They became the world's first space station crew aboard Salyut 1, but died of asphyxiation because of an accidentally opened valve.

Dobrovolsky, Viktor Patsayev and Vladislav Volkov flew on the Soyuz 11 mission and were the world's third crew to die during a space flight.

[2] It was discovered that a valve had opened just prior to leaving orbit that had allowed the capsule's atmosphere to vent away into space, suffocating the crew.

[3] Dobrovolsky's ashes were placed in an urn in the Kremlin Wall Necropolis on Red Square in Moscow.

[4] Among the pallbearers were Alexei Leonov (who had been the prime-crew commander scheduled to launch on Soyuz 11), Vladimir Shatalov, Andriyan Nikolayev, and American astronaut Thomas P.