Mercury spacesuit

The MK IV Full Pressure Suit ensemble was also used extensively by the US Navy from about 1959 through the early 1970s in aircraft such as the F-4 Phantom, A-3/A-5/RA-5C Vigilante, and F-8 Crusader.

The suit was designed by Russell Colley (who designed and built the high-altitude pressure suit worn by aviator Wiley Post) as a means of providing an Earth-like atmosphere in the unpressurized high-altitude fighter jets developed by the U.S. Air Force and U.S. Navy after the Korean War.

The most severe test of the suit occurred during the record-setting balloon flight of Malcolm Ross and Victor Prather in the Strato-Lab V unpressurized gondola to 113,740 feet (34,670 m) on May 4, 1961.

[1] The only suit-related incident was an uncapped ventilation inlet valve which almost led to the drowning of astronaut Gus Grissom: at the end of the MR-4 mission the hatch cover blew off while in the Atlantic Ocean and the capsule began to fill with water, forcing Grissom to make an emergency exit without securing his suit for the recovery operations.

Since then, NASA has used either the David Clark Company, ILC Dover, Hamilton Sundstrand, or Oceaneering International for all pressure and spacesuit needs.