U.S. Air Force Staff Sgt. Andrew Martz, a KC-10 Extender aircraft flight engineer with the 908th Expeditionary Aerial Refueling Squadron, conducts a preflight check inside an aircraft on an air base in Southwest Asia Nov. 7, 2008, prior to a flight over Afghanistan. (DoD photo by Staff Sgt. Aaron Allmon, U.S. Air Force/Released)