U.S. Air Force Airman 1st Class Nathan Wilson, 633rd Communications Squadron radio frequency transmission system technician, awaits medical attention during an active-shooter exercise at Langley Air Force Base Va., Nov. 19, 2013. In the simulated scenario, Wilson was shot after refusing to sell a trailer to an Airman who recently returned from deployment. (U.S. Air Force photo by Airman Areca T. Wilson/Released)