U.S. Air Force Chief of Staff Gen. David L. Goldfein passes the Air Combat Command guidon to Gen. James M. Holmes during ACC’s Change of Command ceremony at Joint Base Langley-Eustis, Va., March 10, 2017. Holmes assumed command from Gen. Herbert “Hawk” Carlisle, who retired after 39 years of service to the Air Force. (U.S. Air Force photo/Senior Airman Kimberly Nagle)