U.S. Air Force F-16 Fighting Falcon aircraft assigned to the 18th Aggressor Squadron go through final checks prior to takeoff at Eielson Air Force Base in Alaska Feb. 10, 2014, en route to Andersen Air Force Base in Guam to support exercise Cope North 2014. Cope North is an annual air combat tactics, humanitarian assistance and disaster relief exercise designed to increase the readiness and interoperability of the U.S. Air Force, Japan Air Self-Defense Force and Royal Australian Air Force.