Senior Airman Quenton Richardson, 159th Maintenance Squadron crew chief, Louisiana Air National Guard, removes an external fuel tank on an F-15 Eagle during Red Flag 15-3 at Nellis Air Force Base, Nev., July 14, 2015. Crew chiefs are responsible for overseeing the day-to-day maintenance of aircraft including diagnosing malfunctions and replacing components to ensure the aircraft functions properly. (U.S. Air Force photo by Airman 1st Class Jake Carter)