10/31/2010. Remarks by Johan Visschedijk: "Two Model 450-67-27 B-47Bs (s/n 51-2046, 51-2103) were converted to XB-47D to serve as test beds for the Wright YT-49-W-1 turbo-prop engines. One of these was installed in place of the paired J-47s in each inboard nacelle. The outboard J-47-GE-23 jets were retained. To absorb the equivalent 9,710 shp of the T-49, four extremely wide blades were used on the 15 ft (4.57 m) diameter propellers. No armament was fitted.
Empty weight was 79,800 lb (36,197 kg), and take off gross weight was 184,428 lb (83,655 kg). Maximum speed was 597 mph (961 kmh) at 13,500 ft (4,115 m), the fastest achieved in level flight by a propeller-driven aircraft, and service ceiling was 33,750 ft (10,287 m). Rate of climb at normal power was 2,910 ft (887 m)/min.
