The Mark IV helmet was used by the United States Navy for many years as part of the Mark IV High Altitude Full Pressure Suit. The main compoinets of the hlemet consisted of a reinforced plastic hard shell, incorporating oxygen breathing, communications, and suspension equipment. An adjustable tinted sun visor was also provided. The Mark IV outfit was used with the Navy high-performance aircraft such as the F-8 Crusader and F-4 Phantom II, when operating above 50,000 feet. It was adopted by the United States Air Force with modifications and designated as the A/P 22S-3 suit. A further development of the suit and helmet was also used by the astronauts in the Mercury space program.
Transferred from the National Aeronautics and Space Administration
United States Navy Mark IV Full Pressure Flying Helmet; gold fiberglass shell with two plastic visors (one clear, one smoked); aluminum neck ring; chamois lined earphones; sage green nylon covered oxygen hose; internal microphone; black rubber lining with black rubber face ring seal; aluminum lining adjustment knob on right rear of helmet; United States Naval Aviator's badge decale with text "U.S. NAVY" on front of helmet; manufacturer's decal "B.F. Goodrich" rear of helmet; dark blue decal "USN" on rear of helmet; Firewel Co. oxygen regulator mounted externally on left rear of helmet.