Virginia Air National Guard Master Sgt. Russell Tilley, 192nd Maintenance Squadron aerospace propulsion technician, conducts a pre-test inspection on a Pratt and Whitney F119 engine at Langley Air Force Base, Va., July 22, 2015. The engine powers the F-22 Raptor and produces more thrust than any other current fighter jet engine. (U.S. Air Force photo by Senior Airman Kayla Newman/Released)