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Apollo 4, (also known as AS-501), was the first, unmanned test flight of the Saturn V launch vehicle, which was used by the U.S. Apollo program to send the first astronauts to the Moon. The space vehicle was assembled in the Vertical Assembly Building, and was the first to be launched from Launch Complex 39 at the John F. Kennedy Space Center on Merritt Island, Florida, facilities built specially for the Saturn V. Apollo 4 was an "all-up" test, meaning all rocket stages and spacecraft were fully functional on the initial flight, a first for NASA. It was the first time the S-IC first stage and S-II second stage flew. It also demonstrated the S-IVB third stage's first in-flight restart. The mission used a Block I Command Service Module (CSM) modified to test several key Block II revisions, including its heat shield at simulated lunar-return velocity and angle. Originally planned for late 1966, the flight was delayed to November 9, 1967, largely due to development problems of the S-II stage encountered by North American Aviation, the manufacturer of the stage. Delay was also caused, to a lesser extent, by a large number of wiring defects found by NASA in the Apollo spacecraft, also built by North American. The mission was the first Apollo flight after the stand-down imposed after the Apollo 1 fire which killed the first Apollo crew. It was the first to use NASA's official Apollo numbering scheme established in April 1967, designated Apollo 4 because there had been three previous unmanned Apollo/Saturn flights in 1966, using the Saturn IB launch vehicle. The mission lasted almost nine hours, splashing down in the Pacific Ocean, achieving all mission goals. NASA deemed the mission a complete success, because it proved the Saturn V worked, an important step towards achieving the Apollo program's objective of landing astronauts on the Moon and bringing them back safely, before the end of the decade. ==Objectives== AS-501 was the Saturn V's first flight. At the time, it was the largest launch vehicle to ever attempt a flight.〔Reynolds 2002, pp. 81–82〕 This mission was NASA's first to use "all-up" testing, a decision that goes back to late-1963.〔 George Mueller, the head of the NASA Office of Manned Space Flight at that time, was a systems engineer who previously worked on military missile projects, recognized all-up testing was successfully used to rapidly develop the Air Force's Minuteman ICBM program, and thought it could be used to meet Apollo's schedule.〔Murray & Cox 1989, pp. 156–162〕 Previously, the way Wernher von Braun's team at the Marshall Space Flight Center, and the old NACA Langley Research Center engineers tested new rockets was by testing each stage incrementally.〔 The Saturn V's test program departed from the conservative incremental approach previously used by the Marshall and Langley engineers.〔 It would be tested all at once, with all stages live and fully flight-worthy, including an Apollo Command/Service Module (CSM).〔Cadbury 2006, p. 274〕 This decision dramatically streamlined the program's test flight phase, eliminating four missions, but it required everything to work properly the first time.〔 Apollo program managers had misgivings about all-up testing but agreed to it with some reluctance since incremental component tests would inevitably push the lunar landing mission past the 1970 goal.〔Neufeld 2007, pp. 388–389, 400〕 The mission was the first launch from the Kennedy Space Center Launch Complex 39, specifically built for the Saturn V.〔Reynolds 2002, pp. 84–85〕 Since this was an all-up test, it was the S-IC first stage and S-II second stage's first launch. It would also be the first time that the S-IVB third stage would be restarted in Earth orbit, and the first time that the Apollo spacecraft would reenter the Earth's atmosphere at the speed of a lunar return trajectory. The payload was a CSM, serial number 017.〔Brooks 1979, ("''Apollo 4'' and Saturn V" ), CH9-5〕 This was a Block I design meant for systems testing, not the Block II spacecraft designed for use with the Lunar Module (LM) on the actual Moon landings.〔 However, several significant Block II modifications were made for certification, since no all-up Block II spacecraft would fly without a crew.〔 The modifications included: a new CM heat shield outer covering; a new CM-to-SM umbilical connector; moving the VHF scimitar antennas from the CM to the SM; a new Unified S-band antenna; and a modified crew compartment hatch.〔 A dummy LM known as a Lunar Module Test Article, LTA-10R was carried as ballast to simulate the loadings of the LM on the launch vehicle. At , the LTA-10R was slightly lighter than a nominal LM used on the first lunar landing, which weighed . 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「Apollo 4」の詳細全文を読む スポンサード リンク
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