U.S. Air Force Airman 1st Class Brian Dowling, 27th Aircraft Maintenance Unit crew chief, checks an F-22 Raptor’s wing lights during Red Flag 17-1 at Nellis Air Force Base, Nev., Jan. 26, 2017. Checking the lights is a part of preflight inspections that ensure the aircraft’s instruments are in safe working order to fly. (U.S. Air Force photo by Staff Sgt. Natasha Stannard)