Striker, a U.S. Department of Agriculture brown tree snake detector dog, inspects an aircraft prior to departure on Thursday, April 30, 2015, at Andersen Air Force Base, Guam. All Department of Defense aircraft, household goods, vehicles and cargo are required to be searched prior to departure in order to prevent the establishment of snakes in other regions. (Katrina M. Brisbin/U.S. Air Force)

Staff Sgt. Nathan Williams and Senior Airman Justin Caldwell, 19th Civil Engineer squadron firefighters inspect a simulated casualty as part of a major accident response inspection on April 22, 2015, in Jacksonville, Ark. (Harry Brexel/U.S. Air Force)

A U.S. Air Force F-16 Fighting Falcon from the 354th Fighter Wing at Eielson Air Force Base, Alaska, is refueled by a U.S. Air Force KC-135 Stratotanker from Fairchild Air Force Base, Wash., on May 4, 2015, during Red Flag-Alaska 15-2. (Shawn Nickel/U.S. Air Force)

U.S. airmen assigned to the 169th Fighter Wing along with family members run the first Life of a Warrior Run at McEntire Joint National Guard Base, S.C., on May 2, 2015. (Jorge Intriago/U.S. Air Force)

Staff Sgt. Zachary Lowery, 31st Security Forces Squadron security response team leader, practices room entry during a weeklong combat expertise training program at Aviano Air Base, Italy. (Austin Harvill/U.S. Air Force)