The United States Air Force Air Demonstration Squadron "Thunderbirds" perform during the Grissom Air and Space Expo, Sept. 7, 2019, at Grissom Air Reserve Base, Ind. The Thunderbirds perform at more than 30 show sites each year, highlighting the pride, precision and professionalism of the Air Force. (U.S. Air Force photo by Senior Airman Andrew D. Sarver)
