Unmanned Salyut Class Soyuz
Following the fatal mishap with Soyuz 11, the Soyuz underwent some design changes. There were two test flights before the next manned mission, Soyuz 12.
Kosmos 496, 26 June - 2 July 1972. Unmanned test of the redesigned Soyuz. It did not dock with any space station. Kosmos 496 retained the solar arrays from earlier Soyuz vehicles.
Kosmos 573, 15-17 June 1973. A second unmanned test of the Soyuz ferry. This version did not retain the solar arrays. Like the previous test, there was no space station docking.
Intervening between the successful Soyuz 12 and Soyuz 13 flights was another Soyuz test.
Kosmos 613, 30 November 1973 - 29 January 1974.This was a long duration orbital storage test of the Soyuz ferry in preparation for long term stays at a space station.
In 1978/79, there were two test flights of the new Soyuz T ferry.
Kosmos 1001, 4-15 April 1978. This was the first unmanned Soyuz T test.
Kosmos 1074, 31 January - 1 April 1979. This was a long duration Soyuz T test prior to the first Soyuz T (Soyuz T-1) flight to dock (unmanned) at Salyut 6.
Page last modified: 26 February 2026 16:58:37.