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The Saturn Vehicle Evaluation Committee, better known as the Silverstein Committee, was a US government commission assembled in 1959 to recommend specific directions that NASA could take with the Saturn rocket program. The committee was chaired by Abe Silverstein, a long-time NASA engineer, with the express intent of selecting upper stages for the Saturn after a disagreement broke out between the Air Force and Army over its development. During the meetings the Committee members outlined a number of different potential designs, including the low-risk solution von Braun was developing with existing ICBM airframes, as well as versions using entirely new upper stages developed to take full advantage of the booster stage. The advantages of using new uppers were so great that the committee won over an initially skeptical von Braun, and the future of the Saturn program changed forever. ==Background== In 1957 the Department of Defense (DoD) released a set of requirements for a new heavy-lift booster for missions starting in the early 1960s. At the time, all three branches of the US military were in the process of developing their own rockets, which led to considerable in-fighting between them on the priority of future developments. In 1956 the US Air Force won the concession that long range rocketry was its domain, including all ground-to-ground missiles over range. The agreement did not cover "other roles" however, and existing projects at the Navy and Army continued as before. The Air Force was in the midst of their Dyna-Soar project, and were designing a new booster to launch it under their "SLV-4" requirement. Their primary answer to this requirement was a Titan II missile equipped with a new hydrogen-burning upper stage, the Titan C. The resulting design had a somewhat bulbous appearance; as the hydrogen fuel required large tanks, the upper stage was in diameter, compared to the of the Titan II. Other teams within the Air Force were also developing the Space Launch System concept, which combined the same Titan II with a number of solid fuel rockets as a "zeroth stage". By combining different numbers and sizes of these rockets, the launch stack could be tuned to different payloads. The SLS team also outlined a development path for a manned lunar mission under their Lunex Project proposal, using the Titan with four solids to test the re-entry vehicle from Earth orbit, and entirely new solids and liquid stages for flights to the moon. To meet the same DoD requirement for a heavy space launcher, the Army team at the Army Ballistic Missile Agency (ABMA) under the direction of a team led by Wernher von Braun studied a number of designs that clustered existing missile airframes and optionally added new engines. The design series included the "Super-Titan", "Super-Atlas" and "Super-Jupiter". The later quickly became their focus, as it consisted of technology developed at ABMA, while the Atlas and Titan were Air Force designs suffering from extended development problems. The Super-Jupiter design was based almost entirely on existing equipment, using a cluster of Redstone and Jupiter missiles to form a lower stage powered by a new engine, with an upper stage adapted from the Titan. Their proposal was much simpler and lower-risk than the Air Force proposal, which required the development of a new hydrogen-burning upper stage. Like the Air Force team, ABMA also outlined their vision of a manned lunar mission as Project Horizon, using fifteen of these rockets to build a large vehicle in Earth orbit. The newly formed Advanced Research Projects Agency (ARPA), which was put in charge of development of the launcher, sided with the ABMA design. Their only concern was that the new engines might be a risk, suggesting that more moderate upgrades of existing engines be used instead. ABMA quickly adapted the design to use eight engines developed from the Jupiter's S-3D as the H-1, as opposed to four of the proposed E-1 of the original design. ARPA was satisfied, and started funding development of both the booster at ABMA and the new H-1 engines at Rocketdyne. Contracts were tendered in October 1958 and work proceeded quickly; the first test-firing of the H-1 occurred in December and a mock-up of the booster had already been completed. Originally known as Super-Jupiter, the design became the Juno V during development, and on February 3 an ARPA memorandum officially renamed the project Saturn. Soon after, the newly formed NASA also expressed their interest in the Saturn design as part of their long-term strategy. Launches in the early 1960s would focus on low-Earth orbit using existing ICBM's as launchers, technology development for the lunar program would be based on Saturn, and the actual direct ascent lunar mission would use the massive Nova rocket, then under design at NASA. Shortly thereafter, on 9 June 1959, Herbert York, Director of Department of Defense Research and Engineering, announced that he had decided to terminate the Saturn program. York felt that the DoD should not be funding a booster whose only concrete role was to support a civilian space program. A meeting was arrange to "save" the program, which resulted in the Saturn program, and all of ABMA with it, being transferred to NASA. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Silverstein Committee」の詳細全文を読む スポンサード リンク
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