U.S. Air Force Airman 1st Class Gregory Koenig, 94th Aircraft Maintenance Unit, checks an identification card at Langley Air Force Base, Va., March 14, 2012. The 633rd Security Forces Squadron trains augmentee gatekeepers to protect the base from unauthorized personnel by using proper entry-control procedures. (U.S. Air Force photo by Airman 1st Class Kayla Newman/Released)