B-52 Stratofortress aircrew from Barksdale Air Force Base, La. prepares for takeoff April 17, 2016 at Minot AFB, N.D. in preparation of Constant Vigilance 2016, an annual Air Force Global Strike Command training event that exercises the command’s ability to support its conventional and nuclear missions. This exercise included simultaneous elements testing AFGSC’s policies, training and techniques at tactical and operational levels. (U.S. Air Force photo/Airman 1st Class Jessica Weissman)