Security forces Airmen move to another position for cover to provide security while the injured are being evacuated after a simulated explosion of an improvised explosive device disables a vehicle in their convoy during a pre-deployment training exercise conducted by the U.S. Air Force Expeditionary Center's 421st Combat Training Squadron at Joint Base McGuire-Dix-Lakehurst, N.J. on September 15, 2009. (U.S. Air Force photo/Tech. Sgt. Paul R. Evans)