Cancelled Space Shuttle missions

Space Shuttle missions designated STS-3xx (officially called Launch On Need (LON) missions) were rescue missions which would have been mounted to rescue the crew of a Space Shuttle if their vehicle was damaged and deemed unable to make a successful reentry. Such a mission would have been flown if Mission Control determined that the heat shielding tiles and reinforced carbon-carbon panels of a currently flying orbiter were damaged beyond the repair capabilities of the available on-orbit repair methods. These missions were also referred to as Launch on Demand (LOD) and Contingency Shuttle Crew S

cancelled space probe

thumb|Comparison of International Space Station and [[Hubble Space Telescope orbits]] STS-400 was the Space Shuttle contingency support (Launch On Need) flight that would have been launched using if a major problem occurred on during STS-125, the final Hubble Space Telescope servicing mission (HST SM-4).

STS-62-A was a planned NASA Space Shuttle mission to deliver a reconnaissance payload (Teal Ruby) into polar orbit. It was expected to use Discovery. It would have been the first crewed launch from Vandenberg Air Force Base in California, and the first crewed mission to go into polar orbit.

STS-61-M was a proposed NASA Space Shuttle program mission, planned for July 1986 but canceled following the Space Shuttle Challenger disaster (STS-51-L).

STS-61-H was a NASA Space Shuttle mission planned to launch on 24 June 1986 using Columbia. However, it was canceled after the Challenger disaster.

STS-61-F was a NASA Space Shuttle mission planned to launch on 15 May 1986 using Challenger. It was canceled after Challenger was destroyed earlier that year.

STS-61-G was a NASA Space Shuttle mission planned to launch on 20 May 1986, using Atlantis. The main objective of this mission was to launch the Galileo spacecraft toward Jupiter using the Centaur-G upper stage. It was canceled after the Space Shuttle Challenger disaster.

STS-61-E was a NASA Space Shuttle mission planned to launch on 6 March 1986 using Columbia. It was canceled after the Challenger disaster.