Flight suit

A flight suit is a full body garment, worn while flying aircraft such as military airplanes, gliders and helicopters. These suits are generally made to keep the wearer warm, as well as being practical (plenty of pockets), and durable (including fire retardant). Its appearance is usually similar to a jumpsuit. A military flight suit may also show rank insignia. It is sometimes used as a combat uniform in close quarters battle or visit, board, search, and seizure situations, for its practicality.

As aviation developed in unheated open cockpits, the need for warm clothing quickly became apparent, as did the need for multiple pockets with closures of buttons, snaps, or zippers to prevent loss of articles during maneuvers. Various types of flight jackets and pants coverings were developed and, during World War I, leather two-piece outfits were common among pilots to ward off the chill caused by propwash and the cold of low-oxygen high-altitude flying. Leather quickly became the preferred material due to its durability and the protection it offered against flying debris such as insect strikes during climb-outs and landings, and oil thrown off by the simple rotary and inline motors of the time. Australian aviator Frederick Sidney Cotton's experience with high level and low-temperature flying led Cotton in 1917 to develop the revolutionary new "Sidcot" suit, a flying suit which solved the problem pilots had in keeping warm in the cockpit. This flying suit, with improvements, was widely used by the RAF until the 1950s.

By the time World War II started in earnest, electrically heated suits were introduced by Lion Apparel in conjunction with General Electric for patrol and bomber crews who routinely operated at high altitudes above 30,000 feet, where air temperatures could get so cold that flesh could freeze instantly to any metal it touched. As enclosed and pressurized cabins came into operation, the necessity of bulky leather and shearling jackets and pants began to fade. For example, pilots, navigators, and bombardiers of a B-17 operating in Europe in 1944 comfortably wore their officer's uniforms under an A-2 flight jacket, due to the enclosed and heated cabin; but the waist gunners needed electrically heated suits, as they fired their guns through open window gunports. When the B-29 Superfortress was introduced in the fight against Japan, along with remote-controlled coordinated gun turrets, the fully pressurized crew cabin made bulky flight gear obsolete.

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