U.S. Air Force Airmen from the 177th Fighter Wing of the New Jersey Air National Guard are briefed by Lt. Col. Timothy Hassel, 119th Fighter Squadron commander, during Thracian Star, a bilateral training exercise to enhance interoperability with the Bulgarian air force at Graf Ignatievo Air Base, Bulgaria, on July 10, 2015. (U.S. Air National Guard photo by Master Sgt. Andrew J. Moseley/Released)