The Service Cap was the correct hat for use with the Service Coat, early in World War II. It was officially replaced by the Garrison Cap after 1941, but in fact continued in use whenever a more dress appearance was desired.
Col. Carroll D. Hudson, Commanding Officer, Redstone Arsenal, 26 February 1944.
There were these main distinctions among the Service Caps used in World War II:
Cap, Service, Enlisted Man's
Cap, Service, Officer's
U.S. Army, U.S. Army Air Corps, and USMC versions
U.S. Army Service Cap
The Officer's Service Cap bore the U.S. Coat of Arms in gold colored metal (top photo on this page and left). It mas made in dark OD shade wool (top photo) as well as in light shade cotton khaki material (photo, left). The Enlisted Man's Service Cap was very similar, but the cap device was a disk with the U.S. Coat of Arms on it. Both Officer and EM models had a leather brim with a leather chin strap fastened to the hat with two buttons. The chin strap was seldom used and served mainly as a decoration.
These caps were often procured by individuals from the PX or from private sources serving the military. Magazines in the WW II period carried ads for Service Hats from Stetson, Dobbs and other hatmakers.
U.S. Army Air Corps Service Cap
The USAAC wore the same Service Cap as the Army they were part of, but crews would remove the stiffener that kept the lower rim vertical. This resulted in a crushed look and made it easier to wear headphones over the cap. The dashing pilots, romanticized in print and movies, are often seen with such caps as an essential part of the look.
The world-wide scope of the Air Corps in World War II spread the use of the Service Cap for pilots. Although garrison caps, baseball caps, knit caps and other headgear were worn by the pilots and crew, many preferred the Service Cap even though it was less comfortable. Pilots were officers, with rare exceptions, so the Officer's Model was the correct cap, as in the photo on the right, taken at North American Aviation's Inglewood, California plant in a B-25 bomber, in October 1942.
U.S. Marine Corps Service Cap
The USMC Service Cap was similar in design to the Army version, but used either khaki or forest green cloth, matching USMC summer or winter uniform colors. The visor and leather straps were in black. A metal USMC "Eagle, Globe and Anchor" was afixed to the front of the Enlisted Man's and Officer's caps, as in the photo to the left of a Marine Sgt. during World War II. Caps of similar design were also part of Marine Officer's dress uniforms, summer (white) and winter (blue).
Service Cap Covers
Several covers were made to protect the Service Cap in wet weather. These resembled shower caps, a thin plastic round shape with an elastic edge that slipped over the hat brim. There was also a cotton khaki cover that would slip over an OD Service Cap for use with the khaki summer uniform.
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