The Supermarine Type 324 and Type 325 were

British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories, and Crown Dependencies. ** Britishness, the British identity and common culture * British English, ...

two-engined fighter designs proposed as the replacement for the Supermarine Spitfire and

Hawker Hurricane The Hawker Hurricane is a British single-seat fighter aircraft of the 1930s–40s which was designed and predominantly built by Hawker Aircraft Ltd. for service with the Royal Air Force (RAF). It was overshadowed in the public consciousness b ...

. Neither of them nor a revised design - the Type 327 - to carry cannon was accepted for development and production.

Development

As an aircraft to succeed the Hurricane and Spitfire then entering service,

Air Ministry specification This is a partial list of the British Air Ministry (AM) specifications for aircraft. A specification stemmed from an Operational Requirement, abbreviated "OR", describing what the aircraft would be used for. This in turn led to the specification ...

F.18/37 required a 400+ mph (at 15,000 ft) fighter with twelve .303 inch machine gun armament. Hawker Aircraft submitted a single seat, single engine design with two possible engines, the

Hawker Tornado The Hawker Tornado was a British single-seat fighter aircraft design of the Second World War for the Royal Air Force as a replacement for the Hawker Hurricane. The planned production of Tornados was cancelled after the engine it was designed to ...

Rolls-Royce Vulture The Rolls-Royce Vulture was a British aero engine developed shortly before World War II that was designed and built by Rolls-Royce Limited. The Vulture used the unusual " X-24" configuration, whereby four cylinder blocks derived from the ...

and the

Hawker Typhoon The Hawker Typhoon is a British single-seat fighter-bomber, produced by Hawker Aircraft. It was intended to be a medium-high altitude interceptor, as a replacement for the Hawker Hurricane, but several design problems were encountered and i ...

, with Napier Sabre engine. Gloster submitted two similar twin-boom designs with 12 Browning machine guns in the nose and a pusher Sabre engine as well as an adaptation of their proposal to F.9/37 with nose-mounted armament. Bristol's design was one airframe offered with three alternative engines. In 1938 Supermarine submitted brochures describing the Type 324 (under the company specification No.458) along with the Type 325. Both were compact twin-engine designs - one tractor and one pusher - with either

Rolls-Royce Merlin The Rolls-Royce Merlin is a British liquid-cooled V-12 piston aero engine of 27-litres (1,650 cu in) capacity. Rolls-Royce designed the engine and first ran it in 1933 as a private venture. Initially known as the PV-12, it was late ...

Bristol Taurus The Taurus is a British 14-cylinder two-row radial aircraft engine, produced by the Bristol Engine Company starting in 1936. The Taurus was developed by adding cylinders to the existing single-row Aquila design and transforming it into a twin ...

engines. Hawker's designs - which Sydney Camm had been working on since April 1937 - were accepted and prototypes of each ordered.

Overview

The Type 324 was a low-wing, twin-engined monoplane featuring the elliptical wing shape of the Spitfire, with retractable tricycle undercarriage. Twin engines were expected to give a maximum speed of 450 mph maximum. In addition, the twin layout gave the usual advantages of torque cancellation, improved pilot view, tricycle landing gear, performance, improved take-off performance and allowed the use of the proven Merlin engine. The structure of the aircraft was

Alclad Alclad is a corrosion-resistant aluminium sheet formed from high-purity aluminium surface layers metallurgically bonded (rolled onto) to high-strength aluminium alloy core material. It has a melting point of about 500 degrees celsius, or 932 degree ...

aluminium alloy. The wing was designed in sections, so that alternative engines (Taurus) or armament could be accommodated.

Fowler flap A flap is a high-lift device used to reduce the stalling speed of an aircraft wing at a given weight. Flaps are usually mounted on the wing trailing edges of a fixed-wing aircraft. Flaps are used to reduce the take-off distance and the landi ...

s were fitted for take-off/landing. Spoiler flaps were fitted to improve performance. A number of armament types were considered. The main was 12 Browning in two packs of six in each wing outer section; these could be removed complete with ammunition to allow rapid rearming and servicing of the weapons. When the Air Ministry felt progress on the Westland Whirlwind cannon-armed fighter was too slow, they asked for the F.18/37 tenders to be revised with 20mm cannon armament. Supermarine dropped the pusher design and proposed a six-cannon fighter as the Type 327. The Ministry did not feel its advantages outweighed other considerations, and that the Whirlwind - or the adaption of the Bristol Beaufort - would enter service before Supermarine's design could.

Powerplant

Rolls-Royce Merlin Max speed: 450 mph Cruise speed at 15000 ft: 195 mph

Measurements

Span 41 ft x 40 ft Root Chord 9mm x 9 ft Mean Chord 7.08mm x 7.08 ft Length 31.5 ft x 33.5 ft Height 10.2 ft x 9.75 ft

References

* Buttler, Tony. ''Secret Projects: British Fighters and Bombers 1935-1950 (British Secret Projects 3)''. Leicester, UK: Midland Publishing, 2004. .

External links

{{DEFAULTSORT:Supermarine Type 324 1930s British fighter aircraft Type 324