Article

The Soyuz 11 mission concluded on June 30, 1971, with the tragic deaths of cosmonauts Georgi T. Dobrovolski, Vladislav N. Volkov, and Viktor I.

Patsayev. They had spent 23 days in space on the first experimental space station but died from decompression caused by a faulty breathing valve just before reentry. Upon landing in Kazakhstan, the retrieval team found the cosmonauts dead, with symptoms indicating a rapid drop in air pressure. This incident marked the first and only deaths in outer space during a mission, resulting in significant scrutiny and analysis of the event.