Airman Austin Cheney, 363rd Training Squadron F-16 aircraft armament systems apprentice course student, prepares a pylon for a BRU-57/A sub-rack for installation. The sub-rack allows the pylon to hold two precision guided munitions that can weigh up to 1,000 pound each, instead of just one. Cheney and his classmates are on block eight of 12 and are scheduled to graduate on Jan. 3, 2018. (U.S. Air Force photo by Senior Airman Robert L. McIlrath)