Twenty C-17 Globemaster IIIs participate in a Large Formation Exercise Dec. 21 over the coast of Charleston, S.C. The C-17s, assigned to the 437th and 315th Airlift Wings at Charleston AFB, were part of the largest formation in history from a single base and demonstrated the strategic airdrop capability of the Air Force. (U.S. Air Force photo/Master Sgt. Andy Dunaway)