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Aircraft of the Royal Air Force


There is, without a doubt, that the SupermarineSpitfire was one of the most famous of all World War Two aircraft. It wasglamorized by the media, and children young and old would look up towardsthe skies watching a dogfight or see a squadron of RAF fighters come swarmingin towards a formation of German bombers. They would hardly know one aircraftfrom another, but they would all include a Spitfire in their exclamations."It's a Spitfire" or "D'yer see that Spitfire shoot that bomber down, weeeeeooooooow".

But the Spitfire that we knew at the endof the war was far different from the version that flew in the Battle ofBritain and even to that of pre 1939 Spitfires. At wars end, the SupermarineSpitfire was a streamlined fighting machine, it was the mainstay of FighterCommand, but let us not take anything away from the Hurricane which initself was a superb aircraft.

Supermarine gained their experience infast and maneuverable aircraft with experience gained in winning the SchneiderTrophy Air Races. But the concept of the Spitfire really began way backin 1930 when Supermarine submitted their design (Westland and BlackburnAircraft Companies also submitted designs) in relation for the constructionof an all metal type fighter aircraft that would have a fabric coveredwing area as well as tailplane sections. This was to comply with specificationF.7/30.

The wings were of gull wing design, thefixed undercarriage had streamlined fairings over the wheels, and it waspowered by a single Rolls Royce Goshawk engine which provided just 600horsepower giving the Type 224 a top speed of only 228 miles per hour (367kph).  Armament was two .303 guns in the fuselage and one in eachof the wheel fairings. The 224 first took to the air on 19th February 1934,and because of its poor performance it failed to be accepted as a potentialfighter aircraft. Supermarine had great plans for the Type 224, but becauseof its failure in every department, the company had to do something quickto be able to prove to the authorities that they were capable of producinga good hard working fighter aircraft.

THE TYPE 300 - SPITFIRE MK I - SPITFIREMK II - SPITFIRE MK III

Supermarine had for some time enjoyedsuccess in aircraft design and with many aircraft bearing similaritiesto the Schneider successes including the 224, something different had tobe designed. Sydney Camm was now in the process of designing the Hurricaneat Hawker's works at Weybridge. Naturally Supermarine knew of this andit soon became apparent as to the design and the potential of the Hurricane.

Reginald Mitchell set about in designinga completely new type of aircraft. They stayed with the required specificationsas called by F.7/30 in producing a metal bodied cantilever type fighteraircraft. Mitchell decided that the wings should be metal as well as thefuselage believing that fabric covered wings on an aircraft with a metalbody at high speed would provide the aircraft with weak spots. The cockpitof the aircraft was enclosed and formed part of the design lines of thebody, while the narrow undercarriage was retractable with the wheel beinglifted into wheel wells under the wings.

The design was a streamlined, yet strong,an  aircraft that had all areas that would cause any form of resistanceto wind removed. It was claimed, as the aircraft made its early test flightsthat not only did this Type 300 look exciting it was yet the most attractiveaircraft ever designed.

By the end of 1934 the Type 300 was eventually ordered as a prototype, andfurther testing was done and it was put through a series of strenuous tests.By 1935, the aircraft with its Rolls Royce PV12 now glycol cooled engine(this engine was later to be known as the Merlin), and four .303 Browningmachine guns in each wing gave a performance good, or maybe even betterthan expected.

The aircraft flew on official tests inMarch 1936, and by June of the same year, and by now the name Type 300had been dropped and the name Spitfire had been officially adopted, theaircraft went into production as Spitfire Mk I. Already Rolls Royce hadreworked the Merlin power unit and the Merlin II and III had the poweroutput increased to 1,000 hp. The basic design was a 12 cylinder unit inV formation. The first Spitfire I's began flying on May 14th 1938 withthe first of them going into service use by the RAF in August.
Flyingthe Spitfire was like driving a sports car. It was faster than the oldHurricane , much more delicate. You couldn't roll it very fast, but youcould make it go up and down much easier. A perfect lady. It wouldn't doanything wrong. The Hurricane would drop a wing if you stalled it comingin, but a Spitfire would come wafting down. You couldn't snap it into aspin. Beautiful to fly, although very stiff on the ailerons - you had tojam your elbow against the side to get the leverage to move them. And sofast!!! If you shut the throttle in a Hurricane you'd come to a grindinghalt; in a Spitfire you just go whistling on.
[1] P/OH.G.Niven 601 & 602 Squadrons, having flown both Hurricane and Spitfire.

Spitfire Mk I's remained until June 1940,but until then, thirty of them had been equipped with twin 20mm cannonsat the expense of the .303 Brownings. To distinguish the two, the SpitfireMk I's equipped with machine guns were designated IA's, while those thathad the cannons fitted were designated IB's. In all, 1,537 Spitfire MkIA's were built and 30 Spitfire Mk IB's. The Spitfire IB's were not favouredwith pilots, the cannons were often jamming leaving them a defencelessaircraft and pilots requested to be returned to the Spitfire IA's.

At the outbreak of the Second World War, the Mk I's were the mainstay of Fighter Command along with the Hurricane. When air support was needed in Norway and in France, Fighter Command sent only one squadron to Norway and ten to France. By this time Britain had lost some 500 fighters in thisearly part of the war. The Mk I Spitfire was to continue service throughout the Battle of Britain, and was a worthy opponent of its German equivalent, the Messerschmitt Me 109. But in August 1940, at the height of the battle, the Spitfire Mk I gave way to a faster and more powerful Mk II with its Merlin Mk XII power plant. Most of these MK II's were to arrive after the Battle of Britain, although some squadrons had been allocated them in late August and during September 1940. The first recorded Mk II being shot down was with 611 Squadron on September 11th 1940.

By now, the Supermarine Spitfire, withnot only the specifications, but as further testing of the aircraft proved,was a fighter aircraft that was superior in every department to anythingthat was flying at the time. Sleek and swift, maneuverable, strong andwell constructed.

The Merlin engine had received a powerincrease to 1,175 horsepower and was designated the Merlin XII. The differentiatingversions of A's and B's continued and production of these totaled 751 MkIIA's and 170 Mk IIB's.

The Spitfire Mk III, also introduced in1940, but not allocated to operational service until 1941, while still cosmetically looking like a Spitfire, it had a greaterimprovement in airframe construction and also had a reduced wing span.Again, improvements had been made to the Merlin XII engine and was redesignatedthe Merlin XX, and the tail wheel was also made to retract into the fuselage.When it seemed that the Mk III was almost at its best, and in July 1940it was intended to build 1,000 of them, but a slightly redesigned version,a prototype Mk V was under way and testing was being done on a four cannonarrangement. Because of this, the target of 1,000 Mk III's was never reached.


Supermarine Spitfire Mk IA Specifications
 Type Monoplane
 Military Use Front Line Fighter
 Power Plant Rolls Royce Merlin II
 Horsepower 1,175 hp
 Maximum Speed 355 mph
 Climbing Rate 0 -20,000ft/9.04min
 Working Range 575 miles.
 Empty Weight 5,067 lbs
 Loaded Weight 6,409 lbs
 Service Ceiling 34,000 feet
 Wingspan 36 ft 10 in (11.23m)
 Overall length 29 ft 11 in
 Overall height 11 ft 5 in
 Total Wing Area 242 sq ft
 Armament 8 x .303 Browning machine guns

We should note here that there were three versions of Mark I Spitfire. The Mark I was provided with only four .303 Browning machine guns, and although all Series I aircraft did not have armour plating protection fitted during production, this was added to the aircraft whilst it was in service. The Mark IA varied only slightly to the Mark I, in that it had eight .303 Browning machine guns, four in each wing. The Mark IB reverted back to four .303 Browning machine guns, but with the addition of a 20mm cannon.

The Mark II differed from all the Series I Marks by having the Merlin II engine upgraded to the more powerful Merlin XII. Armour plating was now fitted on the production line as standard, and like the Series I Spitfires, there were those fitted with eight .303 browning machine guns designated as Mk IIA and others fitted with four .303 Brownings and a 20mm Hispano cannon. Although the first Mk II Spitfires were delivered to the RAF on June 3rd 1940, there were still more Mk Is produced than the Mk IIs. In fact the comparison figure was 1,531 to 920.
Specifications and notes taken from THE NARROW MARGIN by Wood & Dempster.



SPITFIRE MK V - SPITFIRE MK VI
Supermarine went back to the Mk I airframefor the prototype Mk V and and installed a more potent Merlin 45 enginethat although rated at 1,185 horsepower, its combat rating at 9,250 ftwas actually 1,470 hp. The Merlin 45 engine was also installed into theMk II airframe and in total 150 of these were made and became known asMk V conversions. The designated Spitfire Mk V as well as boasting the1,185hp Merlin 45 engine, had either eight .303 machine guns, four in eachwing, these were Mk VA's and only 94 were built. The MK VB was equippedwith four .303 machine guns, two in each wing and two 20mm cannons, and3,911 of these were built. The Mk V also saw the introduction of the series"C", and the Spitfire MK VC had four cannons with four machine guns andthese totaled 2,467 aircraft.

The first prototype MK V flew in December1940 and MK VA's were placed in service almost immediately. The MK VB sawservice in March 1941, (I have no record as to when the MK VC enteredservice).

Many versions of the MK V followed, dependingas to which field of conflict the aircraft were assigned to. Some wereassigned to low altitude flying and for this many of the MK VB's had theirwing span reduced to 32 feet 2 inches and the Merlin 45 engine was replacedby the Merlin 45M, the Merlin 50M and the Merlin 55M, all of which performedbetter at low altitudes. These low altitude versions were designated LFMK VB's. Other versions included the medium altitude Mk's. These aircraftwere designated F MK VA, F MK VB and F MK VC. The Merlin power plant wasconfigured in a number of configurations and all these F series MK V'shas either a Merlin 45, 46, 50, 50A or 56 engine installed. All these MKV's became successful fighter aircraft.

First deliveries of Spitfires with majorchanges took place in February 1942 when the Spitfire MK VI was introduced.The MK VI received the all new Merlin 47 engine that was rated at 1, 415hp providing the aircraft with a top speed of 374 mph and the pilot cockpitwas now pressurised. This MK VI also had an increase in wing span beingincreased to 40 feet 2 inches.

THE SPITFIRE AT SEA
Contrary to the belief of many, the Hurricaneand Gladiator was not the only fighter to be equipped with facilities tooperate from the Navy's aircraft carriers. The Spitfire also served fromthese floating bases during WWII.

The admiralty saw the potential of theSpitfire, and requested that a version be designed that could operate fromits aircraft carriers. The request was granted and designs were made fora Sea Spitfire. As early as 1940, designs were being submitted based onthe Spitfire MK I which would have an arrestor hook and folding wings sothat it could be stored in aircraft carrier hangers below deck. But in1940 there was a shortage of fighter aircraft during both the Battle ofFrance and the Battle of Britain that supply of Spitfire Mk I's to theRAF took precedence over the Admiralty's request hence supply of Spitfiresto the Navy did not commence until early 1942. The first Spitfire to flywith arrestor hook and folding wings did not take place until January 1942when a modified MK VB made tests with the Navy. A further conversion tookplace that provided the aircraft with catapult spools and the undercarriagewas given additional strengthening, and an A frame type of arrestor hookwas incorporated.

It was not until about March 1942 thatthis naval version of the Spitfire was given the name of Seafire. The firstconversion was known as the Seafire MK I and the second conversion wasknown as the Seafire MK II. The Royal Navy was supplied with 165 Seafire'sduring the early part of 1942 which were based on the Spitfire VB.

InJune 1942, 375 Seafire MK IIC's were supplied to the Royal Navy. thesewhere basically Spitfire MK VC's and given the same conversions as theMK II with the exception that the Merlin 32 engine drove a four bladedpropeller which improved low altitude flying. In the November of 1942 aSeafire MK IIC was altered so that the wings could be folded for storageon aircraft carriers, this was to be a prototype for the proposed MK III.Manufacture of the Seafire MK III was given to both the Westland AircraftCompany and Cunliffe-Own Ltd, which now also boasted a powerful 1,470 hpMerlin 55. 1,263 of these MK III were made all being used by Britain'sNavy by June 1943. Many of these MK III's also had the Merlin 55M enginesthat had increased horsepower to 1,585. Other than these aircraft, there were manymore Spitfires and Seafires produced. Each one being produced for its ownindividual reason to that it would perform well to the task that it wasdesigned for. These Models included:


MODEL
DATE
POWER
NOTES
SpitfireIXJuly1942Merlin61 S/Charged
5,656 units were produced.Max fighting ceiling was increased by 10,000 feet and max speed had beenincreased to 410 mph.
SpitfireXVIOctober1944PackardMerlin 266
1,054 units were produced.New rudder and cut down rear fuselage. Two 20mm fitted to outer wing baysand two .5 machine guns to wing inner bays in 1945.
SpitfireVIISept1942Merlin64 (1,710hp)
This version was primarilydeveloped a s a high altitude fighter. Fitted with pressurised cockpit.Only 140 were produced.
SpitfireVIII 
F Mk VIII 
LF Mk VIII 
HF Mk VIII
July1943Merlin63 (1,710hp) 
Merlin 61 (1,565hp) 
Merlin 66 (1,705hp) 
Merlin 70 (1,655hp)
1,658 units were produced.Developed as a general purpose fighter. Many variants were made using avariety of Merlin engines. These can be read in both columns 1 and 3. Mostof these aircraft saw service in the Middle East.
SpitfireXIILate1943GriffonIIB (1735hp)
Once known as the Mk IVand first prototypes ordered as early as 1940, and used the Rolls RoyceGriffon engines. 750 were originally ordered, but develop- ment was slowand did not fly till Nov 1941. Saw service in 1943 and only 100 built.Changed to Mk XX
SpitfireXIVJanuary1944Griffon65 (2035hp)
957 units were built. Longernose, large radiators and vertical tail, this two stage supercharged Griffonengine with 5-bladed propellers gave the XIV a top speed of 450mph. Twocannon and four .303 machine guns as armament.
SpitfireXVIIIJune1945Griffon65 (2035hp)
Very similar to the XIV,but having lengthened fuselage, more vertical tail, increased fuel capacityand strengthened wings. Only 300 built.
Spitfire21April1945Griffon64 (2375hp)
First prototype early as1942, was to have been the second prototype IV, New wing design and ailerons.Called the Victor for a time. Carried 4 x 20mm cannons, wider undercarriagetrack extra fuel capacity.
120 units were produced.
Spitfire22  
Spitfire 24
April1946 to 
March 1948
Griffon64 (2375hp)
The 21 suffered handlingproblems, and the introduction of the 22 fared no better. The lengthenedfuselage had now been reduced as before, a rear view hood was fitted, andmore modern electric were installed. 287 were produced, but were discontinued in favour of the Prototype24. This had two extra fuel tanks in the rear fuselage, larger tail fin,and improved laminar flow on the wings. The Type 24 proved to be a Spitfirethat had reached its absolute perfection. 
No more Spitfires were producedafter this.

Supermarine further developed the Seafirewith types 45, 46 and 47. Fitted with the Rolls Royce Griffon 61 whichproduced 2,035hp giving the Seafire a top speed of 455 mph. The type 46was fitted with an all round vision bubble canopy. Like the Spitfire, theSeafire had reached its peak and was the ultimate Seafire. It continuedservice with the Royal Navy finally curtailing its long career during theKorean War. One of the few aircraft that still bearing its original designsaw service in two wars.

But the story of Spitfire does not endthere. In 1942, under specification request F.1/43, another aircraft wasdesigned based on similar lines to the Spitfire. The experience gainedin the Spitfire's production was used in the new design of the Type 371.But because of Spitfire production, it was two years before 371 saw itsfirst flight. At the commencement of production the aircraft was designatedthe Supermarine Spiteful. It used the same fuselage as the Spitfire, alonger nose to enclose the Griffon 61 engine with two stage supercharger,completely redesigned wings that were very unSpitfire, a bubble canopyand larger tail fin.

In January 1945, a second prototype includeda five bladed propeller, slimmer fuselage and the Griffon 61 engine wasreplaced with the 2,375hp Griffon 69. Top speed of the Spiteful was a staggering486 mph, and it would climb to 20,000 feet in just 4.9 minutes. Only about20 were built with just 16 of them taking to the air. This was due to thefact that at the end of the war, the jet engine was making an impact inaircraft manufacture, and even Supermarine was busy designing its firstjet aircraft the Attacker in 1944.

But in 1945, Supermarine was to have onelast attempt at producing a piston engined propeller driven aircraft. Thiswas the Seafang, a naval version of the Spiteful. Specifications were similarto the Spiteful with the exception that fittings that would make it destinedfor naval operations were included. After this, Supermarine was to enterthe jet age and, Reginald Mitchells Spitfire will go down in the annalsof modern history as one of the exciting and successful fighter aircraftof the Second World War.

Picture at top:
Spitfire IIA with the markings from 41Squadron Hornchurch.

[1]Christopher Sommerville Our War Weidenfeld & Nicolson 1998 p47



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