Hawker Hurricane

Hawker Hurricane Mk IIC - LF363
Hawker Hurricane Mk IIC - LF363
Design and Development

The Hurricane was developed by Hawker 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 the PV-12, later to become famous as the Merlin. At that time, RAF Fighter Command comprised just 13 squadrons, each equipped with either the Hawker Fury, Hawker Hart variant, or Bristol Bulldog – all biplanes with fixed-pitch wooden propellers and non-retractable undercarriages. The design, started in early 1934, was the work of Sydney Camm.

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

Early design stages of the "Fury Monoplane" incorporated a Rolls-Royce Goshawk engine, but this was replaced shortly after by 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 was made and sent to the National Physical Laboratory at Teddington. A series of wind tunnel tests confirmed the 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.

Construction of the first prototype, K5083, began in August 1935 incorporating the PV-12 Merlin engine. The completed sections of the aircraft were taken to Brooklands, where Hawkers had an assembly shed, and re-assembled on 23rd October 1935. Ground testing and taxi trials took place over the following two weeks, and on 6th 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. 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.

Though faster and more advanced than the RAF's current front line 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 covering. An advantage conferred by the steel-tube structure was that cannon shells could pass right through the wood and fabric covering without exploding. Even if one of the steel tubes were damaged the repair work required was relatively simple and could be done by the ground crew at the airfield. An all metal structure, as with the Spitfire, damaged by an exploding cannon shell required more specialised equipment to repair. The old-fashioned structure also permitted the assembly of Hurricanes with relatively basic equipment under field conditions. Crated Hurricanes were assembled in West Africa and flown across the Sahara to the Middle East theatre, and to save space, some Royal Navy aircraft carriers carried their reserve Sea Hurricanes dismantled into their major assemblies, which were slung up on the hangar bulkheads and deckhead for reassembly when needed.

Initially, the wing structure consisted of two steel spars, and was also fabric-covered. Several fabric-wing Hurricanes were still in service during the Battle of Britain, although a good number had had their wings replaced during servicing or after repair. Changing the wings only required three hours' work per aircraft. An all-metal, stressed-skin wing of duraluminium (a DERD specification similar to AA2024) was introduced in April 1939 and was used for all of the later marks. The metal skinned wings allowed a diving speed that was 80mph (129 km/h) higher than the fabric-covered ones. They were very different in construction but were interchangeable with the fabric-covered wings, and one trials Hurricane, L1877, was even flown with a fabric-covered port wing and metal-covered starboard wing. The great advantage of the metal-covered wings over the fabric ones was that the metal ones could carry far greater stress loads without needing so much structure beneath.

One of Camm's priorities with the new fighter was to provide the pilot with good all round visibility. To this end the cockpit was mounted reasonably high in the fuselage, creating a distinctive "hump-backed" silhouette. Pilot access to the cockpit was aided by a retractable stirrup mounted below the trailing edge of the port wing. This was linked to a spring-loaded hinged flap which covered a handhold on the fuselage, just behind the cockpit. When the flap was shut the footstep retracted into the fuselage. In addition, both wingroots were coated with strips of non-slip material. 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, easy handling and a stable gun platform were more important than performance, typically in roles like ground attack. One of the design requirements of the original specification was that the Hurricane, as well as the Spitfire, was also to be used as a night-fighter. The Hurricane proved to be a relatively simple aircraft to fly at night and was to be instrumental in shooting down several German aircraft during the nocturnal hours. From early 1941 the Hurricane would also be used as an "intruder" aircraft, patrolling German airfields in France at night in an attempt to catch night bombers during takeoffs or landings.

The last Hurricane ever built, of 14,533. A Mk IIC version, originally known as "The Last of the Many" and owned by Hawker, this aircraft is now flown by the Battle of Britain Memorial Flight.

The Hurricane was ordered into production in June 1936, mainly due to its relatively simple construction and ease of manufacture. As war was looking increasingly likely, and time was of the essence in providing the RAF with an effective fighter aircraft, it was unclear if the 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 whose construction employed the same principles as the Hurricane, and the simplicity of its design enabled the improvisation of some remarkable repairs in Squadron workshops.

The maiden flight of the first production aircraft, powered by a Merlin II engine, took place on 12th October 1937. The first four aircraft to enter service with the RAF joined No.111 Squadron RAF at RAF Northolt the following December. By the outbreak of the Second World War, nearly 500 Hurricanes had been produced, and had equipped 18 squadrons. During 1940, Lord Beaverbrook, who was the Minister of Aircraft Production, established an organisation in which a number of manufacturers were seconded to repair and overhaul battle damaged Hurricanes. The Civilian Repair Organisation also overhauled battle-weary aircraft, which were later sent to training units or to other air forces, one of the factories involved was the Austin Aero Company's Cofton Hackett plant, which also built 300 Hurricanes. Another was David Rosenfield Ltd, based at Barton aerodrome near Manchester.

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 Hawker's sister company, the Gloster Aircraft Company, making (2750) most of the rest. Austin Aero Ltd 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. In 1939, production of 100 Hurricanes was initiated in Yugoslavia by Zmaj and Rogozarski. Of these, 20 were built by Zmaj by April 1941. One of these was fitted with a DB 601 and test flown in 1941. A contract for 80 Hurricanes was placed with Fairey's Belgian subsidiary Avions Fairey SA for the Belgian Air Force in 1938. Three were built and two flown by the time of the Blitzkrieg in May 1940.

Operational History

In response to a request from the French government for 10 fighter squadrons to provide air support, Air Chief Marshal Sir Hugh Dowding, Commander-in-Chief of RAF Fighter Command, insisted that this number would deplete British defence's severely, and so initially only four squadrons of Hurricanes, Nos.1, 73, 85 and 87, were relocated to France, keeping Spitfires back for Home defence. The first to arrive was No.73 Squadron on 10th September 1939, followed shortly by the other three. A little later, No.607 and No.615 Squadrons joined them.

In May the following year, Nos.3, 79 and 504 Squadrons reinforced the earlier units as Germany's Blitzkrieg gathered momentum, and on 13th May 1940, a further 32 Hurricanes arrived. All 10 requested Hurricane squadrons were then operating from French soil and felt the full force of the Nazi offensive. By 17th May, the end of the first week of fighting, only three of the squadrons were near operational strength, but despite their heavy losses the Hurricanes had managed to destroy nearly double the number of German aircraft.

On 27th May 1940, 13 aircraft from No.501 Squadron intercepted 24 Heinkel He 111s escorted by 20 Messerschmitt Bf 110s, and during the ensuing battle, 11 Heinkel's were claimed as "kills" and others damaged, with little damage to the Hurricanes. Initial engagements with the Luftwaffe showed the Hurricane to be a tight-turning and steady platform, but the Watts two-bladed propeller was clearly unsuitable. At least one pilot complained of how a Heinkel 111 was able to pull away from him in a chase, yet by this time the Heinkel was obsolescent.

At the end of June 1940, following the fall of France, the majority of the RAF's 36 fighter squadrons were equipped with Hurricanes. The Battle of Britain officially lasted from 10th July until 31st October 1940, but the heaviest fighting took place between 8th August and 21st September. Both the Supermarine Spitfire and the Hurricane are renowned for their part in defending Britain against the Luftwaffe, generally the Spitfire would intercept the German fighters, leaving Hurricanes to concentrate on the bombers, but despite the undoubted abilities of the thoroughbred Spitfire, it was the workhorse Hurricane that scored the highest number of RAF victories during this period, accounting for 1593 of the 2739 claimed.

One lesson learned in combat had been that even eight .303 machine guns would not guarantee a successful kill in the fast-moving air combats that were taking place. In spite of this, during the month from 10th July to 11th August, for example, RAF fighters fired at 114 German bombers and shot down 80, a destruction ratio of 70%. Against the Bf 109, the RAF fighters attacked 70 and shot down 54 of these, a ratio of 77%. Part of the success of the British fighters was possibly due to the use of the de Wilde incendiary round.

The only Battle of Britain Victoria Cross, and the only VC awarded to a member of Fighter Command during the war, was awarded to Flight Lieutenant Eric Nicholson of No. 249 Squadron as a result of an action on 16th August 1940 when his section of three Hurricanes was bounced from above by Bf 110 fighters. All three were hit simultaneously. Nicholson was badly wounded, and his Hurricane was damaged and engulfed in flames. While attempting to leave the cockpit, Nicholson noticed that one of the Bf 110s had overshot his aircraft. He returned to the cockpit, which by now was a blazing inferno, engaged the enemy, and may have shot the Bf 110 down. Following the Battle of Britain, the Hurricane continued to give service, and through the Blitz of 1941, was the principal single-seat night fighter.

The Hurricane Mk II was hastily tropicalised following Italy's entry into the war in June 1940. These aircraft were initially ferried through France by air to No.80 Squadron in Egypt to replace Gladiators. The Hurricane claimed its first kill in the Mediterranean on 19th June 1940, when F/O P.G. Wykeham-Barnes reported shooting down two Fiat CR.42s.

Hurricanes served with several British Commonwealth squadrons in the Desert Air Force. They suffered heavy losses over North Africa after the arrival of Bf 109E and F-variants and were progressively replaced in the air superiority role from June 1941. However, fighter-bomber variants (Hurribombers) retained an edge in the ground attack role, due to their impressive armament. During and following the five-day El Alamein artillery barrage that commenced on the night of 23rd October 1942, six squadrons of Hurricanes claimed to have destroyed 39 tanks, 212 lorries and armoured troop-carriers, 26 bowsers, 42 guns, 200 various other vehicles and four small fuel and ammunition dumps, flying 842 sorties with the loss of 11 pilots. Whilst performing in a ground support role, Hurricanes based at RAF Castel Benito, Tripoli, knocked out six tanks, 13 armoured vehicles, ten lorries, five half-tracks, a gun and trailer, and a wireless van on 10th March 1943, with no losses to themselves.

The Hurricane played a significant role in the defence of Malta. When Italy entered the war on 10th June 1940, Malta's air defence rested on Gloster Gladiators which managed to hold out against vastly superior numbers of the Italian air force during the following three weeks. Four Hurricanes joined them at the end of June, and together they faced attacks throughout July from the 200 enemy aircraft based in Sicily, with the loss of one Gladiator and one Hurricane. Further reinforcements arrived on 2nd August in the form of 12 more Hurricanes and two Blackburn Skuas. The increasing number of British aircraft on the island, at last, prompted the Italians to employ German Junkers Ju 87 dive bombers to try and destroy the airfields. Finally, in an attempt to overcome the stiff resistance put up by these few aircraft, the Luftwaffe took up base on the Sicilian airfields, only to find that Malta was not an easy target. After numerous attacks on the island over the following months, and the arrival of an extra 23 Hurricanes at the end of April 1941, and a further delivery a month later.

Production Summary
Mk I3774
Mk IIA1906 (all Mk I conversions)
Mk IIB3100
Mk IIC3400
Mk IID800
Mk IIE250
Mk IV794
Mk V2 (both Mk IV conversions)
Mk X490 (Canadian built variant)
Mk XI150 (Canadian built variant)
Mk II400 (Canadian built variant)
Mk IIA50 (Canadian built variant)
Sea Hurricane Mk IA50 (all Mk I conversions)
Sea Hurricane Mk IB300 (all Mk IIA conversions)
Sea Hurricane Mk IC400 (all Mk IIB & C conversions)
Sea Hurricane Mk IIC400 (all Mk IIC conversions)
Sea Hurricane Mk XIIA? Mk XIIA conversions
PR.II28 (all Mk I conversions)
Specifications(Hurricane Mk I)
Length:31.40ft (9.57m)
Width:39.99ft (12.19m)
Height:13.12ft (4.00m)
Empty Weight:4,982lbs (2,260kg)
MTOW:6,446lbs (2,924kg)
Max Speed:318mph (511kmh 276kts)
Max Range:460miles (740km)
Rate-of-Climb:2,520ft/min (768m/min)
Service Ceiling:35,991ft (10,970m 6.8miles)
Engine:1 x Rolls-Royce Merlin III 12-cylinder liguid-cooled engine generating 1,030hp
Armament Standard:8 x 7.7mm machine guns
Armament Optional:2 x 500lb bombs or 6 x air-to-surface rockets