Salyut 5 Salyut 5 ( meaning " Salute 5 " ) , also known as OPS - 3 , was a Soviet space station . Launched in 1976 as part of the Salyut program me , it was the third and last Almaz space station to be launched for the Soviet military . Two Soyuz missions visited the station , each manned by two cosmonauts . A third Soyuz mission attempted to visit the station , but failed to dock , whilst a fourth mission was planned but never launched . Launch . Salyut 5 was launched at 18 : 04 : 00 UTC on 22 June 1976 . The launch took place from Site 81 / 23 the Baikonur Cosmodrome in the Kazakh Soviet Socialist Republic , and used a three - stage Proton - K 8K82K carrier rocket with the serial number 290 - 02 . Upon reaching orbit , Salyut 5 was assigned the International Designator 1976 - 057A , whilst the North American Aerospace Defense Command gave it the Satellite Catalog Number 08911 . Spacecraft . Salyut 5 was an Almaz spacecraft , the last of three to be launched as space stations after Salyut 2 and Salyut 3 . Like its predecessors , it was long , with a maximum diameter of . It had a habitable interior volume of , and a mass at launch of . The station was equipped with a single docking port for Soyuz spacecraft , with the Soyuz 7K - T being the configuration in service at the time . Two solar arrays mounted laterally at the same end of the station as the docking port provided it with power . The station was equipped with a KSI capsule to return research data and materials . Salyut 5 carried Agat , a camera which the crews used to observe the Earth . The German " Kristall " furnace was used for crystal growth experiments aboard the station . Operation . Four manned missions to Salyut 5 were originally planned . The first , Soyuz 21 , was launched from Baikonur on 6 July 1976 , and docked at 13 : 40 UTC the next day . The primary objective of the Soyuz 21 mission aboard Salyut 5 was to conduct military experiments , however scientific research was also conducted , which included studying aquarium fish in microgravity and observing the sun . The crew also conducted a televised conference with school pupils . Cosmonauts Boris Volynov and Vitali Zholobov remained aboard Salyut 5 until 24 August , when they returned to Earth landing 200 km southwest of Kokchetav . The mission had been expected to last longer , however the air within Salyut 5 became contaminated , which affected the crew ' s psychological and physical condition , necessitating an emergency landing . On 14 October 1976 , Soyuz 23 was launched carrying Vyacheslav Zudov and Valery Rozhdestvensky to the space station . During approach for docking the next day , a faulty sensor incorrectly detected an unexpected lateral motion . The spacecraft ' s Igla automated docking system fired the spacecraft ' s manoeuvring thrusters in an attempt to stop the non - existent motion . Although the crew was able to deactivate the Igla system , the spacecraft had expended too much fuel to reattempt the docking under manual control . Soyuz 23 returned to Earth on 16 October without completing its mission objectives . The last mission to Salyut 5 , Soyuz 24 , was launched on 7 February 1977 . Its crew consisted of cosmonauts Viktor Gorbatko and Yury Glazkov , who conducted repairs aboard the station and vented the air which had been reported to be contaminated . Scientific experiments were conducted , including observation of the sun . The Soyuz 24 crew departed on 25 February . On 26 February the KSI reentry capsule was ejected from the station for recovery . The fourth planned mission , which would have been designated Soyuz 25 if launched , was intended to visit the station for two weeks in July 1977 . It would have been crewed by cosmonauts Anatoly Berezovoy and Mikhail Lisun ; the backup crew for the Soyuz 24 mission . The mission was cancelled after higher fuel consumption than expected caused fuel reserves aboard Salyut 5 dropped to a level at which the mission could not have been safely completed . The spacecraft which was constructed for the Soyuz 25 mission was reused for the Soyuz 30 mission to Salyut 6 . Since it could not be refuelled , and no longer had the fuel to sustain manned operations , Salyut 5 was deorbited on 8 August 1977 , and broke up as it reentered the Earth ' s atmosphere .