The Boulton & Paul P.33 Partridge was a single seat single-engine biplane fighter designed to an Air Ministry specification.
The Partridge first flew in early in 1928 and appeared at the Hendon RAF display that July.
Competitive trials between the contestants for F.9/26 began in January at RAF Martlesham Heath.
The Hawker Hawfinch and the eventual winner, the Bristol Bulldog stood out from the others in terms of handling.
These two and the Partridge had similar performance figures, with the Bulldog 7 mph (11 km/h) faster than the Partridge but having a lower service ceiling.
The major failure of the Partridge was its poor longitudinal stability and control, which led to heavy stick forces and made aerobatics difficult.
No further orders were placed.
Some modifications were made to the original machine during the trials, notably an enlarged cockpit to assist a pilot who was baling out, and this variation became known as the Mk II.
Boulton & Paul had always intended the Partridge to be powered by the new but unavailable Bristol Mercury and the designation Mk III was reserved for this unbuilt version.
Specifications
Crew
1
Length
23 ft 1 in (7.04 m)
Upper wingspan
35 ft 0 in (10.67 m)
Lower wingspan
31 ft 0 in (9.45 m)
Height
11 ft 0 in (3.35 m)
Wing area
311 sq ft (28.9 m2)
Empty weight
2,021 lb (917 kg)
Gross weight
3,097 lb (1,405 kg)
Powerplant
1 × Bristol Jupiter VII 9-cylinder air cooled radial engine, 440 hp (330 kW)
Performance
Maximum speed
167 mph (269 km/h, 145 kn) at 10,000 ft (3,000 m)
Service ceiling
28,950 ft (8,820 m)
Time to altitude
6 min 30 s to 10,000 ft (3,000 m)
Armament
Guns
2 × 0.303 (7.7 mm) nose mounted Vickers machine guns.