Three U.S. Air Force pilots from the 555th Fighter Squadron, Aviano Air Base, Italy, walk toward their aircraft at Graf Ignatievo Air Base, Bulgaria, Sept. 21, 2020. The pilots participated in Thracian Viper 20, a multilateral training exercise, which allows both U.S. Air Force Airmen and Bulgarian forces to extend joint warfighting capability through operational and tactical training. The 555th Fighter Squadron conducted air-to-air training with Bulgarian MiG-29s and air-to-surface training with Bulgarian Air Defense assets. (U.S. Air Force photo by Airman 1st Class Ericka A. Woolever)