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Shenzhou 5 reentry capsule

The reentry capsule is the part of the Soviet/Russian Soyuz or Chinese Shenzhou spacecraft that returns to Earth after a space flight. The reentry capsule, which is shaped like that of an old-fashioned automobile headlight, contains the spacecraft's instrument panel, limited storage space, and seats for up to 3 crew members.

The reentry capsule is the "middle" module of the three-part Soyuz or Shenzhou spacecraft – the orbital module is located at the front of the spacecraft, with the service or equipment module attached to the rear. The reentry capsule, like that of the Apollo command module, has no reusable capabilities, thus each spacecraft is flown once and then "thrown away" (usually sent to museums). A feature in the landing system allows the use of a single parachute and "braking rocket," thus the heatshield is dropped from the spacecraft similar to the landing bag deployment on the U.S. Mercury spacecraft.

Few details are known about the Shenzhou reentry capsule, except that it uses some technology from the Soyuz TM design. The new Soyuz TMA spacecraft, now used solely for International Space Station flights, had its couches modified to allow for taller crewmembers to fly, and features "glass cockpit" technology similar to that found on the Space Shuttle and newer commercial and military aircraft.

Although no Chinese casualties have occurred on the few flights of the Shenzhou reentry capsule, 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 of the descent module and the capsule righted itself.

Soyuz 11 ended in disaster 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.