Paul Hattendorf, a Lockheed Martin test pilot, flies AF-2, the second production F-35 Lightning II for the Air Force, during an airframe loads envelope expansion mission June 11, 2014, over Edwards Air Force Base, Calif. During a mission July 21 to 25, the 9th Air Refueling Squadron supported F-35s from Edwards AFB with aerial refueling while the fighters performed sensor fusion and data links test operations. (Photo courtesy of Tom Reynolds/Lockheed Martin).