Reentry Capsule - Soyuz

Soyuz

The former Soviet Union suffered two disasters, and one near-disaster, all three involving the capsule during the de-orbit and reentry. Soyuz 1 ended in disaster when the parachutes failed to deploy and the capsule smashed into the earth at speeds over 300 mph, killing cosmonaut Vladimir Komarov. Soyuz 5 almost ended in disaster, when the reentry capsule entered the atmosphere on the wrong end – attributed to a failure of the equipment module to separate similar to that on the Vostok 1 flight. Luckily, the equipment module burned off the descent module and the capsule righted itself.

Soyuz 11 ended in disaster in 1971 when an equalization valve, used to equalize air pressure during the Soyuz final descent, prematurely opened in the vacuum of space, killing the three crew members, who were not wearing spacesuits. Subsequent flights, from Soyuz 12 to Soyuz 40, utilized a two-man crew because the third seat had to be removed for the pressure suit controls. The Soyuz T version restored the third seat.