Boeing Model 15

Boeing Model 15
Boeing FB-5 at the Steven F. Udvar-Hazy Center
Type:	Double Decker - fighter
Design country:	United States
Manufacturer:	Boeing
First flight:	April 29, 1923
Commissioning:	October 30, 1926
Number of pieces:	155

The Boeing Model 15 (Military designations: PW-9 and FB ) was a single-engine, single-seat biplane - fighter aircraft of the US aircraft manufacturer Boeing .

history

The development of the machine began in 1922 when an attempt was made to produce a type that could keep up with the English and French hunting machines. First of all, the construction of a Fokker D.VII was studied . The fuselage of the Model 15 was made from arc-welded steel tubing. The two wings, made of wood and covered with canvas, were connected to each other by N-shaped struts. At first the machine was to be equipped with a license-built Hispano-Suiza HS 42, but it was decided to use the more powerful Curtiss D-12 . The tunnel-shaped radiator was placed directly below the engine.

The army showed interest in the model and provided in a contract, dated April 4, 1923, for the planned armament and also financed the engine in order to be able to test the machine. The first flight took place on April 29, 1923 and the machine took part in the fighter comparison flight of the US Army in 1923. One of the competitors was the Curtiss PW-8 . This showed that both models are superior to the types currently in use. The Curtiss machine was a little faster, the Boeing Model 15 was a little more agile and robust. Initially, the Curtiss design was preferred, but the arrangement of the radiator and the shape of the wing tapering towards the wing tip of the Boeing machine were to be adopted. According to these specifications, the Curtiss XPW-8B was created, from which the Curtiss P-1 Hawk emerged.

Eventually, however, on September 28, 1923 , the United States Army Air Service bought the machine now known as the Boeing XPW-9 (serial number 23-1216) and ordered two more prototypes that were slightly adapted to Army requirements. The two machines were delivered on May 1, 1924. Two series of 12 (September 19, 1924) and 18 (December 16 of the same year), which were again slightly changed, were then ordered. The first series machines were delivered on October 30, 1926 and taken to their locations in the Philippines and Hawaii .

One machine was equipped with an all-metal wing, the last production machine (serial number 25-324) was equipped for test purposes with a turbo-charged Packard -1A-1500 engine and was given the army designation Boeing XP-4.

On October 26, 1925, another series of 25 machines was ordered, which were equipped with the improved Curtiss D-12C engine and were given the designation Boeing PW-9A. The first delivery took place on June 19, 1926. There was a version of this type called the Boeing Model 68 (Boeing AT-3) with a 180 hp Wright Hispano engine, which, however, disappointed because of underpowering. The last aircraft in this series received a Curtiss D-12D engine and was named Boeing PW-9B. The machines performed well and, after further changes such as the reinforcement of the hull of the PW9B, a change in the fuel system and larger main landing gear wheels, two series of this variant of 15 and 25 copies were ordered. From July 9, 1927, the delivery took place. Again the last machine in this series (serial number 27-202) was used as a prototype for the Boeing PW-9D, with an improved cooler, the original landing gear but improved wheel brakes. An aerodynamically balanced rudder was also used, which was later retrofitted to most PW-9C machines. On August 12, 1927, 12 machines were ordered that were delivered from April 25, 1928. The last machine in this series was equipped with the Curtiss V-1570 engine and was given the new designation Boeing XP-7. There were also versions for the Navy, which were given the designation Boeing FB-1 to FB-5 and, apart from a few pieces of equipment, were identical to the army machines. The last machine in the army was retired in February 1934.

Technical data (PW-9)

Parameter	Data
crew	1
length	7.10 m
span	9.70 m
height	2.40 m
Wing area	24.1 m²
Empty mass	878 kg
Takeoff mass	1414 kg
Top speed	257 km / h
Rate of climb	496 m / min
Service ceiling	18,925 ft (approx. 5,800 m)
Range	390 mi (approx. 630 km)
Engines	a Curtiss D-12 with 435 PS (approx. 320 kW)
Armament	2 forward-firing 7.62 mm machine guns and 110 kg of drop armament

literature

• Gordon Swanborough, Peter M. Bowers : United States Military Aircraft Since 1909. Smithsonian Institution Press, Washington DC 1989, ISBN 0-87474-880-1 .

Web links

Commons : Boeing Model 15  - collection of images, videos and audio files

• Boeing FB-5 Hawk. In: National Air and Space Museum. Smithsonian Institution, accessed October 25, 2019 . 
• The Boeing PW-9 Pursuit Biplane. (PDF) In: Flight, April 3, 1924. Flight, April 3, 1924, accessed on October 26, 2019 (English). 

Individual evidence

1. ↑ PW-9 / FB Fighter. In: History. Boeing, 2019, accessed October 25, 2019 .