the turbopump’s turbine and impellers were routinely inspected after every flight with a borescope. However, as the F-1 family had a history of nearly two thousand in-flight firings without issues, engines with no other warning signs were typically only removed and fully torn down during the ongoing SLIP inspections, which had quietly transitioned from a “Spacecraft Lifespan Investigation Program” to a“Spacecraft Lifespan Improvement Program”. Engine #3 had been inspected and reinstalled at Constitution’s SLIP IV inspection in 1993, and was due for replacement at SLIP V in 1996. As a prime area of concern in a SLIP inspection which NASA engineers might have been overdue, the chunks of turbine blades were carefully extracted from the aft end of Constitution’s engine bay and catalogued and the impeller’s violent disassembly carefully reconstructed. By comparing the length of each blade remaining on the hub, the engineers could reconstruct the order of the blades’ failure, finding which had failed first and which had failed as shards of other blades was blown into them by the pressure gradient.

    As the engineers attempted to reconstruct the failure order, they made an interesting observation: the pattern showed multiple initial points of failure. Moreover, when sections of the blade were subjected to metallurgical testing and visual inspection, looking for signs of fatigue crack initiation near the failure point, none were found. The inspections turned towards the unusual pattern of damage to the blades, looking for other explanations. Fatigue of the impeller blades had apparently not been the root cause--instead, the blades had been broken by some other fault. Once this was understood, other evidence that had been accumulating was recontextualized, and the truth emerged: the damage to the seals between the fuel and oxygen impellers wasn’t a side effect of damage, but the cause. Unusual wear to the seals between the turbine shaft and the case had allowed a leak between the two impellers. Sensors registered the worsening mismatches in fuel and oxidizer flow, resulting in uneven gas generator power and main engine thrust. However, before the stage could take action, the mixture had ignited, damaging blades and rotor bearings, driving the shaft out of alignment and balance. This had caused otherwise healthy blades on the impeller to contact and clip the case wall. The result had been a catastrophic failure of the impellers and an explosion of shrapnel and shards as the engine’s sensors belatedly reacted to close off propellant flow.

    Locating the cause of the failure had ultimately taken a mere 11 days, as technicians and engineers had worked side-by-side around the clock. Resolving it would take several times longer. Every available flight engine was scheduled for teardown and inspection of their turbopump assembly, and other seals throughout the engine were re-evaluated. Intrepid, which was in for her own SLIP IV inspection, already had had her full suite of engines removed and made the main subjects of the inspection. One seal turned up similar damage. Though not serious enough to cause a major leak, the confirmation of the cause caused mixed feelings. The confirmation of the source of the issue came as a much-desired relief, but the issue was also a wake-up call that suggested that other issues might lurk within the Space Lifter’s RS-IC fleet. The F-1B design was nearly twenty years old, based on a design closing in on forty. Much as had been revealed six years prior on the S-IVC assembly process, familiarity had bred complacency. Major inspections were scheduled for every RS-IC booster in the fleet over the next months. RS-IC-604 Liberty was the first to be certified as clean. As the youngest Lifter, her SLIP schedule had her most recently out of SLIP’s hands and with her most recent inspections she already had a set of freshly torn-down and rebuilt engines installed.

    NASA investigators reviewed every available scrap of documentation regarding her inspections before finally certifying Liberty as fit to fly. When STS-240 had caused shades of Magellan’s failure to swim before NASA observers, there had been worries a similar year-long stand-down might result. Instead, Liberty and the STS-241 mission were rescheduled for March 4, 1996. The payload was a pair of Hughes communications satellites, paid for by a satellite television supplier aiming to build out their global market. The customer had willingly accepted the risk of the mission in exchange for being bumped to the head of STC’s launch queue and a highly secretive discount on launch price. The launch went off without a hitch, and inspection of the engines after the mission showed no issues. While this would delay the typical rapid RS-IC turnaround, the rest of the RS-IC fleet was finally being cleared of the turbopump issues. The Space Lifter began to ramp back up to operational status with the launch of the Space Shuttles Discovery and Destiny aboard STS-242 and 243 mere weeks apart, with STS-242 retrieving LTV-1 and STS-243 retrieving LTV-2 in twin missions. The return of the stages to Earth marked a dramatic end to a test mission which had seen, aboard its launch vehicle, a dramatic benefit of both the lifecycle risks associated with reuse and the safety benefits enabled by the return of hardware for inspection.

    With the success of the mission and the transition of LTV from a test phase to a man-ready transport system, the vehicles were all to be given names. Originally, the Public Affairs office had selected the names Lewis and Clark to be bestowed upon LTV-1 and LTV-2 upon their recovery by the STS-242 and STS-244 missions, named for the famous American explorers. Unfortunately, the high profile of the LTV Orbital Demonstration in the wake of their barely-successful launch worked against them. Despite official injunction, Siegfried and Roy remained in common usage among the LTV support staff, a fact which delighted the public, and the magicians themselves, when Popular Science revealed this fact in a human interest article in 1996 titled “Lions and Tigers and Rockets, Oh My!" The NASA PAO eventually gave up on trying to institute the new names, quietly retroactively authorizing the original call-signs and assigning the original planned names to LTV-5 and -6 instead. LTV-5 and -6, in turn, passed their planned names on to the planned LTV-7 and -8, to enter service in the early 2000s. Those, eventually, would take the names Amundsen and Scott. The first four LTVs to be named were gathered for their christening, with the space-flown LTV-1 and LTV-2 presented on dollies next to their pristine pre-flight counterparts, which were with due ceremony named Tenzing and Hillary after the mountaineers who summited Everest. Once launched in July, these would await only the launch of an eCRV and crew to bring astronauts to lunar orbit for the first time since Apollo 17 had departed. In the meantime, the two spacecraft conducted their own more routine break-in period, testing their capabilities by carrying the first TDRSS-L satellites to lunar space.

    The first flight of a Hermes capsule on the LTV would have to wait until 1997, when the Space Shuttle Destiny delivered an unmanned capsule to a docking with the LTV-3/4 stack, returned to LEO and refueled from their proving flights to deploy TDRS satellites to cislunar space. This mission, ILP-1, was doubly notable for the first demonstration of cryogenic propellant transfer from Trans-Pacific Launch Industries’ Sierra rocket, which transferred a small quantity of methane and oxygen from a tank in its payload bay into LTV-3 and back, cycling it back and forth several times to demonstrate TPLI’s ability to service the Lunar Transfer Vehicles, and to help prepare for TPLI’s coming propellant resupply missions. Coming on the heels of TPLI’s maiden launch of a full Sierra rocket from their initial test site at Vandenberg, these early propellant transfer missions were a critical part of TPLI’s process of proving out their new Sierra launch vehicle as they prepared for its entry into the commercial launch market. Indeed, the same mission which carried the test propellant transfer hardware for the ILP also carried another test payload: the first orbital demonstration of the new smallsat bus intended for use with Geostar’s Arachne LEO communications constellation. With confirmation of the bus’ functionality, Sierra began to work up their flight rate launching batch after batch of Geostar’s new constellation from Vandenberg while they completed final commissioning of their launch site at LC-40 in Florida.

    TPLI’s successes in ramping up the Sierra flight rate over 1996 and 1997 would have been worrying enough for Boeing and the Space Transportation Corporation if their ambitions had been limited to low Earth orbits. However, Martin and Mitsubishi also had their eye on the same geostationary market which had, for years, been the nearly exclusive domain of the Space Lifter. For decades, the only payloads for which the Space Lifter had not been the first choice were those too small to economically use it or those customers with institutional concerns which prevented the use of an American launcher. The Russian Groza system had been some competition when it became to be available on the commercial market, but the cost savings over Lifter had been matched by concerns about Russian quality and export/import restrictions. In the wake of Groza’s muddled international debut, STC's expectation of a near-monopoly had only intensified in the early 1990s, culminating in their attempt to sabotage the memorandum of understanding between NASA and TPLI to eventually even consider certifying Sierra for ILP propellant.

    Now, Sierra could not only match Lifter on cost for the mid-sized payloads which were STC’s bread and butter but reach even lower cost levels Lifter couldn’t hope to match. Worse, the Sierra debut mission had flown directly between the STS-240 failure and the Lifter’s return to flight--an issue caused by an aging rocket cast against the newest wave of reusable launchers. Though press releases were carefully polite, a small wave of geostationary service providers announced contracts with TPLI for “schedule assurance” backup slots aboard Sierra for payloads with scheduled Lifter missions in coming years. These might also draw on a new capability for Sierra-launched payloads to access this lucrative, higher-energy orbit: though initial GTO launches by Sierra were served with an Aerojet expendable solid third stage, news emerged in late 1996 of negotiations between TPLI, NASA, and McDonnell-Douglas to use portions of the LTV fleet in a single-stage commercial role delivering satellites to GTO or all the way to geostationary orbit between ILP missions. Now, Boeing was disquieted to not only face growing domestic competition but also to see their STC partner McDonnell-Douglas rapidly moving to take advantage of the situation. Though Lifter improvement, augmentation, or replacement plans had percolated within Boeing and Marshall Space Flight Center for years, the rapid emergence of Sierra as a real competitor meant that 1997 saw these plans rapidly gain support at the highest levels of Boeing’s space division.

    While the competition between two of the launch vehicles which enabled it heated up, the unmanned Hermes flight to Low Lunar Orbit was a marvel of international co-operation: a European capsule launched by an American Space Lifter, with demonstration fueling from a joint American/Japanese launcher, and support from other nations around the globe. The mission carried a handful of scientific instruments and experiments (mostly radiation sensors to validate the capsule’s polyethylene shielding and a handful of student experiments focusing on either life sciences or lunar observation) in addition to its crash-test dummy passengers, and during its month-long quiescent stay in a near-polar lunar orbit, it demonstrated the use of high-efficiency electric thrusters like those intended for the Low Lunar Orbit Platform for station-keeping in the Moon’s extremely lumpy gravitational field (which, while mapped in greater detail by the Lucky 7 mission, remained a hazard to long-term missions near the Moon). However, its chief focus was the shakedown of the improved heat shield. Not since 1972 had human passengers reentered the Earth’s atmosphere at such a fantastic rate, and as much as computer models and hypersonic wind tunnel tests indicated that Hermes could withstand the challenge, no engineer or manager on the ground was willing to approve a crewed mission without a successful unmanned shakedown. The heady “waste anything but time” days of Apollo had given way to a more safety-conscious attitude, criticized by some as “overcautious,” “wasteful,” and even “effeminate.” These voices were few and far between, however--even the most enthusiastic advocates for the immediate conquest of space generally recognized that celebrations of heroic martyrdom would not sway congressional investigators if the worst did happen.

    As it turned out, the unmanned Hermes capsule completed its month in Low Lunar Orbit without incident, and the LTV to which it was docked, LTV-4 “Hillary”, relit its engines successfully after a month of slowly orbiting the Moon. This marked the longest time yet between LTV engine burns, and testified to the efficacy of the spacecraft’s power and thermal control systems, as the month of rapidly-shifting temperature extremes had not seemed to impact its propellant supply. Several hours before Hillary came in for his (in a break from tradition, the LTVs had been addressed by male pronouns, a practice begun when First Lady Hillary Clinton toured Kennedy Space Center while LTV-4 was in the midst of pre-launch processing) first aerobraking pass, the capsule retracted its umbilical connection and oriented itself for a much hotter, deeper entry to Earth’s atmosphere. Drawing on Russian experience with the Zond program, Hermes used a “skip” reentry technique, to allow the capsule to maneuver in Earth’s atmosphere to its landing site at Edwards Air Force Base in California. This was the first of many technological innovations the ILP would demonstrate over the Apollo program, and eliminated the need for a large, costly fleet of naval vessels for regular recovery.

    No sooner had the unmanned capsule been recovered in the Californian desert than NASA announced a launch date for the next mission in the ILP, ILP-2. Unlike ILP-1, ILP-2 would not fly a Hermes capsule at all, but deploy the Low Lunar Orbital Platform to the same polar orbit that the first Hermes had occupied. The LTVs assigned to ILP-2 would return without any payload. ILP-2 would also be propelled by LTV-3/4, after those vehicles were refueled by a series of Space Lifter and Groza flights. The final Lifter propellant flight also carried the LLOP, which, separating from the propellant tug, briefly maneuvered to its own docking with LTV-4. This operation was one of the more complex actions the LLOP would have to take during its lifetime--it was designed to primarily operate as a passive target for docking spacecraft, or to use its small robotic arm for payload transfer with docked lunar landers. While capable of maneuvering to a docking on its own, in the event of a lander failure at close range, its control systems were not optimized for that. Still, after one false start, the LLOP successfully docked with the fully-fueled LTV stack.

    Departing Low Earth Orbit on September 9, 1997, ILP-2 entered Low Lunar Orbit four days later, and the LLOP separated from Hillary on-schedule. Extending its small set of solar arrays and radiators, the LLOP took its position at the same polar orbit that the ILP-1 Hermes had occupied months earlier. Like the earlier capsule, the LLOP was equipped with a set of electric thrusters for station-keeping. Though NASA public relations material played up the significance of this equipment, as it was the first use of electric propulsion on a manned spacecraft, its use was almost evolutionary, not revolutionary. Similarly-sized systems had been developed for stationkeeping at geostationary orbit for the larger busses a Space Lifter could dual-launch. Indeed, the LLOP’s system was the standard set of four thrusters with which Hughes had been equipping its geostationary satellites for years--which should come as no surprise, given that the LLOP was, ultimately, a Hughes commsat bus mated to a Grumman MPEM and equipped with a spare Spacelab robotic arm.

    Though primarily intended for logistical support of manned and unmanned lunar surface operations, the LLOP did have one instrument for Earth observation. At the suggestion of Vice President Gore, inspired by the influential “Blue Marble” photograph taken by the crew of Apollo 17, LLOP was fitted with a telescopic camera that could photograph points of interest on the Moon’s surface, and also capture whole-planet views of the Earth. It was Gore’s hope that a steady stream of earthrise pictures, regularly uploaded to the NASA website for public consumption, might spur greater interest in environmental sciences. Though engineers at JSC and Hughes had griped about the late change to the spacecraft’s design requirements, the LLOP had enough power, communications bandwidth, and thermal control capacity to handle a camera and some smaller instruments. Like Spacelab before it, LLOP would serve as an anchor for opportune science experiments, even those with no connection to its original purpose.

    All things considered, the Russian space program weathered the fall of the Berlin Wall far better than might be expected. Though budget cuts had been a fact of life after 1985, the military and civilian (though, in truth, the distinction is blurry) branches of the new Russian Federation’s program survived the period of 1989 to 1991 without catastrophic losses. The satellite constellations the Russian military had planned to support their overseas power projection were not growing, but Russia was in no condition to operate in Africa anymore anyway. The domestic satellites continued to provide communications and meteorological service even to the Russian arctic. No cosmonaut had been killed in space. Most importantly, Ukraine continued to supply Groza stages to its former master.

    The situation began to change in 1994. The start of the Chechnyan War brought a sudden chill in Russo-Ukrainian relations, already tense due to disputes over Crimea and Sevastopol, and had suddenly thrown the availability of Groza stages into question. The Russian Federation was willing to invest money into securing the independence of its space assets from its western neighbor. The most immediate goal was the replacement of the Groza core stage with an indigenous Russian design. Energia rose quickly to the challenge, proposing a new, fully-reusable core stage powered by their state-of-the-art RD-701 rocket engine, an engine unique in that it could burn either hydrogen or a mix of kerosene and hydrogen. The proposed stage would be cross-fed from modified (stretched) Raskat boosters, off-loading a great deal of the core stage’s structural mass onto the boosters, which, staging at a lower velocity, had less impact on overall payload. The system was elegant, leveraged the best innovations in Russian aerospace engineering, and was far beyond the means available to the Russian Federation in 1994.

    When Roskosmos told Energia as much in later 1994, the company took a while to get the memo. Yuri Semyonov, the company’s President, submitted designs for a Mir-2 that would be launched by the proposed rocket, and for 18-tonne communications satellites that it could deploy with a full complement of four Super Raskat boosters. Eventually, the Russian government’s patience wore out, and, with heavy government pressure, he was forced out. He was replaced with Oleg Sribielnikov, a former manager at NPO Salyut, which had manufactured the Proton rocket before that program’s cancellation.

    Sribielnikov proved far more reasonable, and revised the core stage proposal into a staggered development scheme influenced by the American Space Transportation System, which did, sooner or later, reach its original goals. As Phase I, Energia would replace the Groza core stage with an RD-701-fired expendable rocket stage of the same diameter, which could be serviced with essentially the existing Groza support infrastructure in Russia and Kazakhstan. Phase II would involve the Russification of the Raskat system, building modified stages in Russia and modifying the Ukrainian-built stages to the new specifications. Phase III, ultimately, would replace the disposable core with a reusable one, along the lines of the original Energia proposal. The new vehicles would bear the names “Baikal,” for the booster, “Kama,” for the expendable core, and “Volga” for the reusable core. These good, Russian names would expunge the influence of the Banderites from the most visible symbol of Russia’s continued potency.

    Unfortunately, it took longer to get the vehicles to the launch pad than the Russians initially hoped. While the RD-701 was essentially off-the-shelf in 1994 (having reached the test stand shortly after the dissolution of the USSR), corruption, budget-cuts, and poor quality-control, together with a brain drain of former Soviet engineers to the West and, to a lesser extent, saber-rattling minor powers, conspired to delay the first flight of the Kama booster until 1999. By then, however, a new administration had taken power in Russia. Led by charismatic authoritarian Vladimir Putin, and experiencing a new spike in revenue from gas sales to Europe and China, Russia endowed Energia with considerably more funding for the Baikal booster, which reached the launch pad in 2002.

    To this point, the Russian engineers had been, to some extent, simply duplicating the work of the Yuzhnoye Design Bureau. The final phase of the Energia development scheme, the development of the Volga core stage, involved developing a winged vehicle that would reenter from orbital speeds. This was new ground for the Russian engineers, and worse, it was ground more important to the civil and human spaceflight programs than to the military space program. The Russian military had, with the launch of the Baikal-Kama system, regained its independent space access--the Volga core stage was, while interesting commercially, not worthy of funding from the Russian military. Despite a heavy investment from Gasprom and attempts at a partnership with China and with India, Volga appears far from the launch pad, and her future is uncertain.

    The Mir space station was the most at-risk part of the former Soviet space program. As the most visible part of the Soviet space program, manned spaceflight was not going to disappear from Russia entirely, but flights to the station were cut back drastically. Plans to have the station permanently crewed were shelved in 1992, as the Russian manned space program became little more than a “show the flag” effort. The upgrade to the Uragan fleet's heat shields, replacing the original time-saving ablative coat with a tile-based system similar to the American Shuttles, seemed hopelessly optimistic in retrospect, as the long stand-downs between Uragan flights left more than enough time for complete TPS replacement.

    This situation persisted, with Russia just proud enough to continue funding annual Uragan flights to Mir but not rich enough to do more, until late 1993, when American entrepreneurs Jeffrey Manber and Walter Anderson re-entered the picture. Through contacts Manber had gained in Russia in 1988, the two pitched a novel revenue stream for the Russian space program: orbital tourism. Under their proposal, an American company (named “MirCorp”) would purchase a 45% interest in the space station, with Energia (the Russian design bureau reorganized into a semi-private corporation) holding the remaining 55%. MirCorp would finance the modification of one of Mir’s laboratory modules (of which two remained in Energia’s warehouses, not fully outfitted) into a habitat module for visiting tourists, as well as partially subsidizing flights of tourists on Uragan flights to the station, similar to the way commercial comsats were loaded onto Shuttle missions with excess payload by STC in exchange for booster cost reductions. The company would also sell laboratory space in Mir’s other laboratory modules to customers in the US and Europe (and, later, India and China), taking advantage of low Russian flight costs and a wide-open flight manifest to market to scientists anxious to get their data before retirement. The arrangement would, for the first time, enable Russia to actually fly Uragan at something approaching the frequency of its American counterpart.

    MirCorp found considerable support in the US State Department, which was eagerly looking for ways to slow Russia’s brain-drain. For a long time, the Soviet Union had cooperated with anti-American regimes, however questionable their actual Communist credentials, and with the demise of the Soviet economy, many of those regimes (like Iraq, Iran, and Libya) were inviting Russian rocket scientists to settle full-time and take positions as chiefs of their missile development programs. The US State Department was willing to assist any effort to keep Russian engineers in Russia, provided that it did not compromise America’s premier space power status. With NASA setting its sights beyond Low Earth Orbit and microgravity research, there was no obvious roadblock to cooperation between American and Russian companies in space. In partnership with the US Department of Commerce, the State Department established the Office of International Space Commerce, to regulate the import and export of orbital technology, in order to better regulate payloads as distinct from launch vehicles.

    The first MirCorp flight, designated KU-1 (Kommercheskiy Uragan, or “Commercial Uragan”), launched in 1996, carrying a crew of two Russian cosmonauts and two MirCorp engineers, along with space tourist Dennis Tito (an investment manager who had bought a seat as one of the first MirCorp tourist customers). Their task was to prepare the space station for the delivery of the new MirCorp module, dubbed Kommertsiya, or “Commerce.” Over the course of their 14-day mission, the crew members installed power and cooling system cables to connect the new module to Mir’s core power and thermal control systems, and tested communications with MirCorp’s corporate headquarters (and primary technical support center) in New York City. Tito, meanwhile, used Mir’s Spektr module to test an optical communications experiment sponsored by the Space Studies Institute and Geostar, in which Tito was a shareholder. The experiment, which demonstrated high-speed communication by means of a laser to a spacecraft, involved signals from a station on Earth reaching a reconfigured sensor on Spektr, and demonstrated data transmission rates of over 100 megabits per second.

    The second MirCorp flight, KU-2, launched in early 1997, carrying the Kommertsiya module, which was attached to Mir’s hitherto vacant starboard docking port. The crew, again two Russian cosmonauts and two MirCorp engineers, saw to the module’s installation and its startup, verifying that the microgravity exercise facilities, the new, American-designed “observation deck” (a very large window attached in place of an experiment bay), and the Visitor Airlock (a second airlock, complementing Mir’s core module airlock) were in working order.

    KU-2 brought Mir up to a “fully operational” status, in the words of Roskosmos, and provided the additional revenue stream necessary for the station to be permanently manned. Shortly after that mission departed, the Russian government launched a new crew of four cosmonauts to the station, the first of a new class that would permanently occupy Mir. Their Uragan carried in its payload bay the Mir Escape Capsule, a stretched derivative of the Almaz capsule that had begun development in the late 1980s to provide emergency escape from the space station, allowing crews to occupy it between Uragan flights. The capsule, with six seats, was spacious enough to accommodate the planned full-time Russian crew of four, together with up to two MirCorp occupants. Settling in for a nine-month tour on Mir, Russia’s newest class of cosmonauts picked up the torch dropped by their Soviet forerunners.
     
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    Chapter 19: Gear Down
  • “MAKSimized Performance, with the MAKSimized record. MAKSimize your Career with Boeing.”--Boeing/STC Promotional Pamphlet, handed out at university career fairs between 1997 and 1998.​

    Chapter 19: Gear-Down

    With her engines throttling back for landing, Constitution shed speed quickly in the last minutes of her flight. As she fell, her onboard systems made the final preparations for touchdown.

    The winged rocket may have been as large as a Boeing 747, but her aerodynamic qualities much more closely resembled the Concorde, or the XB-70 Valkyrie--like the other two supersonic planes, she cut through the atmosphere with a huge, swept delta wing. Unfortunately, while a delta wing worked superbly in the supersonic and hypersonic flight regimes, it could lift the Lifter only with difficulty as she bore down on the runway, crawling along at barely 200 miles per hour. Like all delta-winged planes, she had to point her nose to the sky, thirty degrees over the horizon, to achieve a high enough angle-of-attack for her wings to function.

    With
    Constitution’s nose in the air, her precariously perched pilots found their view of the runway blocked by the Lifter’s bulbous nose, leaving them landing virtually on instruments alone. This was no difficulty at all for trained naval aviators like Young and Crippen, who had cut their teeth on nighttime carrier landings, but that didn’t stop the engineers at Boeing from building into every Lifter a prosthetic eye, a tiny television camera mounted in a well under the nose along the spacecraft’s centerline, relaying a view of the runway up to a small CRT display on the dashboard between the two crewmen. As did the other instruments, that screen augmented the astronauts’ senses, giving them information that the classical five could not have discerned, integrating them ever so slightly deeper into the great machine whose brain they were.

    When the Lifter reached an altitude of 500 feet, Young threw a switch to deploy the landing gear. With another loud whine, hydraulic motors driven by power bled off from the Lifter’s eight jet engines pushed the gear well doors open and extended the almost comically-frail legs beneath the Lifter’s immense bulk. Compared to the gear on a heavy transport plane or an airliner, these landing gear were thin and weak. Had the Lifter attempted to stand on them when fully loaded with RP-1 and liquid oxygen, they would have snapped like toothpicks. Only now, when most of the Lifter’s volume was mere vapor and air, could they support her weight.

    Frail though they might have been, they had to bear the force of the Lifter’s impact with the Spacecraft Landing Facility runway soon, very soon. The pilots could not risk losing the spacecraft because they weren’t securely in place. Even as their dashboards lit up the indicators for “Gear Locked,” they called the Kennedy Space Center tower to confirm.

    “Tower, this is
    Constitution, can we get external confirmation that gear is down and locked?”

    “Roger,
    Constitution, your gear looks good from here. You are clear to land. Welcome back.”

    The consolidation of the American aerospace sector reflected the changing face of orbital transportation in the US. As Sierra reached first its ground tests and then its flight tests, and as McDonnell-Douglas and NASA put the Lunar Transfer Vehicle through its paces in flights first between LEO and other points in cislunar space, the last major players in American space launch--Boeing and STC, half of which Boeing owned--took stock of their options for the future. The early attempt by STC to lock TPLI out of the launch market for SEI propellant launches had, somewhat predictably, backfired, and NASA committed to developing a launcher-agnostic propellant transfer mechanism that would enable the agency to launch propellant for its Lunar Transfer Vehicles on any reasonably large launch vehicle. This was the first chink in Lifter’s armor, though many more would become apparent later in the 1990s. The Russian Raskat-Groza system did, by some margin, beat the American launch system on cost, and a handful of new commercial satellites signed on with the ex-Soviet launcher. On the horizon, Europe’s interest in air-breathing propulsion was also a potential competitor, but not one STC took seriously.

    TPLI was another story. Unlike Russia, Japan had the capital to invest in a new launch vehicle, and unlike the Europeans, TPLI’s backers had chosen a technically very conservative design--conventional chemical engines and two stages. Between that and Martin-Marietta’s ample experience with vertical landing, TPLI was well on its way to fielding an operational launcher in 1993, when the new satellite telephone company Iridium announced that it had contracted a dozen flights with TPLI to deploy its 72-satellite constellation to polar orbits. The company’s Sierra launch vehicle, while much smaller than the Space Lifter, was fully reusable, allowing TPLI to offer considerably lower per-kilogram costs to Low Earth Orbit than STC could offer on the Space Lifter without an outright government subsidy.

    The combined threats of foreign launchers and the half-foreign Sierra led STC and its parent companies to explore successors to the Space Lifters, which, after 15 years of service, were beginning to grow long in the tooth anyway. Increasing pressure to make a decision came from the spate of Sierra bookings of Lifter payloads following the 1996 STS-240 turbopump failure. Like their European rivals, the American consortium at first flailed about without a clear direction as to what exactly could replace Lifter. They explored options as varied as air-breathing SSTOs, second-production-run Lifters carrying atomic, winged upper stages, conventional chemical TSTO designs, and even more obscure concepts like laser propulsion.

    What finally precipitated a decision on the future of the Space Transportation Corporation, however, was a chance discovery outside Moscow by representatives of the Rocketdyne corporation, who were in Russia to evaluate claims about advanced staged-propulsion technology. Many of them had worked on HG-3, which had been planned to become the Space Shuttle Main Engine decades earlier, and so were America’s experts on staged combustion. While they did indeed find what they were looking for, in the form of N-1 heritage NK-33 engines, the more interesting discovery was a set of test-stand-qualified tripropellant rocket engines developed by the Glushko Design Bureau in the 1980s. These engines, designated RD-701 and RD-704 (two-chamber and single-chamber, respectively), could burn a mix of hydrogen and kerosene and used the highly efficient staged-combustion cycle that the Soviets had perfected for the RD-170. Rocketdyne’s managers struck while the iron was hot: as Energomash was looking for any source of income, they secured an exclusive contract to manufacture copies of the engines in the US, and brought the prototypes back to the US for qualification testing.

    Word of the remarkable new engines spread quickly upon their arrival in the US. It did not take long for Boeing’s engineers to conclude that they answered a great many of the company’s dilemmas, and to incorporate them into a plan for a successor to Lifter. Boeing’s new plan called for a Lifter-derived first stage, stretched somewhat and incorporating more advanced thermal protection systems to survive much higher-velocity reentry than the first Lifter could handle, powered by 12 RD-701 engines (license-built by Rocketdyne under the designation RS-40 to satisfy the USAF’s skepticism toward about whether Russia could or would supply enough engines). Carrying kerosene and liquid hydrogen, the proposed Lifter II could loft a considerably larger upper stage and stage at a much higher velocity than the original Lifter. Boeing also proposed a new upper stage, powered by a modified hydrogen-only RD-701, which would bridge the gap in size between the Space Shuttle Orbiter and the Lifter. Incorporating internal hydrogen and oxygen tankage, it would match the role of the “Fuji” orbital stage from TPLI’s Sierra and finally realizing the dream of a reusable, winged second stage. Crucially, both stages would mostly fly unmanned, eliminating the risk of a loss-of-crew on routine cargo delivery flights (though a crew pod was one of the possible payloads for the new second stage). The near-miss during the launch of the Lunar Transfer Vehicles on STS-240 and the brief debate about whether an abort-to-orbit or an immediate return-to-launch-site should be attempted underscored the importance of that particular innovation, as both Energia and TPLI made a point of saying that, if it came down to their launch vehicle or their payload, they’d sacrifice the LV every time.

    STC announced this Lifter II design (referred to in many early STC promotional materials as “MAKSimized Lifter,” in reference to the program for which RD-701 had originally been designed) in a major press event in early 1997, but the changes precipitated a reorganization of the relationship between Boeing, McDonnell-Douglas, Rocketdyne, and STC. The wave of consolidations in the 1990s and the new Space Exploration Initiative had given new strength and focuses to each of the firms. McDonnell had gained a new focus on on-orbit operations through the LTV, and was strengthening its investment in satellite manufacturing and operation. Boeing, in turn, had through its acquisition of most of Rockwell International become the leader of American manned spacecraft construction and operation, and it planned to tackle both stages of the Lifter II alone. Rocketdyne shareholders used the company’s rights to the RD-701 as a bargaining chip, and secured a large profit when the company was finally bought out by Boeing. With essentially the entire vehicle constructed in-house on new blueprints by Boeing, the new system had almost no Saturn or Apollo heritage. Instead of bearing the RS-IC or S-IVD designations, the new vehicles would simply be called Lifter II and Shuttle II (to be eventually condensed down to just Lifter and Shuttle when they supplanted the older vehicles).

    The partnership between McDonnell-Douglas and Boeing began, then, to break down. WIth McDonnell primarily operating the LTV (which would provide, eventually, the majority of flights for American payloads to geostationary orbit) and no longer having a stake in the flight from the ground to LEO, the company planned to contract with TPLI to provide propellant for the LTV and even to recover it for servicing. As this situation developed, Boeing proposed the radical step of dissolving their old partnership and simply buying out McDonnell’s share in STC, which would become a wholly-owned subsidiary of Boeing. With the Commerce Department’s blessing, the deal went through in 1997, and the Space Transportation Corporation became a Boeing trademark that year. McDonnell-Douglas, however, continued to provide S-IVD stages for Space Lifter operations until the final retirement of that system in 2002.

    The development of the MAKSimized Lifter proved a surprisingly straightforward program. With the engines essentially completed, the primary challenges were fabricating an entirely new airframe and testing the autonomous RTLS software. For a company as experienced as Boeing, these were straightforward challenges, and the Lifter II swiftly met its development milestones, reaching powered atmospheric flight tests by late 1998. Early in 1999, the first Lifter II arrived at Stennis Space Center for a static fire test. Emplaced on the same stands that had once tested the first Lifters and their Apollo-era progenitors, its twelve RD-701 engines roared to life together for the first time, finally demonstrating on American soil the full potential of the staged-combustion cycle.

    The Lifter IIs would spend much of 1999 and early 2000 in atmospheric tests alone, unfortunately. The reusable second stage proved a tougher issue, as it faced the far rougher challenge of reentering from orbital velocity. Weight overruns frequently threatened to doom the program, and Boeing’s engineers had to work relentlessly to shave off excess weight while, at the same time, not compromising the new vessel’s structural integrity. Subscale test articles, launched on sounding rockets and, once, as a Shuttle secondary payload, helped to validate the aerodynamic design and the performance of the lightweight (but somewhat fragile) metallic heatshield, which promised lower maintenance costs than those which had dogged the original Shuttle.

    The biggest hurdles that the Lifter replacement effort had to clear were not technical, but administrative. The Lifter was, for a long time, the only launch vehicle that could loft the US government’s heaviest payloads, military and civil. By the late 1990s, the system had demonstrated an unmatched flight record, with well over 200 successful orbital insertions and only one loss-of-payload event. The National Reconnaissance Office had come to depend on the Lifter, as no other American launcher could orbit KH-12 satellites or service them (as the Lifter could when it launched the Shuttle). NASA depended on it for crew access to space (though an effort to develop a Commercial Crew Services contract foundered after opposition from Texan congressmen). The contracts between STC and the US government, going back to that venture’s foundation, had insisted on the company keeping Lifter services available to the government even in the absence of commercial customers. While the Lifter dominated the commercial launch market, this was never a problem.

    By the late 1990s, the changing economic picture in space meant that Lifter’s flight rate would fall by 50%, mostly US government flights. The Lifters were also growing long in the tooth after between fifteen and twenty years of operation. Constitution’s engine loss was only the most dramatic example of a growing list of maladies reported at every SLIP inspection, from failing hydraulics to unreliable electronic to fatigued structural members. STC began to suggest that Lifters would have to be overhauled more often to maintain reliability, at greater expense. While the company could, technically, have operated Lifter and Lifter II in parallel, it would have had to rely on a fairly large US government subsidy to do so.

    It was these considerations that led STC and then Boeing to pursue a revision to their launch contract with the US government. The biggest sticking point, raised by the Astronaut Office in Houston, was the lack of an abort system on the crew pod to be carried within the Shuttle II payload bay. There was simply no identifiable survivable abort mode in the event of a second-stage breakup; even if the crew pod had the ability to independently reenter the atmosphere, it would have to break its way out of the Shuttle II payload bay first, requiring a complex system of explosives that would, most likely, damage the capsule itself on the way out. Boeing preferred instead to give its fully-reusable system a much more extensive flight-test program than any rocket but Sierra had received before, a flight test program much closer to that which their airliners underwent than any previous manned spacecraft. Though the astronaut office remained conservative, it eventually signed off when Boeing proved that the probability of a loss-of-crew would be the same or lower on Shuttle II as it had been on the original vehicle. With that issue settled, the Launch Contracting Office signed a revised contract with Boeing, allowing for the gradual phase-out of Lifter services from 2000 to 2002, and the reopening of manned flight service with Lifter II in 2001.

    The USAF took longer to persuade, and for time the service considered a new Complementary Reusable Launch Vehicle contract, allowing it to retain a Lifter and a set of S-IVD stages in storage in the event of a Lifter II stand-down. The biggest concern for that service was its fleet of KH-12 satellites and the manned craft that serviced them. Every few years, a replacement satellite did have to go up, even if the all-digital KH-12 had a nearly-indefinite orbital lifetime. Ultimately, they decided against that--as Boeing’s lobbyists argued, the Lifter would not be retired until Lifter II had completed a flight-test program that would certify it for airplane-like reliability. Once that happened, the risk of a Lifter II fleetwide stand-down became very small--even if a single vehicle failed, the rest of the fleet would not necessarily have to stand down. After all, even catastrophic aerial disasters did not ground the entire Boeing 747 fleet. Finally, even if the worst should happen and the entire Lifter II fleet had to stand down, the actual risk of losing satellite coverage was small. There were enough KH-12s in Low Earth Orbit to survive even the loss of a single satellite, and they could survive a delay in maintenance. The risk, Boeing argued, was manageable.

    For a while, the USAF still wanted to hedge its bets. The Gulf War and the later US interventions in Yugoslavia and elsewhere demonstrated the importance of real-time satellite reconnaissance in the modern battlefield, and the Joint Chiefs of Staff did not want to lose that critical advantage. However, as the National Reconnaissance Office’s budget shrank in the absence of the Soviet threat, the desire to not waste funds maintaining a mothballed Lifter I backup fleet overcame their caution, and the USAF agreed to shift to Lifter II launch services beginning in 2002.

    While Russia’s space companies worked to leverage their experience in space vehicles and human spaceflight to survive in the 1990s, Ukraine inherited the Soviet Union’s launch vehicle industry, and had to find a way to make that pay dividends in a world where the US, Japan, and Europe were all working to lower launch costs. While the Raskat-Groza system was partially expendable, low labor costs in Ukraine and at Baikonur helped keep the system’s launch costs noticeably lower than those of the American Space Lifter. That Russia’s military and civil space programs, even downsized, demanded dozens of flights per year helped even more by providing an economy-of-scale that reduced manufacturing costs for Groza even further. Unfortunately, the ‘brain drain’ problem that afflicted the entire former Warsaw Pact did not spare Ukraine--as the 1990s dragged on, young and talented Ukrainians tended to leave home in greater numbers, emigrating to Russia or Poland or the West, as the Ukrainian economy could not provide them with the standards of living to which they aspired, nor properly fuel their professional ambitions. Quality-control, never as exacting in the USSR as it was in the West, suffered noticeably after the demise of the Soviet Union, and a number of payloads were lost in the 1990s.

    Complicating matters was the fact that the Raskat-Groza upper stages were manufactured in Russia, not Ukraine, and the launch pads for the rockets were in Russia or in Kazakhstan, the latter of which negotiated a leasing agreement for individual pads at Baikonur Cosmodrome, allocating Sites 41 and 45 to Ukraine and 250 and 110/37 to Russia on a 20-year lease agreement. Launch services, then, had to be negotiated with at least two, and more often three, governments, a bureaucratic headache that made Western satellite builders reluctant to jump ship from Lifter to Ukraine (particularly with TPLI on the horizon, promising still-lower costs without the diplomatic complexities). More nationalistic Ukrainian politicians often condemned this dependence on Russia, but could not find a good solution for the problem--no launch pad in Ukraine could avoid sending payloads over Russia or another country, even if one were available, and money was scarce. A somewhat quixotic Polish proposal, wherein Raskat-Groza would be mated to a new Polish-built upper stage and launched off a converted oil platform (to be manufactured in Gdansk and towed to the mid-Atlantic) briefly gained traction but foundered on the lack of investor interest in Poland, and the fact that Poland had never built a rocket of such size (while Polish engineers at PZL Mielec insisted they could do as the Russian Kuznetsov Design Bureau had done and shift from turbojets to rockets easily, Ukraine’s engineers, remembering the difficulty with which NK-33 had come into existence, were more skeptical). Even so, the sheer number of rockets launched by Russia kept the Ukrainian launch industry afloat, giving the Ukrainians more time to seek foreign customers.

    The beginning of MirCorp operations was a boon to Ukraine’s launch vehicle industry, increasing the demand for Groza core stages and spare parts for the Raskat boosters (needed in greater numbers to launch the heavy Uragan orbiters) and providing a healthy infusion of capital to the Yuzhmash company. The added capital allowed Yuzhmash to invest in a heavier degree of automation of the Groza manufacturing process, reducing manufacturing cost while also improving quality control by eliminating dependence on skilled craftsmen who were, by the mid-1990s, retiring without replacement.

    Ukraine’s success in manufacturing and operating a reusable launch vehicle did not go unnoticed outside the country. As the European Space Agency ran into delays and budget overruns in the development of Alan Bond’s hypersonic air-breathing engine, a desire emerged for an interim booster for Europe’s LR program. Raskat, combining high-performance engines with a long history of successful recovery and refurbishment, was an early favorite, even though it was not manufactured in an ESA member state. The booster promised low development costs (as its use on the LR would require some modest structural changes for attachment to the hydrogen-burning LR core stage) and suggested a way to entice Ukraine to seek closer ties to the European Union and NATO, in the manner of the Visegrad Group. Though Ukraine’s government had been reluctant to antagonize Russia, the outbreak of the Chechnyan War in 1994 led to a reevaluation of Ukrainian foreign policy in Kiev. Combined with a sudden wave of corruption scandals, the Ukrainian government of Leonid Kravchuk was voted out and replaced with a new, Western-oriented government under former Yuzhnoye Design Bureau engineer Leonid Kuchma that emphasized a combination of the Shock Therapy reforms that were beginning to bear fruit in neighboring Poland and a focus on high-technology capital investment, which, according to their rhetoric, had propelled Japan and the other Asian Tigers to great heights. In this context, the proposal from Arianespace to Yuzhmash to modify Raskat as an interim booster for the LR found support among powerful officials in France, Germany, and Ukraine.

    With the LLOP deployed to its target orbit and happily sending back new Earthrise pictures every two hours, and LTV-4 on its way back to Earth, NASA gave the go-ahead to prepare for the first manned mission beyond Low Earth Orbit since 1972: ILP-3. Launching on February 24, 1998, the crew of ILP-3 would transfer from the Space Shuttle Discovery to their Hermes, carried in the Shuttle’s payload bay. Their craft’s callsign remained secret until they reached Low Earth Orbit, but when they did, and when the Shuttle arrived at the LTV-5/6 stack that would hurl them to lunar orbit, the first manned Hermes spacecraft, Challenger, presented itself to the world with a successful undocking from the Shuttle’s payload bay and an unsurprisingly flawless rendezvous-and-docking with LTV-6.

    For the first time since Apollo 17, a human crew rode a rocket’s column of fire through the Earth’s energetic radiation belts and out of the protective embrace of its magnetic field. Lighting up the evening sky over the Pacific with the familiar headlights-in-fog glow of a rocket in Low Earth Orbit, the four crewmembers, three Americans and one Russian, began their long journey back to the Moon.

    ILP-3 was a minor media sensation. Every day on the outbound flight, the entire crew gave a televised interview carried by the major American TV networks, while the Russian cosmonaut Sergei Avdeyev gave longer personal interviews on RIA Novosti, reflecting on his role as the first Russian to travel beyond Low Earth Orbit and emphasizing the enabling role of Russian biomedical research on Mir and the Salyuts and of Russian propellant launchers to the success of the International Lunar Program. However, it was, in many respects, a by-the-numbers mission. The Hermes, after all, had already had its shakedown on ILP-1, and the LTVs, by now, had a half-dozen missions under their collective belt. LLOP had verified its own power, thermal control, and communications systems a dozen times over since its own launch. The only real tasks for ILP-3’s crew were to verify the Hermes life-support system on a two-week cruise, to verify LLOP’s life-support systems for the few days they would spend in lunar orbit, and to test certain communication equipment that the Jet Propulsion Laboratory was developing for use on teleoperated lunar rovers that would take advantage of the low signal latency between LLOP and the Moon’s surface as it passed overhead. In other words, their job was to not die, and to not break the radio equipment before it had been tested. They in fact filled a great deal of their outbound flight with educational demonstrations videotaped for NASA’s education office to send out to schools across the United States. Still, crew morale was high during the outbound flight, and the (literally) otherworldly experience of gazing at the Moon from only one hundred kilometers away dispelled the tensions that had begun to build on the cramped voyage uphill.

    The teleoperation equipment passed its diagnostics tests with flying colors, to the relief of engineers at the Jet Propulsion Laboratory who were, in 1998, hard at work on the first American unmanned rover. Since the Apollo and Viking programs of the 1970s, JPL had lobbied for a mission to send large (several-hundred-kilogram) nuclear-powered rovers to the Moon and Mars, to follow up on the discoveries made by the J-Class Apollo missions and the stationary Viking landers. The Soviet Union’s Lunokhod program had proven the concept, as had the manned Lunar Roving Vehicle packed on the last three Apollo missions, but with NASA’s attention focused firmly on the Space Transportation System and enthusiasm for Mars surface exploration at its nadir following the inconclusive results of Viking’s biological experiments, the idea had never caught on. The Space Exploration Initiative had breathed new life into JPL’s efforts, as the new focus on the Moon and Mars--the only near-term destinations for human explorers--brought with it a new interest in funding for robotic missions to blaze the trail. Following the successful orbital insertion of the Mars Observer spacecraft in 1993, Congress approved for NASA’s FY1994 budget the Planetary Rover Program, as a complement to the Observers.

    In accordance with Dan Goldin’s “Faster, Better, Cheaper” slogan, the Planetary Rovers would rely on a common bus developed for both the Moon and Mars, to encourage some degree of mass-production and to minimize development time between funded missions. The Rovers would all have a mass, depending on payload, of between 500 and 550 kilograms, which would allow them to land on Mars using Viking-heritage landing systems or on the Moon using a lander fueled by a single LTV stack. As JPL’s engineers worked longer on the Planetary Rover design, they settled on a configuration that they believed would suffice for any near-term planetary environment: each rover would consist of a single chassis, equipped with a rocker-bogie suspension system, a platform on the rear bed on which different power supply systems (RTGs or solar arrays) could be mounted, a robotic arm, and a camera mast, both of which could mount a variety of scientific instruments.

    In an interesting deviation from traditional American spacecraft, the specified power source for the Lunar and Planetary Rover series was neither photovoltaic panels nor plutonium RTGs, but new RTGs designed to use strontium-90. The cessation of American plutonium-238 production in 1988 made the latter material a valuable commodity, one that NASA preferred to hoard for missions to the outer planets, where plutonium-238’s very long half-life was crucial to maintaining a spacecraft for the many years it would take simply to cross the vast interplanetary gulf. While strontium-90 had a lower power-density and half-life than plutonium-238, it was far cheaper than the heavier isotope, as it was produced as a waste product in commercial nuclear reactors, from which it was already commercially harvested for use in radiotherapy. The Department of Energy’s acquisition of a license to copy a Soviet strontium-90 RTG design streamlined the change-over at NASA, freeing at least some of the agency’s planetary exploration dreams from the logistical constraints plutonium imposed.

    The first such rover was planned for deployment with the first LSAV, scheduled for early 1999. Though Martin-Marietta had brought their considerable experience to the table, the lander’s broad outline still closely resembled the design that NASA outlined in 1995: a ring of spherical propellant tanks, wrapped up in foil insulation, encircling a pair of Lunar Transfer Main Engines. Atop the propellant tanks was an aluminum mesh platform with a folding ramp, to which payloads could be bolted. Four spring-loaded legs marked out the corners. The entire spacecraft was just over 6 meters in diameter, which meant it could not be retrieved in the Space Shuttle payload bay, though it could be fit into the Sierra payload bay. For the moment, NASA had no plans to return a LSAV to Earth; all servicing on that vehicle would be performed at the LLOP.

    The original NASA plan for testing the LSAV had called for an Earth-orbit demo flight prior to the actual first mission to the Moon. However, the LSAV’s ground testing program (particularly tethered landing tests at the Space Power Facility near Sandusky, Ohio) had been so straightforward that the decision was made to condense the first two missions into one and excise the planned quiescent period in Low Earth Orbit between missions. As a result, the ILP-4 mission would see not only the first flight of the new LSAV, but its voyage directly to the Moon’s surface and then back to Low Lunar Orbit.

    Launched on February 2, 1999, the first LSAV, named “Albatross” after the migratory bird renowned for its endurance and the distances it travelled, and as an homage to the Lunar Modules Eagle and Falcon, was launched with its lunar rover payload by the Space Lifter Independence. Albatross was put through her paces in Low Earth Orbit, deploying and retracting her landing gear, maneuvering in formation with her S-IVD, transferring propellant back and forth to a small extra tank mounted to the forward end of that stage, and, finally, burning her main engines just long enough to prove that the design already validated on the LTV was still functional. With that done, Albatross departed her booster and chased down her waiting LTV stack (LTV-1/2, Siegfried and Roy), which carried her on the next leg of America’s return to the lunar surface.

    After a (by now) routine transfer to Low Lunar Orbit, Albatross separated from Roy and took her first independent flight around the Moon. Her first destination was the LLOP, where she autonomously approached the small space station until the platform’s robotic arm latched onto her flank, bringing her into an unpressurized berthing port on the LLOP’s nadir side. The arm then performed an all-around inspection with high-definition cameras, beaming back signals to Earth. Though TPLI had built a support framework so that it could fit into Sierra’s payload bay, the cost of shipping the LSAV back to the Moon from Earth was high enough that NASA had no desire to ship it down as often as the LTV’s had been during their testing program. Its main moving parts--the LTMEs--had racked up many hours of flight time and hundreds of hours on the test stand before Albatross ever took flight, and the LTVs had proven remarkably resistant to damage from radiation, micrometeorites, and the variable thermal environment in space. Though the LSAV was taking the next small step, both NASA and its contractors were confident enough in its durability that its first few inspections would be done at the LLOP, in orbit around the Moon.

    Fortunately, neither the spacecraft’s diagnostics instruments nor LLOP’s visual inspection revealed any obvious flaw with Albatross, and when the spacecrafts’ orbit around the Moon precessed far enough, NASA and JPL gave the authorization to undock from the LLOP and begin America’s first descent to the Moon in over twenty-five years.

    Like the Apollo planners before them, the planners at JPL for the first Lunar Rover mission had to balance accessibility with scientific value when choosing their landing site. They had the added complication of having to choose a site of secondary interest, so as not to waste resources by going to a site slated for a manned visit. In effect, they had to choose a site that was interesting, but not at the top of most geologists’ wish lists.

    Luckily, they had new information at their disposal for which their forerunners might have killed. The Lunar Observer satellite, which had entered lunar orbit in 1994, had revealed new and surprising information about the Moon’s chemical composition, indicating that a strange mix of elements called “KREEP” (for Potassium, Rare Earth Elements, and Phosphorus) was mostly present in two regions on the lunar near side--in Oceanus Procellarum, the Ocean of Storms, and Mare Imbrium, the Sea of Rains, the (relatively) new impact crater on top of it. Geologists were eager to study these terrains up-close, to get at a reason for that concentration, and to perhaps find the reason for the great dichotomy between the Moon’s far and near sides. Why, after all, must almost all the lunar seas be on the Near Side?

    Many of the sites with high KREEP concentrations, like the craters Aristarchus and Copernicus, were already slated for manned missions, but there was no shortage of regions of interest for the first Lunar Rover. Ultimately, JPL settled on the Montes Jura, the rugged mountain range around the Bay of Rainbows (Sinus Iridum) at the north-west corner of Mare Imbrium, a region that the Lunar Observer’s spectrometers had indicated was high in thorium and other rare-earth elements, suggesting an abundance of KREEP.

    It was toward the Montes Jura, the furthest point from the Moon’s equator that any spacecraft, manned or unmanned, had ever visited, that Albatross descended, carrying her still-dormant cargo. Approaching from the north, over the rugged terrain around the Moon’s north pole, she had de-orbited herself and fell most of the way down toward the Moon, in a sweeping elliptical orbit that just happened to pass within the Moon’s surface. As she approached her final destination, the lander relit her engines, cancelling almost all of her velocity, narrowing that ellipse ever further until it was almost a straight line between herself and the Moon’s core. As engineers at JSC, JPL, and Martin-Marietta held their breath, she beamed back crystal-clear video of her descent, the colors of the Moon resolving from their light-and-dark-grey appearance to a collection of tans and browns and greys, terrain sculpted only by volcanism and meteorite impacts once again receiving visitors from the world of wind and water.

    Soon after the Bay of Rainbows, the broad, flat plain south of Albatross’ landing site, slipped below the Moon’s near horizon, the lander was in its terminal descent. Her two engines had throttled back as far as they could, blasting only a thin wisp of smoke and steam down to the Moon, as her radar altimeter counted off the last few meters until she touched down.

    When she at last lit upon the Moon’s dusty surface, it was almost an anticlimax--her terminal descent had been so gentle that the only indication of landing was a contact light going off on her support team’s consoles, over a second after the fact. It took a moment for the reality to sink in, that for the first time since Apollo 17 the US had soft-landed a payload on the Moon. Mission Control in Houston exploded in a celebration that lasted a good hour, though not everyone could join in--some engineers had to remain at their desks, watching Albatross’s telemetry and that of the Lunar Rover, ensuring that nothing critical had broken on the way down, that the payload was in shape to roll out.

    After a 6-hour checkout period, Control gave the order for Albatross to unfold her ramp, and for the Lunar Rover to unfold its six robotic wheels. In total silence, an aluminum mesh descended to the Moon’s surface, forming a 45-degree ramp (insanely steep by Earth’s standards, but safe enough in the Moon’s weak gravity) down the three meters that separated the Rover from her destination. Then the Rover came to life, unfolding her six wheels, extending her radio and television masts, pointing her high-gain antenna at Earth (and communicating with the LLOP through her short-range omnidirectional antenna), and giving each of her moving parts a diagnostic spin before she could actually begin her mission.

    When JPL was satisfied that she had made it from the Earth to the Moon intact, they sent her commands to roll down the ramp. In almost real-time, they watched as the Moon came up to meet the rover, until the television camera gave a light jolt when the wheels met the dust and the rover’s suspension absorbed the impact. Once her six wheels were all on the Moon, the real work began.

    Over the course of her mission to the Montes Jura, Lunar Rover 1 would set new records in planetary rover endurance and range. During her first lunar day, she only drove one kilometer, but as her operators gained confidence in themselves and in the new machine, they pushed her farther. On her fourth lunar day, she drove almost 17 kilometers, breaking Lunokhod 2’s record of 16.5 kilometers in a single day. Her travels took her from the level of Sinus Iridum to the heights of Point Laplace on its eastern “shore,” and her geological instruments greatly improved scientists’ understanding of the distribution of rare minerals on the Moon’s near side. Daily updates on her progress became the single most popular feature on NASA’s website, despite the agonizingly slow download times necessary to download the immense, multi-megabyte photographs, and her lunar sojourns would become the basis for a very successful IMAX film, shown in aerospace museums across the United States even a decade after her landing.

    Most relevant to later lunar missions, though, was an experiment carried out by the ILP-5 crew during the Rover’s third “day” on the surface (two months after landing). During the 10 minutes they were within line-of-sight of the Rover, they communicated with it and controlled it directly from the LLOP, demonstrating the principle of teleoperation--the control of unmanned vehicles from a manned spacecraft. While this was not necessary for operations on the lunar near side, teleoperation made possible lunar rover missions to the far side, or to other regions that could not maintain a line-of-sight to Earth. It was also during the ILP-5 mission that the LLOP acquired its unofficial call-sign: “Collins Base.”

    The second lunar rover mission would go on to prove the utility of teleoperation, when the crew of ILP-7 teleoperated the first spacecraft sent into the Moon’s South Pole-Aitken Basin. Since the Lunar Observer spacecraft had hinted at the presence of ice in the permanently-shadowed craters at the southernmost parts of the immense crater, the focus of engineers designing In-Situ Resource Utilization (ISRU) systems had shifted from baking lunar rocks at immensely high temperatures to the much easier task of electrolyzing water. However, before any of those plans could be brought to fruition, it was first necessary to prove that the ice existed at all. Lunar Rover 2 (dubbed “The Buzz Bot” after the last Apollo 11 crew member, who had not yet had a new vehicle named in his honor) would do just that, providing the first in-situ look at the Moon’s hidden hoard of cometary scraps.
     
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