Gemini IV (Spacecraft)

Gemini IV, which was launched on June 3, 1965, was the second manned mission of the Gemini space program, as well as the National Aeronautics and Space Administration's (NASA) first extra-vehicular activity (EVA) operation. James A. McDivitt served as commander of the mission and Edward H. White II served as pilot. The primary objectives of the Gemini IV mission included evaluating the effects of prolonged space flight on spacecraft and systems and evaluating procedures for crew rest and work cycles, eating schedules, and real time flight planning. The secondary objectives of the mission included demonstrating and evaluating EVA and controlling it by use of a hand-held maneuvering unit (HHMU) and tether; stationkeeping and rendezvous with the second stage of the Gemini launch vehicle (GLV); evaluating spacecraft systems; making in- and out-of-plane maneuvers; testing further the retro backup capability of the orbit attitude and maneuvering system (OAMS); and performing 11 experiments. All but one of the primary objectives of the Gemini IV mission were achieved. The objective involving computer controlled re-entry in the demonstration and evaluation of spacecraft systems was not flown because of inadvertent alteration of computer memory. All of the secondary objectives were met except one: stationkeeping and rendezvous was only partially successful, since separation and rendezvous was not attempted (due to fuel consumption). Gemini IV landed on June 7, 1965, 81.4 km from its attempted landing zone.