POWER PLANT: One Westinghouse 24C turbojet engine, rated at 1,360 kp
PERFORMANCE: 535 mph
COMMENT: The design for a fast carrier-based jet fighter was put forward by Grumman Company in November 1944. This small and aerodynamic clean cantilever-winged fighter was to be armed with either four 20mm cannon or six 0.5 in machine guns across the nose. The wings were not of folding type. The aircraft was to be powered by a single Westinghouse 24C turbojet engine delivering app. 1,300 kp thrust, but was still under development. It was the first jet fighter project of Grumman and it is not clear why this promising project was not pursued. However, after WW II the general design influenced the development of the Grumman F9F “Panther”, the Company’s first turbojet engine powered fighter showing better performance compared to the McDonnell FD-1 “ Phantom”, the US Navy’s first “pure” turbojet fighter.
COMMENT: There is some evidence that in the mid 1940’s the Boeing Company was working on a fighter project , named Project B.360, with an oval shaped wing, well suited for Short Take-Off/Landing (STOL) operations on carrier decks. The forerunner was the Chance Vought V-173 Flying Pancake demonstrator as well as the two prototypes of the Chance Vought XF5U-1. The B.390 differed from the Vought design in powering with one piston engine driving counter-rotating three-bladed propellers at the airplane‘s nose. No further details are known as well as the designation Boeing XF9B Flying Flapjack remains unclear.