A U.S. Air Force KC-10 Extender aircraft from the 9th Air Refueling Squadron out of Travis Air Force Base, Calif., flies in to refuel from a KC-135R Stratotanker aircraft assigned to the 336th Aerial Refueling Squadron Aug. 4, 2009, over March Air Reserve Base, Calif.
(DoD photo by Staff Sgt. Daniel St. Pierre, U.S. Air Force/Released). Original public domain image from Flickr