The 1st Maintenance Squadron propulsion flight’s testing facility, or “hush house,” is used to ensure the Pratt and Whitney F119 engine is working at its full capabilities before installing on a F-22 Raptor at Langley Air Force Base, Va., July 22, 2015. The F119 engine is the only operational fifth-generation fighter engine and the most advanced production engine. (U.S. Air Force photo by Airman 1st Class Derek Seifert/Released)