Staff Sgt. Bruce Green, 773rd Civil Engineer Squadron pavements and construction equipment craftsman, repairs a crater during airfield damage repair training at the Pacific Air Forces’ Silver Flag site on Northwest Field, Guam, April 21, 2015. Airmen throughout PACAF participate in Silver Flag to exercise various expeditionary skills including ADR, where engineers provide a rapid, semi-permanent repair during combat operations to allow airfield operations to resume quickly. Green is assigned to Joint Base Elmendorf-Richardson, Alaska. (U.S. Air Force photo by Staff Sgt. Melissa B. White/Released)