Cancelled Space Shuttle missions

During the Space Shuttle program, several missions were canceled. Many were canceled as a result of the Challenger and the Columbia disasters. Many early missions were canceled due to delays in the development of the shuttle. Others were canceled because of changes in payload and missions requirements.

In 1972, NASA's planners had projected for 570 shuttle missions between 1980 and 1991. Later, this estimate was lowered to 487 launches between 1980 and 1992. The details of the first 23 projected missions, listed in the third edition of Manned Spaceflight (Reginald Turnill, 1978) and the first edition of the STS Flight Assignment Baseline, an internal NASA document published in October 1977, are presented below.

Originally scheduled as the first orbital test (OFT-1) for launch in June 1979. The crew was to consist of a commander and pilot, and the test flight was to last 2 days and 5 hours. No crew was named at the initial announcement of the mission, but John Young and Robert Crippen were officially announced as the STS-1 crew in March 1978, when the shuttle was still originally scheduled for a 1979 launch.

Originally scheduled as the second orbital flight test (OFT-2) for launch in July 1979. The 5-day mission was to see the crew of Fred Haise and Jack Lousma take the Teleoperator Retrieval System to the Skylab space station in order to boost it into a higher orbit.Vance D. Brand and C. Gordon Fullerton were their backups. By April 1979, when it was understood that the Shuttle could not be launched in time to rendezvous with Skylab, STS-2 was rescheduled for a 6 March 1980 launch, carrying the OSTA-1 payload and the RMS for the first time. This re-manifested STS-2 finally launched on 12 November 1981, with Joe Engle and Richard Truly in place of Haise and Lousma, respectively.

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