Status: operational 1953.
It used the K-1 helmet, A2 adapter, and C-1 assembly with an F-1 regulator (0.87 l bottle at 120 bar) as an oxygen source. Fired automatically by aneroid at 13 km. Used T block to hook aircraft oxygen system with C-1 assembly backup. Hawks pressure compensated valve in K-1 helmet assembly. David Clark Company.
The S-2 partial pressure suit evolved originally for use in bomber aircraft although it was also used in experimental aircraft test projects. In 1951 the US Air Force authorized limited production of the S-2 suit for certain projects, but it was the T-1 suit which figured most prominently in the first high altitude jet and rocket propelled aircraft experiments of the late 40s and early 50s
|S-4 American pressure suit, operational 1955. The S-4 was a modified S-2 partial pressure suit, no anti-G, chest bladder incorporated for ease of breathing.|
|MC-1 American pressure suit, operational 1956. Modified S-2 partial pressure capstan suit with chest breathing bladder, 12 sizes, high altitude, fighters and bombers, smaller capstan in torso area, pressure gloves, K-1 or MB-5 helmet, David Clark Company.|