Salyut 7 (Russian: Салют-7; English: Salute 7) was the final space station launched into Low Earth orbit as part of the Soviet Union's Salyut Program. Launched on April 19, 1982, on a Proton rocket from Site 200/40 at the Baikonur Cosmodrome in the USSR, Salyut 7 was part of the transition from "monolithic" to "modular" space stations, acting as a testbed for docking of additional modules and expanded station operations. It was also the tenth space station of any kind launched.
Salyut 7 photographed following the undocking of Soyuz T-13, September 25, 1985
Salyut 7 was the back-up vehicle for Salyut 6 and very similar in equipment and capabilities. With delays to the Mir programme it was decided to launch the back-up vehicle as Salyut 7. In orbit the station suffered a number of technical failures though it benefited from the improved payload capacity of the visiting Progress and Soyuz craft and the experience of its crews who improvised many solutions (such as a fuel line rupture in September 1983 requiring EVAs by the Soyuz T-10 to repair).
It was aloft for eight years and two months (a record not broken until Mir), during which time it was visited by 10 crews constituting 6 main expeditions and 4 secondary flights (including French and Indian cosmonauts). The mission saw two flights of Svetlana Savitskaya making her the second woman in space since 1963 and the first to perform an EVA. Aside from the many experiments and observations made on Salyut 7, the station also tested the docking and use of large modules with an orbiting space station. The modules were called "Heavy Cosmos modules" though in reality were variants of the TKS spacecraft intended for the cancelled Almaz military space station. They helped engineers develop technology necessary to build Mir.
It had two docking ports, one on either end of the station, to allow docking with the Progress unmanned resupply craft, and a wider front docking port to allow safer docking with a Heavy Cosmos module. It carried three solar panels, two in lateral and one in dorsal longitudinal positions, but they now had the ability to mount secondary panels on their sides. Internally, the Salyut 7 carried electric stoves, a refrigerator, constant hot water and redesigned seats at the command console (more like bicycle seats). Two portholes were designed to allow ultraviolet light in, to help kill infections. Further, the medical, biological and exercise sections were improved, to allow long stays in the station. The BST-1M telescope used in Salyut 6 was replaced by an X-ray detection system.
Following up the use of Cosmos 1267 on Salyut 6, the Soviets launched Cosmos 1443 on March 2, 1983, from a Proton SL-13. It docked with the station on March 10, and was used by the crew of Soyuz T-9. It jettisoned its recovery module on August 23, and re-entered the atmosphere on September 19. Cosmos 1686 was launched on September 27, 1985, docking with the station on October 2. It did not carry a recovery vehicle, and remained connected to the station for use by the crew of Soyuz T-14. Ten Soyuz T crews operated in Salyut 7. Only two InterCosmos "guest cosmonauts" worked in Salyut 7. The first attempt to launch Soyuz T-10 was aborted on the launch pad when a fire broke out at the base of the vehicle. The payload was ejected, and the crew was recovered safely.
CREWS AND MISSIONS
Salyut 7 had six resident crews:
The first crew, Anatoli Berezovoy and Valentin Lebedev, arrived on May 13 1982 on Soyuz T-5 and remained for 211 days until December 10 1982.
On June 27, 1983 the crew of Vladimir Lyakhov and Alexander Alexandrov arrived on Soyuz T-9 and remained for 150 days, until November 23, 1983.
On February 8 1984 Leonid Kizim, Vladimir Solovyev, and Oleg Atkov began a 237 day stay, the longest on Salyut 7, which ended on October 2, 1984.
Vladimir Dzhanibekov and Viktor Savinykh (Soyuz T-13) arrived at the space station on June 6, 1985.
On September 17, 1985 Soyuz T-14 docked with the station carrying Vladimir Vasyutin, Alexander Volkov, and Georgi Grechko. Eight days later Dzhanibekov and Grechko left the station and returned to Earth after 103 days, while Savinyikh, Vasyutin, and Volkov remained on Salyut 7 and returned to Earth on November 21, 1985 after 65 days.
On May 6, 1986 Soyuz T-15 carrying Leonid Kizim and Vladimir Solovyov docked with the space station. The Soyuz had come from the Mir space station and returned to Mir after 50 days on Salyut.
There were also four visiting missions, crews which came to bring supplies and make shorter duration visits with the resident crews.
The station suffered from two major problems, the first of which required extensive repair work to be performed on a number of EVAs. On 9 September 1983, during the stay of Vladimir Lyakhov and Alexander Alexandrov, while reorienting the station to perform a radiowave transmission experiment, Lyakhov noticed the pressure of one fuel tank was almost zero. Following this, Alexandrov spotted a fuel leak looking through the aft porthole. Ground control decided to try to repair the damaged pipes, in what was to be the most complex repair attempted during EVA at the time. However this was to be attempted by the next crew, the current one lacking the necessary training and tools. The damage was eventually repaired by Leonid Kizim and Vladimir Solovyov, who after four EVA managed to fix two leaks but needed a special tool to fix the third. The tool was delivered by Soyuz T-12, and the leak was subsequently fixed.
On 12 February 1985, contact with Salyut 7 was lost. The station began to drift, and all systems shut down. At this time the station was uninhabited, after the departure of Leonid Kizim, Vladimir Solovyov and Oleg Atkov, and before the next crew arrived. Once again ground control decided to attempt repairing the station, which was performed by Vladimir Dzhanibekov and Viktor Savinykh. After manually docking with the station (the automatic system didn't have power) they found the hull intact, although the lack of power caused the station's walls to be covered in ice, and made working very difficult. The fault was eventually found to be electrical sensor that determined when the batteries need charging. Once the batteries were replaced, the station started charging them, and warmed up over the next few days.
Salyut 7 deorbited on February 7, 1991.