Students in the Advanced Contingency Skills Training Course respond to "enemy fire" during training on a Fort Dix, N.J., range on May 11, 2009. The training, taught by the U.S. Air Force Expeditionary Center's 421st Combat Training Squadron on Fort Dix, prepares Airmen for upcoming deployments. (U.S. Air Force Photo/Tech. Sgt. Scott T. Sturkol)