Tech. Sgt. Jason Umlauf, a 52nd Civil Engineer Squadron explosive ordnance disposal craftsman, sweeps an area with a mine detector during exercise Northern Challenge 16 in Keflavik, Iceland, Sept. 19, 2016. The exercise focused on disabling improvised explosive devices in support of counterterrorism tactics to prepare Partnership for Peace, NATO, and Nordic nations for international deployments and defense against terrorism. (U.S. Air Force photo/Staff Sgt. Jonathan Snyder)