Fourth and fifth-generation U.S. Air Force aircraft fly in a training airspace during ATLANTIC TRIDENT 17 near Joint Base Langley-Eustis, Va., April 26, 2017. Both generations of aircraft from the U.S. Air Force, French air force and Royal air force participated in the exercise to provide differing capabilities needed in a highly contested airspace. (U.S. Air Force photo/Staff Sgt. Natasha Stannard)