A Navy Mark IV high-altitude pressure suit and helmet developed by the B. F. Goodrich Company and the US Navy for high-altitude pilots, best known for being modified by NASA to be used as the spacesuit worn for all Project Mercury manned spaceflights. The suit, dated May 1961, is a “Type Mk IV, Mod 2, Type 1A” and includes one hose attachment. It bears several “USN” patches and is labeled as size “Medium Long.” The Mark IV helmet included bears a B. F. Goodrich label affixed to the back along with silver, red, and gold decals, and has both clear and shaded visor attachments. Also includes the communication connection cable and original hardshell carrying case. In fine condition, with very little overall wear. Pressure suits were necessary to protect the astronaut in the event of a sudden depressurization of the cabin in the vacuum of space. Such suits were developed by both the US Navy and Air Force for the use of their pilots in high-altitude unpressurized fighter jets, and upon testing NASA preferred the Navy’s Mark IV suit as a platform. The most obvious modification NASA made was the replacement of the dark outer shell with aluminum-coated nylon for thermal control purposes, giving the suit a futuristic shiny silver appearance; most of the other changes also had to do with thermal and environmental control. An extremely desirable, well-preserved example of this significant breakthrough in aeronautic suit design.
