A U.S. Army UH-60 Black Hawk helicopter conducts an engine run-up in the falling snow A U.S. Army UH-60 Black Hawk helicopter with Alpha Company, 5th Battalion, 101st Combat Aviation Brigade conducts an engine run-up in the falling snow of a winter storm at Bagram Airfield in the Parwan province of Afghanistan on Dec. 27, 2012. SHARE IMAGE: Download Image: Full Size (0.06 MB) Photo By: VIRIN: 664172-F-WFK76-210.jpg Photo Gallery