Soyuz 11

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Soyuz 11 was the second attempted and the first successful visit to the world's first space station, Salyut 1. (Soyuz 10 was unable to dock.) The Soyuz spacecraft was launched on June 6, 1971, from Baikonur Cosmodrome in central Kazakh SSR with cosmonauts Vladislav Volkov, Georgi Dobrovolski and Viktor Patsayev aboard.

They successfully docked with Salyut 1 on June 7 and remained on-board for 22 days, setting space endurance records that would hold until the American Skylab 2 mission in May-June 1973. Upon first entering the station the crew encountered a smokey and burnt atmosphere and after replacing part of the ventilation system spent the next day back in their Soyuz until the air cleared. Their stay in Salyut was productive including live television broadcasts. However a fire broke out on day 11 of their stay nearly causing mission planners to consider abandoning the station. The planned highlight of the mission was to have been the observation of an N-1 booster launch but this was postponed. The crew also found that using the exercise treadmill as they were required to do twice a day caused the whole station to vibrate. In what was a rare move at the time, Pravda released news of the mission and regular updates while it was in progress.

On June 30, 1971, after a normal re-entry of the capsule of the Soyuz 11 mission, the recovery team opened the capsule to find the crew dead. It quickly became apparent that they had asphyxiated. The fault was traced to a valve that had been jolted open as the descent module separated from the service module. The two were held together by explosive bolts designed to fire sequentially, but in fact they fired simultaneously while over France. The valve, less than 1 mm in diameter, was supposed to equalise pressure inside the capsule in the final moments before landing, but in this case had instead allowed the cosmonauts' air to leak away into space. Located beneath the cosmonaut's couches, it proved impossible to locate and block the leak before the air was lost.

Film later declassified showed support crews attempting CPR on the cosmonauts. They attempted to save the cosmonauts in the hope that the decompression accident occurred in a timeframe that might have allowed for some of them to be saved. It is believed now that they had not been breathing for at least 15 minutes, and they were already dead when the spacecraft touched down.

The cosmonauts were given a large state funeral, and all three are buried in the Kremlin Wall Necropolis at Red Square, Moscow. U.S. astronaut Tom Stafford was one of the pallbearers. Craters on the Moon were named after the three cosmonauts.

The Soyuz spacecraft was extensively redesigned after this incident to carry only two cosmonauts. The extra room meant that the crew could wear space suits during launch and landing. A Soyuz capsule would not hold three cosmonauts again until the Soyuz-TM redesign in 1986, which freed enough space for three cosmonauts in space suits to travel in the capsule.

[edit] Crew

• Georgi Dobrovolski (1)
• Viktor Patsayev (1)
• Vladislav Volkov (2)

(1) number of spaceflights each crew member has completed, including this mission.

The prime crew for Soyuz 11 consisted of Alexei Leonov, Valeri Kubasov and Pyotr Kolodin. A medical X-ray examination four days before launch suggested that Kubasov might have tuberculosis, and per mission rules the crew were replaced with their back-up. For Dobrovolski and Patsayev this was to be their first space mission. After the failure of Salyut 2 to orbit, Kubasov and Leonov were reassigned to Soyuz 19 for the Apollo-Soyuz Test Project in 1975.

[edit] Mission parameters

• Mass: 6790 kg
• Perigee: 163 km
• Apogee: 237 km
• Inclination: 51.5°
• Period: 88.4 min