Design and development
The Fairey P.4/34 was built to Specification P.4/34 as a light bomber capable of being used as a dive bomber, in competition with the Hawker Henley and an unbuilt Gloster design. Its performance was disappointing and it lost out to the Henley (which was eventually ordered as a target tug).
The Fulmar, a navalised version of the P.4/34 was submitted to meet Specification O.8/38 for a two-crew fleet defence fighter. As it was not expected to encounter fighter opposition, high performance or maneuverability was not considered important but long range and heavy armament were. The provision of a navigator/wireless operator was considered essential for the long, over-ocean flights which would be required.
Looking much like its sister, the Battle, the Fulmar prototype was aerodynamically cleaner and featured a folding wing that was 16 in (41 cm) shorter than its bomber lookalike. The prototype P.4/34 K5099 first flew on 13 January 1937 at Fairey Aviation's Great West Aerodrome with Fairey test pilot Chris Staniland at the controls. After the first flight tests, the tail was revised, being raised 8 in (20 cm).
The first prototype Fulmar acting as "flying mock-up" was powered by a 1,080 hp (810 kW) Rolls Royce Merlin III engine. With this engine, performance was poor, the prototype only reaching 230 mph (370 km/h). With the Merlin VIII engine - a variant unique to the Fulmar and with supercharging optimised for low-level flight - and aerodynamic improvements, speed was improved to 255 mph (410 km/h), which, owing to the desperate need for modern fighters, was considered adequate. As a simple derivative of an existing prototype, the Fulmar promised to be available quickly and an initial order for 127 production aircraft was placed in mid-1938 and the first example flew from Fairey's facility at RAF Ringway near Manchester on 4 January 1940 and the last of 600 Fulmars was delivered from Ringway on 11 December 1942.