U.S. Air Force Lt. Col. Jeff Stogsdill, 548th Combat Training Squadron assistant director of operations, answers questions about the B-52 Stratofortress from members of the 425th Fighter Squadron (FS), who are on temporary duty at Barksdale Air Force Base, La., in support of a Green Flag exercise, Sept. 23, 2011. The 425th FS, assigned to Luke Air Force Base, Ariz., provides advanced weapons and tactics training for Republic of Singapore F-16 pilots and maintenance personnel. Green Flag is an exercise designed to prepare pilots for combined, air, ground and electronic threat environments. (U.S. Air Force photo by Master Sgt. Greg Steele/Released)