Whilst the Hurricane was rugged, sturdy and stable, another problem was the gravity fuel tank, situated in the forward fuselage, 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 flames burning through the instrument panel. This became of such concern that Hawker retrofitted the fuselage tanks with a self-expanding rubber coating called Linatex. If the tank happened to be punctured by a bullet, the Linatex coating would expand when soaked with petrol and seal it. As if to illustrate this point, mention can be made here of the only Victoria Cross awarded to a member of Fighter Command during the war, which occurred during the Battle of Britain. On 16 August 1940, Flight Lieutenant James Brindley Nicolson was leading a section of three No.249 Squadron Hurricanes over Southampton when they were ‘bounced’ by Messerschmitt Bf 110s. All three Hurricanes were hit and Nicolson was wounded in one eye and a foot. His Hurricane’s gravity tank was set alight engulfing the cockpit in flames. About to abandon his aircraft, Nicolson noticed that one of the Bf 110s had overshot his aircraft, so he remained in the cockpit, by now an inferno, fired at the enemy and then bailed out. Despite serious burns to his hands, face and legs, he managed to open his parachute in time, only to be fired on by a member of the Home Guard on his descent!
Even before the Battle of Britain officially commenced, Hurricanes were sent to fight elsewhere. On 10 June 1940, Italy, rushing to the aid of the German victor, declared war on France and Britain. Mussolini immediately took advantage of Britain’s preoccupation with its forthcoming battle to survive and called for an offensive throughout the Mediterranean. Within hours, the first bombs were dropped on Malta, a strategically significant British Crown Colony located between Gibraltar and Alexandria, a fortress island vital to Britain’s lifeline to Egypt (which Italy attacked in September), Suez, India and the Far East.
At the start of the Regia Aeronautica’s aerial bombardment of Malta, the only fighter defence comprised a small number of ex-Fleet Air Arm Gloster Sea Gladiators which together formed the Hal Far Fighter Flight.
However, the Flight was soon augmented by a few Hurricanes that had been flown across France prior to the latter’s surrender. All of the Hurricanes sent via this route were intended for the defence of Egypt, using Malta as a staging post, but, by dint of appeal, a total of five had been retained in Malta by 24 June (with six others continuing their journey to Egypt) to augment the Sea Gladiators. Of course there were no spare parts for Malta’s Hurricanes and by the end of June they were all grounded. Consequently, a dozen Hurricane Is were collected in the UK as No.418 Flight RAF which embarked aboard the small carrier HMS Argus in late July 1940 for urgent delivery to beleaguered Malta under Operation Hurry. By 2 August, Argus was southwest of Sardinia and all twelve Hurricanes were successfully launched. All reached Malta where they ultimately formed part of a new No.261 Squadron. This was the first in a long series of similar operations to ferry fighter aircraft to Malta using aircraft carriers, although the next attempt, Operation White, in November 1940, ended in disaster – just four of the twelve Hurricanes despatched arrived at Malta.
On 11 November, Argus again sailed from Liverpool with a deck load of another dozen Hurricanes for delivery to Malta (Operation White). However, due to a perceived threat of interception by the Italian Fleet it was decided to launch the Hurricanes when still 350 nautical miles west of Malta, the British admiral having been advised that the Hurricanes could safely cover 400 miles – within the ferrying range of both the Hurricanes and their escorting Skuas. Therefore, before dawn on 17 November, the first flight of six Hurricanes took off from Argus at 06:15hrs.
Given the correct speed and the best cruise range, the Hurricanes would have been left with just 45 minutes of fuel after reaching Malta, but they used up a lot of fuel whilst forming up, then the fighters flew at 150mph at 2,000ft, far from the ideal height and speed intended for their maximal range. The second wave was launched an hour later, as the convoy turned back at full speed. Unfortunately the wind veered from southwest to southeast, hampering the eastward path of the aircraft. A Sunderland flying boat met the first wave to lead them to Malta, even so two Hurricanes were lost after running out of fuel (one of the pilots was rescued by the Sunderland), while the four remaining Hurricanes and their accompanying Skua landed at Luqa at 09:20hrs.
Unfortunately the second flight were denied their Sunderland escort because it failed to take off from Gibraltar. They also missed a bomber sent from Malta to replace the Sunderland. All of the Hurricanes ran out of fuel and crashed into the sea, with the loss of all the pilots, only the accompanying Skua survived to crash-land in Sicily just before it too ran out of fuel.
Following the fall of France, and given the Royal Navy’s shortage of aircraft carriers, an alternate method of supply was pioneered in order to provide Egypt with more aircraft. The method chosen was the Takoradi Route. Situated on the Gold Coast (a British colony on the Gulf of Guinea in West Africa which became Ghana in 1957), crated aircraft, including Hurricanes, were delivered by sea to Takoradi, assembled and test flown there, then ferried across Africa to Khartoum – a route first pioneered by Air Vice-Marshal Arthur Coningham in 1925. The Takoradi Route to Egypt was first used by RAF aircraft in September 1940, when one Blenheim guided six Hurricanes to their destination.
By the end of November 1940, the RAF in Egypt had been bolstered by sufficient Hurricanes to equip Nos.73 and 274 Squadrons, ready for the beginning of Operation Compass, the first major British military operation of the Western Desert Campaign in the Second World War, when, from December 1940 to February 1941, British and Commonwealth forces attacked the Italians in western Egypt and eastern Libya. The operation was a complete success with the Hurricanes, Blenheims and Lysanders, finding it hard to keep pace with the ground forces, often landing after a sortie at a more advanced strip than the one from which they had set out.
In the autumn of 1940, the Hurricane IIa Series I started entering service, albeit in small numbers at first. Powered by the 1,480hp Merlin XX, which utilised a two-speed supercharger resulting in increased power at higher altitudes, it was designed from the outset to run on 100 octane fuel which allowed higher manifold pressures – achieved by increasing the boost from the centrifugal supercharger – giving the Mk.II a maximum speed of 340mph. Another improvement, was the use of a 70/30 per cent water/glycol coolant mix rather than the 100 per cent glycol of earlier versions. This substantially improved engine life and reliability, removed the fire hazard of the inflammable ethylene glycol, and reduced the oil leaks that had been a problem with the early Merlin I, II and III series of engines.
The new engine was longer than earlier Merlins and so the Hurricane gained a 4½ inch ‘plug’ in front of the cockpit firewall, which had the added benefit of making the aircraft slightly more stable due to the slight forward shift in its centre of gravity. The Rotol CSU unit was now housed within a specially designed, more aerodynamically pointed, propeller spinner, the original ‘blunt’ spinner having originally been designed for the Spitfire which possessed a slightly greater diameter nose contour than the Hurricane. Additionally, Dowty levered-suspension units with a ‘knuckled’ torque-link tailwheel leg bagan to replace the straight-legged internally sprung Hawker/Lockheed design introduced on the Mk.I.
Well before the outbreak of war, it was realised that the increasing speeds and robustness of aircraft would call for something more powerful than the .303inch riflecalibre machine gun, eight of which were fitted to the Hurricane and Spitfire at the time. The rapid introduction of armour protection during 1940 greatly reduced the effectiveness of rifle-calibre guns, especially against bombers which, whilst being easier to hit, were more difficult to destroy. Many German bombers returned to base despite being riddled by .303 bullets, protected as they often were by crew seat armour and selfsealing fuel tanks. Increasing the number of .303 machine guns to twelve in the Hurricane IIb was one attempt to achieve a greater weight of fire, but a bigger gun was needed.
Extensive tests by Browning and Vickers of .50 calibre heavy machine guns and 20mm cannon in the 1920s had provided important information, but the .50s were rejected: not only were they much heavier and slower firing than the .303s, they did not have the benefit of an effective high-explosive shell. Hence the RAF decided to look for a 20mm cannon and, in 1935, the Air Staff ordered a French Dewoitine 510 Fighter equipped with a single engine-mounted Hispano Suiza 20mm Moteur Cannon. The D.510 and its gun, which outclassed any similar weapon on the market at this time, commenced flight trials at Martlesham Heath in 1937.
Thereafter a significant effort was made to get the Hispano 20mm cannon into service, but despite its high priority, the problems associated with acquiring manufacturing rights, redesigning the gun’s feed mechanism and setting up a suitable manufacturing process delayed matters. Further, problems would be experienced in adapting the gun to fit within the wings of both the Hurricane and Spitfire, it often being overlooked that the Moteur Cannon was designed to sit within the rigid, non-flexing, environment of an engine cylinder block. (This fact also accounted for the gun’s length as the barrel had to clear the propeller boss. Much later, when the Hispano V was being developed to replace the Mk.II it was discovered that 12 inches could be lopped off of the barrel without materially affecting its ballistic properties.)
Number 19 Squadron, was equipped with modified Spitfire Is that had been fitted with re-built wings, each armed with a 20mm Hispano, and tested in June/July 1940. The results were disappointing; the gun did not respond well to being mounted on its side (in order to enclose the drum magazine within the Spitfire’s thin wing), nor to being installed in a wing that flexed in flight. Reliability was so poor and stoppages so frequent, that the squadron asked for its .303-armed Spitfires back.
Hawker had also experimented with improving the armament of its fighter by fitting cannon. The first trials used the 20mm Hispano I – one fitted beneath each wing in a streamlined fairing – on Hurricane I, L1750, which was subsequently allocated to No. 151 Squadron at North Weald during the Battle of Britain. However, the Hurricane’s thicker wing section allowed for a more reliable and less drag-inducing installation to be made and together with small changes to the feed mechanism and cannon mountings, four 20mm Hispano II cannon, two per wing, were successfully fitted, although the additional weight did reduce performance. Small clearance blisters were also needed on the upper wing surfaces to clear the cannon breeches and feed motors, and the first sets of 20mm-armed wings were modified on the production line from standard Mk.I (eight gun) wings and fitted to the Hurricane IIc which first entered squadron service in June 1941.
Following the Battle of Britain, the Hurricane continued in service, and throughout the Blitz of early 1941 it became the principal single-seat night fighter in Fighter Command. From its earliest service days the Hurricane had proved a pleasant aeroplane to operate at night (unlike the Spitfire with its narrow track undercarriage and sensitive controls), and during the Battle of Britain period Hurricanes regularly flew night patrols to supplement those of the night-fighter Blenheim Ifs. As the Luftwaffe’s daylight raids reduced during late September/early October and the nocturnal campaign took precedence, several Hurricane day fighter units converted to night fighter operations.
At this time Britain’s night defences were in a poor state with few suitable aircraft able to successfully operate at night, although Blenheim night fighters were gradually being replaced by the more powerful Beaufighters, albeit in small numbers. Airborne Interception (AI) radar was still in its infancy, so unarmed Douglas Havoc bombers were modified and fitted with a 2,700 million candle-power searchlight, developed and built by GEC, in the nose behind a flat transparent screen with power for the light coming from lead-acid batteries in the bomb bay. The aircraft was guided to enemy aircraft by a mix of ground control and its own on-board AI Mk.IV radar. As the Havoc’s own armament had been removed, the aircraft was accompanied by a pair of Hurricanes, which, when the target was illuminated, would then attack the enemy bomber and shoot it down.
These composite Turbinlite squadrons, which had been created out of desperation rather than with any real hope of success, achieved little, and, with the rapid development of AI radar and the introduction of the Mosquito night fighter, this wasteful and fruitless experiment was finally abandoned in late 1942.
Twelve Hurricane IIcs were equipped with pilot-operated AI Mk.VI radar in 1942, but after a brief operational deployment with Nos.245 and 247 Squadrons, during which they proved too slow to serve in Europe, they were sent to India in May 1943 and served with No.76 Squadron in the defence of Calcutta until their withdrawal at the end of December.
As well as Night Fighting duties, the Hurricane became increasingly used as an intruder. Following the Battle of Britain, it had been decided to take the fight back to the enemy and raids were launched into occupied Europe, known as ‘Circuses’ – small bombing raids against ‘fringe’ targets escorted by fighters designed to bring the Luftwaffe to battle, or ‘Rhubarbs’ – small scale raids by pairs of fighters or fighter-bombers against targets of opportunity. Neither were particularly effective and RAF losses rose for little tangible return, other than the feeling that the RAF was striking back.
By the beginning of 1941, it was becoming apparent that the development potential of the basic Hurricane design would soon be overshadowed by the new-technology generation of metal monocoque fuselage, thin-wing fighters then being developed.
Although the Hurricane began the year still employed as a day fighter, its days in that role, at least in the European Theatre of Operations (ETO) were numbered, and by the end of the year with the appearance of the Mk.IIb and Mk.IIc, the Hurricane went over entirely to the night, and day, intruder role. Many of the Hurricane night fighter squadrons were now regularly operating over Luftwaffe bomber bases in northern France and the Low Countries and during the last six months of 1941 they claimed the destruction of over fifty enemy aircraft, sixteen coastal vessels, 105 road vehicles and seventeen locomotives. Differing little from their daytime counterparts, other than in their black RDM2 Special Night camouflage, these specialist night intruder Hurricanes were simply fitted with anti-glare shields between the exhaust manifolds and the pilot’s windscreen.
The Hurricane’s ability to carry underwing loads was also exploited. Using the attachment points for 44-gallon long-range auxiliary fuel tanks, as used on the ferry flights to the Middle East, Hurricane I, P2989, was tested at Boscombe Down, Wiltshire, in April 1941, to carry a 250lb bomb under each wing using a standard Type 2 universal carrier covered by a canoe-shaped streamlined fairing. The trials were successful and production of the twelve-gun Hurricane IIb was thus cleared to include the optional underwing bomb rack fitting. Further trials, this time with a Merlin XX-engined Hurricane IIb, were undertaken which allowed for the carriage of a pair of 500lb bombs (although due to the weight penalty this didn’t become a standard operational load), and saw the type move in to the daylight ground-attack role with several squadrons. Despite ostensibly possessing a twelve-gun battery, two of the Mk.IIb’s guns had to be removed (one from each four-gun battery) as each bomb rack obscured one of the middle underwing cartridge case ejector chutes.
Operations with bomb-carrying Hurricane IIbs began in the late autumn of 1941 – presumably cannon-armed Mk.IIcs were deemed destructive enough, although the weight of four cannon and two 250lb bombs would have been even more detrimental to the Hurricanes’ performance in the skies over Europe
Eight Hurricane squadrons took part in Operation Jubilee (the combined forces attack on Dieppe on 19 August 1942), six with bomb-carrying Mk.IIbs, while two, Nos.3 and 87 Squadrons employed cannonarmed Mk.IIcs. Jubilee turned out to be the last major operation involving Hurricanes in any numbers in the Northern ETO. Bomb-carrying Hurricane IIbs continued to operate over Europe on nuisance and intruder sorties until late 1942/early 1943 when they were either replaced by the Hawker Typhoon, or re-equipped with the last Mark of Hurricane, the Mk.IV, armed with 40mm cannon and/or rockets for a relatively brief period during the summer and autumn of 1943 before they too were re-equipped with Typhoons, in time for D-Day.
The Vickers Class ‘S’ 40mm gun was developed in the late 1930s as an aircraft weapon, albeit intended for bomber defence and tested as such in a turret fitted to a modified Vickers Wellington II. In the event it wasn’t adopted for bombers, however, once trials at Boscombe Down in September 1941 with Hurricane IIb Z2326 proved successful, it was adopted as an airborne anti-tank gun with special armour-piercing ammunition. Rolls-Royce also developed a 40mm gun, but it never served as an airborne weapon.
The first squadron to be equipped with Hurricanes fitted with two Vickers 40mm guns, mounted one beneath each wing in conformal fairings, was No.6 Squadron, in the Western Desert in June 1942 where they achieved considerable success, although they also suffered heavy losses, mainly to ground fire. The designation applied to these 40mm gun-armed Hurricanes was Mk.IId – basically a modified 1,280hp Merlin XXII-powered Hurricane IIc with the 20mm cannon removed. A pair of wing-mounted .303 inch mgs were installed – used primarily for ranging and sighting purposes, but also to keep the heads of enemy gunners down – and shackles fitted to take the 40mm gun packs. At least three UK-based squadrons operated the type, No.184 being the first, forming at Colerne, Wiltshire, in December 1942, and Nos.137 and 164 Squadrons, which were only partially equipped with the sub-type in 1943, pending receipt of the ‘multi-role’ Hurricane IV.
Number 20 squadron, based in the Far East, re-equipped with the Mk.IV in May 1943, equipped with 40mm cannon firing high explosive (HE) ammunition against road and river transports. Tests (undertaken in the Far East) showed a high level of accuracy for the weapon, with an average of 25% of shots fired at tanks striking the target. Attacks with HE were twice as accurate as with Armour Piercing (AP) rounds, possibly because the ballistics were a closer match to the .303 inch mgs used for sighting (the HE shell was lighter and was fired at a higher velocity). By comparison, the practice strike rate of the 60lb rocket projectiles (RP) was only 5% against tank-sized targets.
A new universal wing was developed for the Hurricane, which had the ability to take various loads such as the 40mm gun, up to two 500lb bombs, Smoke Laying Canisters and Rocket Projectiles. The fitting of a more powerful 1,620hp Merlin 24 or 27 engine, and an additional 350lb of armour plate, resulted in a slightly re-shaped underside radiator housing. Initially designated as the Hurricane IIe, it was quickly changed to become the Hurricane IV.
As early as October 1941, experiments with RPs had been undertaken, and whilst initially not as accurate as the 40mm gun – that is until the pilots learned how to use the rockets and developed their skills and tactics with them – the effect of a salvo of eight 60lb warhead RPs could be devastating.
Following a rocket-firing course at No.1 School of Specialised Low Attack, at Milfield near Berwick during the spring, and a period of working up and honing their tactics in March 1943, during Exercise Spartan, by mid-June 1943, No.184 Squadron, then based at Manston, Kent, commenced rocket attacks with their newly delivered Hurricane IVs against enemy shipping in the Flushing Straits. Number 184 Squadron was subsequently joined by Nos.137 and 164 Squadrons, following their own rocket-firing courses, during the summer as part of the Channel Stop operations. Other UK-based Mk.IV-equipped units included No.186 (RAF), and Nos.438, 439 and 440 (RCAF) Squadrons, which were operational on this type for varying lengths of time, mainly short periods, before being re-equipped with Typhoons.
Despite the devastation that a salvo of RPs could inflict, the weapon was initially restricted and was not allowed to be taken over enemy territory, so, for the overland ‘Rhubards’, 40mm cannon were carried whilst the rockets were used for attacks on shipping.
The Hurricane IV was withdrawn from frontline operational use in the ETO in March 1944, but Nos.6 (RAF) and 351 (Yugoslavian) Squadrons continued operating the Mark in Italy and Yugoslavia until after the end of the Second World War, as did No.42 Squadron in Burma.