Final checks
U.S. Air Force Staff Sgt. Nicholas Nelson, a crew chief with the 23d Aircraft Maintenance Squadron, 74th Aircraft Maintenance Unit, performs post-flight inspections on an an A-10C Thunderbolt II at Nellis Air Force Base, Nev., July 16, 2012, during exercise Red Flag 12-4. The crew chief's walk around begins two and a half hours before the pilot shows up, and they complete another walk around inspection with the pilot before takeoff. (U.S. Air Force photo by Master Sgt. Sonny Cohrs/Released)