U.S. Air Force Staff Sgt. Christopher Stell, a crew chief assigned to the 44th Aircraft Maintenance Unit, monitors an F-15C Eagle aircraft before flight operations during Cope Tiger 13 at Korat Royal Thai Air Force Base, Thailand, March 11, 2013. Cope Tiger is an annual multilateral aerial exercise designed to improve readiness and cooperation between U.S., Thai and Singaporean forces. (U.S. Air Force photo by 2nd Lt. Jake Bailey/Released)