Republic's XF-84H turboprop fighter is said to be the fastest propeller-driven plane ever built. An Allison XT-40 jet engine is teamed with supersonic propeller to power the aircraft. The combination gives high speed and performance with economy of fuel. Length: 51 ft (15.5 m). Height: 15 ft (4.5 m). Span: 33 ft (10 m).
REPUBLIC AVIATION CORPORATION, FARMINGDALE, L.I., N.Y.
09/30/2006. Remarks by Johan Visschedijk: "The XF-84H was nicknamed "Thunderscreech". This is the second of two XF-84H-RE prototypes, the first was serialed 51-17059."