ELLSWORTH AIR FORCE BASE, S.D. – Tech. Sgt. Tywone Weston, 28th Maintenance Squadron aerospace propulsion test cell assistant NCO in-charge checks a B-1B Lancer General Electric F-101 turbofan engine for leaks, Oct. 6. The 28 MXS manages 138 F-101 engines to assist B-1 readiness. (U.S. Air Force photo/Senior Airman Corey Hook)