Original caption, May 1974: “B-1 Engine Completes PFRT– General Electric’s F101 turbofan engine, powerplant for the Air Force’s new B-1 strategic bomber, is inspected between running cycles in a high-altitude test cell at Air Force Systems Command’s Arnold Engineering Development Center near Tullahoma, Tenn. The engine passed its Preliminary Flight Rating Test after approximately 80 hours of altitude testing at Arnold and 60 hours of endurance running at GE’s plant near Cincinnati. Four of the 30,000 pound-thrust-class engines will power the B-1 when it makes its initial flight later this year.” U.S. Air Force photograph, Arnold Engineering Development Center, Tullahoma, TN. MS-458, Dayton Daily News Archive, JHAN 21p.