U.S. Air Force Senior Master Sgt. Deangelo Lee, 51st Operations Support Squadron Air Traffic Control Airfield Landing Systems superintendent, helps disassemble an instrument landing system at Osan Air Base, Republic of Korea, June 22, 2017. The ILS enables aircraft to make precision landings when a pilot is unable to establish visual contact with the runway. (U.S. Air Force photo by Airman 1st Class Gwendalyn Smith)