Gemini Space suit

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The Gemini Space suit is a space suit worn by astronauts for launch, in-flight activities, including EVAs, and landing. It was designed by NASA based on the X-15 high-altitude pressure suit, and has been used since Gemini, in various forms, by the U.S. Air Force and NASA on U-2 and SR-71 Blackbird high-altitude flights and on the Space Shuttle. All Gemini spacesuits were developed and manufactured by the David Clark Company in Worcester, Massachusetts.

[edit] G3C and G4C Suits

The G3C and G4C suits were the primary spacesuits worn for all but the Gemini 7 mission. The G3C consisted of six layers of nylon (the innermost containing a rubberized nylon "bladder") and nomex, with a link net retaining layer and an outer layer of white nomex fabric. It had removable combat-style boots, also made of nomex fabric, along with a full-pressure helmet (containing a set of earphones and microphones) and gloves detachable by improved locking rings that allow easy rotation of the wrists. On Gemini 3 the G3C suit was worn by both Gus Grissom and John W. Young and was the only flight to use this suit.

The G4C suit was identical to the G3C suit, but came in two different styles. Both had additional layers of mylar insulation for temperature control (+250°F in direct sunlight and -250°F in shadow), but the commander's suit retained the removable boots, while the pilot's version had integrated boots and a detachable sun visor which clipped onto the helmet. The G4C suit was worn by all crews from Gemini 4 to its end and it was in this suit that Ed White made the first American spacewalk in 1965. Except for one modification, the incorporation of additional layers in the legs, as well as an outer layer of "Chromel-R" fabric on the Gemini 9A spacesuit worn by Eugene Cernan (he was to test the Astronaut Maneuvering Unit, which used hydrogen peroxide as its fuel), and the replacement of the plexiglas helmet faceplate with one made of polycarbonate plastic, the G4C suits remained unchanged until the last Gemini flight in 1966.

[edit] G5C Suits

For the 14-day Gemini 7 mission, both Frank Borman and Jim Lovell wore modified G3C suits for the mission, but incorporated several changes.

• Replacement of the pressure helmet and neck ring with a zippered hood incorporating a clear, fixed polycarbonate visor, with the astronauts wearing modified Navy-style aviator crash helments that incorporated the communication equipment (microphones and earphones)

• Additional zippers for in-flight adjustment, along with provisions for complete removal of the suit.

During the mission, Lovell was the first person to take his pressure suit off, which was achieved with great difficulty due to his size. Borman later was able to get his suit off and biomedical data collected during the flight revealed that astronauts would be more comfortable during the flight when wearing flight suits during "non-critical" phases of the mission. This lead to the wearing of such flight suits from Apollo 7 to the present day. This suit somewhat resembles the current Soyuz Sokol pressure suits worn by Russian-launched ISS crews.

[edit] After Gemini

After the ending of Gemini, the Gemini space suit was chosen by NASA for the initial Apollo "Block I" testing phase of the program. Since no dockings or EVAs were scheduled for the first manned Apollo flight, and with NASA searching for a suitable lunar EVA suit for the "Block II" phase of the program (a competition between ILC Dover, Hamilton Sundstrand, and David Clark), NASA decided to use the G3C as a base for the new "A1C" suit. Using the base G3C suit, but with a white nomex cover layer from the G4C and G5C suits, the new A1C suits had new electrical and enviornmental disconnects, a protective shell over the plexiglas visor (plexiglas was used instead of polycarbonate due to its expense), and with a launch escape system in place of ejector seats, a yellow-colored U-shaped inflatable "Mae West" PFD replaced the pilot parachute and its harness. Unfortunately, the Apollo 1 accident, which killed astronauts Grissom, White, and Roger Chaffee resulted in NASA cancelling the "Block I" program and starting with the flight of Apollo 7, all Apollo equipment, including spacesuits, was tested using the "Block II" configuration. This included the docking equipment on the Apollo CM and the ILC A7L space suit.

Since Apollo, the Gemini spacesuit was looked at for the Manned Orbiting Laboratory program, but it has since been used as the baseline for all high-altitude pressure suits worn by U.S. Air Force, and later by NASA as its current ACES pressure suit.