A U.S. Air Force F-16 Fighting Falcon assigned to the 555th Fighter Squadron, Aviano Air Base, Italy, flies over Graf Ignatievo Air Base, Bulgaria, during exercise Thracian Viper 20, Sept. 24, 2020. Thracian Viper 20 enhances successful partnering activities, which result in progressive relationships and lead to tangible, mutual benefits during peacetime, contingencies and crisis, through actions such as regional security, access and coalition operations. (U.S. Air Force photo by Airman 1st Class Ericka A. Woolever)