Launch Entry Suit

The Launch Entry Suit (LES), known as the "pumpkin suit", was a partial pressure suit worn by all Space Shuttle crews for the ascent and entry portions of flight from STS-26 (1988) to STS-65 (1994). It was completely phased out by STS-88 (late 1998) and replaced by the ACES suit. The suit was manufactured by the David Clark Company of Worcester, Massachusetts.

The LES was first worn by U.S. Air Force pilots in the mid-1970s, replacing a similar suit worn by SR-71 and U-2 pilots, and was identical to the suits worn by X-15 pilots and Gemini astronauts. Unlike the ACES suit, which is a full-pressure suit, the high-altitude suits were partial pressure suits, thus requiring a rubber diaphragm around the wearer's face. With the development of the Space Shuttle, and the inclusion of ejection seats on the Space Shuttle Columbia on the first four flights (STS-1 to STS-4), NASA decided to adopt modified versions of the suit; the modifications being the attachments to the parachute harness, and the adoption of inflatable bladders in the legs to prevent the crew from passing out during reentry. One other modification, a mount for prescription glasses, was incorporated for astronaut John W. Young, who wore modified bifocal reading glasses (resembling aviator sunglasses, but with the top portion, usually for distance seeing, being of regular glass, and the bottom, for reading, of the wearer's prescription) during the flight.

The four test flights, between April 1981 and July 1982, went without incident, and the pressure suits performed without any problems. With the termination of the test flight program, all flights from STS-5 to STS-51-L (the Challenger disaster) saw the crew wearing one-piece light blue flight suits, escape harnesses, and helmets similar to the pressure suit helmets, but fitted around the head with a clamshell-like closure. After Challenger, NASA, in need of an escape system, also required the reintroduction of the wearing of pressure suits during the launch and landing portions of the flight. The initial eight suits were navy blue, similar in color to the previous flight suits, the rest of the suits were bright orange to contrast against the dark blue ocean water they'd most likely be used in. The blue suits were never used on an actual mission.

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