Soyuz 21 mission is the designation for the flight of a Soviet Soyuz spacecraft to the Soviet space station Salyut 5 ( ALMAZ 3). It was the first visit by a Soyuz spacecraft in this space station and the 38th flight in the Soviet Sojusprogramm.
- Boris Valentinovich Wolynow ( second space flight), Commander
- Vitaly Mikhailovich Scholobow ( first space flight), flight engineer
Wolynow and Scholobow already formed the backup crew for Soyuz 15 Because of the problems encountered with the flight of Soyuz 16 was canceled and later performed with a different profile. Wolynow and Scholobow had to wait nearly two years until they were used.
- Vyacheslav Dmitrievich Sudow ( first space flight), Commander
- Valery Ilyich Rozhdestvensky ( first space flight ), flight engineer
The support team consisted of Anatoli Beresowoi, Yuri Glaskow Victor Gorbatko and Mikhail Lisun.
It was testing a manned military space station. These included Earth observations with Handspektrografen, Erdaufnahmen with various black and white and color films, infrared telescope, communication link beyond the reach of ground-based stations via a Molniya satellites and experiments for independent navigation of the station ( astrometric ). The visit to the space station coincided with the " Sibir " instead of maneuver of the Red Army in Siberia. The cosmonauts observed the exercise as part of the review of the station on their military competence. However, fundamental studies were also further medical-biological questions long space flights studied ( studies on guppies, experiment " wallflower " for measuring cardiac volume, germination experiments with plants). There were experiments on crystal development ( potash alum ) and to observe the Sun. Since the flight length of previous expeditions was not achieved, will speculate about reasons for termination - toxic gases or mental problems ( space sickness or homesick at Vitaly Scholobow ) may have played a role.