United States Army Air Force

USAAF is an abbreviation of United States Army Air Force.

Prior to becoming its own arm of the US Armed Forces, what is today the United States Air Force (USAF) was a part of the US Army. Before World War II it was a corps level organization known as the United States Army Air Corps, but its massive size increase during the war won it a complete organizational hierarchy of its own, and the name changed to United States Army Air Force, or USAAF.