U.S. Air Force Staff Sgt. Curtis Morgan and U.S. Air Force Senior Airman David Hartley, Maintenance Operations Center controllers, monitor flight line operations at Spangdahlem Air Base, Germany, March 25, 2015. The MOC has three eight-hour shifts during the work week to maintain 24-hour operations. (U.S. Air Force photo by 2nd Lt Meredith Mulvihill/Released)