Take cover
Airman 1st Class Scott Brown, 62nd Aerial Port Squadron, stays in the prone position during a simulated air attack during a mobility exercise Oct. 18, 2011, at Joint Base Lewis-McChord, Wash. The purpose of the mobility exercise, or MOBEX, is to evaluate a unit?s ability to meet wartime and contingency tasks of employing forces, sustaining forces and maintaining the ability to survive and operate in a deployed location. (U.S. Air Force photo/Staff Sgt. Frances Kriss)