Apollo (spacecraft) Surface Experiment Packages ALSEP, the modularized equipment transporter (MET) (a hand-pulled equipment cart used on Apollo 14), the Lunar Rover (Apollo 15, 16 and 17), a surface television camera, surface tools, and lunar sample collection boxes. The ascent stage contained the crew cabin, instrument panels, overhead hatch/docking port, forward hatch, optical and electronic guidance systems, reaction control system, radar and communications antennas, ascent rocket engine and propellant to return to lunar orbit and rendezvous with the Apollo Command and Service Modules. The spacecraft–LM adapter (SLA), built by North American Aviation (Rockwell), was a conical aluminum structure which supported the service
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