The 315th Air Division is an inactive United States Air Force formation. Originally designated the 315th Bombardment Wing, it was activated in July 1944 at Peterson Field, Colorado as a command and control organization for four very heavy B-29 Superfortress bombardment groups. It supervised the 16th, 331st, 501st and 502nd Bombardment Groups in the Mariana Islands during the last stages of the Second World War. Its last assignment was with Pacific Air Forces, based at Tachikawa Air Base, Japan. The division was inactivated in April 1969.