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It was clearly not possible to build a single-stage-to-orbitvehicle with the technologies of the day.8In 1962, in an effort to save the reusable concept, Air Force designers turned to a twostage design for a concept they began to call the Aerospaceplane. Seven aerospace companies received contracts for the initial design.9 Through these and several follow-oncontracts, the companies not only produced paper studies, but undertook research onramjet and scramjet propulsion, explored new structures and materials, and made significant advances in understanding hypersonic aerodynamics. However, reality never livedup to the designers’ aspirations. By October 1963, after watching the Aerospaceplane program for some time with concern, DOD’s Scientific Advisory Board reached the conclusion that the program was leading the Air Force to neglect conventional problems inlaunch research.10 The Aerospaceplane program was quickly shut down.NASA also sponsored a series of studies investigating reusable concepts for a variety of crewsand payload sizes.
By June 1964, NASA’s Ad Hoc Committee on Hypersonic Lifting Vehicleswith Propulsion issued a report urging the development of a two-stage reusable launcher.11During the early 1960s, under government sponsorship, all of the major aerospacecompanies also developed their own version of a two-stage launch vehicle employing a lifting-body reentry vehicle. In each of these studies, the industrial concerns depended to ahigh degree on NASA and the Air Force to furnish the initial configuration on which tobase their own version.
The firms were concerned about straying too far from the conceptsthat their government “customers” were promoting.12 This continued the practice evidentin Project Mercury, in which the government agencies not only set the design goals and laidout the technical specifications but also instructed industry how to achieve them.Origins of the Space Shuttle ProgramNo single action or decision similar to President Kennedy’s May 25, 1961, “we shouldgo to the moon” speech marks the beginning of the focused NASA program to developthe Space Shuttle. Rather, the program emerged over time in increments while NASA wassimultaneously completing work on the Saturn V and launching the Apollo astronauts tothe Moon and back.
By the time President Nixon made the 1972 decision to proceed withSpace Shuttle development, most major aspects of its design had been set.137. A scramjet (supersonic combustion ramjet) is an engine in which air compression, fuel mixing, andcombustion all occur at supersonic speed.8. Some even advocated refueling the Recoverable Orbital Launch System in hypersonic flight, using theX-15 to validate the concept. Fortunately, this extremely risky and dangerous concept was never tried. SeeRichard P. Hallion and James O.
Young, “Space Shuttle: Fulfillment of a Dream,” in Richard P. Hallion, ed., TheHypersonic Revolution: Eight Case Studies in the History of Hypersonic Technology, Volume II (Dayton, OH: WrightPatterson Air Force Base, Special Staff Office, Aeronautical Systems Division, 1987), p. 948.9. Boeing, Douglas, General Dynamics, Goodyear, Lockheed, North American Aviation, and Republicreceived contracts for system design studies. General Dynamics, Douglas, and North American received fundingfor detailed development plans. Martin built a full-scale model that explored the concept of incorporating thewings with the fuselage.10.
Hallion and Young, “Space Shuttle: Fulfillment of a Dream,” p. 951.11. Report of the NASA Special Ad Hoc Panel on Hypersonic Lifting Vehicles with Propulsion, June 1964.See also the memorandum from Floyd L. Thompson to James Webb, June 18, 1964. Copies in the NASAHistorical Reference Collection, NASA History Office, NASA Headquarters, Washington, DC.12.
“In each case, whether dealing with Air Force-inspired configurations or NASA-inspired ones, contractors generally danced to an Air Force or NASA tune as regards the overall configuration itself.” Hallion andYoung, “Space Shuttle: Fulfillment of a Dream,” p. 957.13. See Logsdon, gen. ed., Exploring the Unknown, 1: 386–88.****EU4 Chap 2 (161-192)1644/2/0112:45 PMPage 164DEVELOPING THE SPACE SHUTTLEAs early as August 24, 1965, more than two years before the first Saturn V rose from thelaunch pad, the Air Force and NASA established an Ad Hoc Subpanel on Reusable LaunchVehicle Technology under the joint DOD-NASA Aeronautics and Astronautics CoordinatingBoard.
Its objective was to determine the status of the technology base needed to support thedevelopment of an RLV. The report, which was issued in September 1966, concluded thatmany cost and technical uncertainties needed to be resolved, but it projected a bright futurefor human activities in Earth orbit. [II-1, II-2] Because the panel could find no single launchconcept that would satisfy both NASA and DOD, it included ideas for a variety of fully reusableand partially reusable vehicles. Interestingly, the panel projected that partially reusable vehicleswould be much cheaper to develop than fully reusable ones. Even so, engineers within bothNASA and the Air Force continued to focus on fully reusable launch systems for several years,in the belief that once the difficult design and development problems were solved, such systems would prove much less costly to operate.14 Some designers favored fully reusable designsthat would employ a reusable booster and a cryogenic-powered orbiting vehicle.
Others feltthat the surest path to success was a small lifting body mounted on top of an expendable launchvehicle, such as a Titan III. Other design concepts lay between these two extremes.As NASA began to think in depth about its post-Apollo human spaceflight programsafter 1966, its top-priority objective became gaining approval for an orbital space laboratory—a space station.
NASA planners also began to recognize that there was a need toreduce the costs of transporting crews and supplies to such an orbital outpost if it was tobe affordable to operate. This, in turn, led to a focus on an Earth-to-orbit transportationsystem—a space shuttle. The idea that such a vehicle was an essential element in whatever might follow Apollo was first publicly discussed in an August 1968 talk by NASAAssociate Administrator for Manned Space Flight George Mueller.
[II-3]In December 1968, as planning for the post-Apollo space program gained momentum, NASA convened the Space Shuttle Task Group to determine the agency’s needs forspace transportation. [II-4] This task group set out the basic missions and characteristicsof the kind of vehicle that NASA hoped to gain approval to develop. Through the MannedSpacecraft Center and Marshall Space Flight Center, the Space Shuttle Task Group in mid1969 issued a request for proposals (RFP) for what it termed an Integral Launch andReentry Vehicle (ILRV) system. The RFP specified an emphasis on “economy and safetyrather than optimized payload performance.”15 The eight-month studies that resultedformed the beginning of the Space Shuttle Phase A study effort.16 Four aerospace contractors won ILRV study contracts—General Dynamics, Lockheed, McDonnell Douglas,and North American Rockwell.The Space Shuttle Task Group final report, issued in July 1969, concluded that anILRV should be capable of:••Space station logistical supportOrbital launch and retrieval of satellites14.
In the 1980s and 1990s, the goal of achieving vastly cheaper operational costs continued to eludedesigners. For a discussion of the technical issues, see U.S. Congress, Office of Technology Assessment, ReducingLaunch Operations Costs: New Technologies and Practices, OTA-TM-ISC-28 (Washington, DC: U.S. GovernmentPrinting Office, September 1988).15. NASA Manned Spacecraft Center and Marshall Space Flight Center, “Study of Integral Launch andReentry System,” RFP MSC BG721-28-9-96C and RFP MSFC 1-7-21-00020, October 30, 1968. Copy in JohnsonSpace Center historical archives.
Quoted in Hallion and Young, “Space Shuttle: Fulfillment of a Dream,” p. 995.16. NASA had created a four-phase project development scheme, which finally became codified in August1968. Phase A consisted of advanced studies (or later, preliminary analysis); Phase B, project definition; PhaseC, design; and Phase D, development and operations. See Hallion and Young, “Space Shuttle: Fulfillment of aDream,” pp. 995–96. See also Arnold S. Levine, Managing NASA in the Apollo Era (Washington, DC: NASA SP-4102,1982), pp. 158–61.****EU4 Chap 2 (161-192)4/2/0112:45 PMPage 165EXPLORING THE UNKNOWN••••165Launch and delivery of propulsive stages and payloadsOrbital delivery of propellantSatellite servicing and maintenanceShort-duration manned orbital missionsThe report considered three classes of vehicles. Class I referred to reusable orbiting vehicles launched on expendable boosters.
Class II applied to vehicles using a stage and a half.Class III meant two-stage vehicles in which both the booster and the orbiter were fully reusable.On February 13, 1969, President Richard M. Nixon requested that a high-level studybe conducted to recommend a future course of activities for the overall civilian space program.17 The Space Task Group (STG), chaired by Vice President Spiro T. Agnew, deliveredits report on September 15, 1969.18 The STG also recommended an RLV that would:•••Provide a major improvement over the present way of doing business in terms of costand operational capabilityCarry passengers, supplies, rocket fuel, other spacecraft, equipment, or additionalrocket stages to and from LEO on a routine, aircraft-like basisBe directed toward supporting a broad spectrum of both DOD and NASA missionsAs conceptualized in the STG report, a reusable space transportation system wouldhave as the following components:••A reusable chemically fueled shuttle operating between Earth’s orbit and LEO in anairline-type mode (Figures 2–1 and 2–2)A chemically fueled space tug or vehicle for moving people and equipment to differentEarth orbits and as a transfer vehicle between the lunar-orbit base and the lunar surfaceFigure 2–1.
This 1969 artist’s rendering depicts what a fullyreusable Space Shuttle would look like during takeoff. (NASAphoto)Figure 2–2. This artist’s conception, also from 1969, shows afully reusable Space Shuttle at the point of separation when theorbiter leaves the atmosphere. The larger vehicle that boostedthe orbiter was then to be piloted back to Earth. (NASA photo)17. See Logsdon, gen. ed., Exploring the Unknown, 1: 383–85.18. See Document III-25 in ibid., 1: 522–43.****EU4 Chap 2 (161-192)166•4/2/0112:45 PMPage 166DEVELOPING THE SPACE SHUTTLEA reusable nuclear stage for transporting people, spacecraft, and supplies betweenEarth orbit and lunar orbit and between LEO and geosynchronous orbit and forother deep space activities19Of these elements, only the Space Shuttle has been built to date.As noted above, many aerospace engineers within both NASA and industry favored theClass III fully reusable shuttle-type vehicles because they seemed to offer the cheapest operations costs, especially at high launch rates.
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