Canceled Apollo missions Schirra's crew would fly the C mission, first manned CSM (Block II CSM-101, retrofitted with the cabin safety improvements) as Apollo 7 in October 1968. McDivitt's crew and mission were kept as the first manned development LM flight (D mission); this was planned to be Apollo 8 in December 1968, now using a single Saturn V launch vehicle instead of two separate Saturn IB launches. The E mission was planned as an elliptical medium Earth orbit test of the operational LM with the CSM in a simulated lunar mission to an apogee of , to be commanded by Frank Borman
Canceled Apollo missions Apollo–Soyuz Test Project. Skylab 5 would have been a short 20-day mission to conduct scientific experiments and boost Skylab into a higher orbit. Brand, Lind, and William B. Lenoir (science pilot) would have been the crew. Two complete Saturn Vs went unused after the Apollo program, SA-514 and SA-515, as well as the third stage of the SA-513. SA-513 was the launch vehicle originally planned for the Apollo 18 mission, which was used to launch Skylab. The last complete, unflown Saturn IB, SA-209, kept on standby for a possible Skylab Rescue mission, is on display in the Rocket Garden of