Soyuz 7K-OKS (also known as Soyuz 7KT-OK) is a version of the

Soyuz spacecraft Soyuz () is a series of spacecraft which has been in service since the 1960s, having made more than 140 flights. It was designed for the Soviet space program by the Korolev Design Bureau (now Energia). The Soyuz succeeded the Voskhod spacecraf ...

and was the first spacecraft designed for

space station A space station is a spacecraft capable of supporting a human crew in orbit for an extended period of time, and is therefore a type of space habitat. It lacks major propulsion or landing systems. An orbital station or an orbital space station i ...

flights. Its only crewed flights were conducted in 1971, with

Soyuz 10 Soyuz 10 (russian: 'Союз 10', ''Union 10'') was launched on 22 April 1971 as the world's first mission to the world's first space station, the Soviet Salyut 1. The docking was not successful and the crew, Vladimir Shatalov, Aleksei Yel ...

and

Soyuz 11 Soyuz 11 (russian: link=no, Союз 11, lit=Union 11) was the only crewed mission to board the world's first space station, Salyut 1 (Soyuz 10 had soft-docked, but had not been able to enter due to latching problems). The crew, Georgy Dobrov ...

Design

The two craft of the Soyuz 7K-OKS generation were modified from the original

Soyuz 7K-OK Soyuz 7K-OK was the first generation of Soyuz (spacecraft), Soyuz spacecraft and was flown between 1967 and 1971. The 7K-OK was used for the first ferry flights to the Salyut programme, Salyut space station program, beginning a long history ...

. The new "probe and drogue" docking mechanism, which was first used by these two missions, featured an internal docking hatch that allowed for the first time internal transfer between Soviet spacecraft. This "probe and drogue" docking mechanism introduced with Soyuz 7K-OKS is still in use today at the

International Space Station The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA ...

(ISS). The external toroidal fuel tank, a holdover from the original lunar mission models of the Soyuz, was dropped from the 7K-OKS since it was unneeded for Earth orbital flights.

Flights

The Soyuz 7K-OKS flew only twice,

and

. On its maiden flight, the Soyuz 7K-OKS successfully launched into Earth orbit, but failed to dock completely with the

Salyut 1 Salyut 1 (DOS-1) (russian: Салют-1) was the world's first space station launched into low Earth orbit by the Soviet Union on April 19, 1971. The Salyut program followed this with five more successful launches of seven more stations. The fi ...

space station. Upon reentry, the spacecraft encountered problems with toxic fumes. This generation of Soyuz spacecraft is notable for the first successful delivery of crew to the first space station

by Soyuz 11 – this success was however overshadowed by the death of the crew, who were killed when the capsule depressurised during the

re-entry Atmospheric entry is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet, or natural satellite. There are two main types of atmospheric entry: ''uncontrolled entry'', such as the entr ...

phase.

Missions

References

External links

Russia New Russian spaceship will be able to fly to Moon - space corp

* Mir Hardware Heritage ** David S.F. Portree,

', NASA RP-1357, 1995 ** Mir Hardware Heritage (wikisource)
Information on Soyuz spacecraft

{{Russian human spaceflight programs Crewed spacecraft Soyuz program Vehicles introduced in 1971