Canceled Apollo missions

Several planned missions of the Apollo manned Moon landing program of the 1960s and 1970s were canceled for a variety of reasons, including changes in technical direction, the Apollo 1 fire, hardware delays, and budget limitations. Immediately after the program achieved its primary objective in July 1969 with Apollo 11 to land men on the Moon and return them safely, nine more landing missions were planned, but the last three, Apollo 18, 19 and 20, were canceled.

In September 1962, NASA planned to make four manned low Earth orbital test flights of partially equipped Block I Command/Service Modules (CSM) using the Saturn I launch vehicle, designated SA-11 through SA-14, in 1965 and 1966. However, the limited payload capability of the Saturn I compared to the uprated Saturn IB would have severely limited the systems carried, and thus the testing value of these flights. Therefore, NASA canceled these flights in October 1963, and replaced them with two manned Saturn IB missions, designated AS-204 and AS-205. These would be followed by the first unmanned flight of the Lunar Module (LM) on AS-206, then the third manned mission, designated AS-207/208, would use AS-207 to launch the crew in an improved Block II CSM, which would rendezvous and dock with the LM launched unmanned on AS-208.

The crew selected on March 21, 1966 for AS-204 consisted of Command Pilot Virgil "Gus" Grissom, Senior Pilot Edward H. White, and Pilot Roger Chaffee, who named their mission Apollo 1. The AS-205 crew were Wally Schirra, Donn Eisele and Walter Cunningham. However the second flight was later deemed unnecessary and officially canceled on December 22, 1966.

Schirra's crew then became the backup for Grissom's crew, and the manned LM mission became the second manned mission, redesignated AS-205/208 and crewed by Grissom's original backup crew: Command Pilot Jim McDivitt, CSM Pilot David Scott and LM Pilot Rusty Schweickart. They immediately began their training in the first Block II Command Module CM-101, as Grissom's crew were preparing for a February 1967 launch.

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