Apollo 9 to land on the Moon; when the crews for Apollo 8 and 9 were swapped, their backup crews were also swapped. Since the rule of thumb was for backup crews to fly as prime crew three missions later, this put Neil Armstrong's crew (Borman's backup) in position for the first landing mission Apollo 11 instead of Pete Conrad's crew, who made the second landing on Apollo 12. Apollo 9 was the first space test of the complete Apollo spacecraft, including the third critical piece of Apollo hardware besides the command and service module and the Saturn V launch vehicle—the lunar
Apollo 1 bearing on the accident. Manned Apollo flights were suspended for 20 months while the command module's hazards were addressed. However, the development and unmanned testing of the lunar module (LM) and Saturn V Moon rocket continued. The Saturn IB launch vehicle for Apollo 1, AS-204, was used for the first LM test flight, Apollo 5. The first successful manned Apollo mission was flown by Apollo 1's backup crew on Apollo 7 in October 1968. AS-204 was to be the first manned test flight of the Apollo command and service module (CSM) to Earth orbit, launched on a Saturn IB rocket.