U.S. Air Force Senior Airman Kyle Koski, 52nd Civil Engineer Squadron explosive ordnance disposal journeyman, Spangdahlem Air Base, Germany, provides over watch during Northern Challenge 16 exercise at Icelandic Coast Guard Keflavik Facility, Iceland, Sept. 19, 2016. The exercise focused on disabling improvised explosive devices in support of counter-terrorism tactics to prepare Partnership for Peace, NATO, and Nordic nations for international deployments and defense against terrorism. (U.S. Air Force photo by Staff Sgt. Jonathan Snyder)