Role Patrol flying boat
National origin United States
Manufacturer Boeing
First flight 1925
Primary user United States Navy
Number built 1

The Boeing XPB (company Model 50) was an American twin-engined biplane long-range patrol flying boat of the 1920s. A single example was built for the United States Navy.

Design and development

In September 1924, the Naval Aircraft Factory was tasked with designing a long-range twin-engined flying boat, capable of flying the 2,400 mi (3,860 km) between San Francisco and Hawaii. The initial design was carried out by Isaac Laddon, an employee of Consolidated Aircraft, and then passed to Boeing for detailed design and construction. The new flying boat, the Boeing Model 50, was a two-bay biplane of very streamlined design for flying boats of the time. The wings were of metal construction, with wooden wingtips and leading edges. The fuselage had a metal lower part, with the upper half made of laminated wooden frames with a wood veneer covering. Two 800 hp (600 kW) Packard 2A-2500 V12 engines driving four-bladed propellers were mounted in tandem between the wings above the fuselage.[1]

Operational history

Boeing XPB-1
Boeing XPB-1

The Boeing Model 50, designated XPB-1 by the US Navy, made its maiden flight in August 1925.[2] It was intended to use it to lead a pair of Naval Aircraft Factory PN-9s in an attempt to fly to Hawaii on 31 August 1925, but engine trouble led to its participation in the flight being cancelled.[3][4] In 1928, the aircraft was modified by the Naval Aircraft Factory, its Packard engines were replaced by two 500 hp (370 kW) geared Pratt & Whitney R-1690 Hornet radial engines, leading to the new designation XPB-2.

Specifications (XPB-1)

Data from Boeing Aircraft since 1916[5]

General characteristics



See also

Related lists


  1. ^ a b Bowers 1989, p. 73.
  2. ^ Yenne 2005, p. 15.
  3. ^ "Boeing C to Z, and hyphenates". Aerofiles. Retrieved 18 June 2010.
  4. ^ "San Francisco-Honolulu Flight Fails". Flight, 10 September 1925, p. 579.
  5. ^ Bowers 1989, p. 75.
  • Bowers, Peter M. Boeing Aircraft since 1916. London:Putnam, 1989. ISBN 0-85177-804-6.
  • Yenne, Bill. The Story of the Boeing Company. St Paul, USA: Zenith Imprint, 2005. ISBN 0-7603-2333-X.