RAF Mildenhall, England -- A NATO E-3 Sentry from Geilenkirchen NATO Air Base receives fuel from a U.S. Air Force KC-135 Stratotanker assigned to the 100th Air Refueling Wing, RAF Mildenhall, England, over Germany, July 17, 2020. The 100th ARW is the only permanent U.S. air refueling wing in the European theater, providing the critical air refueling "bridge" which allows the Expeditionary Air Force to deploy around the globe at a moment's notice.