Two U.S. Air Force A-10C Thunderbolt IIs, a P-51 Mustang and a P-40 Warhawk fly in formation during the 2017 Heritage Flight Training and Certification Course at Davis-Monthan Air Force Base, Ariz., Feb. 10, 2017. The modern aircraft that participated in this year's HFTCC were the F-35 Lightning II, the F-22 Raptor, F-16 Fighting Falcon and the A-10C Thunderbolt II. (U.S. Air Force photo by Airman 1st Class Mya M. Crosby)