PW-9

PW-9/FB
Naval variant, Boeing FB-5 of VF-6
Role	Pursuit fighter (PW-9) Carrier Fighter (FB series)
Manufacturer	Boeing
First flight	2 June 1923
Introduction	1923
Primary users	United States Army Air Service United States Navy U.S. Marine Corps
Number built	158
Developed from	Fokker D.VII

The Boeing Model 15 was a United States single-seat open-cockpit biplane fighter aircraft of the 1920s, manufactured by the Boeing company. The Model 15 saw service with the United States Army Air Service (as the PW-9 series) and with the United States Navy as a carrier-based fighter (as the FB series).

The design of the Model 15 was based on studies of the Fokker D.VII, of which 142 were brought back to the U.S. for evaluation as part of the Armistice Agreement ending World War I. Many of the features were similar. The Model 15 had a fuselage of welded steel tubing braced with piano wire, while the tapered single bay wings were fabric on a wooden frame, with spruce and mahogany wing spars and three-ply wood ribs. Wing struts were changed from the normal wood used in Boeing designs to streamlined steel tubes. The landing gear had a straight axle, streamlined into a small 16 in (410 mm) chord wing.

The original engine was a 300 hp (220 kW) Wright-Hispano, but when the 435 hp (324 kW) liquid-cooled Curtiss D-12 became available the aircraft was redesigned, moving the radiator from the nose to a "tunnel" under the engine. Along with some other minor design changes to the wings, the design was finalized on January 10, 1922.

The Army expressed interest in the new design, and agreed to provide armament, powerplants, and test the aircraft, while leaving Boeing the rights to the aircraft and design. The contract was signed on April 4, 1923 and the first prototype, designated XPW-9 for "Experimental Pursuit, Water-cooled engine", flew on June 2, 1923. The XPW-9 competed with the Curtiss Model 33 for contracts for a pursuit aircraft to replace the Thomas-Morse MB-3A in the United States Army Air Service.

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Wikipedia