On June 17, 1941, this detachment from the United States Army Air Corps graduated from the Casey jones School of Aeronautics. The USAAC was the aerial warfare service of the United States of America between July 2,1926 and June 20, 1941.
Prior to July 1926 the Air Corps was known as the United States Army Air Service. The Air Corps became The United States Army Air Forces on June 20, 1941, three days after this photo was taken. While still part of the army, the name change gave the air corps greater autonomy. In 1947, the Air Corps was legally abolished establishing the Department of the Air Force.