A U.S. Air Force KC-135 Stratotanker flown by the 912th Air Refueling Squadron from March Air Force Base, Calif., provides refueling capabilities to Royal Canadian Air Force CF-18s while both units participate in the Vigilant Shield 2017 Field Training Exercise 20 Oct., 2016, in the high arctic. VS17 is an annual exercise sponsored by The North American Aerospace Defense Command and led by Alaskan NORAD Region, in conjunction with Canadian NORAD Region and Continental NORAD Region, who undertake field training exercises aimed at improving operational capability in a bi-national environment. This year’s exercise sees NORAD building on previous years’ training successes when deploying air assets and personnel to the far north to exercise sovereignty operations in North America’s northern aerospace and in the high Arctic. This exercise provides crucial training opportunities for numerous military personnelwith a variety of aircraft and assets from Canada and the United States to improve interoperability and to demonstrate NORAD’s ability to defend North America. (U.S. Air Force Photo by Tech. Sgt. Gregory Brook)