Original: It was a component of the United States Army , divided functionally by executive order in 1942 into three autonomous forces : the Army Ground Forces , the Services of Supply ( which in 1943 became the Army Service Forces ) , and the AAF .
Simplified: Although other nations already had separate air forces independent of the army or navy ( such as the British Royal Air Force and the German Luftwaffe ) , the USAAF remained a part of the United States Army .