Luke AFB F-35A Lightning II at Dover AFB
Two F-35A Lightning II aircraft from Luke Air Force Base, Arizona, sit on the flight line at Dover AFB, Delaware, Feb. 18, 2020. Two F-35As recently returned from participating in the HX Challenge held near Tampere, Finland. During the HX Challenge, five different aircraft were tested for seven days, in Finnish weather conditions, to assess their ability to replace the current fleet of Finnish air force FA-18C and FA-18D Hornets. (U.S. Air Force photo by Senior Airman Christopher Quail)