Airmen assigned to the 36th Aircraft Maintenance Unit push an F-16 Fighting Falcon assigned to the 36th Fighter Squadron inside a hardened facility Nov. 4, 2015, at Osan Air Base, Republic of Korea. The 36th FS is executing both day and night sorties during Vigilant Ace 16, challenging maintenance members to work around the clock in order to meet required mission sets. Vigilant Ace 16 is a large-scale exercise designed to enhance the interoperability of the U.S. and Republic of Korea Air Forces. (U.S. Air Force photo/Staff Sgt. Benjamin Sutton)