Hawker Hurricane Mk IIB.

Hawker Hurricane Mk IIB. 87 Squadron RAF, mid 1941. Flying night defence from Exeter.

Hawker Hurricane

  Hawker Hurricane

The Hawker Hurricane was a British single-seat fighter aircraft designed and predominantly built by Hawker Aircraft Ltd. Some production of the Hurricane was carried out in Canada by the Canada Car and Foundry Co Ltd.

The 1930s design evolved through several versions and adaptations, resulting in a series of aircraft which acted as interceptor-fighters, fighter-bombers (also called "Hurribombers"), and ground support aircraft. Further versions known as the Sea Hurricane had modifications which enabled operation from ships. The Hurricane was significant in enabling the Royal Air Force (RAF) to win the Battle of Britain of 1940, accounting for the majority of the RAF's air victories. About 14,000 Hurricanes were built by the end of 1944 (including about 1,200 converted to Sea Hurricanes, and about 1,400 that were built in Canada), and served in all the major theatres of the Second World War.

The Hurricane was developed by Hawker Aircraft Ltd in response to the Air Ministry specification F.36/34, (modified by F.5/34) for a fighter aircraft built around the new Rolls-Royce engine, then only known as PV-12, later to become famous as the Merlin. At that time, RAF Fighter Command comprised just 13 squadrons, each equipped with either Hawker Furys, Hawker Hart variants, or Bristol Bulldogs – all biplanes with fixed-pitch wooden propellers and non-retractable undercarriages. The design, started in early 1934, was the work of Sidney Camm.

Sydney Camm's original plans submitted in response to the Air Ministry's specification were rejected (apparently "too orthodox," even for the Air Ministry). Camm tore up the proposal and set about designing a fighter as a Hawker company private venture. With economy in mind, the Hurricane was designed using as many of Hawker's existing tools and jigs as possible (the plane was effectively a monoplane version of the successful Hawker Fury); and it was these factors that were major contributors to the plane's success.

Early design stages of the "Fury Monoplane" incorporated a Rolls-Royce Goshawk engine, but this was replaced shortly after with the Merlin, and featured a retractable undercarriage. The design came to be known as the 'Interceptor Monoplane', and by May 1934, the plans had been completed in detail. To test the new design, a one-tenth scale model of the aircraft was made and sent to the National Physical Laboratory at Teddington. A series of wind-tunnel tests confirmed the vital basic aerodynamic qualities of the design were in order, and by December that year, a full-size wooden mock-up of the aircraft had been created.

The first prototype, K5083, began construction in August 1935 incorporating the PV-12 Merlin engine. The completed sections of the aircraft were taken to the Brooklands racing-circuit where Hawkers had an assembly shed, and re-assembled on 23 October 1935. Ground testing and taxi trials took place over the following two weeks, and on 6 November 1935, the prototype took to the air for the first time at the hands of Hawker's chief test pilot, Flight Lieutenant (later Group Captain) P.W.S. Bulman.[3] Flight Lieutenant Bulman was assisted by two other pilots in subsequent flight testing – Philip Lucas flew some of the experimental test flights, while John Hindmarsh conducted the firm's production flight trials.

Even though faster and more advanced than the RAF's current frontline biplane fighters, the Hurricane's design was already outdated when introduced. It employed traditional Hawker construction techniques from previous biplane aircraft, with mechanically fastened, rather than welded joints. It had a Warren girder-type fuselage of high-tensile steel tubes, over which sat frames and longerons that carried the doped linen fabric covering. The Hurricane's traditional construction meant that the airframe was very durable, and proved far more resistant to exploding cannon shells than the metal-skinned Supermarine Spitfire. Initially, the wing structure consisted of two steel spars, and was also fabric-covered. An all-metal, stressed-skin wing of duraluminium (a DERD specification similar to AA2024) was introduced in April 1939 and was used for the all of the later marks. In contrast, the contemporary Spitfire used all-metal monocoque construction and was thus both lighter and stronger, though less tolerant to bullet damage. With its ease of maintenance, widely set landing gear and benign flying characteristics, the Hurricane remained in use in theatres of operations where reliability was more important than performance, long after it was obsolete as a fighter aircraft.

The Hurricane was ordered into production in June 1936, mainly due to its relatively simple construction and ease of manufacture. As the prospect of war was looking more and more likely, and time was of the essence in providing the RAF with an effective fighter aircraft, it was unclear if the much more advanced Spitfire would be able to enter production smoothly, while the Hurricane used well-understood manufacturing techniques. This was true for service squadrons as well, who were experienced in working on and repairing aircraft constructed in a similar fashion to the Hurricane, and the simplicity of its design enabled the improvisation of some remarkable repairs in Squadron workshops.

Powered by a Merlin II engine, the maiden flight of the first production aircraft took place on 12 October 1937. The first four aircraft to enter service with the RAF joined 111 Squadron at RAF Northolt the following December, and by the outbreak of World War II, nearly 500 Hurricanes had been produced, and equipped 18 squadrons.

In all, some 14,000 Hurricanes and Sea Hurricanes were produced. The majority of Hurricanes were built by Hawker (which produced them until 1944) with the Gloster Aircraft Company making most of the rest. The Austin Motor Company built 300. Canada Car and Foundry in Fort William, Ontario, Canada, (where the Chief-Engineer, Elsie MacGill, became known as the "Queen of the Hurricanes") was responsible for production of 1400 Hurricanes, known as the Mk X.

from Wikipedia