Gemini 9A (officially Gemini IX-A) was a 1966 manned spaceflight in NASA's Gemini program. It was the 7th manned Gemini flight, the 13th manned American flight and the 23rd spaceflight of all time (includes X-15 flights over ). The original crew for Gemini 9, command pilot Elliot See and pilot Charles Bassett, were killed in a crash on February 28, 1966 while flying a T-38 jet trainer to the McDonnell Aircraft plant in St. Louis, Missouri to inspect their spacecraft. The mission was flown June 3–6, 1966 by backup command pilot Thomas P. Stafford and pilot Eugene Cernan. The astronauts rendezvoused with the Augmented Target Docking Adaptor, but were unable to dock with it because the nose fairing failed to eject from the docking target due to a launch preparation error. Cernan performed a two-hour extravehicular activity, during which he was planned to demonstrate free flight in a self-contained rocket pack, the Astronaut Maneuvering Unit. He was unable to accomplish this due to stress, fatigue, and overheating.