The M-1951 Field Cap was part of the updated M1951 uniform designed for the war in Korea. Its components were intended for all weather conditions but was particularly aimed to be effective in extreme cold weather, wet or dry.
Field kitchen for the 43d Transportation Truck Company in Uijongbu, Korea, 1951.
The M-1951 field cap, or fatigue hat, is formally known as the "Cap, Field, Cotton, Wind Resistant, Poplin, M-1951". This field cap was a direct design derivative of the cap originally adopted in 1943 as part of the M1943 field uniform that included the M1943 Field Jacket and matching M-1943 Field Cap. The M-1951 model had a longer visor and the color changed to OG-107, a different shade of olive green. The M-1951 field cap was intended to be, and actually became, an all-purpose item that could be worn in a variety of climates and under combat conditions. For use in the winter, the cap had a flannel-lined fold-down panel that covered the ears and back of the head. It was soft enough to be worn underneath the liner of the M1 steel helmet without adjusting the liner suspension.
The M-1951 field cap was universally liked because it was comfortable and practical, and afforded a reasonable amount of protection from the elements. It was produced through the late 1950s and was worn extensively during the Korean War both in garrison and in the field when conditions did not require the protection of a helmet. The cap also was used to some extent in combat by units performing special operations and reconnaissance patrols, which led to the cap being unofficially designated a "patrol cap" by the U.S. Army Rangers.
The soft comfort of the M-1951 field cap led to a reaction from officers who considered it to be too slovenly for a proper soldierly appearance. Orders were issued to stiffen the cap with cardboard and to use starch as well as ironing to keep it wrinkle free. This was not really possible with the M-1951 which insisted on a relaxed look. The widespread but unofficial Ridgeway Cap was the solution to this Army dilemma.
U.S. advisors in Vietnam, 1963-1964. M-1951 field cap is still worn with 1950s style OG-107 fatigues (left and center) or newly issued Jungle Fatigues (right), until replaced by the Cap, Field (Hot Weather) baseball cap.
The M-1951 cap, including the Ridgeway "coffee can" cap, were superseded early in the Vietnam War period by the Cap, Field (Hot Weather) which is styled like a baseball cap. However, the latter cap was unpopular and when superseded by the BDU uniform, the M-1951 (or M-1943) style field cap made a comeback with the similarly styled Camouflaged BDU Uniform Patrol Cap.
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