James continued civilian pilot training under the government-sponsored Civilian Pilot Training Program. He then enlisted in the Aviation Cadet Program of the United States Army Air Forces on January 18, 1943, receiving his commission as a second lieutenant and pilot wings at Tuskegee Army Airfield, Alabama, on July 28, 1943. He remained at Tuskegee as a civilian instructor pilot in the Army Air Corps later that July. Throughout the remainder of the war James trained pilots for the all-Black 99th Pursuit Squadron.