A U.S. Air Force crew chief marshals a B-52H Stratofortress after a sortie at Barksdale Air Force Base, La., June 23, 2014. The sortie marked the final flight for Col. Marty Wilson, Director of 8th Air Force Standardization and Evaluation, before his retirement from the Air Force. (U.S. Air Force photo by Master Sgt. Jeff Walston/Released)