LANGLEY AIR FORCE BASE, Va. -- Command Master Chief Petty Officer Jon Port, helps prepare the grog for the enlisted dining in Dec. 11. The focus of the dining in was to celebrate the 50th anniversary of the rank of Chief Master Sgt. The rank was introduced into the United States Air Force Dec. 1, 1959. (U.S. Air Force photo/Staff Sgt. Jeff Nevison)