A Bulgarian air force MiG-29 participates in exercise Thracian Viper 20, Sept. 23, 2020, at Graf Ignatievo Air Base, Bulgaria. Thracian Viper 20 allowed both U.S. 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)