List of Apollo mission types

In September 1967, Owen Maynard of the Manned Spacecraft Center in Houston, Texas proposed a series of Apollo missions that would lead up to a manned lunar landing. Seven mission types were outlined, each testing a specific set of components and tasks, and each previous step would need to be completed successfully before the next mission type could be undertaken. These were:

The planned sequence was changed when it became clear the first manned Lunar Module, LM-3, would not be ready in time for the December 1968 launch of Apollo 8, so this was flown as a lunar orbital mission using just the CSM (sometimes referred to as "a C Prime mission") and the E mission was canceled.

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