Background

During the early 1930s, when Hawker Aircraft company developed the Hurricane, RAF Fighter Command had just 13 squadrons, equipped with the Hawker Fury, Hawker Demon, or the Bristol Bulldog, all biplanes with fixed-pitch wooden propellers and non-retractable undercarriages.^[1][2] At the time, there was an institutional reluctance towards change within the Air Staff; some senior figures were prejudiced against the adoption of monoplane fighter aircraft, while mid-level officers were typically more open-minded.^[2]

In 1934 the British Air Ministry issued Specification F.5/34 in response to demands within the Royal Air Force (RAF) for a new generation of fighter aircraft. Earlier, during 1933, British aircraft designer Sydney Camm had conducted discussions with Major John Buchanan of the Directorate of Technical Development on a monoplane based on the existing Fury.^[3] Mason attributes Camm's discussions with figures within the RAF, such as Squadron Leader Ralph Sorley, as having provoked the specification and some of its details, such as the preference for armaments being installed within the wings instead of within the aircraft's nose.^[4]

An outline of the "Fury Monoplane" armed with two guns in the wings and two in the nose and powered by the Goshawk engine was prepared and discussed with Roger Liptrot of the Air Ministry in December 1933.^[5] The design was reworked with the PV.12, following detailed work working drawings of the "Interceptor Monoplane" were begun in May 1934. The complete design was presented to the Air Ministry on 4 September.^[6]

Camm's initial submission in response to the earlier fighter specification F.7/30 was a development of the Fury, the Hawker P.V.3, ^{[N 1][7]} However, the P.V.3 was not among the proposals which the Air Ministry selected to be built as prototype to official contract.^{[N 2]} After the rejection of the P.V.3 proposal, Camm started work on a new design involving a cantilever monoplane arrangement with a fixed undercarriage, armed with four machine guns and powered by the Rolls-Royce Goshawk engine. The original 1934 armament specifications for what evolved into the Hurricane were for a similar armament fitment to the Gloster Gladiator: four machine guns; two in the wings and two in the fuselage, synchronised to fire through the propeller arc. By January 1934, the proposal's detail drawings had been finished, but these failed to impress the Air Ministry enough for a prototype to be ordered.^[8]

Camm's response to this rejection was to further develop the design, introducing a retractable undercarriage and replacing the unsatisfactory Goshawk engine with a new Rolls-Royce design, initially designated the PV-12, which went on to become famous as the Merlin. In August 1934, a one-tenth scale model of the design was produced and sent to the National Physical Laboratory at Teddington, where a series of wind tunnel tests confirmed the aerodynamics were satisfactory, and in September 1934 Camm again approached the Air Ministry. This time, the Ministry's response was favourable, and a prototype of the "Interceptor Monoplane" was promptly ordered.^[9]

In July 1934, at a meeting chaired by Air Commodore Arthur Tedder (director of training), the Air Ministry Science Officer Captain F.W. "Gunner" Hill presented his calculation showing that future fighters must carry no fewer than eight machine guns, each capable of firing 1,000 rounds per minute.^[10]/ Hill's assistant in making his calculations was his 13-year-old daughter Hazel Hill. Of the decision to place eight machine guns in fighters, Claude Hilton Keith, at the time assistant director of armament research and development, said "The battle was brisk and was carried into very high quarters before the implementing authority was given. My Branch had made out a sound case for 8-gun fighters and if this recommendation had not been accepted and we had been content with half-measures, it might indeed have gone ill for us during the late summer of 1940". Present at the meeting was Squadron Leader Ralph Sorley of the Air Ministry's Operational Requirements branch, who played an important role in the decision. In November 1934, the Air Ministry issued Specification F.5/34 which called for new fighter aircraft to be armed with a total of eight guns. However, by this time, work had progressed too far to immediately modify the planned four-gun installation. By January 1935, a wooden mock-up had been finished, and although a number of suggestions for detail changes were made, construction of the prototype was approved, and a new specification (F.36/34) was written around the design. In July 1935, this specification was amended to include installation of eight guns.^[4][11]

The mock-up conference with Air Ministry staff was on 10 January 1935 at Kingston. The ministry order to purchase a prototype to the September proposal was placed on 21 February 1935. At the time the armament was two Vickers Mark V machine guns in the fuselage and one Browning machine gun in each wing. Work on stressed skin outer wings to replace the fabric covered ones began in July and the contract was altered in August to include another set of wings with eight guns in them; the guns were to be either Vickers or Brownings.^[6] These wings were delivered in June 1936.^[6]

Prototype and trials

An early mock-up for the Hurricane's fuselage, showing side fuselage-mounted synchronised machine gun, like earlier British biplane fighters.

By the end of August 1935, work on the airframe had been completed at Hawker's Kingston upon Thames facility and the aircraft components were transported to Brooklands, Surrey, where Hawker had an assembly shed; the prototype was fully re-assembled on 23 October 1935.^[4] Ground testing and taxi trials took place over the following two weeks. On 6 November 1935 the prototype K5083 took to the air for the first time at the hands of Hawker's chief test pilot, Flight Lieutenant George Bulman.^[12] 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.^[13] As completed, the prototype had been fitted with ballast to represent the aircraft's armament prior to the acceptance of the final multi-gun wing armament.^[14]

By March 1936, the prototype had completed ten flying hours, covering all major portions of the flight envelope. Early testing had gone reasonably well, especially in light of the trial status of the Merlin engine, which had yet to achieve full flight certification at this time and thus severe restrictions had been imposed upon use of the engine.^[4] In early 1936, the prototype was transferred to RAF Martlesham Heath, Suffolk, to participate in initial service trials under the direction of Squadron Leader D.F. Anderson. Sammy Wroath, later to be the founding commandant of the Empire Test Pilots' School, was the RAF test pilot for the Hurricane: his report was favourable, stating that: "The aircraft is simple and easy to fly and has no apparent vices" and proceeded to praise its control response.^[15]

K5083, the prototype, photographed before its first flight in November 1935

In the course of RAF trials, despite the problems with the Merlin engine, which had suffered numerous failures and necessitating several changes, enthusiastic reports were produced on the aircraft and its performance. The trials had proved the aircraft to possess a maximum level speed of 315 mph (507 km/h) at an altitude of 16,200 ft (4,900 m), climb to 15,000 ft (4,600 m) in 5.7 minutes, and a stalling speed of 57 mph (92 km/h) (only marginally higher than the Gladiator biplane), the last achieved using its flaps.^[4]

In the course of further testing, it was found that the Hurricane had poor spin recovery characteristics, in which all rudder authority could be lost due to shielding of the rudder.^[16] Hawker's response to the issue was to request that spinning tests be waived, but the Air Ministry refused the request;^[17] the situation was resolved by the Royal Aircraft Establishment (RAE), who established that the aerodynamic problem had been caused by a breakdown of the airflow over the lower fuselage, and could be cured by the addition of a small ventral fairing and extension of the bottom of the rudder. This discovery had come too late for the changes to be incorporated in the first production aircraft, but were introduced upon the 61st built and all subsequent aircraft.^[18]

In early 1936, the Hawker board of directors had decided, in the absence of official authorisation and at company expense, to proceed with the issue of the design drawings to the production design office and to start tooling-up for a production line capable of producing a batch of 1,000 Hurricanes.^[19][20]

Production

Hurricane production line, 1942

In June 1936 the Air Ministry placed its first order for 600 aircraft.^[16] On 26 June 1936 the Air Ministry approved the type name of "Hurricane" that had been proposed by Hawker, and an informal naming ceremony occurred the following month during an official visit by King Edward VIII to Martlesham Heath.^[16][21]

It was significantly cheaper than Supermarine Spitfire and took 10,300 man hours per airframe to produce, compared to 15,200 for the Spitfire, which had many parts formed by hand, with English wheels.^[22] As war was looking likely, and time was of the essence in providing the RAF with an effective fighter, the authorities expected there to be problems with the more advanced Spitfire, while the Hurricane made use of well-proven manufacturing techniques.^[22] The service squadrons were also already experienced in maintaining aircraft structurally similar to the Hurricane.^[22] A fabric-covered wing was initially adopted in order to accelerate production, while a higher-performing stressed-skin metal wing was introduced in late 1939.^[16]

The first production Hurricane I first flew on 12 October 1937, flown by Flight Lieutenant Philip Lucas and powered by a Merlin II engine. While a contract for 600 Hurricanes was received on 2 June 1936, deliveries lagged by roughly six months due to a decision in December 1936 to replace the Merlin I with the improved Merlin II, which resulted in many detail alterations.

Trainee aircraft fitters working on instructional Hurricanes 1939–1940

Merlin I production ended after 180 were built. This engine had been prioritised for the Fairey Battle light bomber and the Hawker Henley, a failed competitor to the Battle briefly adapted as a target tug which shared common elements with the Hurricane design.^[16] By the following December, the first four aircraft to enter service with the RAF had joined No. 111 Squadron, stationed at RAF Northolt. By February 1938, No. 111 Squadron had received 16 Hurricanes.^[16] Upon the outbreak of the Second World War, over 550 Hurricanes had been produced equipping 18 squadrons, with 3,500 more on order.^[23][24]

During 1940, Lord Beaverbrook, the Minister of Aircraft Production, established the Civilian Repair Organisation through which a number of manufacturers were to repair and overhaul battle-damaged aircraft including Hurricanes. Some of these were later sent to training units or to other air forces. Factories involved included the Austin Aero Company's Cofton Hackett plant and David Rosenfield Ltd, based at Barton aerodrome near Manchester.

The Canadian Car and Foundry of Fort William, Ontario, Canada was a major Hurricane manufacturer, producing them from November 1938 after receiving their initial contract for 40 Hurricanes. The facility's chief engineer, Elsie MacGill, became known as the "Queen of the Hurricanes".^[24] The initiative was commercially driven, but was endorsed by the British government. Hawker recognised that a major conflict was inevitable after the Munich Crisis of 1938 and drew up preliminary plans to expand Hurricane production at a new factory in Canada. Under this plan, samples, pattern aircraft, and design documents stored on microfilm were shipped to Canada. In 1938/39 the RCAF ordered 24 Hurricanes to equip one fighter squadron, 20 of which were delivered, and two were supplied to Canadian Car and Foundry as pattern aircraft but one probably did not arrive, while the other was returned to Britain in 1940. The first Hurricane built at Canadian Car and Foundry was completed in February 1940.^[24] Canadian-built Hurricanes shipped to Britain participated the Battle of Britain.^[24]

Overall, some 14,487 Hurricanes and Sea Hurricanes were produced in England and Canada.^[25] The majority of Hurricanes, 9,986 were built by Hawker (who produced the type at Brooklands from December 1937 to October 1942 and Langley from October 1939 to July 1944), while Hawker's sister company, the Gloster Aircraft Company, constructed 2,750. The Austin Aero Company completed 300 Hurricanes. Canada Car and Foundry produced 1,451 Hurricanes.^[26] However those shipped to Britain were often incomplete airframes and about 80% were delivered without an engine.

In 1939, production of 100 Hurricanes was initiated in Yugoslavia by Zmaj and Rogožarski.^[27] Of these, 20 were built by Zmaj by April 1941. Recognising that the supply of British-made Merlin engines might not be guaranteed, it was decided to fit one of the Yugoslavian Hurricanes with a Daimler-Benz DB 601 engine instead. This aircraft was flown in 1941.^[24] In 1938, a contract for 80 Hurricanes was placed with Fairey's Belgian subsidiary Avions Fairey SA for the Belgian Air Force, and it was intended to arm these aircraft with four 13.2 mm (0.52 in) Browning machine guns. Three were built and two flown with this armament by the time of the German invasion of Belgium in May 1940, with at least 12 more constructed by Avions Fairey armed with the conventional eight rifle calibre machine gun armament.^[24][28]

Pre-war

Yugoslavian Hurricane Mk. IV

By the middle of 1938, the first 50 Hurricanes had reached squadrons and, at that time, it had been assessed that the rate of production was slightly greater than the RAF's capacity to introduce the new aircraft, which had already been accelerated.^[45] Accordingly, the British government gave Hawker the clearance to sell excess aircraft to nations that were likely to oppose German expansion. As a result, there were some modest export sales made to other countries; at the earliest opportunity, a former RAF Hurricane I was dispatched to Yugoslavia for evaluation purposes.^[45] Shortly after this evaluation, an order for 24 Hurricane Mk.Is for the Royal Yugoslav Air Force was received; this was followed by the purchase of a production licence for the Hurricane by Yugoslavia.^[27] Yugoslavian Hurricanes saw action against the Luftwaffe during the invasion of Yugoslavia in 1941 by the Axis powers.^[24]

To the end of August 1939, 14 Hurricanes had been sent to Poland (SS Lassel left Liverpool on 30 August 1939 heading to Constanza in Romania, these planes never reached Poland and ultimately were sold to Turkey^[46]), seven ex-RAF Hurricanes had been sent to South Africa, while another 13 ex-RAF Hurricanes were sent to Turkey, 13 Hurricanes had been built for Belgium, 21 for Canada including one as a pattern for Canadian Car and Foundry, one for Iran, one for Poland, three for Romania and 12 for Yugoslavia. All the built for export aircraft were taken from the RAF order and so all originally had an RAF serial. Further exports were done in the final four months of 1939 and early 1940.

Hurricane production was increased as part of a plan to create a reserve of attrition aircraft as well as re-equip existing squadrons and newly formed ones such as those of the Auxiliary Air Force. Expansion scheme E included a target of 500 fighters of all types by the start of 1938. By the time of the Munich Crisis, there were only two fully operational RAF squadrons of the planned 12 to be equipped with Hurricanes.^[47] By the time of the German invasion of Poland there were 16 operational Hurricane squadrons as well as a further two more that were in the process of converting.^[48]

Phoney War

Personnel of 85 Squadron next to a Hurricane I, Lille, Seclin, France, on 10 May 1940

Owing to the Hurricane's rugged construction, ease of maintenance and repair in the field, and its docile landing and take-off characteristics, coupled with a wide-track undercarriage, it was selected to go to France as the principal RAF fighter. Two Hurricane squadrons, No. 1 and No. 73, formed 67 Wing of the Advanced Air Striking Force, while two more, No. 85 and No. 87, formed 60 Wing of the Air Component, BEF.

While the two squadrons of No. 60 Wing had their Hurricanes painted in the standard colour scheme and markings of Home-based fighters, those of No. 67 Wing differed considerably. It was probably because No. 1 and No. 73 Squadrons were operating in close proximity to French fighter squadrons that these units painted red, white, and blue stripes over the entire height of the rudders on their Hurricanes in a similar manner to the standard French AF National markings.

As the French squadrons were not familiar with the British use of code letters, and there could have been cause for error in aircraft identification, both Hurricane squadrons removed their squadron identification letters, leaving the grey-painted aircraft letter aft of the fuselage roundel. The decision to adopt these special changes in markings seems to have been made at 67 Group HQ (the immediate command authority for the two squadrons involved) to suit local circumstances.^[49]

On 24 August 1939, the British government gave orders partially to mobilise and No. 1 Group RAF (Air Vice-Marshal Patrick Playfair) sent its 10 Fairey Battle day-bomber squadrons to France, according to plans established by the British and French earlier in the year. The group was the first echelon of the RAF Advanced Air Striking Force (AASF) and flew from bases at Abingdon, Harwell, Benson, Boscombe Down and Bicester. The group HQ became the AASF when the order to move to France was received and the home station HQs, 71, 72 74–76 Wings. As part of the AASF, No. 1 and No. 73 Squadrons Fighter Command operating Hawker Hurricanes were also sent to France (No. 1 to Berry-au-Bac, north-west of Paris; No. 73 to Rouvres) and assigned escort duties independent of the Air Component BEF.

The Hurricane had its first combat action on 21 October 1939, at the start of the Phoney War. That day, "A" Flight of 46 Squadron took off from North Coates satellite airfield, on the Lincolnshire coast, and was directed to intercept a formation of nine Heinkel He 115B floatplanes from 1/KüFlGr 906, searching for ships to attack in the North Sea. The Heinkels, which were flying at sea level in an attempt to avoid fighter attacks, had already been attacked and damaged by two Spitfires from 72 Squadron when six Hurricanes intercepted them. The Hurricanes shot down four of the enemy in rapid succession, 46 Squadron claiming five and the Spitfire pilots two.^[50]

In response to a request from the French government for the provision of 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 defences severely, and so initially only four squadrons of Hurricanes, 1, 73, 85 and 87, were relocated to France, keeping Spitfires back for "Home" defence.^[51] The first to arrive was 73 Squadron on 10 September 1939, followed shortly by the other three. A little later, 607 and 615 Squadrons joined them.^[52]

After his first flight in October 1939, Hurricane pilot Roland Beamont subsequently flew operationally with 87 Squadron, claiming three enemy aircraft during the French campaign, and delivered great praise for his aircraft's performance:

Throughout the bad days of 1940, 87 Squadron had maintained a proficient formation aerobatic team, the precise flying controls and responsive engines permitting precision formation through loops, barrel rolls, 1 g semi-stall turns and rolls off half-loops ... My Hurricane was never hit in the Battles of France and Britain, and in over 700 hr on type I never experienced an engine failure.

— Roland Beamont, summarising his wartime experience as a pilot.^[53]

Hurricane Mk.I of the 46 Squadron during the Norwegian campaign, May 1940. This aircraft was abandoned in Norway.

While the opening months of the war were characterised by little air activity in general, there were sporadic engagements and aerial skirmishes between the two sides.^[52] On 30 October 1939 Hurricanes saw action over France. That day, Pilot Officer P. W. O. "Boy" Mould of 1 Squadron, flying Hurricane L1842, shot down a Dornier Do 17P from 2(F)/123. The German aircraft, sent to photograph Allied airfields close to the border, fell in flames about 10 mi (16 km) west of Toul. Mould was the first RAF pilot to down an enemy aircraft on the European continent in the Second World War.^[54] According to Mason, the experiences gained in these early engagements proved invaluable in developing tactics which became tried and tested, and rapidly spread throughout Fighter Command.^[52]

On 6 November 1939, Pilot Officer Peter Ayerst from 73 Squadron was the first to clash with a Messerschmitt Bf 109. After the dogfight, he came back with five holes in his fuselage.^[55] Flying Officer Cobber Kain, a New Zealander, was responsible for 73 Squadron's first victory, on 8 November 1939 while stationed at Rouvres.^[56] He went on to become one of the RAF's first fighter aces of the war, being credited with 16 kills. On 22 December, the Hurricanes in France suffered their first losses: three, while trying to intercept an unidentified aircraft between Metz and Thionville, were jumped by four Bf 109Es from III./JG 53, with their Gruppenkommandeur, Spanish Civil War ace Captain Werner Mölders, in the lead. Mölders and Leutnant Hans von Hahn shot down the Hurricanes of Sergeant R. M. Perry and J. Winn for no loss.^[55]

Battle of France

Hurricane I of 1 Squadron being refuelled at Vassincourt, France

In May 1940, Nos. 3, 79 and 504 Squadrons reinforced the earlier units as Germany's Blitzkrieg gathered momentum. On 10 May, the first day of the Battle of France, Flight Lieutenant R. E. Lovett and Flying Officer "Fanny" Orton, of 73 Squadron, were the first RAF pilots to engage enemy aircraft in the campaign. They attacked one of three Dornier Do 17s from 4. Staffel/KG 2 that were flying over their airfield at Rouvres-en-Woevre. The Dornier went away unscathed, while Orton was hit by defensive fire and had to force land.^[57] On the same day the Hurricane squadrons claimed 42 German aircraft, none of them fighters, shot down during 208 sorties; seven Hurricanes were lost but no pilots were killed.^[57]

On 12 May several Hurricanes units were committed to escort bombers. That morning, five Fairey Battle volunteer crews from 12 Squadron took off from Amifontaine base to bomb Vroenhoven and Veldwezelt bridges on the Meuse, at Maastricht. The escort consisted of eight Hurricanes of 1 Squadron, with Squadron Leader P. J. H. "Bull" Halahan in the lead. When the formation approached Maastricht, it was bounced by 16 Bf 109Es from 2./JG 27. Two Battles and two Hurricanes (including Halahan's) were shot down, two more Battles were brought down by flak and the fifth bomber had to crash-land. The 1 Squadron pilots claimed four Messerschmitts and two Heinkel He 112s,^{[N 3]} while the Luftwaffe actually lost only one Bf 109.^[58][59]

On 13 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. The following day, Hurricanes suffered heavy losses: 27 being shot down, 22 by Messerschmitts, with 15 pilots killed (another died some days later), including Squadron Leader J. B. Parnall (504 Squadron),^{[N 4]} and the Australian ace Flying Officer Les Clisby (1 Squadron).^{[60][N 5]} On the same day, 3 Squadron claimed 17 German aircraft shot down, 85 and 87 Squadrons together claimed four victories, while 607 Squadron claimed nine.^[61] During the following three days (15–17 May), no fewer than 51 Hurricanes were lost, in combat or in accidents.^[62]

Mechanics servicing the engine of a Hurricane I of 501 Squadron at No. 1 Repair Centre, Reims, Champagne, France

By 17 May, the end of the first week of fighting, only three of the squadrons were near operational strength, but the Hurricanes had managed to destroy nearly twice as many German aircraft.^[63] On 18 May 1940, air combat continued from dawn to dusk; Hurricane pilots claimed 57 German aircraft and 20 probables (Luftwaffe records show 39 aircraft lost). The following day, 1 and 73 Squadrons claimed 11 German aircraft (three by "Cobber" Kain and three by Paul Richey). On these two days Hurricanes suffered heavier losses, with 68 Hurricanes shot down or forced to crash-land due to combat damage. Fifteen pilots were killed, eight were taken prisoner and 11 injured. Two-thirds of the Hurricanes had been shot down by Messerschmitt Bf 109s and Bf 110s.^[64]

In the afternoon of 20 May 1940, the Hurricane units based in northern France were ordered to abandon their bases on the continent and return to Great Britain. On the same day, "Bull" Halahan requested the repatriation of the pilots serving in 1 Squadron. During the previous 10 days, the unit had been the most successful of the campaign; it had claimed 63 victories for the loss of five pilots: two killed, one taken prisoner and two hospitalised. 1 Squadron was awarded 10 DFCs and three DFMs during the Blitzkrieg.^[65] On the evening of 21 May, the only Hurricanes still operational were those of the AASF that had been moved to bases around Troyes.^[66]

During the 11 days of fighting in France and over Dunkirk from 10 to 21 May, Hurricane pilots claimed 499 kills and 123 probables. Contemporary German records, examined postwar, attribute 299 Luftwaffe aircraft destroyed and 65 seriously damaged by RAF fighters.^[67] The last 66 Hurricanes of the 452 engaged during the Battle of France left France on 21 June; 178 were abandoned at several airfields, notably Merville, Abbeville, and Lille/Seclin.^[66][68]

Operation Dynamo

During Operation Dynamo (the evacuation from Dunkirk of British, French and Belgian troops cut off by the German army during the Battle of Dunkirk), the Hawker Hurricanes operated from British bases. Between 26 May and 3 June 1940, the 14 Hurricane units involved were credited with 108 air victories. A total of 27 Hurricane pilots became aces during Operation Dynamo, led by Canadian Pilot Officer W. L. Willie McKnight (10 victories) and Pilot Officer Percival Stanley Turner (seven victories), who served in No. 242 Squadron, consisting mostly of Canadian personnel.^[69] Losses were 22 pilots killed and three captured.^[70]

On 27 May 1940, in one of the final mass encounters of the Blitzkrieg, 13 Hurricanes from 501 Squadron intercepted 24 Heinkel He 111s escorted by 20 Bf 110s; during the ensuing battle, 11 Heinkels were claimed as "kills" and others damaged, with little damage to the Hurricanes.^[72] On 7 June 1940, "Cobber" Kain, the first RAF ace of the war, got word that he was to return to England for "rest leave" at an Operational Training Unit. On leaving his airfield, he put on an impromptu aerobatic display and was killed when his Hurricane crashed after completing a loop and attempting some low altitude "flick" rolls.^[73]

Initial engagements with the Luftwaffe had 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 obsolete.^[39] At the start of the war, the engine ran on standard 87 octane aviation spirit. From early 1940, increasing quantities of 100 octane fuel imported from the U.S. became available.^[74][75] In February 1940, Hurricanes with the Merlin II and III engines began to receive modifications to allow for an additional 6 psi (41 kPa) of supercharger boost for five minutes (although there are accounts of its use for 30 minutes continuously).^[76]

The extra supercharger boost, which increased engine output by nearly 250 hp (190 kW), gave the Hurricane an approximate increase in speed of 25 to 35 mph (40 to 56 km/h), under 15,000 ft (4,600 m)^[76] altitude and greatly increased the aircraft's climb rate. "Overboost" or "pulling the plug", a form of war emergency power as it was called in later Second World War aircraft, was an important wartime modification that allowed the Hurricane to be more competitive against the Bf 109E and to increase its margin of superiority over the Bf 110C, especially at low altitude. With the +12 psi (83 kPa) "emergency boost", the Merlin III was able to generate 1,310 hp (980 kW) at 9,000 ft (2,700 m).^[77]

Flight Lieutenant Ian Gleed of 87 Squadron wrote about the effect of using the extra boost on the Hurricane while chasing a Bf 109 at low altitude on 19 May 1940: "Damn! We're flat out as it is. Here goes with the tit.^{[N 6]} A jerk – boost's shot up to 12 pounds; speed's increased by 30 mph. I'm gaining ground – 700, 600, 500 yards. Give him a burst. No, hold your fire you fool! He hasn't seen you yet..."^[76] Gleed ran out of ammunition before he could shoot the 109 down although he left it heavily damaged and flying at about 50 ft (15 m).^{[N 7]}

Hurricanes equipped with Rotol constant-speed propellers were delivered to RAF squadrons in May 1940, with deliveries continuing throughout the Battle of Britain. According to aviation author David Donald, the Rotol propeller had the effect of transforming the Hurricane's performance from "disappointing" to "acceptable mediocrity"; modified aircraft were reportedly much sought after among squadrons which had also been equipped with Hurricanes that were fitted with the older de Havilland two-position propeller.^[78][79]

Battle of Britain

At the end of June 1940, following the fall of France, 31 of Fighter Command's 61 fighter squadrons were equipped with Hurricanes.^[80] The Battle of Britain officially lasted from 10 July until 31 October 1940, but the heaviest fighting took place between 8 August and 21 September. Both the Supermarine Spitfire and the Hurricane are renowned for their part in having defended Britain against the Luftwaffe; generally, the Spitfires intercepted the German fighters, leaving Hurricanes to concentrate on the bombers, and, despite the undoubted abilities of the "thoroughbred" Spitfire, it was the "workhorse" Hurricane that scored the higher number of RAF victories during this period, accounting for 55% of the 2,739 German losses, according to Fighter Command, compared with 42% by Spitfires.^[81] On 8 August 1940, Hurricanes of No. 145 Squadron were recorded as having fired the first shots of the Battle of Britain.^[82] The highest scoring Hurricane squadron during the Battle of Britain was the No. 303 Polish Fighter Squadron. This squadron also had the distinction of having the highest ratio of enemy aircraft destroyed to own losses suffered.^[83][84][85]

Hurricane I of 1 Squadron flown by Plt Off A.V. Clowes.

As a fighter, the Hurricane had some drawbacks. It was slightly slower than both the Spitfire I and II and the Messerschmitt Bf 109E, and the thicker wing profiles compromised acceleration; but it could out-turn both of them. In spite of its performance deficiencies against the Bf 109, the Hurricane was still capable of destroying the German fighter, especially at lower altitudes. The standard tactic of the 109s was to attempt to climb higher than the RAF fighters and "bounce" them in a dive; the Hurricanes could evade such tactics by turning into the attack or going into a "corkscrew dive", which the 109s, with their lower rate of roll, found hard to counter. If a 109 was caught in a dogfight, the Hurricane was just as capable of out-turning the 109 as the Spitfire. In a stern chase, the 109 could evade the Hurricane.^[87]

In September 1940, the more powerful Mk.IIa series 1 Hurricanes started entering service, although only in small numbers.^[88] This version was capable of a maximum speed of 342 mph (550 km/h).^[89] The Hurricane was a steady gun platform and had demonstrated its ruggedness as several were badly damaged yet returned to base.^[90] The Hurricane's construction made it dangerous if it caught fire; the wood frames and fabric covering of the rear fuselage allowed fire to spread through the rear fuselage structure easily. The gravity fuel tank in the forward fuselage sat right in front of the instrument panel, without any form of protection for the pilot. Many Hurricane pilots were seriously burned as a consequence of a jet of flame which could burn through the instrument panel. This became of such concern to Hugh Dowding that he had Hawker retrofit the fuselage tanks of the Hurricanes with Linatex, a self-expanding rubber coating.^[91] If the tank happened to be punctured by a bullet, the Linatex coating expanded when soaked with petrol and sealed it.^[92] However, some Hurricane pilots felt that the fuel tanks in the wings, although they were also protected with a layer of Linatex, were vulnerable from behind, and it was thought that those, and not the fuselage tank, were the main fire risk.^[93][94]

Groundcrew refuelling a Hurricane Mk.I of 32 Squadron, RAF Biggin Hill, Bromley, London, August 1940

From 10 July to 11 August 1940, 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%. It has been suggested that part of the success of the British fighters was possibly due to the use of the de Wilde incendiary round.^[95] The Hurricane with the highest number of kills during the Battle of Britain was P3308, a Mk.I, flown between 15 August and 7 October 1940 by RAF (auxiliary) pilot Archie McKellar of 605 Squadron.^[96] He is credited with 21 kills, 19 of those in a Hurricane during the Battle of Britain. On 7 October he is credited with shooting down five Bf 109s, making him one of only two RAF pilots (the other being Brian Carbury of New Zealand) to become an "ace in a day" during the Battle of Britain.^[97][98] During his brief fighting career, McKellar earned the DSO,^[99] DFC & Bar.^[100][101] McKellar has remained in relative obscurity in Battle of Britain history, as he was killed in action one day after the date set by the War Ministry (after the war) as the official end date for the Battle of Britain. He died on 1 November 1940 while taking on a superior number of Bf 109s.^[102] As in the Spitfire, the Merlin engine suffered from negative-G cut-out, a problem not cured until the introduction of Miss Shilling's orifice in early 1941.

303 squadron pilots. L-R: F/O Ferić, F/Lt Lt Kent, F/O Grzeszczak, P/O Radomski, P/O Zumbach, P/O Łokuciewski, F/O Henneberg, Sgt Rogowski, Sgt Szaposznikow (in 1940).

The only Battle of Britain Victoria Cross, and the only one awarded to a member of Fighter Command during the war,^[103] was awarded to Flight Lieutenant James Brindley Nicolson of 249 Squadron as a result of an action on 16 August 1940 when his section of three Hurricanes was "bounced" from above by Bf 110 fighters. All three were hit simultaneously. Nicolson was badly wounded, and his Hurricane was damaged and engulfed in flames. While attempting to leave the cockpit, Nicolson noticed that one of the Bf 110s had overshot his aircraft. He returned to the cockpit, which by now was in an inferno, engaged the enemy, and may have shot down the Bf 110.^{[104][105][N 8]} Afterward, he parachuted to safety, although he was mistakenly shot at by the Home Guard after landing.

Night fighters and intruders

Wartime colour photo of Hurricane IIC BE500 flown by Sqn Ldr Denis Smallwood of 87 Squadron in the RDM2 ("Special Night") scheme and used on intruder operations 1941–1942.

Following the Battle of Britain the Hurricane continued to give service; through the Blitz of 1941 it was the principal single-seat night fighter in Fighter Command. F/Lt. Richard Stevens claimed 14 Luftwaffe bombers flying Hurricanes in 1941. In 1942 the cannon-armed Mk.IIc performed further afield, as a night intruder over occupied Europe. F/Lt. Karel Kuttelwascher of 1 Squadron proved the top scorer, with 15 Luftwaffe bombers claimed shot down. The year 1942 also saw the manufacture of 12 Hurricane II C(NF) night fighters, equipped with pilot-operated air interception Mark VI radar. After a brief operational deployment with No. 245 and No. 247 Squadron RAF during which these aircraft proved too slow for operations in Europe, the aircraft were sent to India to serve with No. 176 Squadron RAF in the defence of Calcutta.^[107] They were withdrawn from service at the end of December 1943.^[108]

North Africa

Maintenance work being carried out on a Hurricane of 274 Squadron during the siege of Tobruk

A Hurricane Mk.I undertook tropical trials in Sudan in mid 1939, and a number were hastily tropicalised following Italy's entry into the war in June 1940.^[109] These aircraft were initially ferried through France and Malta by air to 80 Squadron in Egypt, replacing Gladiator biplanes.^[110] The Hurricane claimed its first kill in the Mediterranean on 19 June 1940, when F/O P.G. Wykeham-Barnes reported shooting down two Fiat CR.42 Falcos.

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 by Curtiss Tomahawks/Kittyhawks. However, fighter-bomber variants ("Hurribombers") retained an edge in the ground attack role, due to their impressive armament of four 20 mm (0.79 in) cannon and a 500 lb (230 kg) bomb load.

From November 1941, beginning in the Libyan desert, it had to face a new formidable opponent: the new Regia Aeronautica Macchi C.202 Folgore. The Italian aircraft proved superior to the Hawker fighter^[112] and, thanks to its excellent agility and a new, more powerful inline engine licence-built by Alfa Romeo, could outperform it in a dogfight.^[113]

During and following the five-day Second Battle of El Alamein artillery barrage that commenced on the night of 23 October 1942, six squadrons of Hurricanes, including the 40 mm (1.57 in) cannon-armed Hurricane Mk.IID version, 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, 10 lorries, five half-tracks, a gun and trailer, and a wireless van on 10 March 1943, with no losses to themselves.^[114]

In the spring of 1943, during the German Ochsenkopf offensive in Tunisia, Hurricane IIDs conducted many sorties after fog had lifted, helping to blunt the final attack at Hunts Gap.^[115]

Defence of Malta

The Hurricane played a significant role in the defence of Malta. When Italy entered the war on 10 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 17 days. Initially there were six Gladiators, though after a while, only three were able to be flown at any one time because of a shortage of spare parts, and for whatever reason (five different explanations have been given), they became known as "Faith, Hope and Charity".^[116] 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 2 August in the form of 12 more Hurricanes and two Blackburn Skuas.^{[117] [N 9]}

The increasing number of British aircraft on the island, at last, prompted the Italians to employ German Junkers Ju 87 dive bombers to try to 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, the Luftwaffe left Sicily for the Russian Front in June that year.^[119]

As Malta was situated on the increasingly important sea supply route for the North African campaign, the Luftwaffe returned with a vengeance for a second assault on the island at the beginning of 1942. It was not until March, when the onslaught was at its height, that 15 Spitfires flew in off the carrier HMS Eagle to bolster the defence, but many of the new aircraft were lost on the ground and the Hurricane bore the brunt of the early fighting until further reinforcements arrived.^[118]

Air defence in the Soviet Union

Hurricane Mk.IIB of No. 81 Squadron RAF at Murmansk-Vaenga airfield, Russia

The Hawker Hurricane was the first Allied Lend-Lease aircraft to be delivered to the Soviet Union with a total of 2,952 Hurricanes eventually delivered,^[120] becoming the most numerous British aircraft in Soviet service.^[121] Many Soviet pilots were disappointed by the Hawker fighter, regarding it as inferior to both German and Soviet aircraft.^[120][122] In July 2023, a crate of 8 Hurricanes was found buried in Ukraine. These had been supplied by the US but under the terms of Lease Lend, the Russians did not have to pay for equipment which didn't survive the war. ^[123]

During 1941, Mk.II Hurricanes played an important air defence role when the Soviet Union found itself under threat from the approaching German Army, who were advancing across a broad front stretching from Leningrad and Moscow to the oil fields in the south. Britain's decision to aid the Soviets meant sending supplies by sea to the far northern ports, and as the convoys needed to sail within range of enemy air attack from the Luftwaffe based in neighbouring Finland, it was decided to deliver a number of Hurricane Mk.IIBs, flying with Nos. 81 and 134 Squadrons of No. 151 Wing RAF, to provide protection. Twenty-four were transported on the carrier Argus, arriving just off Murmansk on 28 August 1941, and another 15 crated aircraft on board merchant vessels. In addition to their convoy protection duties, the aircraft also acted as escorts to Soviet bombers. Enemy attention to the area declined in October, at which point the RAF pilots trained their Soviet counterparts to operate the Hurricanes themselves. By the end of the year, the RAF's direct role in the region had ended, but the aircraft themselves remained behind and became the first of thousands of Allied aircraft that were accepted by the Soviet Union.^[124] Although Soviet pilots were not universally enthusiastic about the Hurricane, twice Hero of the Soviet Union Lt. Col. Boris Safonov "loved the Hurricane", and RAF Hurricane Mk.IIB fighters operating from Soviet soil in defence of Murmansk, destroyed 15 Luftwaffe aircraft for only one loss in combat.^[125] However, in some Soviet war memoirs, the Hurricane has been described in very unflattering terms.^[126]

The "Soviet" IIB Hurricane as a multi-role fighter-bomber had quite a few drawbacks. First of all, it was 25–31 mph (40–50 km/h) slower than its main opponent, the Bf 109E interceptor, at low and medium height, and had a slower rate of climb. The Messerschmitt could outdive the Hurricane because of the thicker wing profile of the British fighter. But the main source of complaints was the Hurricane's armament. On occasion, the eight or 12 rifle-calibre machine guns did not damage the sturdy and heavily armoured German aircraft; consequently, Soviet ground crews started to remove the Brownings. Retaining only four or six of the 12 machine guns, two 12.7 mm (0.50 in) Berezin UBs or two or even four 20 mm (0.79 in) ShVAK cannons were substituted, but overall performance deteriorated as a result.^{[127][N 11]}

The British archives file AIR 22/310 reports 218 Mk.IIA sent to the Soviet Union or handed over, 22 lost before arrival, 1,884 Mk.IIB sent or handed over, 278 lost before arrival, 1,182 Mk.IIC sent or handed over, 46 lost before arrival, 117 rejected, 60 IID sent or handed over, 14 rejected, 30 Mk.IV handed over, total 3,374 Hurricanes sent or handed over, 346 lost before delivery, 2,897 accepted by the Soviets, 131 rejected.

Far East

Hawker Hurricane Mk.IIB/Trop of 488 Squadron RNZAF at RAF Kallang, January 1942

Following the outbreak of the war with Japan, 51 Hurricane Mk.IIBs en route to Iraq were diverted to Singapore; 10 were in crates, the others partially disassembled, these and the 24 pilots (many of whom were veterans of the Battle of Britain), who had been transferred to the theatre, formed the nucleus of five squadrons. They arrived on 13 January 1942, by which time the Allied fighter squadrons in Singapore, flying Brewster Buffalos, had been overwhelmed during the Malayan campaign. The fighters of the Imperial Japanese Army Air Force, especially the Nakajima Ki-43 Oscar, had been underestimated in its capability, numbers and the strategy of its commanders.^[129][130]

Thanks to the efforts of the 151st Maintenance Unit, the 51 Hurricanes were assembled and ready for testing within 48 hours and of these, 21 were ready for operational service within three days. The Hurricanes, originally intended for the Middle East theatre, were fitted with bulky 'Vokes' dust filters under the nose and were armed with twelve, rather than eight, machine guns. The additional weight and drag made them slow to climb and unwieldy to manoeuvre at altitude, although they were more effective bomber killers.^[131]

The recently arrived pilots were formed into 232 Squadron and 488 (NZ) Squadron, flying Buffalos, converted to Hurricanes. On 18 January, the two squadrons formed the basis of 226 Group; 232 Squadron became operational on 22 January and suffered the first losses and victories for the Hurricane in Southeast Asia.^[132] Between 27 and 30 January, another 48 Hurricanes Mk.IIB arrived with the aircraft carrier HMS Indomitable, from which they flew to airfields code-named P1 and P2, near Palembang, Sumatra in the Netherlands East Indies.

The Hurricanes first saw action on the morning of 20 January 1942, when twelve aircraft of 232 Squadron intercepted a mixed IJN and IJAAF formation of about 80 bombers escorted by fighters, the heaviest air raid on Singapore. Eight were claimed shot down and three probables, but three Hurricanes were lost along with two pilots, including Squadron Leader Leslie Ninian Landels.^{[133][134][135]}

Because of inadequate early warning systems (the first British radar stations became operational only towards the end of February), Japanese air raids were able to destroy 30 Hurricanes on the ground in Sumatra, most of them in one raid on 7 February. After Japanese landings in Singapore, on 10 February, the remnants of 232 and 488 Squadrons were withdrawn to Palembang. Japanese paratroopers began the invasion of Sumatra on 13 February. Hurricanes destroyed six Japanese transport ships on 14 February but lost seven aircraft in the process. On 18 February, the remaining Allied aircraft and aircrews moved to Java, with only 18 serviceable Hurricanes out of the original 99.^[136] That month, 12 Hurricane Mk.IIB Trops were supplied to the Dutch forces on Java. With dust filters removed and fuel and ammo load in wings halved, these were able to stay in a turn with the Oscars they fought.^[137] After Java was invaded, some of the New Zealand pilots were evacuated by sea to Australia.

Hurricane V7476 sent to Australia in May 1941, arriving in August, was the only Hurricane based in Australia during the Second World War. The tropicalised Vokes air filter, which was fitted to many types operating in the Pacific, is visible under the nose.

When a Japanese carrier task force under the command of Admiral Chūichi Nagumo made a sortie into the Indian Ocean in April 1942, RAF Hurricanes based on Ceylon saw action against Nagumo's forces during attacks on Colombo on 5 April 1942 and on Trincomalee harbour on 9 April 1942.^[138]

On 5 April 1942, Captain Mitsuo Fuchida of the Imperial Japanese Navy, who led the attack on Pearl Harbor, led a strike against Colombo with 53 Nakajima B5N torpedo bombers and 38 Aichi D3A dive bombers, escorted by 36 Mitsubishi A6M Zero fighters.^[139] They were opposed by 35 Hurricane I and IIBs of 30 and 258 Squadrons, together with six Fairey Fulmars of 803 and 806 Naval Air Squadrons of the Fleet Air Arm.^[140] The Hurricanes mainly tried to shoot down the attacking bombers, but were engaged heavily by the escorting Zeros.^[141] A total of 21 Hurricanes were shot down (although two of these were repairable),^[142] together with four Fulmars^[143] and six Swordfish of 788 Naval Air Squadron that had been surprised in flight by the raid.^[144] The RAF claimed 18 Japanese aircraft destroyed, seven probably destroyed and nine damaged, with one aircraft claimed by a Fulmar and five by anti-aircraft fire. This compared with actual Japanese losses of one Zero and six D3As, with a further seven D3As, five B5Ns and three Zeros damaged.^[141][145]

On 9 April 1942, the Japanese task force sent 91 B5Ns escorted by 41 Zeros against Trincomalee port and the nearby China Bay airfield.^[146] Sixteen Hurricanes opposed the raid, of which eight were lost with a further three damaged.^[147] They claimed eight Japanese aircraft destroyed with a further four probably destroyed and at least five damaged. Actual Japanese losses were three A6Ms and two B5Ns, with a further 10 B5Ns damaged.^[148]

The battles over the Arakan in 1943 represented the last large-scale use of the Hurricane as a pure day fighter. But they were still used in the fighter-bomber role in Burma until the end of the war and they were occasionally caught up in air combat as well. For example, on 15 February 1944, Flg Off Jagadish Chandra Verma of No. 6 Squadron of the Royal Indian Air Force shot down a Japanese Ki-43 Oscar: it was the only RIAF victory of the war.^[149] The Hurricane remained in service as a fighter-bomber over the Balkans and at home as well where it was used mainly for second-line tasks and occasionally flown by ace pilots. For example, in mid-1944, ace Squadron Leader "Jas" Storrar flew No 1687 Hurricane to deliver priority mail to Allied armies in France during the Normandy invasion.^[149]

Aircraft carrier operations

Sea Hurricane Mk.IB in formation, December 1941

The Sea Hurricane became operational in mid-1941 and scored its first kill while operating from HMS Furious on 31 July 1941. During the next three years, Fleet Air Arm Sea Hurricanes were to feature prominently while operating from Royal Navy aircraft carriers. The Sea Hurricane scored an impressive kill-to-loss ratio,^{[150][N 12]} primarily while defending Malta convoys, and operating from escort carriers in the Atlantic Ocean. For example, on 26 May 1944, Royal Navy Sea Hurricanes operating from the escort carrier HMS Nairana claimed the destruction of three Ju 290 reconnaissance aircraft during the defence of a convoy.^[151]

Finland

Finnish Hurricane Mk.I at the Finnish Air Force Museum

During the Winter War, Finnish Air Force were in dire need of modern fighters and sourced them from several countries, including the United Kingdom. Finland bought 12 Hurricanes and the delivery commenced on 2 February 1940. The Hurricanes were flown from St Athan, Wales to Västerås, Sweden, via Scotland and Norway by Finnish pilots in two batches. The first batch arrived in Västerås on 29 February, with the last aircraft arriving on 10 March. During the second batch flight, two Hurricanes were lost, with one crashing in Norway and the other being damaged during landing in Scotland and left there.^[152] The Hurricanes were initially deployed to LLv 22. Later they were transferred to LLv 28 and finally moved to LLv 30. During the period of Interim Peace, two further Hurricanes were lost in accidents.^[152]

At the start of the Continuation War on 25 June 1941, the Hurricanes were allocated to LLv 30. On 2 July 1941, a Hurricane were mistakenly shot down by friendly anti-aircraft at Vainikkala. The Finnish Hurricanes' first combat came on 3 July, when three Hurricanes encountered several Soviet fighters and shot down an I-153 "Chaika". In the next day, the Hurricane shot down a Tupolev SB bomber.^[152] Other encounters with Soviet fighters took place on 15 July above the Karelian Isthmus, with two I-153 claimed as being shot down. The last aircraft shot down by Finnish Hurricanes was an I-15 on 6 January 1942.^[153]

Bibliography