“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.
