U.S. Air Force Lt. Col. Philippe Malebranche, F-16 pilot with the 177th Fighter Wing, prepares to stow aircrew flight equipment in his F-16C Fighting Falcon after a training mission during Thracian Star, a bilateral training exercise to enhance interoperability with the Bulgarian air force, at Graf Ignatievo Air Base, Bulgaria, on July 13, 2015. (U.S. Air National Guard photo by Master Sgt. Andrew J. Moseley/Released)