Royal Air Force Senior Craftsman Mark Butler, avionics technician, attaches Hydrant Mobile Refueling equipment to an RAF E-3 aircraft at Langley Air Force Base, Va., March 7, 2012. Personnel at Langley are testing the new fuel delivery system that could revolutionize flightline operations and save the Air Force millions of dollars. (U.S. Air Force photo by Airman 1st Class Kayla Newman/Released)