Gemini 5 Lapel Pin
Gemini 5, carrying astronauts Gordon Cooper and Charles "Pete" Conrad was the third crewed Earth-orbiting spacecraft of the Gemini series. The flight was designed to last eight days and test rendezvous procedures. The major objectives of this mission were to demonstrate a long-duration crewed flight, evaluate the effects of long periods of weightlessness on the crew, and test rendezvous capabilities and maneuvers using a rendezvous evaluation pod. Secondary objectives included demonstration of all phases of guidance and control systems to support rendezvous and controlled reentry guidance, to evaluate the fuel cell power system and rendezvous radar, to test the capability of either pilot to maneuver the spacecraft in orbit to close proximity with another object, and to conduct 17 experiments.
Gemini 5 was launched from Complex 19 on 21 August 1965 at 8:59:59 a.m. EST (13:59:59.518 UT) and inserted into a 162.0 x 350.1 km Earth orbit at 9:05:55. The rendezvous evaluation pod (REP), a 34.5 kg optical and electronic duplicate of the Agena planned for use in later Gemini rendezvous missions was deployed two hours into the flight on the second revolution. About 36 minutes into the evaluation of the rendezvous system, the crew noticed the pressure in the oxygen supply tank of the fuel cell system was dropping. At some point earlier in the flight the oxygen supply heater element had failed, and the pressure dropped from nominal pressure of 850 psia to a low of 65 psia 4 hours and 22 minutes into the flight. This was still above the 22.2 psia minimum but it was decided to cancel the REP exercise and power the spacecraft down. An analysis was carried out on the ground and a powering up procedure was started on the seventh revolution. Over the rest of the mission the pressure slowly rose in the fuel cells and sufficient power was available at all times.