Canceled Apollo missions planning their own circumlunar flight for December to upstage the Americans once again (see Zond program). McDivitt's crew—who had grown accustomed to working with LM-3 and preparing for its flight—was kept on the D mission which now became Apollo 9, while Borman's crew would fly the CSM lunar orbit mission on Apollo 8, and the E mission was canceled. The swap of crews was also decisive in who would be the first man to walk on the Moon. Pete Conrad was backup Commander for McDivitt's crew, and by the process of crew rotation, would have been in line for Commander
Apollo 15 operations on the Lunar surface kg) of oxygen had been lost. About half of the total amount was reserve. Scott and Irwin would state in the post-flight Technical Debrief that Mission Control should have awakened them as soon as the leak was detected. Once they were awake, it was decided to start their preparations for the first lunar EVA of their mission. As with everything in Apollo, it was an involved procedure. Not only did they have to prepare "Falcon", but had to don their space suits. "Apollo 15" was the first crew that got to sleep in long johns rather than having to stay