Poland’s first Hurricanes were bought in 1939 but only one from an order for ten was delivered before the German invasion, the remaining nine being allocated to the RAF or diverted to Turkey instead. However, several expatriate Polish pilots flew Hurricanes within the RAF, with the first Polish-manned squadrons forming in Britain in 1940, of which Nos.302 and 303 (Polish) Squadrons took part in the Battle of Britain.
In total, seven Polish-manned squadrons, each named after a Polish city or individual, operated various Marks of Hurricane, namely: No.302 (City of Poznan); No.303 (Kosciuszko); No.306 (City of Torun); No.308 (City of Krakow); No.315 (City of Deblin); No.316 (City of Warsaw); No.317 (City of Wilno)
Pilots from 303 (Polish) Squadron: From the left Pilot Officer Miroslaw Feric, Flight Lieutenant John Kent, Pilot Officer Bohdan Grzeszczak, Pilot Officer Jerzy Radomski and Pilot Officer Jan Zumbach in the background, Pilot Officer Witold Lokuciewski, Flying Officer Zdzislaw Henneberg, Sergeant January Rogowski and Sergeant Eugeniusz Szaposznikow.
The Hurricane’s baptism of fire came on 21 October 1939, when A Flight of No.46 Squadron took off from RAF Digby, Lincolnshire, 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 He 115s had already been attacked and damaged by two No.72 Squadron Spitfires when the six No.46 Squadron Hurricanes intercepted the Heinkels which were flying at sea level in an attempt to avoid further attacks. Nevertheless the Hurricanes shot down three of them in rapid succession and damaged another (although No.46 claimed five and No.72 claimed two!)
By late 1939/1940, many of the early delivery machines were in the process of being updated with ‘metal’ wings, 1,030hp Merlin III engines, ejector exhaust manifolds, de Havilland and Rotol variable speed three-blade propellers, reflector gunsights instead of the original ring and bead type, internal and external armoured windscreens and armour-plated rear cockpit bulkheads – none of which could be achieved overnight of course – resulting in a range of modifications, for a while, that numbered an estimated twenty-seven different standards.
The Phoney War
In response to a request from the French government for ten fighter squadrons to provide air support, in addition to ten squadrons of Fairey Battles that were flown to bases in metropolitan France in late August/early September 1939, Air Chief Marshal Sir Hugh Dowding, Commander-in-Chief of RAF Fighter Command, argued that this number of fighters would severely deplete Fighter Command’s British defences, and so initially only a token force of four Hurricane squadrons, Nos.1, 73, 85 and 87, were sent to France in early September 1939, (all Spitfires being retained for Home defence). The RAF supplied two air contingents initially – the Advanced Air Striking Force (AASF) and the Air Component of the British Expeditionary Force (BEF). The four Hurricane squadrons initially formed No.60 Wing within the Air Component of the BEF, but by the middle of September further RAF squadrons comprising Blenheim IV bombers and Lysander tactical reconnaissance and army co-operation aircraft started arriving. Over the following autumn and winter, the squadrons were rotated around various bases while Nos.1 and 73 Squadrons were detached from the BEF’s Air Component control during the winter to form No.67 Fighter Wing attached directly to the AASF.
On 30 October, Hurricane pilots experienced their first action over France. Pilot Officer P. W. O ‘Boy’ Mould of No.1 Squadron, flying L1842, shot down a Dornier Do 17P from 2.(F)/123, sent to photograph allied airfields close to the border, about 10 miles west of Toul, becoming the first RAF pilot to down an enemy aircraft on the continent in the Second World War. Flying Officer E. J. ‘Cobber’ Kain, a New Zealander, was responsible for No.73 Squadron’s first victory, on 8 November 1939, whilst stationed at Rouvres. He went on to become one of the RAF’s first ‘aces’ of the war, being credited with sixteen ‘kills’ before his death in a flying accident on 6 June 1940.
Hurricanes were also involved in the German invasion of Norway. On 9 April 1940, under codename Operation Weserübung the Wehrmacht invaded Denmark, which capitulated after a day, but Norway continued to resist. On 14 April Allied ground troops were landed in Norway, but by the end of the month, the southern parts of the country were in German hands. On 14 May 1940, No.46 Squadron embarked on HMS Glorious and sailed for an airfield near Harstad, Norway, to augment the Gladiators of No.263 Squadron operating from improvised airfields and the frozen lake at Lesjaskog, but they had to return with the carrier to Scapa Flow when the landing ground was found to be unusable.
On 26 May, ten of the squadron’s Hurricanes were flown off to Skaanland, but due to the soft surface two crashed on landing so the remainder were diverted to Bardufoss, sixty miles further north. After providing fighter cover for the Narvik area for two weeks the order to evacuate all Allied forces from Norway was received and, on 7 June, despite the lack of arrester hooks and no deck landing training, the squadron flew its surviving Hurricanes back on to Glorious’ deck – all landing safely. The squadron’s ground crews embarked in other ships and re-assembled at Digby, though tragically, HMS Glorious and her destroyer escort were intercepted by the German battleships Scharnhorst and Gneisenau during their return home, and sunk. Only two RAF officers survived the sinking, one being No.46’s CO, Squadron Leader K. B. B. (later Air Chief Marshal Sir Kenneth) Cross. Despite this disaster the squadron was operational again by the end of June, at Digby.
Battle of France
By the spring of 1940, it became rapidly apparent that the handful of Hurricane squadrons based in France would be woefully inadequate to offset an impending Luftwaffe avalanche. In May, three more Hurricane squadrons, Nos.3, 79 and 504, were sent to reinforce the earlier units as Germany’s Blitzkrieg gathered momentum. On 10 May, the first day of the Battle of France, Hurricane squadrons claimed forty-two Luftwaffe aircraft shot down for the loss of seven Hurricanes with none of the pilots killed. Hurricane units also escorted bombers, including those involved with the raids against the Vroenhoven and Veldwezelt bridges on the Meuse, at Maastricht by No.12 Squadron’s Fairey Battles on 12 May. The escort consisted of eight Hurricanes from No.1 Squadron, but when the formation approached Maastricht, it was bounced by Bf 109Es from 2./JG 27. Two Battles and two Hurricanes were shot down, two more Battles were brought down by flak and the fifth was forced to crash land.
On 13 May 1940, more Hurricanes arrived, bringing the total of Hurricane squadrons operating from French soil to ten – Nos. 1, 3, 73, 79, 85, 87, 242, 501, 504 and 615 Squadrons (No. 615 having exchanged its Gladiators for Hurricanes in the preceding weeks) – but heavy losses continued and by the end of the first week of fighting only three of the squadrons remained near operational strength. With ferocious air combat continuing from dawn to dusk, throughout May, the order was finally received on the afternoon of 20 May 1940 for all Hurricane units based in northern France to abandon their bases and return to the UK. During eleven days of fighting in France, between 10 to 21 May, Hurricane units claimed 499 ‘kills’ and 123 probables, although contemporary German records examined post-war, attribute 299 Luftwaffe aircraft destroyed and sixty-five seriously damaged by RAF fighters. Number 1 Squadron was the most successful of the campaign, claiming sixty-three victories for the loss of five pilots. On the evening of 21 May, the only Hurricanes still operating in France were those of the AASF that had been moved to bases around Troyes and when the last Hurricanes left France, of the 452 Hurricanes sent only sixty-six returned to bases in the UK with over 170 having to be abandoned at their airfields.
During Operation Dynamo – the evacuation of British, French and Belgian troops cut off by the German army surrounding Dunkirk – Hurricanes continued to operate from British bases and it was over Dunkirk that the Luftwaffe suffered its first serious rebuff of the war. Although operating from captured bases in France, the Bf 109 was at the outer limits of its range and possessed less flying time over the area than the defending Hurricanes (and Spitfires) operating from airfields in southern England. Luftwaffe bombers, many still based in western Germany with farther to fly, found that British fighter attacks often prevented them from performing to their customary, often uninterrupted, degree of effectiveness and both sides suffered heavy losses, which for the Luftwaffe, came as a bit of a shock. For instance, Fliegerkorps II reported in its War Diary that it lost more aircraft on 27 May attacking the evacuation area than it had lost in the previous ten days of the campaign.
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 and its replacement with de Havilland and Rotol units was a priority. The Merlin III engine was designed to run on standard 87 octane aviation fuel, but from early 1940, increasing quantities of 100 octane fuel became available, which together with modifications to allow an additional 6psi of supercharger boost for five minutes, increased engine output by nearly 250hp and gave the Hurricane an approximate increase in speed of 25 to 35mph below 15,000ft, which greatly increased the aircraft’s climb rate. This form of emergency power was an important 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 lower altitudes.
Deliveries of new Hurricanes fitted with Rotol constant-speed propeller units (CSU) commenced in April/May 1940 and Hurricanes already in France were being retrofitted with Rotol CSUs by parties of the manufacturer’s engineers flying out from England to do the work. The Rotol CSU transformed the Hurricane’s performance and prompted de Havilland to undertake a modification programme of upgrading its older two-pitch propeller into a similar CSU, so that by the late spring/early summer of 1940, most frontline operational Hurricanes were fitted with either Rotol or de Havilland constant-speed propeller units.
The Battle of Britain
By the end of June 1940, following the fall and surrender of France on the 22nd, almost half of the RAF’s Fighter Command squadrons were equipped with Hurricanes. A short lull ensued whilst the Luftwaffe replaced its losses from the French Campaign and established itself on the airfields in the countries they had captured. In Britain this time was spent in putting as many new fighters and trained pilots into service as possible to prepare against the attack everyone knew was coming. The future of Britain was about to be decided in the skies above southeast England, and, as the country’s new Prime Minister, Winston Churchill, who took over the premiership on 10 May, put it, ‘What General Weygand called the Battle of France is over, the Battle of Britain is about to begin’
The Battle of Britain officially lasted from 10 July until 31 October 1940, with the heaviest fighting taking place between the beginning of August and mid-September. On 16 July, Hitler ordered the preparation of a plan to invade Britain, under ‘Directive No 16: The Preparation of a Landing Operation against England’ better known today as Operation Sealion. All preparations were to be made by mid-August and it was scheduled to take place in mid-September 1940. Sealion called for landings on the south coast of England, backed by an airborne assault. Neither Hitler nor the Oberkommando der Wehrmacht (OKW, Supreme Command of the Armed Forces), believed it would be possible to carry out a successful amphibious assault on Britain until the RAF had been neutralised. It was believed that air superiority might make a successful landing possible although it would still be a very risky operation requiring absolute mastery over the Channel by the Luftwaffe.
The Battle went through a series of phases:
Phase 1: From 10 July to 11 August 1940, which saw a series of running fights over convoys in the English Channel and occasional attacks on coastal shipping, convoys and harbours, such as Portsmouth, by Junkers Ju 87 Stuka dive bombers.
Phase 2: From 12 to 23 August 1940 when the Luftwaffe started to shift its attacks over to RAF airfields, the ground infrastructure and aircraft factories
Phase 3: Which saw intensified Luftwaffe attacks on RAF airfields from 24 August to 6 September 1940 – and came very close to destroying Fighter Command and its bases.
Phase 4: From 7 September to 31 October 1940, when the Luftwaffe changed its tactics and resorted to attacking areas of political significance such as London in daylight, using area bombing tactics.
Phase 5: From late September 1940 through to the spring of 1941 when the Luftwaffe turned more and more to a night bombing campaign against London and the UK’s major cities – known as ‘The Blitz’.
As may be imagined, with Hurricanes making up half of Fighter Command’s frontline force, the type was heavily committed to the Battle and Hurricane squadrons were involved in all the Phases, including some of the first nocturnal interceptions when the Luftwaffe started night bombing raids from late September. Despite the undoubted abilities of the Spitfire, it was the Hurricane that scored the higher number of victories during this period, accounting for almost 60 percent of the recorded 2,739 German losses. Although the Hurricane was slower than both the Spitfire and the Messerschmitt Bf 109E, with its thick wings which affected rapid acceleration, it could out-turn both of them. The Hurricane was a steady gun platform, and in spite of its performance differences compared to the Bf 109, the Hurricane was still a capable fighter, especially at lower altitudes. One tactic of the Bf 109 was to attempt to ‘bounce’ RAF fighters in a dive. If spotted in time, Hurricanes were able to 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 Bf 109 was engaged in a ‘straight dogfight’, the Hurricane was just as capable of out-turning it as the Spitfire, although in a stern chase, the Bf 109 could easily outpace and evade the Hurricane.
In the summer of 1940, Hurricane Is, (and Spitfire Is) were powered by Merlin III engines, fitted with a float chamber SU carburettor. When a Hurricane (or Spitfire) performed a negative-G manoeuvre (i.e. pitching the nose hard down), fuel was forced up to the top of the carburettor’s float chamber rather than into the engine, leading to loss of power. If the negative-G continued, then enough fuel would collect in the top of the float chamber to force the float to the floor of the chamber. This would in turn open a needle valve to maximum, flooding the carburettor and drowning the supercharger with an over-rich mixture which would lead to a cutout, thus shutting down the engine completely – a serious drawback in combat!
Bf 109s and Bf 110s used Daimler-Benz DB 601 inverted V12 engines fitted with fuel injection pumps, not carburettors, which kept their fuel at a constant pressure whatever manoeuvres they performed and did not suffer from this problem. They could exploit the difference by pitching steeply forward whilst pushing the throttle wide open; pursuing British fighters were left ‘flat footed’ as trying to emulate the manoeuvre would result in loss of power, or fuel flooding and engine shutdown. The only British countermeasure available was to half-roll, so the aircraft would only be subjected to positive-G as they followed a German aircraft into a dive, which invariably took just enough time to let the enemy escape.
Complaints from the pilots led Beatrice Tilly’ Shilling, a young engineer working at the Royal Aircraft Establishment (RAE) at Farnborough, to devise a disarmingly simple solution – a flow restrictor which was a small metal disc, much like a metal washer. The restrictor orifice was made to accommodate just the fuel needed for maximum engine power, the power setting usually used during dogfights. Whilst not completely solving the problem, the restrictor, along with modifications to the needle valve, permitted Hurricane and Spitfire pilots to perform quick negative-G manoeuvres without loss of engine power. In early 1941, Miss Shilling and a small team from the RAE travelled around Fighter Command’s airfields fitting these restrictors, giving priority to front-line units and by March 1941 the device had been installed throughout RAF Fighter Command. Officially named the ‘RAE restrictor’, the device was immensely popular with pilots, who affectionately named it ‘Miss Shilling’s orifice’ or simply the ‘Tilly orifice’. This simple solution was only ever a stopgap as it did not allow inverted flight for any length of time, however, the problems were ultimately overcome by the introduction of Bendix and later Rolls-Royce pressure-carburettors in 1943.