Soyuz 11

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Soyuz 11
Mission insignia
Mission statistics
Mission name Soyuz 11
Crew size 3
Call sign Янтарь (Yantar - "Amber")
Launch date June 6, 1971
07:55:09 UTC
Gagarin's Start
Landing June 30, 1971
02:16:52 UTC
Mission duration 23d/18:21:43
Number of orbits 383[1]
Related missions
Previous mission Next mission
Soyuz 10 Soyuz 12

Soyuz 11 was the first successful visit to the world's first space station, Salyut 1. However the mission ended in disaster when the crew capsule depressurised during preparations for re-entry, killing the three-man crew.[2] This accident resulted in the first and to date only astronaut deaths to occur in space (not in high atmosphere). The cosmonauts aboard Soyuz 11 were Vladislav Volkov, Georgi Dobrovolski and Viktor Patsayev.[3][4][5]

Contents

[edit] Crew

Number in parentheses indicates number of spaceflights by each individual prior to and 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 according to the mission rules, the prime crew was replaced with the back-up crew. 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] Reserve crew

[edit] Mission parameters

  • Mass: 14,970 pounds (6,790 kg)
  • Perigee: 163 kilometres (101 mi)
  • Apogee: 237 km (147 mi)
  • Inclination: 51.5°
  • Period: 88.4 min

[edit] Mission highlights

The Soyuz spacecraft was launched on June 6, 1971, from Baikonur Cosmodrome in central Kazakh SSR. Several months earlier, the first mission to the Salyut, Soyuz 10, had failed to successfully dock with the station.[6] Soyuz 11, however, successfully docked with Salyut 1 on June 7 and the cosmonauts remained on-board for 22 days, setting space endurance records that would hold until the American Skylab 2 mission in May-June 1973.[2]

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 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 the launch 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. Pravda released news of the mission and regular updates while it was in progress.

[edit] Death of crew

On June 30, 1971, after an apparently normal re-entry of the capsule of the Soyuz 11 mission, the recovery team opened the capsule to find the crew dead.[1][2][7] It quickly became apparent that they had suffocated. The fault was traced to a breathing ventilation valve, located between the orbital module and the descent module, that had been jolted open as the descent module separated from the service module.[8][9] The two were held together by explosive bolts designed to fire sequentially, but in fact, they fired simultaneously while over France.[8] The force of this caused the internal mechanism of the pressure equalization valve to loosen a seal that was usually discarded later, and normally allowed automatic adjustment of the cabin pressure.[1][8] When the valve opened at 168 kilometers (104 mi), the gradual loss of pressure was fatal within seconds.[8][10] By 935 seconds after the retrofire, the cabin pressure was zero, and remained there until the ship hit the earth's atmosphere.[8]

Located beneath the cosmonaut's couches, the valve was impossible to locate and block the leak before the air was lost. It is estimated that the cabin lost all its atmosphere in about 30 seconds. Flight recorder data from the single cosmonaut outfitted with biomedical sensors showed death occurred within 40 seconds of pressure loss.

Film later declassified showed support crews attempting CPR on the cosmonauts.[11] They attempted to save the cosmonauts in the hope that the decompression accident occurred in a time-frame that might have allowed for some of them to be saved. Current understanding of exposure to vacuum, however, shows this to be impossible, as vacuum exposure leads to rapid deoxygenation of the blood, pulmonary hemorrhaging, and brain death within two minutes of continuous exposure.[8]

The cosmonauts were given a large state funeral and buried in the Kremlin Wall Necropolis at Red Square, Moscow near the remains of Yuri Gagarin.[2] U.S. astronaut Tom Stafford was one of the pallbearers. They were also each posthumously awarded the Hero of the Soviet Union medal. 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.[12] A Soyuz capsule would not hold three cosmonauts again until the Soyuz-T redesign in 1980, which freed enough space for three cosmonauts in lightweight pressure suits to travel in the capsule.

[edit] References

  1. ^ a b c National Aeronautics and Space Administration (NASA) (2005). Soyuz 11 (English). NASA -National Space Science Data Center. Retrieved on October 20, 2007.
  2. ^ a b c d Time Magazine (1971). Triumph and Tragedy of Soyuz 11 (English). Time Magazine. Retrieved on October 20, 2007.
  3. ^ Encyclopedia Astronautica (2007). Soyuz 11 (English). Encyclopedia Astronautica. Retrieved on October 20, 2007.
  4. ^ Mamta Trivedi (2001). 30 Years Ago: The World's First Space Station, Salyut 1 (English). Space.com - Imaginova Corp.. Retrieved on October 20, 2007.
  5. ^ CNN (1997). After glory era, cash woes hobble Russian space program (English). CNN. Retrieved on October 20, 2007.
  6. ^ Time Magazine (1971). A Troubled Salyut (English). Time Magazine. Retrieved on October 20, 2007.
  7. ^ USA Today (2003). Deadly accidents in the history of space exploration (English). USA Today. Retrieved on October 20, 2007.
  8. ^ a b c d e f NASA (1974). The Partnership: A History of the Apollo-Soyuz Test Project (English). NASA. Retrieved on October 20, 2007.
  9. ^ NASA. The crew of Soyuz 11 (English). NASA. Retrieved on October 20, 2007.
  10. ^ Jane's Information Group (2003). A brief history of space accidents (English). Jane's Information Group. Retrieved on October 20, 2007.
  11. ^ This footage was shown during the 1994 TV adaptation of the documentary Moon Shot by Alan Shepard and Deke Slayton.
  12. ^ Charles R. Smith (2003). Space Race Is Alive and Well (English). NewsMax. Retrieved on October 20, 2007.

[edit] Further reading

  • United States Congress: Office of Technology Assessment (March 30, 2005). Salyut: Soviet Steps Toward Permanent Human Presence in Space - A Technical Memorandum. Seattle: University Press of the Pacific, 80 pages. ISBN 1-4102-2138-5. 
  • Ivanovich, Grujica S. (February 2008). Salyut - The First Space Station: Triumph and Tragedy. Praxis, 300 pages. ISBN 0387735852. 

[edit] External links

Coordinates: 45°55′N, 63°20′E