Boulton Paul Bittern

P.31 Bittern
Role
Manufacturer	Boulton Paul Limited
First flight	February 1927
Number built	2

The Boulton Paul Bittern was a 1920s British night-fighter aircraft from Boulton Paul Limited of Norwich, named after the marsh bird of the same name

Design and development

Designed to Air Ministry Specification 27/24, which called for a single-seat night fighter for use against enemy bomber aircraft, the Bittern design was different from others in that it was a twin-engined shoulder wing monoplane rather than the usual single-engine biplane.

Two prototypes were built, both very underpowered. As a result, during testing performance was so poor that further development was abandoned.^[1]

The first prototype had fixed .303 in (7.7 mm) Vickers machine guns, the second had guns that could be angled from 0-45° upwards so the fighter could attack bombers from below without having to put the aircraft into a climb. The wingspan of the second prototype was increased by about 5 ft (1.5 m).^[2][3]

Specifications (Second prototype)

Data from The British Fighter since 1912 ^[4]

General characteristics

• Crew: 1 (pilot)
• Length: 32 ft 4 in (9.86 m)
• Wingspan: 41 ft 0 in (12.50 m)
• Height: ()
• Empty weight: 3,215 lb (1,461 kg)
• Loaded weight: 4,500 lb (2,045 kg)
• Powerplant: 2 × Armstrong Siddeley Lynx seven cylinder air-cooled radial engine, 230 hp (172 kW) each

Performance

• Maximum speed: 145 mph (126 kn, 233 km/h)
• Endurance: 3¾ hr

Armament

• Guns: 2 × 0.303 in (7.7 mm) Lewis guns mounted in barbettes

See also

Related lists

• List of fighter aircraft
  

References

Notes

1. ^ Donald, David, ed (1997). The Encyclopedia of World Aircraft. Prospero Books. pp. pg 118. ISBN 1-85605-375-X. 
2. ^ Boulton-Paul P.31 Bittern - night fighter
3. ^ The WWII Fighter Gun Debate: Upward firing guns
4. ^ Mason 1992, p.187.

Bibliography

• Mason, Francis K. (1992). The British Fighter since 1912. Annapolis, Maryland, US: Naval Institute Press. ISBN 1-55750-082-7.