U.S. Air Force Maj. Gen. H.D. Polumbo, 9th Air Force commander, passes the guidon to Col. Caroline Miller, 633rd Air Base Wing incoming commander, during a change of command ceremony at Langley Air Force Base, Va., July 13, 2015. Miller assumed command of more than 9,000 military and civilian personnel across Joint Base Langley-Eustis. (U.S. Air Force photo by Senior Airman Kayla Newman/Released)