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
Journey of Apollo 15 to the Moon so that there was even heat distribution. Nearly 15 hours after launch, the crew switched off the lights in the cabin and went to sleep. The second day of Apollo 15 centered around the second planned midcourse correction and a preliminary check of the Lunar Module, "Falcon". Mission Control first got the crew to perform a 0.7 second burn of the SPS engine before the planned second course correction. This was designed to isolate the location of the short in the Delta-V Thrust switch. The burn allowed Mission Control to confirm that the SPS would only be ignited accidentally if