Boeing Model 15 The Boeing Model 15 was a United States open - cockpit biplane single - seat 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 ) . Design and development . The design of the Model 15 was based on studies of the Fokker D . VII , 142 of which 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 chord wing . The original engine was a Wright - Hispano , but when the 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 - 3 A in the United States Army Air Service . Ultimately , both models were accepted ; the Curtiss aircraft was designated PW - 8 and the Model 15 PW - 9 . The Air Service preferred the PW - 9 , which outperformed the PW - 8 in all performance aspects except speed , and was built on a more rugged and easier to maintain design , ordering 113 aircraft ( only 25 PW - 8s were procured ) . A naval version was also developed , designated " FB " , and 44 aircraft produced . Operational history . Deliveries of the first 25 PW - 9s began on October 30 , 1925 . Boeing delivered a total of 114 PW - 9s of all variants including prototypes to the United States Army Air Corps between 1925 and February 1931 . Virtually all PW - 9s served with overseas units , in Hawaii with the 5th Composite Group at Luke Field and later the 18th Pursuit Group at Wheeler Field , and in the Philippines with the 4th Composite Group at Clark Field , Luzon . PW - 9s equipped the 3rd , 6th , and 19th Pursuit Squadrons between 1925 and 1931 . The FB - 1 , of which the Navy ordered 16 but received only 10 between December 1 and 22 , 1924 , was not modified for naval operations ( for instance , no arresting hook ) , and was assigned to Marine Corps squadrons VF - 1M , VF - 2M , and VF - 3M , being deployed to China in support of the Marine Expeditionary Force . Two additional planes — designated FB - 2 — were altered to operate on the carrier with the addition of arresting gear and a straight - across axle for the landing gear . These went into service with VF - 2 in December 1925 . Generally satisfactory results led to an order for 27 FB - 5s , which became the Navy ' s first fighters intended specifically for carrier operation . They were upgraded to 525 hp Packard 2A - 1500 engines , and sported a row of hooks on the bottom of the axle , used to guide the plane via cables on the deck . The FB - 5 first flew October 7 , 1926 and was delivered to the Navy beginning in the following January , carried on barges in Puget Sound from Boeing ' s factory to " Langley " anchored in Seattle ' s harbor . Hoisted aboard , their first official flights were from the carrier ' s deck .