A U.S. Air Force F-35A Lightning II aircraft assigned to Hill Air Force Base, Utah, is refueled by a 100th Air Refueling Wing KC-135 Stratotanker during a flight to Estonia, April 25, 2017. The F-35s participated in a first-ever flying training deployment to Europe, and the forward deployment to Estonia allowed Airmen to better understand NATO's current infrastructure and strengthen interoperability with allies.