Trainees with the 315th Airlift Wing Development and Training Flight stand at attention during the 315th Airlift Wing’s Development and Training Flight unit training assembly weekend June 17, 2012 at Joint Base Charleston, S.C. DTF participation is mandatory for all newly enlisted Airmen and serves as part of their enlistment into the inactive Reserve while awaiting positions to open in Basic Military Training. (U.S. Air Force Photo/Staff Sgt. Shane Ellis)