Airmen from various civil engineer units across the country, including about 30 Reservists from the 446th Civil Engineer Squadron, McChord Field, Wash. arrived at Tyndal Air Force Base, Fla., May 21, 2011 for the start of Silver Flag 2011. The week-long exercise provides civil engineer Airmen with contingency training free from home station constraints, and is designed to improve readiness ability. (U.S. Air Force photo by Staff Sgt. Grant Saylor/Released)