A UH-60 Black Hawk Helicopter flies over Airmen from the 455th Expeditionary Security Forces Squadron as they prepare for a mission at Bagram Airfield, Afghanistan, Aug. 18, 2012. Hundreds of Security Forces Airmen keep a constant vigil on Bagram, ready to deter, engage and defeat any potential threats. (U.S. Air Force photo/Capt. Raymond Geoffroy)