The Hurricane
Design of the Hurricane had begun in 1934,
and its first flight had been made, from Hawker's establishment within the
confines of the historic Brooklands motor racing circuit at Weybridge in
Surrey, on November 6, 1935. Sydney Camm's design team at nearby Kingston upon
Thames already had long experience of fighter design for the RAF, and drew
heavily upon this experience to produce what was at first seen as a "Monoplane
Fury" -- the Fury being the elegant biplane that still epitomized the
equipment of Fighter Command upon its formation within the RAF in, July 1936,
Such advanced features as an enclosed cockpit and retractable undercarriage
were combined with traditional methods of construction using a tubular metal
structure and fabric covering, that meant that the Hurricane could be easily
and rapidly produced in existing facilities -- an advantage not enjoyed by the
Spitfire with its advanced stressed-skin construction and complex shapes.
In February 1936, the prototype Hurricane
(as yet unnamed), powered by an early Merlin C producing 900hp and driving a
Watts fixed-pitch two-bladed wooden propeller, was tested at the Aircraft and
Armament Experimental Establishment (A & AEE) at Martlesham Heath, giving
Service pilots their first opportunity to experience the improvements in
performance and handling that were to become available.
At a weight of 5,6721b (2,572kg), the
prototype demonstrated a speed of 315mph (506km/h) at the Merlin's rated
altitude of 16,200ft (4, 937m)with 61b/sq in boost, After taking off into a
5mph (8km/h) wind with a run of 795ft (242m) to reach the 81mph (180km/h)
lift-off speed, the Hurricane climbed to 15,000ft (4,570m) in 5.7 minutes and
to 20,000ft (6,100m) in 8.4 min. Service ceiling was 34,500ft (10,515m) and
the estimated absolute ceiling was 35,400ft (10,800m).
Convinced that the RAF would buy the new
fighter in the prevailing mood of rearmament, the Hawker company decided, in
March 1936, to proceed with the production drawings and to make plans for
large scale production. Three months later in July, that action was vindicated
when the Air Ministry confirmed that 600 Hurricanes were to be included in its
expansion Plan F (which also provided for 300 Spitfires). By the time the
Battle of Britain began, every single fighter in the hands of the RAF counted,
and the early launch of Hurricane production had helped to ensure that just
enough machines were in fact available to Fighter Command.
Even so! meeting the RAF's rapidly
expanding needs proved to be no simple matter and the Plan F target of 600
Hurricanes to be delivered bv March 1939 was missed by some six months. There
had been a succession of relatively minor but time consuming problems with
prototype development, especially related to the Merlin, and the early
intention to fit the Merlin F (Mk I) in the production Hurricane was changed
to make use of the improved Merlin G; (Mk II)- which required a redesign of
the installation and the front fuselage profile before production could begin.
The cockpit canopy also produced its share of problems, with five failures
recorded on the prototype before a satisfactory design was evolved.
The first production Hurricane I flew at
Brooklands on October 12th 1937, fitted with an early example of the Rolls
Royce Merlin II that was rated at 1.030 hp at 16,250 feet (4,955m). This power
unit drove a fixed pitch two bladed propellor and at a weight of 5,459lb
(2,476kg) the aircraft attained a maximum speed of 318 mph (512 kph) at 17,400
feet (5,305m).
In January 1939, the Merlin II gave way to
the Merlin III and with the fitting of a constant speed three bladed propellor
and it was this amended specifications that was adopted and all Hurricane Mark
I's were constructed using this configuration. Other alterations/additions
being the armament which was four Browning .303 machine guns mounted in the
wings, metal stressed- skin covered the wings instead of fabric which also
covered the fuselage.
By the 27th September 1939, Hawker had
delivered 497 Hurricanes to the RAF against the initial order of 3,500 and was
enough to equip 18 Fighter Command squadrons. But despite the need to bring
Britain's fighter strength to its potential, quite a number of Hurricanes were
exported to other countries. 15 went to Turkey, another 15 went to Finland, 12
went to Romania while 1 went to Poland.
During late 1939 and early 1940, 1,924
Hurricanes had been constructed by the Hawker works while Gloster Aircraft who
also took on construction built 1,850. Hawker also put out tenders for the
construction of the Hurricane overseas. One of these successful tenderer's was
the Canadian Car and Foundry Works (CCF) and a licence was issued for the
construction of both the Hurricane and the Sea Hurricane. A total of 1,451
machines were built and of these, 60 were flying by 10th January 1940. The
Canadian company built the Hurricane in a number of different versions. The
original accepted design of the Mark I, the Mark X which were powered by the
Merlin 28 engine and built by the Packard Car Co, the Mark XI which was built
with Canadian equipment and the Mark XII's that now incorporated the Merlin 29
engine and 12 Browning guns. (8 guns in the Mark XIIA).
Because of the weather conditions in Canada
and especially Nova Scotia where many of them were based, the normal
retractable undercarriage was dispensed with and fixed ski's were used in
there place. This allowed the aircraft to take off and land on snow and ice.
During 1939 and 1940, 24 Hurricane Mark I's
were delivered to Yugoslavia, and Belgium was also granted a licence to build
the fighter although 20 had been acquired from Britain only 15 of these had
been delivered.
Hurricane Mark II
through to Mark V
June 11th 1940 a Hurricane Mark I was
fitted with a two stage supercharged Rolls Royce Merlin XX engine that at sea
level was rated at 1,300hp rising to 1,460hp at 6,250 feet. After numerous
tests the aircraft was given the designation of Mark II, the improved power
plant being the only difference from the Mark I. This first model of the MkII
was known as the Series I. Further modifications took place as designers tried
to make improvements to the Hurricane. The next model was given the title of
Mark II Series 2. The fuselage was given added strengthening which was needed
to accommodate the redesigned wings that incorporated attachment points for
external stores. A bay was also introduced into the fuselage that also
increased the length by a additional 7 inches (7.7mm).
In November 1940, the Mark II Series 2 was
given additional firepower by the inclusion of 12 .303 machine guns mounted in
the wings. This version was known as the Hurricane IIB. The Hurricane IIC
followed by having four 20mm Hispano cannons also mounted in the wings.
Many of these versions flew during the Battle of Britain with a number of Mark
II's being fitted with drop-tanks, some being fitted with light to medium
bombs while other had increased stores such as additional room for bullets for
the machine guns.
After the Battle of Britain, the Hurricane
was further developed, mostly up to and including 1942 even though it was
relieved as a front line attack aircraft in the air to air war, and was used
mainly as a ground attack aircraft. The Mark IIC served until June 1942 when
the Hurricane IID appeared which was basically a IIC but with two 40mm cannons
and two .303 machine guns.
The Hurricane II gave way to the Hurricane
III with a Packard Merlin power plant, then came the Hurricane IV, the first
prototype flying on 14th March 1943 which had been previously known as the
Hurricane IIE, but after the designation change was fitted with reinforced
under wing attachments to carry bombs and rockets and was given the new Merlin
24 engines that put out 1,620hp. A further alteration saw the Mk V which was a
Mk IV but given even more power by the fitting of the 1,700hp Merlin 32
engines and having four bladed propellors.
In all, 8,406 Hurricane II's were produced,
with 3,000 going to the Soviet Union. In all, only 794 Hurricane IV's were
made.