The Cape, Chapter 4, Section 1
The Cape, Chapter 4, Section 1
On 25 February 1985, President Ronald Reagan signed National Security Decision Directive 261, "Recommendations for Increasing United States Heavy-Lift Space Launch Capacity." The document articulated the need for a national space transportation study, and it directed the Defense Department and NASA to get together to study the development of a second generation space transportation system employing both manned and unmanned launch systems in the post-1995 era. Another directive entitled "National Space Transportation and Support Study (NSTSS)" followed on 14 May 1985, whereupon a joint NASA/Defense Department steering group was established to begin the work in earnest. The steering group was co-chaired by Mr. Jesse W. Moore (NASA's Associate Administrator for Space Flight) and Air Force Under Secretary Edward C. Aldridge, Jr. The principal objective of the study was to identify alternative launch vehicle technologies considered necessary or "prudent" to pursue for the U.S. space program after 1995. The study was also expected to identify potential space mission classes of vehicles, assess support capabilities and discuss "non-vehicle specific technologies" that would help develop the vehicles and support systems needed after 1995.1
As its first task, the NSTSS Joint Steering Group was directed to compile a set of potential space mission classes. Its second task involved trade studies, systems analyses and technology assessments to define space transportation options for two sets of space missions-military and civilian. A third task required the identification of technology investment strategies that might "revitalize the nation's launch technology base." The Steering Group's fourth task was to identify technology development programs that could make the entire process pay off at the appropriate time. Though this was a joint effort, the civilian part of the study would be published apart from the Defense Department study to ensure that overlapping needs and differences between military and civilian missions were identified explicitly. On 13 June 1985, a NASA/Defense Department Joint Study Group was set up under the direction of Mr. Paul Holloway and Colonel William F. H. Zersen to implement those civilian and military studies. The Civil Needs Working Group (under the Joint Study Group) published Volume I of the Civil Needs study on 30 October 1985. The Joint Study Group produced a draft of its National Space Transportation and Support Study in May 1986.2
In its October 1985 study, NASA noted that the mid-to-late 1990s offered the nation an opportunity to shift from the Space Shuttle to a low-Earth orbiting space station. The space station was seen as the "cornerstone of an expanding space infrastructure" which could include co-orbiting unmanned platforms as well as polar and geosynchronous unmanned stations. The study also suggested possible landmark missions in the 21st Century, including a manned geosynchronous space station, a habitable lunar base and a Mars sample return. Such missions would require routine inspection, servicing and repair of spacecraft, the assembly of large space systems, the use of Orbital Transfer Vehicles (OTVs) for routine cargo management in space and (most importantly) rapid and effective development of technology to make the entire space infrastructure workable. It must be emphasized that the study presented those ideas on the premise of an expanding space program, not the U.S. space program as it was funded when the study was published.3
The draft of the National Space Transportation and Support Study went further. Since the level of space operations in the 1995-2010 period was difficult (if not impossible) to predict in 1986, the Joint Study Group's Mission Requirements Panel developed four alternative sets of mission needs which were presented as five combinations of mission models labeled "cases." Case 1 presented a very modest civilian space effort and a constrained military space program. Case 2 was a normal growth program. Case 3 combined the Case 2 scenario with a modest expansion in the civilian sector and a "representative" deployment of SDI kinetic energy weapons. Case 4 combined the Case 2 civilian program with a full-blown SDI program, and Case 5 combined the Case 2 military program with an aggressive civilian space program. Apart from the five case scenarios, the Joint Study Group agreed that, if nothing new was done, the U.S. would enter the late 1990s with: 1) a modest Space Shuttle fleet, 2) TITAN IVs to assure a launch capability for critically important Defense Department missions and 3) a limited launch and spacecraft processing capability. Even under Case 2 conditions, the old space transportation architecture would have a hard time meeting normal growth requirements after the turn of the century. By the year 2005, the first-generation Shuttles would be at the end of their operational life cycles. Several more Shuttle orbiters and many more unmanned vehicles would have to be purchased together with additional support facilities. Despite billions of dollars of additional investment, technological advances would be slow, and the operational savings would be modest.4
The Joint Study Group believed there were several alternatives to the existing space transportation architecture. The Unmanned Cargo Vehicle (UCV) and a second-generation Space Shuttle were proposed as twin centerpieces in a modernized space program. Three options were presented in the May 1986 study. Option A included a new partially reusable UCV in the mid-1990s, a partially or fully reusable new upper stage in the late 90s and a Shuttle II vehicle around 2002. Option B included the features of Option A plus a payload return capability featuring payload canisters, a payload glide housing or a fully reusable second stage with a cargo bay. Option C also reflected the characteristics of Option A, but it included modularized elements for the UCV to make deployment of a full-blown SDI network more cost-effective. Elaborating on its investment strategy, the Joint Study Group presented three architectures keyed to options A, B and C. Architecture 1 suggested use of first-generation Space Shuttles through 2002. The Shuttle II vehicle would pick up the manned space mission after 2002, and unmanned payload requirements could be handled by a 150,000-pound payload capacity UCV. Architecture 2 would have the UCV mentioned in Architecture 1, but it would also have a fully recoverable booster and a partially recoverable upper stage. Architecture 3 featured Shuttle operations through 2001, followed by Shuttle II operations beginning in 2002. From 1995 through 2008, Architecture 3 called for a 150,000-pound payload capacity UCV with a payload deorbit capability as well as a launch capability. To provide greater cost-effectiveness, the UCV would be equipped with a fully reusable first stage booster in 2008. Though the annual investment in any one of the three architectures could run as high as $7 billion, the Joint Study Group believed that all three showed lower life cycle costs than the existing fleet of Shuttles and unmanned launch vehicles. The Group deemed Architecture 2 the most cost-effective alternative. Architecture 1 was considered the least cost-effective choice.5