Supermarine Spitfire (Griffon-powered variants)
| Company type | Aircraft piston engine |
|---|---|
| Industry | Aerospace |
| Founded | 1939 |
| Founder | Rolls-Royce Limited |
| Products | Aircraft engines |
| Website | www |
The Rolls-Royce Griffon engine was created to meet the Royal Navy’s demand for a powerplant delivering strong performance at low altitudes. Plans to modify the Supermarine Spitfire to accommodate this new engine were underway as early as October 1939; Joseph Smith believed that "The good big 'un will eventually beat the good little 'un," while Ernest Hives from Rolls-Royce Limited regarded the Griffon as "a second power string for the Spitfire". The initial flight of a Griffon-powered Spitfire took place on 27 November 1941.
Despite never reaching the production volumes of Merlin-powered models, Griffon-engined Spitfires played a significant role within the Spitfire lineage and maintained its status at the cutting edge of piston-engine fighter technology in later iterations. This entry focuses on those Spitfire variants equipped with Griffon engines.
Wing types
From the Mk VIII onwards, most Spitfires were fitted with C, D, or E wing configurations. Unless specified otherwise, all Griffon-powered Spitfire versions featured reinforced Dunlop AH10019 "four spoke" mainwheels. As hard runway surfaces became more common in the post-war period, numerous Spitfires were either built or updated with larger mainwheels sporting a "three spoke" design. These wheels were paired with modified undercarriage legs that incorporated less "toe-in" on the axles, effectively reducing tyre wear due to scrubbing.
C type
Frequently referred to as the "Universal wing," this design became the standard for the majority of Spitfires produced from mid-1942 onwards. The wing structure was revised to streamline manufacturing processes and reduce labor requirements, while accommodating a variety of armament configurations: A type, B type, or four 20 mm Hispano cannon.
The landing gear mountings underwent a redesign, with the undercarriage doors adopting a bowed cross-section that allowed the legs to retract lower into the wells. This change eliminated the upper-wing blisters above the wheel wells and landing gear pivot points. Reinforced undercarriage legs were angled forward by 2 inches (5.08 cm), enhancing ground stability and decreasing the chance of nose-overs. During the production of Mk VIII and Mk IX models, an updated undercarriage leg featuring external v-shaped "scissor-links" at the front was introduced, prompting minor alterations in the shape of the undercarriage bay and leg fairings. Certain Spitfire variants, such as Mk XIV and Mk XVIII, incorporated additional 13-gallon integral fuel tanks within the leading edges of the wings, positioned between the wing root and inboard cannon bay.
The Hispano Mk.II cannons transitioned to belt-fed box magazines capable of holding 120 rounds per gun (rpg), utilizing the Châtellerault system. The fairings over the cannon barrels were shortened, often accompanied by a small rubber cover on the outer cannon ports. Redesigned upper wing gun bay doors featured "teardrop"-shaped blisters to accommodate the cannon feed motors, while heating vents previously located outboard of the lower wing gun bays were removed. To make space for the belt feed mechanism, inner machine gun bays were repositioned outward between ribs 13 and 14. Since these Spitfires were no longer employed as night fighters, retractable landing lights were omitted.
D Type
Designed exclusively for Photo-Reconnaissance Spitfires, including the PR XIX model, these wings lacked any armament installation. The leading edges ahead of the main spar were reshaped with a D-profile to serve as integral fuel tanks, each capable of holding 66 gallons. To prevent damage from fuel expansion during hot weather, pressure relief valves with small external vent pipes were installed near the wingtips.
E type
This wing retained its structural similarity to the C type but eliminated outer machine gun ports while keeping their respective bays intact; access doors no longer featured openings for empty cartridge cases or deflectors. The inner gun bays supported two possible armament layouts:
- Two 20 mm Hispano Mk II cannons with 120 rounds per gun in the outer bays combined with two 0.5-inch (12.7 mm) Browning M2 heavy machine guns carrying 250 rounds per gun in the inner bays. Relocating the Hispano cannons to outer bays shifted feed motor blisters outward on gun bay doors.
or
- Four 20 mm Hispano cannons with 120 rounds per gun, though this configuration was seldom implemented.
The repositioning of 20 mm Hispano cannons outward was coupled with adding a more potent .50-inch Browning M2/AN heavy machine gun with 250 rounds per gun in the inner bays, replacing outer Browning .303 guns. The first trial of this armament setup (modification 1029) took place on BS118, a Mark XI aircraft, in November 1943. This weapons arrangement subsequently became standard for all Spitfire Mk XIVs serving within the RAF 2nd Tactical Air Force as fighter aircraft. The enhanced firepower proved more effective in both aerial combat and ground attack roles.
The Mk XII operated with rounded wingtips replaced by shorter squared-off fairings; equipped with a single-stage supercharger Griffon II or IV engine used in Mk XIIs, it was optimized for low-altitude performance and did not carry the LF prefix typical of Merlin-powered Spitfires. Beginning in early 1945, most Spitfire Mk XIVs also adopted clipped wingtips primarily to minimize skin wrinkling on wings; similarly, these aircraft did not receive an LF designation.
Revised Late Wing Design
With the Spitfire's engine power increasing and its maximum speeds rising, the likelihood of aileron reversal became a more significant concern. To address this, Supermarine's engineering team undertook a comprehensive wing redesign. The initial wing configuration had a theoretical threshold for aileron reversal at 580 mph (930 km/h), which was relatively low compared to several fighter aircraft of the same era. The updated wing, introduced on the Spitfire F Mk 21 and subsequent models, featured a 47 percent enhancement in structural rigidity. Additionally, the ailerons were redesigned using piano hinges combined with geared trim tabs, resulting in an increased theoretical aileron-reversal speed of 825 mph (1,328 km/h). This improved wing design debuted with the Spitfire XXI. The standard weapon loadout was updated to four 20mm Hispano II cannons or alternatively, the lighter and shorter Hispano V cannons, each supplied with 150 rounds.
Variants
The Mark numbers assigned in the aircraft designation system do not necessarily reflect a sequential timeline; for instance, the Mk IX was developed as an interim solution and entered production before the Mks VII and VIII. Modifications between marks were common—for example, some early Mk Vbs originated as converted Mk Ibs, while initial Mk IXs were adapted from Mk Vcs.
Until late 1942, the RAF consistently used Roman numerals for mark designations. From 1943 until 1948, newly introduced aircraft adopted Arabic numerals for their marks, although older types retained Roman numerals. After 1948, Arabic numerals became standard exclusively. Consequently, the Spitfire PR Mk XIX was redesignated as PR 19 post-1948. This article follows the convention of employing Roman numerals for Marks I through XX and Arabic numerals for Marks 21 through 24. The "Type" numbers (e.g., "Type 361") correspond to Supermarine's internal design reference numbers.
Mk IV / XX (Type 337)
On 4 December 1939, Supermarine's design department circulated a proposal exploring the adaptation of the Spitfire to incorporate the Rolls-Royce Griffon engine. Predicted performance included a top speed of 423 mph (681 km/h) at an altitude of 18,500 ft (5,639 m). However, ongoing development challenges with the Griffon engine delayed actual implementation until 1942, when flight testing of the Mk IV proved successful.
The Mk IV was powered by the Griffon IIB engine—a single-stage supercharged unit delivering 1,735 hp (1,293 kW). To accommodate the heavier Griffon powerplant, reinforced main longerons were installed along with larger radiator and oil cooler assemblies, although it retained the asymmetric under-wing radiator layout characteristic of single-stage Merlin engines. The Griffon's thrust line was positioned lower than that of the Merlin and incorporated a fixed downthrust angle of two degrees. Due to its larger size and altered placement, the engine cowling underwent significant reshaping: more pronounced blisters covered cylinder heads; an additional tear-drop shaped blister appeared on the upper front cowling to clear the magneto; and a deeper curve extended toward a longer spinner than previous versions. The lower cowling lost its distinctive "pigeon-chested" profile in favor of a gentler curve leading up to the spinner. Propulsion was provided by a four-bladed Rotol propeller measuring 10 ft 5 in (3.1 m). Apart from these modifications, the Mk IV airframe closely resembled that of the Merlin-powered Mk III. A notable difference for pilots was that the Griffon's propeller rotated counterclockwise from their perspective—opposite to the Merlin’s clockwise rotation—causing a strong slipstream effect that pushed the aircraft rightward on takeoff and necessitated left rudder input.
The prototype Mk IV DP845 conducted its maiden flight on 27 November 1941. It combined a full-span C wing with a smaller tail unit and retractable tailwheel. External bracket hinges beneath the wings indicated installation points for braking flaps; however, these flaps were soon removed. A mock-up six-cannon armament system—three guns per wing—was also trialed on this airframe. To prevent confusion with a renamed photographic reconnaissance variant, this aircraft was redesignated Mk XX before ultimately becoming known as the Mk XII.
Jeffrey Quill, Supermarine’s chief test pilot, was first to fly prototype DP845 (Mk IV/Mk XII), commenting:
Mk XII (type 366)
The Mk XII marked the introduction of the Griffon engine in operational Spitfires. Production of 100 units by Supermarine commenced in October 1942, with only two RAF squadrons equipped with this model. Early Mk XIIs were constructed from Mk Vc and Mk VIII airframes: initial versions retained fixed tailwheels, used Dunlop AH2061 "five spoke" mainwheels, and had small elevator balances. They housed a single 85-gallon main fuel tank, limiting their range to just over 380 miles (610 km) on internal fuel alone. All featured the larger rudder with pointed tips. The final 45 or so units were based on the Mk VIII platform, incorporating two wing fuel tanks each holding up to 14 gallons, larger horn balances, retractable tailwheels, undercarriage legs equipped with torque-links, "dished" leg fairings, and reinforced Dunlop AH10019 four-spoke wheels. Occasionally, these wheels were fitted with disc-style covers. A later version of the Identification Friend or Foe (IFF) system replaced the original tailplane tip aerials with a rod aerial mounted beneath the starboard wing. A notable advancement in Griffon-powered Spitfires was the adoption of a fully flush-riveted exterior finish, which was gradually implemented across all models.
Powered by a single-stage Griffon engine (variants II or IV), the Mk XII excelled in low to medium altitude performance but experienced diminished capabilities at higher elevations. To optimize handling at lower levels, all production aircraft featured clipped wings. Comparative trials against the Mk IX revealed the Mk XII was approximately 14 mph (23 km/h) faster at sea level but slower above 20,000 ft (6,100 m). Pilots generally regarded its handling as superior to earlier Spitfire versions, with clipped wings enhancing maneuverability through improved aileron responsiveness.
At lower altitudes, it ranked among the fastest aircraft globally; during a July 1942 speed trial at Farnborough, DP485 (now designated as the Mk XII), flown by Jeffrey Quill, outpaced both a Hawker Typhoon and a captured Focke-Wulf Fw 190, defying initial expectations.
Despite its speed advantage, pilots often struggled to capitalize on it during combat since German aviators avoided dogfights with any Spitfire variant below 20,000 feet (6,100 m) altitude. When engaged effectively, however, the Mk XII proved a formidable adversary, downing multiple Fw 190s and Messerschmitt Bf 109G fighters.[1] Toward the end of its frontline deployment in summer 1944, its velocity advantage at lower altitudes contributed significantly to its pilots being credited with destroying 82.5 V-1 Flying Bombs. The Mk XII model was phased out of service by September 1944.
Mk XIV (type 379)
Early Griffon-powered Spitfires exhibited subpar performance at high altitudes due to their single-stage supercharged engines. By 1943, Rolls-Royce engineers had developed the Griffon 61 series engine featuring a two-stage supercharger. Ultimately, a slightly altered version, the Griffon 65 series, was installed in the Mk XIV. This modification resulted in a significant enhancement in performance compared to the Mk IX. While initially constructed on the Mk VIII airframe, later production incorporated common upgrades such as a shortened fuselage, tear-drop canopies, and the E-Type wing with enhanced armament.
The Mk XIV differed from its predecessor, the Mk XII, by employing a longer Griffon 65 engine with a two-stage supercharger that generated 2,050 hp (1,528 kW) and was positioned 10 inches (25.4 cm) further forward. The upper section of the engine bulkhead was angled forward, creating a distinctive profile change along the rear edge of the upper cowling. A new five-bladed Rotol propeller measuring 10 ft 5 in (3.18 m) in diameter was standard, though one prototype, JF321, tested a six-bladed contra-rotating propeller system. The earlier "fishtail" ejector exhausts were replaced by circular-section exhaust stubs. Due to increased cooling demands of the Griffon engine, all radiators were enlarged and underwing housings were made deeper compared to previous models.
New flush-mounted "Amal" type cowling fasteners were introduced in greater numbers. The oil tank, previously located beneath the lower cowling in Merlin-powered variants, was relocated forward of the fuselage fuel tanks and its capacity increased from 6 to 10 gallons.
To counterbalance the heavier engine, radio equipment was shifted rearward within the fuselage and the access hatch moved from the left to the right side of the fuselage. Improved VHF radios allowed removal of the aerial mast in favor of a "whip" aerial positioned further aft on the fuselage spine. The extended nose length and stronger slipstream from the large five-bladed propeller necessitated a redesigned tail assembly featuring a taller and wider fin with an enlarged rudder area.[2][3]
The initial Griffon 60 series powered aircraft were six modified Mk VIII airframes designated Mk VIIIG (serials JF316 through JF321). Jeffrey Quill piloted the first of these on January 20, 1943:
One prototype, JF321, underwent trials with a Rotol six-bladed contra-rotating propeller assembly intended to counteract take-off torque effects common with large propellers. However, this system proved unreliable due to pitch control issues:
A similar contra-rotating propeller configuration was later adopted for production Seafire models 46 and 47.
Upon entering service with 610 Squadron in December 1943, the Mk XIV represented a significant advancement in Spitfire development. Jeffrey Quill flew the first production aircraft RB140 in October 1943:
Performance figures included reaching 20,000 ft (6,100 m) altitude in just over five minutes and achieving maximum speed of 446 mph (718 km/h) at 25,400 ft (7,700 m).[4][5]
Many pilots initially found flying the Mk XIV challenging compared to earlier Spitfire variants. Don Healy of 17 Squadron, based at Madura, described it as:
...a demanding aircraft requiring acclimatization; personally I favored flying older Mk Vs... Even utilizing full control surfaces during takeoff, this powerful fighter tended to veer sideways.[6]
Despite handling difficulties, pilots valued its superior capabilities. Wing Commander Peter Brothers, officer commanding Culmhead Wing during 1944–45 and veteran of the Battle of Britain, remarked:
The aircraft impressed greatly with its near-vertical climb rate—it often surprised Luftwaffe pilots who expected an easy kill from above only to find themselves confronted head-on by an aggressively climbing Mk XIV at full throttle![7]
Fuel capacity for F Mk XIVs totaled 109.5 gallons: two main tanks holding 84 gallons plus two leading-edge wing tanks containing 12.5 imperial gallons each; additional drop tanks ranging from 30 to 90 gallons could be attached. Internal fuel alone provided just over 460 miles (740 km) range due to higher consumption by the Griffon engine compared to earlier Merlin-powered models. By late 1944 an auxiliary rear fuselage tank holding an extra 33 gallons was installed on some Spitfire XIVs extending internal range to approximately 850 miles (1,370 km) when combined with a 90-gallon drop tank.[8] Versions equipped with "tear-drop" canopies carried about 64 gallons internally; consequently F and FR Mk XIV variants achieved ranges exceeding 610 miles (980 km), or up to 960 miles (1,540 km) when fitted with a full external drop tank.[8]
The aircraft’s initial operational role included intercepting V1 flying bombs where it outperformed all other Spitfire variants in success rate. Introduction of high-octane (150 octane) fuel mid-1944 allowed increasing engine boost pressure by +25 lbs (80.7"), raising top speed by roughly 30 mph (26 kn; 48 km/h) to about 400 mph (350 kn; 640 km/h) at 2,000 ft (610 m).[9]
By December 1944 six squadrons equipped with Mk XIV fighters formed part of the 2nd Tactical Air Force serving as their principal high-altitude air superiority asset across northern Europe.[10]
A service issue encountered involved localized wrinkling of wing and fuselage skin near load-bearing attachment points; although Supermarine assured no critical structural weakening occurred nor imminent failure risk existed, RAF directives mandated clipping wings on all F and FR Mk XIVs starting early in 1945.[11]
Spitfire XIVs reached South-East Asian Theatre units by June 1945 but arrived too late for combat against Japanese forces.[1][12] Post-war rumors suggested several Mk XIVs were buried at an airfield in Burma following hostilities.
FR Mk XIV
Towards the end of 1944, several high-back, full-span Mk XIV aircraft were modified by the Forward Repair Unit (FRU) to include a single camera mounted either on the port or starboard side; this alteration matched the conversion applied to FRU-modified FR Mk IXc models. To facilitate this, a new hatch resembling the radio hatch on the port side was added on the starboard side, with both hatches equipped with camera ports enclosed in streamlined blisters. Apart from these changes, this variant of the FR Mk XIVe remained largely consistent with the standard version. These field conversions were assigned to 430 Squadron RCAF. Subsequently, factory-built versions, also designated as FR Mk XIVe, featured a later cut-down rear fuselage with a teardrop-shaped canopy, camera ports on either or both sides without blisters, and an extra rear fuel tank holding 34 gallons, which extended the aircraft’s operational range to approximately 610 miles (980 km) using internal fuel alone. Primarily deployed for low-altitude missions, these production FR Mk XIVe models were equipped with clipped wingtips.
A total of 957 Mk XIVs were manufactured, with over 430 being FR Mk XIV variants. After World War II, many surplus Mk XIVs were sold to various international air forces; among these, 132 units were delivered to the Royal Belgian Air Force, 70 to the Royal Indian Air Force, and 30 reconnaissance versions were supplied to the Royal Thai Air Force.
Mk XV and Mk XVII
The designations XV and XVII (15 and 17) were specifically reserved for naval adaptations known as the Seafire, aligning the Spitfire numbering system with that of its naval counterpart.
Mk XVIII (Mk 18) (type 394)
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The Mk 18 represented an evolution of the Mk XIV model. It shared many features including the Griffon 65 engine and cockpit improvements but incorporated additional fuel capacity and a redesigned, more robust wing structure. Its flight characteristics closely mirrored those of its predecessor, which meant it was not subjected to separate performance evaluations. Both fighter and fighter reconnaissance versions were produced.
Although developed during wartime, the Mk 18 did not enter service before the conflict ended. Production continued until early 1946; however, it was only in January 1947 that 60 Squadron stationed at RAF Seletar, Singapore, received this variant. Subsequently, other squadrons operating in the Far East and Middle East also adopted it. Approximately 300 units of both F Mk 18 and FR Mk 18 types were built before manufacturing ceased in early 1946. Operational deployment was limited mainly to engagements against insurgents during the Malayan Emergency. Additionally, in 1947, the Royal Indian Air Force acquired 20 former RAF Mk 18 aircraft.
Mk XIX (Mk 19) (types 389 and 390)
The Mk XIX represented the final and most effective photographic reconnaissance adaptation of the Spitfire. It merged elements from the Mk XI with the Griffon engine utilized in the Mk XIV. The initial batch of 25 units, designated as type 389, was produced before subsequent models incorporated the pressurized cockpit from the Mk X and expanded fuel storage to 256 gallons—approximately three and a half times the capacity of the original Spitfire. These later aircraft were classified as type 390.
Entering operational service in May 1944, the Mk XIX swiftly supplanted the earlier Mk XI variant by war’s end. Production totaled 225 aircraft, concluding in early 1946; nevertheless, these planes remained active in frontline RAF units until April 1954.
In 1951, at the request of US Naval Intelligence, RAF reconnaissance flights using Spitfire PR Mk 19s operated over Hainan Island (People's Republic of China), launching from Kai Tak Airport in Hong Kong. The last known combat-related mission involving a Mk 19 occurred in 1963 during battle trials against an English Electric Lightning. The purpose was to develop tactics for RAF Lightnings potentially engaging piston-engine fighters such as North American P-51 Mustangs amid the contemporary Indonesian conflict.
Mk XX (type 366)
The designation Mark XX was assigned to the original Griffon-powered prototype DP845 to prevent confusion with the renamed Spitfire PR Mk IV series.
A second Mark XX, DP851, initially equipped with a Griffon II engine, took flight in August 1942. It was subsequently re-engined with a Griffon 61 in December and reclassified as the Mk 21 initial prototype.
Mk 21 (type 356)
By early 1942, it became clear that Spitfires powered by the new two-stage supercharged Griffon 61 engine required a more robust airframe and wing structure. This necessity led to the development of the Mk 21, which initially suffered from unsatisfactory flight characteristics that tarnished the Spitfire’s esteemed reputation. The wings were redesigned with reinforced internal structures and thicker alloy skinning, resulting in a torsional stiffness increase of 47 percent. This enhancement permitted a theoretical aileron reversal speed elevation to approximately 825 mph (1,328 km/h). The ailerons were enlarged by five percent and replaced the Frise-balanced design with continuous piano hinges; extended by eight inches and featuring straighter trailing edges, this altered wing shape diverged from previous elliptical designs. The armament for the Mk 21 was standardized to four Hispano II 20mm cannons with 150 rounds each, eliminating machine guns.
The Griffon engine powered an 11 ft (3.4 m) diameter five-bladed propeller, approximately 7 in (18 cm) larger than that used on the Mk XIV. To accommodate this larger propeller, undercarriage legs were extended by 4.5 in (11 cm) and widened by 7.75 in (19.7 cm) to improve ground handling stability. A lever mechanism shortened the undercarriage legs by about 8 in (20 cm) during retraction due to spatial constraints; conversely, it extended them upon landing. The main wheels featured larger four-spoke designs reinforced for increased load capacity; postwar modifications replaced these with wider three-spoke wheels suitable for operations on concrete or asphalt surfaces. When retracted, triangular doors fully enclosed the wheels within their wells.
The initial production Mk 21s retained the Mk XIV airframe configuration. The first genuine Mk 21 prototype, PP139, flew in July 1943; production commenced with LA187 on March 15, 1944. However, modifications introduced sensitivity to trim adjustments. During late-1944 and early-1945 trials, LA201 exhibited poor control characteristics leading to critical assessments by the Air Fighting Development Unit (AFDU):
Supermarine expressed significant concern since Castle Bromwich had been repurposed for Mk 21 production with increasing output daily. Test pilot Jeffrey Quill remarked:
Following extensive flight testing and subtle control refinements—including changes to trim tab gearing—the major issues were resolved by March 1945 trials. An AFDU report on LA215 noted marked improvements:
Operational deployment began in January 1945 with No. 91 Squadron RAF. Although combat opportunities against the Luftwaffe were limited before war’s end, on April 26, 1945, two Mk 21s reportedly attacked and sank a German midget submarine caught surfaced. Postwar cancellations reduced total production to only 120 units completed; forty delivered to Shoeburyness in 1946 were employed for "lethality" tests involving removal and destruction of leading edges—some aircraft had logged fewer than five flight hours.
Mk 22 (type 356)
The Mk 22 closely resembled the Mk 21 but featured a shortened rear fuselage topped by a teardrop canopy and upgraded electrical systems operating at 24 volts instead of prior models’ twelve volts. Most units incorporated enlarged tail surfaces akin to those on the Supermarine Spiteful design. Production totaled 287 aircraft—260 constructed at Castle Bromwich and an additional twenty-seven at Supermarine’s South Marston facility.
Only one regular RAF squadron, No. 73 Squadron stationed on Malta, operated the Mk 22 extensively; however, twelve Royal Auxiliary Air Force squadrons also employed this variant until March 1951. Additionally, it served at flying refresher schools. By May 1955, remaining F.22s were retired from RAF service; many were returned to Vickers-Armstrongs for refurbishment before being sold internationally to Southern Rhodesian, Egyptian, and Syrian air forces.
Mk 23 (type 372)
The intended Mk 23 model was based on modifying a Mk 22 airframe with an altered wing featuring an increased incidence angle that raised the leading edge by approximately 2 inches (51 mm)—aimed at improving forward visibility during flight along with enhancing high-speed and dive performance. This hand-built wing first appeared on a modified Mk VIII ('JG204') tested from July 1944 but yielded unsatisfactory results.
Subsequently, Supermarine decided to develop a new prototype derived from the Mk 21 prototype PP139, designated F Mk 23 and intended for renaming as the Supermarine Valiant. However, because handling remained imperfect with this wing design, plans for building an operational Mk 23 based on the Mk 22 airframe were abandoned.
Mk 24 (type 356)
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The final iteration of the Spitfire series—the Mk 24—shared similarities with its predecessor but incorporated increased fuel storage via two rear fuselage tanks each holding approximately thirty-three gallons (150 liters). It also featured zero-point fittings beneath wings for rocket projectile armaments.
All units possessed enlarged tail assemblies identical to those on the Supermarine Spiteful model; additional refinements included adjustments to trim tab gearing that enhanced handling characteristics further. The F Mk 24 achieved a top speed near 454 mph (731 km/h) and could ascend to an altitude of 30,000 ft (9,100 m) within eight minutes—comparable with other advanced piston-engine fighters of its time.
Designed primarily as an interceptor fighter, this variant demonstrated multi-role flexibility including fighter-bomber operations carrying one 500 lb (230 kg) bomb plus two 250 lb (110 kg) bombs alongside standard rocket rails under wings.
Armament consisted of four Hispano cannon firing twenty-millimeter shells; late-production aircraft employed lighter short-barrelled electrically-fired Hispano Mark V guns due to operational experience indicating greater destructive power was necessary against increasingly armored enemy aircraft.
A total of eighty-one Mk 24s were produced—twenty-seven converted from existing Mk 22 airframes—with final delivery occurring in February 1948. They remained in use until circa 1952 within No. 80 Squadron RAF; some then transferred to Hong Kong Auxiliary Air Force service until about 1955.
Introduced into service near war’s end in late 1945, this model differed substantially from early Spitfires such as the original K5054 prototype: it weighed nearly twice as much yet delivered almost double power output along with an eighty percent climb rate improvement—largely attributable to adoption of Rolls-Royce Griffon engines replacing earlier Merlin powerplants.
Powered by a Rolls-Royce Griffon 61 V12 liquid-cooled engine rated at 2,050 hp (1,530 kW), featuring two-stage supercharging provided exceptional high-altitude performance previously lacking in earlier variants.
Production
Following severe damage inflicted upon primary manufacturing facilities at Itchen and Woolston by Luftwaffe attacks in September 1940, Supermarine shifted all Spitfire construction into multiple "British shadow factories". By war’s conclusion there existed ten principal factories alongside numerous smaller workshops responsible for component fabrication.
Castle Bromwich remained a key production site supported by these shadow factories.
Production figures below are sourced from Air International (1985) supplemented by serial number data compiled by Morgan and Shacklady (2000). Initial production dates correspond with first known serial-numbered aircraft deliveries; note that early XIV models originated from conversions of existing VIII airframes while protracted development delayed operational deployment of later variants such as Mk 21 until January 1945.
| Mark | Manufacturer(s) | Quantity Produced | Notes |
|---|---|---|---|
| F Mk XII | Supermarine | 100 | First unit delivered: October 13, 1942 |
| F Mk XIV / FR Mk XIV | Supermarine | 957 | First unit RB142 flown October 28, 1943 |
| F Mk XVIII | Supermarine | 300 | First unit June 1945 |
| PR Mk XIX | Supermarine | 224 | First unit RM626 May 1944 |
| F Mk 21 | Castle Bromwich | 120 | First unit LA187 January 27, 1944 |
| F Mk 22 | Supermarine & Castle Bromwich | 287 (27 +260) | First unit March 1945 |
| F Mk 24 | Supermarine | 54 | First unit March 1946 |
Videography
External links
- The Spitfire Site Archived 17 August 2020 at the Wayback Machine
- Alan Le Marinel's Supermarine Spitfire Resource
- Performance Evaluations of the Spitfire
- Warbird Alley – Details on Operational Spitfires
- K5054 – History of the Supermarine Type 300 Prototype and Production Models
- National Heritage Warbird Foundation
Template:Supermarine Spitfire Template:Supermarine aircraft
- ↑ 1.0 1.1 Thomas 2008
- ↑ Cooke October 1978, pp.489, 491–492.
- ↑ Price 2002, pp. 204–216.
- ↑ Price 1999, p. 217.
- ↑ Data based on JF319, one of six initial Mk XIV conversions from Mk VIII frames tested at Boscombe Down; production versions featured varied supercharger gearing.
- ↑ McKinstry 2007, p. 355.
- ↑ McKinstry 2007, p. 357.
- ↑ 8.0 8.1 Cite error: Invalid
<ref>tag; no text was provided for refs namedMorgan and Shacklady 2000, p.420. - ↑ Price 2002, p. 205.
- ↑ Shores and Thomas 2005, p. 297.
- ↑ Morgan and Shacklady 2000, pp. 411–412.
- ↑ Price 1999, pp. 205–206.
- ↑ Air International (1985), p.187; Morgan & Shacklady (2000)
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