Pre-flight Checks U.S. airmen perform pre-flight checks on a U.S. Air Force KC-135T Stratotanker on the flightline before a refueling mission at Southwest Asia, Nov. 24, 2015. The airmen are assigned to the 340th Expeditionary Air Refueling Squadron. U.S. Air Force photo by Staff Sgt. Corey Hook SHARE: Download: Full Size (0.66 MB) Credit: Staff Sgt. Corey Hook VIRIN: 151124-F-ZU607-037.JPG Photo Gallery