Well, it's that time once again. Last week, we dealt with the various international flotilla of probes head to Halley's Comet. This year, we're turning to something equal international, but perhaps less desirable: global thermonuclear war, or perhaps more specifically the question of defending against it. That's right, this week we're talking about
Star Wars. Hang on, I'm being informed by our culture desk that...oh, I see, different Star Wars? Ah. Well then. On with the show anyway!
P.S. Production update: buffer is now complete through the end of the year, with 57,000 words currently written in total for Part II. 5 posts remain to be completed, and we are now beginning to simultaneously work on elements to complete Part II and start Part III. In fact, my reward to myself for finishing the post that's queued up for next week was getting to write a post for Part III following up on something revealed in this post.
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Eyes Turned Skyward, Part II: Post 13
Since the Soviets had developed their own nuclear capability and ICBMs in the 1960s, the dominating doctrine in the field of nuclear weapons deployment had been one of Mutually Assured Destruction, or MAD. Under the tenants of MAD, while it was possible to launch a strike sufficient to destroy an enemy, the Soviet and American’s respective bombers, missile silos, and missile submarines created a nuclear trident, which would be able to react to an attack if one were started and respond in-kind before the attack struck home, meaning that any attempt to destroy the enemy would lead to one’s own destruction. Therefore, the most important role for nuclear forces was to maintain that “second-strike” capability, while at the same time preventing accidental use of nuclear weapons, ensuring that any attempt on the part of the enemy to attack would be suicidal. However, many in the military viewed this doctrine negatively, as it was based on the assumption that nuclear weapons were impossible to intercept and their damage had to be accepted as part of a stalemate, both assumptions that chafed for minds more used to an interplay of offense and defense, in which neither had an absolute upper hand. Thus, studies aimed at methods for intercepting ICBMs--the most intractable, so far as defense was concerned, of the trident--in-flight had been under study since the late 50s, mostly focusing on anti-ballistic missiles to intercept during descent. However, new technical developments in the late 70s--mainly new variants of the laser--had created a new possibility that suggested a new doctrine, this time one of strategic defense.
The new weapon, the X-ray laser, was a pet project of Edward Teller, the father of the hydrogen bomb, though it was actually developed at Livermore National Labs in 1977 through 1980. The lab’s O-group had, through several revisions, demonstrated that a proper focusing crystal (actually a metal rod) could be “pumped” with the X-rays created by the energy release of a nuclear detonation to create a high-power laser. The “Dauphin” test in November 1980 had proved that the concept was potentially viable, and a further series of tests was planned under the name “Excalibur” to refine the concept. Compared to more conventional directed energy weapons, like chemical lasers, bomb-pumped lasers had two benefits stemming from their extremely high power density. First, they packed enough energy that the dwell time required to destroy a target such as a launching ICBM would be very short--perhaps as small as ten seconds. Second, their light weight made them potentially ideally suited to mounting on space-borne platforms, which could provide constant coverage over Soviet launch sites. By intercepting the missiles during launch, the benefits of multiple independent re-entry vehicles could be neutralized, and thus it was potentially possible for a constellation of laser satellites to be built which could intercept any Soviet nuclear strike. The idea had tremendous appeal for Teller, who had long promoted alternative uses of nuclear technologies, such as for excavation of entire harbors or canals, and he became a strong advocate of the project.
President Ronald Reagan had also been dissatisfied by the doctrine of MAD, and found the notion that, while individual missiles and re-entry vehicles could be tracked all the way to their targets, they were unstoppable in-flight to be unbelievable. Besides that, he had a strong personal antipathy to the notion of nuclear war and its apocalyptic consequences. Thus, he directed his advisors to investigate options for a new doctrine, using technologies like the X-ray laser, as well as a variety of more conventional weapons, to render ICBMs and their warheads vulnerable in-flight. For the first year of his Presidency, this activity largely confined itself to studying the range of ABM weapons that had been researched or developed since the development of the ballistic missile itself, searching for a system or systems that could actually protect the US against nuclear attack, and perhaps it would have remained there had it not been for the development of Vulkan and the consequent light it shone on all types of space activity.
Vulkan’s appearance led to a wholesale reevaluation of not only civilian but also military space programs and priorities. Although the development of a rocket with similar capabilities had been suspected through the NRO’s observations of Baikonur Cosmodrome, observations which played a significant role in the decision to adopt the Saturn Multibody for ELVRP II, satellites could only provide generalities, not the detailed technical information available from watching launches. And what those launches revealed was a set of vehicles that in many ways seemed to exceed present Soviet needs, indeed to go far beyond them. What could, intelligence analysts wondered, induce the Soviets to spend so much treasure and effort on building such a capable system?
The obvious answer would be expanding Soviet military capabilities in orbit, and as a result of research undertaken since the middle of Carter’s term, nuclear war experts in the government thought that they had a good idea of what, exactly, those military capabilities would be: anti-ballistic missile weapons. In particular, Vulkan would be ideal for launching “Excalibur”-type platforms into orbits covering US ICBM fields, and its larger variants could lift some of the heavier, more conventional weapons to provide further defense capabilities. Vulkan could also theoretically be used to launch “hardened” satellite platforms to fulfill existing Soviet missions through a combination of improving Soviet technology (reducing the weight of payloads) and increased lift weight, together compensating for additional protection against American anti-satellite attacks. Although emplacing nuclear weapons in orbit was and remains illegal under the Outer Space Treaty, and any ABM system capable of protecting an entire nation
ipso facto violates the ABM Treaty, both sides had routinely violated solemn international agreements during the Cold War, and for objects much less impressive and potentially valuable than a functional missile shield. The only possible US counter, according to this line of analysis, would be its own missile defense program—a vastly expanded form of the lackadaisical efforts up to that point, with a clear mission: protecting the US against Soviet attack. The fact that most of the systems that had been proposed for missile defense also offered opportunities for attacking enemy satellites, often with far more efficacy than in the defense role, surely played a further factor in this particular reasoning, which quickly became received wisdom within the US intelligence and defense establishments.
In May 1982, just three months after the first Vulkan launch and well within the Vulkan Panic, President Reagan chose to address a speech to the nation “on the national defense”. In the course of this speech, he outlined the two policies which, so far as space was concerned, would define his Presidency. First, he sought to allay concerns that the Soviet Union was overtaking the United States in space technology, both by pointing towards ongoing and significant American achievements in space, and by announcing the development of Space Station Freedom, a much larger and more capable space station than either Spacelab or Salyut 7 (or, as matters would unfold, the MOK that was then being developed behind the Iron Curtain). Second, he pointed towards the fact that space could not only threaten but shield the United States; far from being a Communist menace, it could be made the protector of liberty. As such, he announced that he would start a program to permanently end the menace of nuclear weapons and the ballistic missiles used to carry them, the Strategic Defense Initiative. Although he spoke only in generalities, he made clear the potential of advanced technology and spaceflight to render the nation completely safe against nuclear weapons, a cause the President passionately believed in.
While responses to the speech were mixed—by the November midterm elections, the Vulkan Panic had ebbed somewhat, and Republicans took a drubbing based on their handling of the economy—this nevertheless marked the beginning of an enormous R&D program which, in essence, had two parts, at least so far as the space-based components were concerned. First were the actual weapons platforms and their supporting infrastructure in space. Besides the weapons themselves, observation satellites, communications platforms, and command-and-control posts would need to be developed and built, all capable of working together largely autonomously to defeat what, in a full-scale nuclear war, could be thousands or tens of thousands of Soviet missiles and warheads, a formidable task even without the additional complications of having to develop the weapons from scratch. These systems would also all need to be maintained in space, a further item of significant difficulty (and a secret motivation behind Freedom). Second were the methods of launching these platforms and satellites into space. Although ELVRP had developed a pair of vehicles in many ways much advanced over their predecessors, it had neither been intended nor capable of developing vehicles with the kind of capabilities that early analyses indicated were necessary for SDI. To avoid incurring massive expenditures merely on launches, costs would need to be brought down significantly, ten-fold or more, while capacities would need to remain similar, since the larger chemical laser satellites and possibly the Excalibur platforms would need large vehicles, similar to the solid boosted Saturns or even the Saturn Heavy for launch.
Four approaches for space-based ABM weapons were identified in the full-scale review of the “defense problem,” intended to synthesize all existing information about ballistic missile defense into a single strategic outline of what, exactly, SDI would need to do to achieve its mission as being probably the most worthy of significant attention. The first was Excalibur’s bomb-pumped lasers, which despite some disappointing test results still seemed to offer the most overall promise. Although vulnerable, like all space-based weapons, to ground attack, and blocked by the atmosphere (a problem if the Soviets developed rapidly burning ICBMs that could complete their rocket boost without entering space), the Excalibur concept still offered the most overall capability of any of the space-based weapons studied, and the possibility of use as a ground-based intercept weapon, perhaps based on modified SLBMs. The second were lasers, possibly the most conventional of the directed energy weapons discussed. Whether based in space or using mirrors in space to redirect US-based beams towards Soviet missiles, these shared the problems of vulnerability to anti-satellite attack and targeting common to most space-based weapons, while adding the issues of heat and power output for the space-based version and atmospheric interference for the ground-based variant. The third type of weapon, the particle beam, envisioned basing large particle accelerators in space, firing hydrogen atoms at very high speed at enemy ICBMs. Although probably not capable of physically destroying ICBMs like Excalibur or the conventional lasers, the radiation produced by energetic protons impacting ballistic missiles could damage or destroy the sensitive electronic components needed for the missile and its weapons to properly function. However, like Excalibur’s x-ray lasers, particle beams could easily be blocked by the atmosphere, and it would be difficult to confirm that target missiles were actually destroyed or disabled. Finally, there were kinetic energy weapons, essentially masses strapped onto rockets and fired at enemy missiles. The oldest and best developed approach, these suffered from limited velocities, and consequently limited range. Although methods could be developed of partially overcoming this limitation, these would have their own drawbacks, mainly increasing the cost and complexity of the interceptor. Together with the necessary targeting, communications, and control satellites, these four weapon types absorbed the vast majority of SDI research funding, as without some functional method of missile intercept all the rest would be useless.
As for the launch cost problem, three possible approaches quickly became apparent. The first and conceptually the simplest would be to just improve existing launch vehicles—a sort of ELVUP, building on the success of ELVRP I and II. However, it seemed doubtful that merely modifying existing vehicles would lead to the sorts of large cost savings necessary, and this approach received relatively little attention from SDI. The second approach, which proposed the development of a highly reusable vehicle much like the Shuttle briefly mooted in the late 1960s before the direction of NASA efforts into space stations, was far more popular among members of the SDI team. While less simple, it was also a conceptually obvious approach for improving launches. Intuitively, the launcher is a complex, expensive vehicle, and launcher manufacture absorbs most of the cost of a space launch. By not expending the launchers as if they were artillery shells, but reusing them as if they were airplanes, great cost savings could theoretically be had. Advocates liked to describe the disposable approach as similar to building a 747 (or other jetliner) at the airport for each flight, then scrapping it at the destination. The third and final approach was perhaps the most interesting, proposing instead the construction of extremely cheap disposable launch vehicles as the way to go. By using cheap, easy to store fuels, large thrust-to-weight ratios, and mass production or well-proven building techniques (depending on which advocate you talked to), this could achieve the same cost reductions as the second approach without requiring an extensive and expensive R&D program, or exotic and difficult engineering techniques.
As the most overall promising of the three from a theoretical standpoint, the second approach received the lion’s share of the funding allocated for SDI space launch research. This was further divided into two programs, the X-30, which (based on a flawed calculation) envisioned the development of a scramjet-rocket hybrid aircraft that could takeoff from a normal runway and fly into space with an acceptable cargo, and the X-40, based on Phil Bono and Gary Hudson’s work over the previous two decades, which instead envisioned a purely rocket-powered vehicle that would take off and land vertically. While X-30 work focused on materials science, to produce the light and strong materials needed to make the approach work, the X-40 focused mostly on showing that a pure rocket vehicle could actually fly, maneuver, and land. To this end, proposals were solicited for a test program consisting of two subscale prototype vehicles, able to be flown regularly to test control and operational procedures for a vertical takeoff, vertical landing (VTVL) reusable launch vehicle. Grumman, which had been slowly recovering from its financial near-disasters of the 1970s, managed to leverage its heritage as a DoD contractor and the developer of the Lunar Module during Apollo into a winning proposal.
The X-40 was designed around four RL-10 hydrogen/oxygen engines, with control to be provided through a combination of engine gimbal, gasous oxygen/gaseous hydrogen thrusters, and aerodynamic control surfaces. To ensure the rugged qualities the program called for and mitigate the amount of technical development required, the Grumman engineering team selected conventional aluminum structures, instead of the advanced composites being researched for the X-30. Additionally, in the same tradition which had lead to Grumman being dubbed the “Ironworks” during WWII, the X-40 (internally nicknamed the “Starcat” by Grumman engineers) was also designed with robust margins and an eye towards ease of ground handling, even at the expense of additional weight--many senior Grumman engineers recalled the operational headaches of leaks and welding created by the need to trim weight from the fuel systems on the lunar module, and (given the relatively low delta-v required of the X-40 vehicles) sought to avoid such headaches on the X-40. Thus, after two years years of design and development, construction of the first spaceframe began at their Bethpage, Long Island facility in 1987. By 1990, while the X-30 program (which many had regarded as more promising in 1984) continued to encounter setbacks with the proposed scramjet engines and advanced materials, leaving it stalled at basic design, the first Grumman X-40 was being prepared for transport from Bethpage to White Sands to begin flight testing.
- which did have an effect on NASA IOTL. Though it seems here, it the effect has been magnified, no doubt by the Freshness of the Vulkan-Panic just as Space was heading up Reagan's Agenda. 