Apollo 9 in early 1969. However, LM problems again prevented it from being ready for the D mission by December, so NASA officials created another mission for Apollo 8 using the Saturn V to launch only the CSM on the first crewed flight to orbit the Moon, and the E mission was cancelled as unnecessary. Slayton asked McDivitt and Borman which mission they preferred to fly; McDivitt wanted to fly the LM, while Borman volunteered for the pioneering lunar flight. Therefore, Slayton swapped the crews, and McDivitt's crew flew Apollo 9. The crew swap also affected who would be the first crew
Canceled Apollo missions 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 Ed White, and Pilot Roger Chaffee, who named their mission Apollo 1. AS-205 was to be named Apollo 2, and