Apollo 9 was a mission in NASA's Apollo program. It was the third crewed mission in the Apollo program and was the first flight of the Command/Service Module (CSM) with the Lunar Module (LM). The crew was Commander James A. McDivitt, Command Module Pilot David R. Scott, and Lunar Module Pilot Russell L. Schweickart. The mission was launched on March 3, 1969. The mission tested several things which were important for landing on the Moon, including the LM engines, backpack life support systems, navigation systems, and docking maneuvers.