U.S. Air Force Airmen from the 909th Aircraft Maintenance Unit prepare a KC-135 Stratotanker for pre-flight inspections April 20, 2017, at Kadena Air Base, Japan. The 909th Air Refueling Squadron performed refueling operations for Kadena’s F-15 Eagles going to Guam for Exercise Vigilant Ace. (U.S. Air Force photo by Senior Airman Lynette M. Rolen)