Gen. Raymond Johns, Air Mobility Command commander, presents the 18th Air Force guidon to Lt. Gen. Darren McDew signifying the begin of his tenure as the 18th Air Force commander during a change of command ceremony at Scott Air Force Base, Ill., Aug. 6, 2012. Prior to his current assignment, McDew was the Commander, Air Force District of Washington at Joint Base Andrews, Md. The outgoing commander, Lt. Gen. Mark Ramsay, has accepted assignment as Director, Joint Staff Force Structure, Resources and Assessment Directorate, the Pentagon. (U.S. Air Force photo/Staff Sgt. Ryan Crane)