12 September 1966: At 14:42:26.546 UTC (9:42:26 a.m., Eastern Standard Time), Gemini XI was launched by a Titan II GLV from Launch Complex 19, Cape Canaveral Air Force Station. On board were NASA astronauts Charles (“Pete”) Conrad, Jr., Command pilot, on his second space flight; and Richard Francis Gordon, Jr., Pilot.
Earlier that morning, at 13:05:01.725 UTC (8:05:01 EST), a Gemini Agena Target Vehicle, GATV 5006, had been launched by an Atlas Agena D rocket from Launch Complex 14 and placed in a near circular orbit. Its perigee was 156.43 nautical miles (289.70 kilometers) and apogee, 165.82 nautical miles (307.10 kilometers). It completed an orbit in 1 hour, 30 minutes, 33.6 seconds.
Gemini XI made a direct first orbit rendezvous with the Agena Target Vehicle. Five maneuvers were required to match orbits, and rendezvous occurred at 11:07 a.m., and docking at 11:16 a.m. Each astronaut practiced two docking exercises. At 2:14:14 p.m., a maneuver placed the combined spacecraft into a 178.02 mile (154.70 nautical mile/286.50 kilometer) × 189.08 mile (164.31 nautical mile/304.30 kilometer) orbit with a period of 1 hour, 30 minutes, 25.2 seconds.
At 9:51 a.m.,13 September, Gordon exited the Gemini capsule to begin a Extra Vehicluar Activity (“EVA”). He recovered a micrometeorite detector and was to detach one end of a 30 meter (98.43 feet) tether from the Agena and attach it to the Gemini. The effort proved exhausting and Gordon’s space suit life support system was unable to control the heat. Perspiration fogged Gordon’s faceplate and obscured his vision. He stopped to rest. Conrad ordered him to return to the Gemini, which he did at 10:12 a.m.
On 14 September at 2:12:41 EST, the Agena engine was fired to raise the combined vehicles into a 853.8 mile (741.9 nautical mile/1,374.10 kilometer) × 180.01 mile (156.43 nautical mile/289.70 kilometer) elliptical orbit. The orbital period increased to 101.52 minutes. After two orbits, the Agena engine was fired again to lower the spacecraft back down to a 178.02 mile × 178.02 mile (154.70 nautical mile/286.50 kilometer) × 189.08 (164.31 nautical mile/304.30 kilometer) orbit.
Gordon opened his hatch to begin a “standup” EVA at 7:49 a.m., 14 September. He took photographs and conducted various experiments. This EVA period lasted 2 hours, 8 minutes.
The two spacecraft separated and Gemini XI moved to the end of the tether. Conrad began a slow rotation around the Agena, keeping the tether taut. The circular motion created “artificial gravity.” After about three hours, the tether was released. The spacecraft moved apart, and another rendezvous was performed.
Gemini XI’s retrorockets were fired at 8:24:03 a.m. EST, 15 September, and reentry began. It splashed down in the western Atlantic Ocean at N. 24.25, W. 70.00, at 8:59:35 EST, just 3.04 miles (4.9 kilometers) from the target point. Gemini XI had completed 44 orbits. Total duration of the mission was 2 days, 23 hours, 17 minutes, 9 seconds. The recovery vessel was the Iwo Jima-class amphibious assault ship USS Guam (LPH-9).
GATV 11 decayed 30 September 1966.
The two-man Gemini spacecraft was built by the McDonnell Aircraft Corporation of St. Louis, Missouri, the same company that built the earlier Mercury space capsule. The spacecraft consisted of a reentry module and an adapter section. It had an overall length of 19 feet (5.791 meters) and a diameter of 10 feet (3.048 meters) at the base of the adapter section. The reentry module was 11 feet (3.353 meters) long with a diameter of 7.5 feet (2.347 meters). The weight of the Gemini varied from ship to ship.
The Titan II GLV was a “man-rated” variant of the Martin SM-68B intercontinental ballistic missile. It was assembled at Martin’s Middle River, Maryland plant so as not to interfere with the production of the ICBM at Denver, Colorado. Twelve GLVs were ordered by the Air Force for the Gemini Program.
The Titan II GLV was a two-stage, liquid-fueled rocket. The first stage was 63 feet (19.202 meters) long with a diameter of 10 feet (3.048 meters). The second stage was 27 feet (8.230 meters) long, with the same diameter. The 1st stage was powered by an Aerojet Engineering Corporation LR-87-7 engine which combined two combustion chambers and exhaust nozzles with a single turbopump unit. The engine was fueled by a hypergolic combination of hydrazine and nitrogen tetroxide. Ignition occurred spontaneously as the two components were combined in the combustion chambers. The LR-87-7 produced 430,000 pounds of thrust. It was not throttled and could not be shut down and restarted. The 2nd stage used an Aerojet LR-91 engine which produced 100,000 pounds of thrust.
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