Gemini 6A

Gemini 6 (GT -6, also Gemini 6A ) was a manned space flight under the U.S. Gemini program.

The crew

Shortly after the landing of Gemini 3, on April 5, 1965, NASA announced that for the next available mission Gemini 6, the roles of the main and backup crew ( the crews of Gemini 4 and Gemini 5 Been training) exchanged would. As commander of the Mercury veteran Walter Schirra was assigned as a pilot of space newcomer Tom Stafford. The Gemini 3 astronauts Virgil Grissom and John Young were assigned to the backup crew.

Preparation

Gemini 6 was to be the first flight in the program in which the spacecraft is on the verge of a launched target satellite approach (Rendezvous ) and should couple to him ( docking ). A planned exit from the spaceship was deleted in July 1965 from the flight plan.

The Gemini spacecraft was delivered on August 4 at Cape Kennedy, the Titan rocket erected on 31 August at the launch pad. Because of a hurricane, the work was delayed, and the spacecraft was mounted on 17 September on the launcher.

The launch of Gemini 6 was scheduled for October 25. Shortly before this the start of the target satellite GATV -6 with an Atlas - Agena rocket instead, but the Agena stage did not reach orbit. Apparently, the satellite had exploded. The launch of Gemini 6 was subsequently canceled. Schirra and Stafford, who were already in their spaceship had to get out again.

The idea of ​​dual launches

Briefly, there was frustration at NASA, but then came the bold idea that instead of an Agena should serve a Gemini spacecraft as rendezvous target. The main difficulty was that within two weeks would have done two Gemini launches. But that was hardly possible, because it was only a start ramp is available, and the necessary tests lasted for several weeks.

In just three days, all the technical issues have been addressed and explained for solvable. The possibility of a double flight was so important that this project of President Lyndon B. Johnson was announced personally on October 28. The launch was announced for January 1966, but internally they worked out on a date in December.

One of the problems was that all ground stations that followed the tracks of the Gemini spacecraft can maintain connections with two spaceships at the same time had to be it for voice or for telemetry data.

The flight was renamed Gemini 6 -A, to clarify that the mission profile had changed. The launch of Gemini 7, which broke up with Frank Borman and Jim Lovell to a long-duration flight, should be done first so that the numbering was no longer in chronological order.

When connecting speakers ( Capcom ) for Gemini 6 were the same four astronauts who were in contact already with Gemini 7: Alan Bean, Elliott See, Charles Bassett and Eugene Cernan.

Double start and take-off

Immediately after the successful launch of Gemini 7 on December 4, began preparations for the launch of Gemini 6 -A. The assembly work and tests ran so smoothly that the initially planned for 13 December start on December 12 has been brought forward.

The preparations were normal, but shortly before lift-off events moved swiftly: The engines had already ignited when a poorly secured cable broke away from the rocket. This cable should only fall off when you lift and start a clock in the cockpit. As the clock was running, the rocket is not moving but the engine automatically switched off again. Schirra saw the running clock that signaled the take off, and noticed the engine shutdown. The signaled highest risk, because obviously was just the start was unsuccessful. Actually Schirra would now have to trigger the ejection seats for himself and Stafford as a commander, because a vollbetankte rocket that falls back on the launch pad shortly after the start, just may explode. But Stafford did not trust the clock, because he had felt no upward movement. He stayed quiet and just announced the shutdown engines. Once it became clear that the missile would not explode, and that the ejection seats were secured, Schirra and Stafford were taken out of the Gemini spacecraft. The start was delayed for several days.

In the investigation it was found that not only some cable lawless sat, but also that a dust cover was forgotten in one of the engines, which would have resulted regardless of the sloping cable to a rejected take-offs.

History of the flight

The third launch attempt on December 15 was then carried out without problems. In the fourth orbit Gemini 6 -A hit on Gemini 7, which was eleven days in orbit. Schirra and Stafford approached Gemini 7 to 40 meters, when the two ships were standing still relative to each other.

The Soviet Vostok spacecraft had indeed already in 1962 and 1963 approached each other, but based this on precise orbit calculations at startup, and not on the control of the spacecraft itself Thus the maneuver of Gemini 6 -A and Gemini 7 was the first controlled rendezvous of space.

Gemini 6 still had enough fuel to fly different maneuvers and approach Gemini 7 to 30 cm. On one occasion, Schirra and Stafford inspected the rear of Gemini 7, in another they flew nose to nose. Gemini 7 was already a long time in space and had not so large fuel reserves, so that Borman and Lovell as to control themselves more actively served as a passive target.

During the rendezvous Lovell asked from the Gemini 7: "How 's the view? ". Schirra replied: " Pretty bad. I can see through the window and see you guys in there. "

Since all mission objectives were met, the landing of Gemini 6A was launched flight after only one day. For the first time the splashdown was broadcast live on television. Schirra and Stafford could be heave together with the landing capsule aboard the USS Wasp.

Importance for the Gemini Project

Gemini 6 -A and Gemini 7 showed impressively how exactly the Gemini spacecraft could control. Changes in velocity of only 3 cm / s allowed very fine changes in the trajectories. The next flight, Gemini 8, should then, as already planned for Gemini 6, couple to an Agena target satellite, a further step on the way to the moon flight.