The three men lost in space were Georgy Dobrovolsky, Vladislav Volkov, and Viktor Patsayev.
Georgy Dobrovolsky, Vladislav Volkov, and Viktor Patsayev, arrived at the space station on June 7th 1971 and departed into space on June 29th 1971.
Sadly the mission ended disaster as the crew capsule depressurized during the preparations for their re entry into earth, which killed all 3 people on board.
Georgy Dobrovolsky, Vladislav Volkov, and Viktor Patsayev were the only humans to have currently died in space.
The original prime crew for the Soyuz 11 consisted of Alexei Leonov, Valery Kubasov, and Pyotr Kolodin.
A medical X-ray examination that occured 4 days before launch suggested that Kubasov might have tuberculosis, and according to the mission rules, the prime crew was replaced with the backup crew.
For Dobrovolsky and Patsayev, this was to be their first space mission.
And after the failure of Salyut 2 to orbit, Kubasov and Leonov were reassigned to Soyuz 19 for the Apollo-Soyuz Test Project in 1975.
The Soyuz 7K-OKS spacecraft was launched on 6 June 1971, from the Baikonur Cosmodrome in the central Kazakh Soviet Socialist Republic, and used the callsign Yantar (Amber).
And several months earlier, the first mission to the Salyut, Soyuz 10, had failed to successfully dock with the station.
During the first day of the flight, maneuvers were made to effect a rendezvous with the uncrewed Salyut (1971-032A).
When Soyuz 11 was 6 to 7 kilometres (3.7 to 4.3 mi; 3.2 to 3.8 nmi) from Salyut, automatic devices took over, and in 24 minutes closed the gap between the two ships to 9 metres (30 ft) and reduced the relative speed difference to 0.2 metres per second (0.66 ft/s).
The control of the ships went from automatic back to manual at 100 metres (330 ft).
Docking also took 3 hours 19 minutes to complete and involved making the connection mechanically rigid, engaging various electrical and hydraulic links, and establishing air-tight seals before locks could be opened.
When the pressure was equalized between the ships, the locks were opened and all three members of the crew passed into Salyut 1.