Versions of the Supermarine Spitfire
The Supermarine Spitfire was a British interceptor. Information about the Spitfire itself can be found on the Supermarine Spitfire page .
There were a total of 24 main versions and many sub-versions. This article is a brief history. The last series not yet described here had, among other things, more powerful Rolls-Royce Griffon engines and longer suspension struts. The last version F. 24 flew at the end of the 1940s, among others with RAF Germany and during the Korean War with No. 80 Squadron in Hong Kong. However, the machine no longer flew combat missions there.
Versions
Note: “Mark” (abbreviated “Mk” or “Mk.”) Means something like “version” or “variant” in German. Roman numerals were initially used to number the versions, and since 1948 Arabic numerals (as part of a changeover across the entire Royal Air Force). See also variant _and_use IDs of the British Air Force .
Mk I
It quickly became clear that the new design would be the best British fighter at the time; In contrast to its competitor Hawker Hurricane , the Spitfire seemed to have enough room for improvement. At Vickers it quickly became clear that the first order of 310 aircraft was only the beginning of a long series, so in addition to the existing production lines in Woolston, a new factory was built near Castle Bromwich to manufacture Spitfires there.
In 1938, their thinking ahead paid off when the Aviation Ministry ordered 1,000 additional Spitfires. In 1939, orders for 200 and 450 units respectively followed before the outbreak of war. At the beginning of the Second World War , a total of 2,160 Spitfires had been ordered or had already been delivered.
The Woolston factory began series production of the Spitfire Version 1 (Mk I) in late 1937. From August 1938 the first squadrons of the Royal Air Force were operational. The Mk I was originally powered by a Merlin Mk-II engine with 1,030 horsepower that worked on a two-bladed wooden propeller with a fixed angle of attack. In this configuration, however, only 77 copies were delivered, after which a three-bladed metal variable pitch propeller from de Havilland was installed, which could be switched between two different propeller pitches. Although the weight of the propeller increased from 41.5 kg to 175 kg, there was an increase in performance. The taxiing distance at the start decreased from 382 m to 291 m. At an altitude of 6,000 m, the top speed increased from 577 km / h to 584 km / h. The service ceiling rose from 9400 m to 10450 m. Just before the Battle of Britain began , another three-bladed propeller was introduced. This was continuously adjustable and worked at a constant speed. There were two different types of Rotol and de Havilland. The weight of the new propeller was 250 kg. The taxiing distance at the start decreased to 205 m.
At the beginning of the war, only a few RAF units were equipped with the Spitfire. While the hurricane was deployed over continental Europe, the more powerful Spitfires were held back by the chief of British Fighter Command , Hugh Dowding , for the impending defense of England. By the beginning of the Battle of Britain in July 1940, the supply situation had improved so much that 19 squadrons now had Spitfires and 27 Hurricanes. By the time the Battle of Britain was fought in October, the RAF had lost 565 Hurricanes and 352 Spitfires.
In the meantime, however, the British factories had reached their maximum production output and the material losses could be replaced quite easily (the pilots, however, not). The production of the Hurricane as a front fighter was shut down in favor of the Spitfire. In Season 19, several cannon-armed Spitfires known as Mk IB were tested during the battle. The destructive power of the cannons was valued, but the guns suffered from jamming so often that the IB was pulled out of combat and the 19th Squadron was again equipped with machine-gun-armed Spitfires at its own request. A total of 1,583 of the 2,160 Mk I ordered were delivered before production was switched to the new Mk II version.
Mk II
With the end of the Battle of Britain, the Royal Air Force gained a respite over the winter of 1940/41. This break in combat was used to integrate various improvements identified as necessary during the fighting into the Spitfire - the result was the Type 329 Spitfire Mk II .
The biggest change was the more powerful Merlin XII engine with 1,175 hp. The additional engine power increased the top speed by 28 km / h and improved the rate of climb somewhat. It would have been even better if the Spitfire Mk II hadn't been given 32 kilograms of additional armor plates around the cockpit.
The Mk II was produced in the versions IIA (with eight machine guns) and (more rarely) IIB (two cannons / four machine guns). The delivery took place very quickly and the Mk II gradually replaced all Mk I still in service, which from then on were used for pilot training. By April 1941, all RAF Spitfire squadrons had been converted to the new model, a total of 920 units were built.
Mk III
The two Mk IIIs, which were built as test aircraft, represented the first comprehensive redesign of the original Spitfire airframe. Series production was not planned. The aircraft received the new Merlin XX engine with two-speed charger , which should enable the Spitfire to achieve a higher horizontal speed at great heights. However, the Merlin XX was very complex and difficult to produce, mainly because of its loader. At the same time, the performance of the Hawker Hurricane had to be increased in order to maintain it as a viable front-line fighter. It was therefore given priority with regard to the Merlin XX engine and became the Hurricane Mk II. The two test machines received the RAF serial numbers N3297 and DP845. The DP845 went through various equipment and cell construction phases during its existence. This aircraft was used successively as a prototype for the Mk. IV, Mk. XX and Mk. XII variants.
Mk IV
The Mk. IV was an intermediate stage of the DP845 originally built as the Mk. III. It received the new Griffon IIB with a four-blade metal propeller with a capacity of over 1500 hp . This extra performance increased the top speed to over 420 knots. Attempts with the aim of installing an armament of six 20 mm cannons probably only led to implementation in dummy form. The Spitfire 21 and 22 later emerged from this first Griffon variant.
PR Mk IV
After the original Mk IV was renamed, the unarmed long-range reconnaissance aircraft Mk I PR Type D was renamed the PR Mk IV. Of these, 244 machines were made.
Mk V
At the end of 1940 the Mk II met a new German aircraft. It was an improved version of the Messerschmitt Bf 109 . The new Bf 109F model surpassed the Spitfire II in terms of speed and rate of climb and, above 5,500 meters, also in terms of maneuverability.
At this point the Mk IV was not ready to face the new Bf 109F. The Griffon engine suffered from such severe production problems that it was unclear whether it could even go into series production. The Mk V was therefore designed as an emergency solution.
The Mk V combined the airframe of the Mk II with the newer Merlin 45 engine. This engine developed a slightly higher take-off power of 1,440 hp, but increased the available power at a slightly higher level thanks to its improved engine charging .
The Mk V was by far the most produced version, with 94 Mk VA (eight MG), 3,923 Mk VB (two cannons and four MG) and 2,447 Mk VC (four cannons or two cannons and four MG, modified ammunition feed, thus ammunition supply of the cannons increased from 60 to 120 rounds per barrel).
Mk VI
While the Mk V was in production, fears grew that the German Air Force could increasingly use very high-flying bombers such as the Junkers Ju 86 , whose peak altitude was higher than that of most fighter planes of the time. It was decided to develop a new Spitfire variant with an improved service ceiling.
The Mk VI showed two important improvements in this direction. For increased performance at greater heights, it had a four-bladed propeller. In order to counter the physiological problems that pilots are exposed to at high altitudes, it was equipped with a pressurized cabin that enabled a pressure difference of 13.8 kPa and thus produced a cabin pressure altitude of 8.5 km at an altitude of 11 km. Despite the pressurized cabin, the pilot had to wear a breathing mask.
The reinforced canopy required for the pressurized cabin on the Mark VI could not be opened during the flight; the pilot could only eject it in an emergency.
Another special feature of the Mk VI were the enlarged, almost pointed wing tips, which improved the altitude performance. They were later used on the Mk VII and some Mk IX.
Mk VII
Like the Mk VI, the Mk VII also had a pressurized cabin. With the new Rolls-Royce Merlin 61 engine , which had a two-stage two-speed high-altitude loader, the Mark VII was the first Spitfire variant to perform well at high altitude. In addition, the Mark VII had a reinforced airframe and small wing tanks. It also had the extended surface ends of the Mk VI.
Mk VIII
The Mk VIII was developed to take full advantage of the additional performance of the 60-series Merlin. It was equipped with numerous aerodynamic improvements such as a retractable tail wheel. Other features included a stronger cell structure, an additional fuselage tank and a different carburetor air inlet with filter. As a result, the Mk VIII was suitable for use in the tropics and was mainly used in Southeast Asia, only a few flew in Europe. Another characteristic was the enlarged rudder, which improved the controllability, especially in slow flight and during take-off and landing.
Most Mk VIII had the normal canopy and C-wings with two cannons and four machine guns. There were versions with normal and shortened wing tips. The Mk VIII did not have a pressurized cabin.
Mk IX
With the appearance of the Fw 190 on the Channel coast, the Mk V suddenly found itself at a significant disadvantage in terms of performance. Since the introduction of the Mk VIII was still a long time coming, an interim solution was needed. The airframe of the Mk V was equipped with the new engines of the Merlin 60 series and the Mk IX was created. In fact, quite a few early Mk IXs were converted from Mk V. Although it was only planned as an interim solution until the introduction of the Mk VIII, far more Mk IXs were produced overall than Mk VIIIs; in terms of the total number of units, only the Mk V exceeded it.
The MkIX was available with the normal, capped and even with the long wing ends of the high altitude fighter, mostly two 20 mm cannons and four .303 machine guns, later also two cannons and two .50 machine guns were installed (so-called E-wings ). Since the Mk IX was produced until the end of the war, it was also subject to constant improvements. For example, the engine's boost pressure was later increased to 25 lbs, which improved the machine's performance at low and medium levels. Some late Mk IXs were built with a full view canopy similar to the Hawker Tempest and the enlarged rudder of the Mk VIII.
Mk XII
First Spitfire variant with Griffon engine with single-stage charger. Excellent fighter for low altitudes; it was used in this capacity against Fw-190 fighter-bombers and V1 aerial bombs . Only 120 pieces were built, some with the retractable tailwheel of the Mk VIII. All Mk XII had the short wing tips and an armament of two 20-mm cannons and four .303-MG. Since the high-altitude performance was limited by the single-stage loader, the Mk XII was replaced relatively quickly by the Mk XIV.
Mk XIV
Similar to the Merlin of the 60s series, the Rolls-Royce Griffon also received the two-stage loader. The Spitfire version equipped with this engine became the Mk XIV. It is considered to be one of the most powerful piston engine fighter aircraft of the Second World War.
Her Rolls-Royce Griffon 65 developed up to 1,514 kW and enabled a top speed of 717 km / h at an altitude of 8,000 m and a peak height of up to 13,600 m. The Mk XIV were used from summer 1944 to fight the German V1 attacks.
A total of about 1,000 machines of different variants went to the squadrons of the RAF. There were versions with normal and short wings, earlier Mk XIVs still had the B armament consisting of two cannons and four MG (in the C wing), later the E wings with two cannons and two .50 MG. Some Mk XIV received an additional oblique camera in the stern and were designated as FR Mk XIV fighter reconnaissance aircraft.
Sources: Munson: World War II Planes. P. 243,
Mark XVI
Like the Spitfire IX, but with the Packard-built 60s-series Merlin. Also here partly full view hood and enlarged rudder.
Mark XVIII
Improved Mark XIV. Identical in many ways to the Mark XIV including engine (Griffon 65) and cockpit. But with additional fuel capacity and a revised, stronger wing structure. Some built as FR Mk XVIII with an additional angled camera in the rear.
Mark XIX
Photo reconnaissance variant based on the Mark XIV. Fastest Spitfire version with the original wings. An Mk XIX also flew the last Spitfire.
F. 21
Spitfire with Griffon engine and newly designed laminar wing . Standard four 20mm cannons. Top speed: 730 km / h, only 120 units built, first use a few days before the end of the war.
F. 22
Analogous to F. 21 but with full view hood; partially retrofitted with Spiteful tail unit. Some aircraft were equipped with Griffon 85 engines (2,373 hp / 1,771 kW) and counter-rotating propellers. 278 Spitfire F. 22 were built.
F. 24
Last version of the Spitfire. Externally identical to MF. 22; Spiteful tail unit as standard. The No. 80 Sqn was the only squadron to receive this pattern and thus belonged to RAF Germany for some time at the end of the 1940s .
Seafire
There were also several marine versions of the Spitfire under the name Seafire , which were provided with catch hooks , foldable wings and other equipment necessary for this task for the use of aircraft carriers . Due to the center of gravity shifted to the rear by the carrier equipment and the narrow-gauge and not particularly stable landing gear, however, they were not very suitable for operations from the flight deck and had a high accident rate. The rather short range also did not meet the requirements for a carrier-supported pattern.