Soyuz 11

Soyuz 11 was the only crewed mission to board the world's first space station, Salyut 1. Cosmonauts Georgy Dobrovolsky, Vladislav Volkov and Viktor Patsayev launched from the Baikonur Cosmodrome on 6 June 1971, docked with the station on 7 June and lived aboard for about 22 days, setting a space endurance record that stood until the American Skylab 2 mission in 1973. They had replaced the original prime crew of Alexei Leonov, Valery Kubasov and Pyotr Kolodin after an X-ray raised a tuberculosis concern about Kubasov. The stay included smoke and a fire aboard the station, live television broadcasts and scientific work. The mission ended in disaster on 29 June 1971: a pressure equalisation valve between the orbital and descent modules was jolted open when the modules separated before re-entry, the cabin lost its air within moments, and all three men were found dead after the automatic landing in Kazakhstan. They remain the only humans known to have died above the Karman line. The Soyuz was redesigned to carry two cosmonauts wearing pressure suits, and the crew were buried in the Kremlin Wall Necropolis.