Showing posts with label Hawker. Show all posts
Showing posts with label Hawker. Show all posts

Sunday, March 13, 2011

Hawker Typhoon

Hawker Typhoon
Typhoon Ib EK139 N "Dirty Dora" of 175 Sqn. being armed with 500 lb (227 kg) concrete practice bombs in late 1943.
Role Fighter-bomber
National origin United Kingdom
Manufacturer Hawker Aircraft
Designed by Sydney Camm
First flight 24 February 1940
Introduced 1941
Retired 1945
Primary users Royal Air Force
Royal Canadian Air Force
Number built 3,317[1][2]
Variants Hawker Tornado
Hawker Tempest
Hawker Sea Fury
The Hawker Typhoon was a British single-seat fighter-bomber, produced by Hawker Aircraft. While the Typhoon was designed to be a medium-high altitude interceptor, and a direct replacement for the Hawker Hurricane, several design problems were encountered, and the Typhoon never completely satisfied this requirement.[3] Other external events in 1940 prolonged the gestation of the Typhoon.
Nicknamed the Tiffy in RAF slang, the Typhoon's service introduction was also plagued with problems, and for several months the aircraft faced a doubtful future.[3] In 1941 the Luftwaffe brought the formidable Focke-Wulf Fw 190 into service. As the only fighter in the RAF inventory capable of catching the Fw 190 at low altitudes, the Typhoon secured a new role as a low-altitude interceptor.[4] In addition, the Typhoon won the support of pilots such as Roland Beamont. Through their dedication the Typhoon established itself in roles such as night-time intruder[5] and a long-range fighter. From late 1942 the Typhoon was equipped with bombs; from late 1943 ground attack rockets were added to the Typhoon's armoury. Using these two weapons, the Typhoon became one of the Second World War's most successful ground-attack aircraft.[6]

Contents

  • 1 Design and development
    • 1.1 Early Typhoon modifications
    • 1.2 Early tail failures
    • 1.3 Long-range fighter and fighter-bomber
    • 1.4 Further modifications
    • 1.5 Typhoon carrier fighter
  • 2 Operational service
    • 2.1 An effective weapon
    • 2.2 Captured Typhoons
  • 3 Flying the Typhoon
  • 4 Operators
  • 5 Survivors
    • 5.1 Typhoon Memorial Site
  • 6 Specifications (Typhoon Mk Ib)

Design and development

Even before the new Hurricane was rolling off the production lines in March 1937, Sydney Camm had moved on to designing its replacement. This was to be a large fighter designed around the large and more powerful 24 cylinder Napier Sabre engine. The work proved useful when Hawker received Specification F.18/37 from the Air Ministry in January 1938 which asked for a fighter based on either the Sabre or the Rolls-Royce Vulture engine.[7] Both engines used 24 cylinders and were designed to be able to deliver over 2,000 hp (1,491 kW); the difference between the two was primarily in the arrangement of the cylinders – an H-block in the Sabre and an X-block in the Vulture.[8]
RAF Typhoon at RAF Hendon Museum clearly showing the large "chin" radiator beneath the nose
The two designs became known as the "R" and "N" (from the initial of the engine manufacturer) and were very similar; the Vulture-powered R type (the Tornado) had a rounder nose profile and a ventral radiator, whereas the Sabre-powered N (the Typhoon) had a flatter deck and a chin-mounted radiator. The basic design of both was a combination of traditional Hawker and more modern construction techniques; the front fuselage structure, from the engine mountings to the rear of the cockpit, was made up of bolted and welded duralumin or steel tubes[nb 1] while the rear fuselage was a flush riveted, semi-monocoque structure.[8] The forward fuselage and cockpit skinning was made up of large, removable duralumin panels, allowing easy external access to the engine and engine accessories and most of the important hydraulic and electrical equipment.[9][10]
The design used a large 41-foot-7-inch (12.67 m) shallow-angle inverted gull wing of NACA 22 wing section, with a thickness to chord ratio of 19.5% at the root tapering to 12% at the tip;[11] this was much thicker than those on designs like the Supermarine Spitfire. This wing had great structural strength, provided plenty of room for fuel tanks and a heavy armament, and helped the aircraft to be a steady weapons platform.[12] Wing area was 279 sq ft (29.6 sq m).[13] The inner wings, outboard of the fuselage had a 1° anhedral while the outer wings, attached to the inner just outboard of the undercarriage legs, had a dihedral of 5½°.[8] Each of the inner wings incorporated two fuel tanks; the "main" tanks, housed in a bay outboard and to the rear of the main undercarriage bays, had a capacity of 40 gallons while the "nose" tanks, built into the wing leading edges, forward of the main spar,[9] had a capacity of 37 gallons each.[9][14] Also incorporated into the inner wings was an undercarriage with a track of 13 ft 6¾ in.[15] Although the Typhoon was expected to achieve 460 mph (740 km/h) in level flight, at just over 400 mph (644 km/h) the thick wings created a large drag rise and prevented higher speeds.[nb 2][16] Tests revealed that the Typhoon was capable of 410 mph at 20,000 feet (6,100 m), although the climb rate and performance above that level was considered disappointing.[17] If the Typhoon was dived at speeds of over 500 mph (805 km/h) the drag rise led to buffeting and trim changes. The problems with compressibility led to Camm designing thinner wings with a laminar flow section, leading to the Tempest as a follow on to the Typhoon.[18]
The first flight of the first Typhoon prototype, P5212, made by Hawker's Chief test Pilot Philip Lucas from Langley, was delayed until 24 February 1940 because of the problems with the development of the Sabre engine. On 9 May 1940 the prototype suffered from a mid-air structural failure, at the join between the forward fuselage and rear fuselage, just behind the pilot's seat. Philip Lucas could see daylight through the split but, instead of baling out, he was able to land the stricken Typhoon and was later awarded the George Medal.[19][20] On 15 May the Minister of Aircraft Production, Lord Beaverbrook, ordered that resources should be concentrated on the production of five main aircraft types (Spitfire, Hurricane, Whitley, Wellington and the Blenheim). As a result development of the Typhoon was slowed, production plans were postponed and test flying continued at a reduced rate.[21]
A second prototype, P5216 first flew on 3 May 1941. In the meantime the Air Ministry had given Hawker an instruction to proceed with the construction of 1,000 of the new fighters. It was felt that the Vulture engine was more promising, so the order covered 500 Tornadoes, 250 Typhoons, with the balance to be decided once the two had been compared. It was also decided that because Hawker was dealing with increasing Hurricane production the Tornado would be built by Avro while Gloster would build the Typhoons at Hucclecote.[20] As a result of good progress by Gloster the first production Typhoon R7576 was first flown on 27 May 1941 by Michael Daunt, just over three weeks after the second prototype.[3]

Early Typhoon modifications

As was usual with front line Second World War RAF aircraft, the Typhoon was modified and updated regularly, so that a 1945 production example looked quite different from one built in 1942. In the last months of the war a number of older aircraft were taken out of storage and overhauled, sometimes seeing active service for the first time; for example, R7771 was from one of the first production batches, built in 1942 with the car-door canopy and other early production features. This Typhoon was delivered to, and served on the Fighter Interception Unit in 1942.[22] In February 1945 R7771 was listed as being in front line service on 182 Sqn.; by then it was fitted with a clear-view "bubble" hood, rocket rails and other late series features.[nb 3]
Unidentified early Typhoon with 45 gallon drop tanks and unfaired cannon; note the retractable step (above starboard wheel).
The Typhoon was first produced with forward-opening side doors (complete with wind-down windows), with a transparent "roof" hinged to open to the left. The first 162 Typhoons featured a built-up metal-skinned fairing behind the pilot's armoured headrest; the mast for the radio aerial protruded through the fairing.[23] From mid- to late 1941 the solid metal aft canopy fairing was replaced with a transparent structure (later nicknamed "The Coffin Hood"),[24] the pilot's head armour plate was modified to a triangular shape and the side cut-outs were fitted with armoured glass; the first production Typhoon to be fitted with this new structure was R7803. All earlier aircraft were quickly withdrawn and modified.
The first problem encountered with the Typhoon after its entry into service was the seepage of carbon monoxide fumes into the cockpit. In an attempt to alleviate this, longer exhaust stubs were fitted in November 1941 ("Mod [modification] 239"), and at about the same time the port (left) cockpit doors were sealed. The Pilot's Notes for the Typhoon recommended that "Unless Mod. No. 239 has been embodied it is most important that oxygen be used at all times as a precaution against carbon-monoxide poisoning."[25] In fact, the problem was never entirely solved, and the standard procedure throughout the war was for Typhoon pilots to use oxygen from engine start-up to engine shut down.[26] In addition to carbon monoxide seepage, pilots were experiencing unpleasantly high cockpit temperatures; eventually a ventilation tube helped alleviate, but did not solve the problem. In addition two small, rear opening vents were added below the port side radio hatch, just below the canopy, although these were later removed.[nb 4][28]
P5212 carried an armament of 12 .303 in (7.7 mm) Brownings, set in groups of six in each outer wing panel. This was the armament fitted to the first 110 Typhoons, known as the Typhoon IA.[nb 5] P5216 carried an armament of four belt-fed 20 mm (.79 in) Hispano Mk II cannon, each with 140 rounds per gun; this version was the Typhoon IB.[3] Later in 1943, after experiments by Roland Beamont of 609 Squadron, removable fairings were fitted to the cannon barrels as standard.

Early tail failures

One of the worst problems afflicting Typhoons was the loss of the entire tail sections of some early aircraft; this occurred mainly during high-speed dives. It was eventually determined to be caused by a combination of factors, including harmonic vibration, which could lead to early metal fatigue, and a weak transport join just forward of the horizontal tail unit. Several modifications were made to alleviate these fuselage failures; Initially a steel strap was fitted internally across the rear fuselage transport joint in September 1942. This was a temporary measure, superseded by Mod 286 (modification number 286). For Mod 286 20 alloy "fishplates" were riveted externally across the rear fuselage transport joint; internally some of the rear fuselage frames were strengthened. This was a permanent measure designed to stop in-flight rear fuselage structural failures. From December 1942 through to March 1943 all Typhoons without this modification were taken out of service and modified. This was introduced on the production line from the 820th production aircraft EJ902.[29]
A Charles E. Brown photo of EK286, "Fiji V, Morris Headstrom Fiji" a brand new presentation aircraft, at Gloster's Hucclecote airfield, April 1943. The photo gives a clear view of the "car-door" cockpit entry; the rear view mirror under a perspex blister can be seen on the hinged canopy roof.
Another modification made to the tail unit was the replacement of the external mass balance weights on the rudder by an internal mass balance weight on a slightly redesigned rudder; this was fitted from mid-1942. Suspicion then fell on the internal elevator mass balance weights, and modified versions of these were fitted from May 1943 on. This was also designed to alleviate rear fuselage failure due to harmonic vibration failure of the bracket holding the weight assembly. Finally this entire unit was completely replaced with a redesigned assembly from August 1944.[30]
Although these modifications reduced the numbers of Typhoons being lost due to tail assembly failure, there were still some tail failures right up to the end of the Typhoon's operational life, which cost at least 25 aircraft and the lives of 23 pilots.[30][nb 6]

Long-range fighter and fighter-bomber

From early 1943 the wings were plumbed and adapted to carry cylindrical 45-gallon drop tanks[nb 7], increasing the Typhoon's range from 690 miles (911 km) to up to 1,090 miles (1,754 km). This enabled Typhoons to range deep into France, the Netherlands and Belgium. Some units, such as 609 Squadron and 198 Squadron, were able to achieve notable success in both air combat and ground attack operations using these long-range Typhoons.[31]
As production continued, the Typhoon's role changed from a low-level interceptor fighter to a fighter bomber; bomb racks capable of carrying 500-lb (227 kg) bombs were being fitted to the wings from October 1942. These were first used operationally by 181 Squadron. By mid-1943, all Typhoons off the production line were capable of carrying bombs. Bigger, solid rubber, grooved "anti-shimmy" tail wheel tyres were introduced in March 1943 on all Typhoons from the 1,001st production aircraft, EK238. The new tyres helped to make heavier, bomb-laden Typhoons more manageable during ground manoeuvres. With the introduction of the bomb racks, small extensions were added to the cannon shell case ejector slots. These allowed the casings to clear bombs or drop tanks suspended from the wing racks.[32]
Also associated with the fitting of bombs was the introduction of reinforced main wheels. On these, the openings were smaller than those on the earlier wheels, and the "spokes" were flatter and thicker. Bigger brake discs were also fitted; at first this only applied to "Bombphoons"; eventually all Typhoons used these brakes. After tests conducted in 1943, it was determined that the Typhoon was capable of carrying a 1,000-lb (454 kg) bomb under each wing. With the increased load, it was decided that the extra takeoff performance conferred by a four-bladed propeller was an advantage; this led to the adoption of a four-blade propeller unit (de Havilland or Rotol) from early 1944. In turn, the larger tail planes of the Hawker Tempest were fitted from June 1944 on; these improved the handling characteristics of the Typhoon when carrying 1,000-lb (454 kg) bombs.[33] Originally they were only used on "Bombphoons". Starting in the MN production series, all Typhoons had the larger tail unit.[34][nb 8]
In June 1943, Hawker fitted a Typhoon with steel "Mark I" rocket rails, four under each wing; trials at the A & AEE and AFDU showed that the combination of the RP-3 rocket and the stable, high-speed platform of the Typhoon was promising. Carrying the eight rails and rockets, it was found that the top speed was reduced by 38 mph (61 km/h), with no adverse handling effects. As a result, the Mk I rails and RP-3s were first fitted to production aircraft of 181 Sqn. in October 1943, and by D-Day, 2 TAF were able to field eleven RP Typhoon squadrons and seven "Bombphoon" squadrons. Later in 1944, attempts were made to increase the firepower by "double banking" rockets on each rail, enabling the Typhoon to carry 16 rockets. The problems involved in operating Typhoons from 2 TAF airstrips meant that this option was never fully utilised, although some Typhoons did fly operationally with 12 rockets, using double-banked rockets on the inner rails.[36] When extra range was required, Typhoons could also operate carrying a drop tank and two rockets outboard of the tank under each wing. From December 1944, aluminium "Mark III" rails, which weighed 240 lb (109 kg) per set, replaced the steel Mk Is (480 lb [218 kg] per set).[37][nb 9]
Throughout its service life, the Typhoon airframe was prone to a high-frequency vibration while in flight, such that pilots reported that touching the cockpit walls was akin to receiving a mild electric shock. Although not dangerous, it was uncomfortable, and a specially sprung seat was designed and fitted. This vibration was alleviated to some extent with the introduction of the four-bladed propeller.[38]

Further modifications

Late model Typhoon of 440(RCAF) Squadron. Note the bomb rack under the wing. Rows of five gallon jerrycans dominate the foreground
From early 1942 a rear-view mirror was mounted in perspex blister moulded into the later "car-door" canopy roofs. This modification was not very successful, because the mirror was subject to vibration.[39] From late 1942 all new-build Typhoons replaced the aerial mast with a whip aerial mounted on the rear fuselage.
The gun camera was moved from the leading edge of the outer port wing to the starboard engine bearers, sighting through an opening in the lower engine cowling. The new location was prone to engine vibration but, because the film was still usable, the camera stayed in this location. Removable exhaust fairings were fitted in mid-1943. These were soon discarded when they were found to be of little benefit to aircraft performance, plus they complicated maintenance.[32]
The "car-door" canopy structure was replaced by a clear, one piece sliding "bubble" canopy after test flights were conducted in early 1943. These new canopies provided a far superior field of view to the car-door type, and from November 1943 all production aircraft, starting with JR333, were so fitted.[34][39] Many older Typhoons were retrofitted with the new canopies; it is believed that the first modified Typhoon was R8843 DJ-S, flown by New Zealander Wing Commander Desmond J. Scott, C/O of the Tangmere Wing from September 1943.[40][nb 10] With the new canopy the pilot's head armour was reshaped and the identification light behind the aerial mast structure on "car-door" canopy aircraft was removed.[39]
In 1943, one Typhoon, R7881 was converted to a prototype night fighter (N.F. Mk. IB), fitted with A.I. (Airborne Interception, i.e., radar) equipment, a special night-flying cockpit and other modifications. Also in 1943, five Typhoons, R8889, R8891, R8925, DN323 and EJ906 were modified to "Tropical" standard by fitting of an air filter in a fairing behind the main radiator housing. R8891, DN323 and EJ906 underwent trials in Egypt with 451(RAAF) Squadron during 1943.[41]
In late 1943 Mk III IFF replaced the Mk I and the tailplane tip to fuselage IFF aerials were replaced by a "bayonet" aerial under the wing's centre section. A Rebecca transponder unit was fitted in 1944, with the associated aerial appearing under the centre section.
Once Typhoons started operating from forward landing grounds in Normandy, it was found that the dust clouds stirred up by propeller wash consisted of over 80% of hard, abrasive material which was damaging the Sabre engines; the sleeve valves in particular were subject to excessive wear, and it was calculated that engines would last for three take-offs. As a result a "dome deflector" was designed and manufactured at great speed by Napier, and most Typhoons were fitted with this within a week. In operational service these mushroom-shaped filters, which became red hot, had a propensity for being blown off the air intake at high speed whenever a Sabre engine backfired. They were soon replaced by drum-shaped filters designed by the RAE and Vokes; these had "cuckoo clock" doors in front which swung open with the pressure changes caused by engine backfires. This standardised filter became Typhoon Mod.420.[42]
The Typhoon FR IB was developed in early 1944 and was used as a tactical reconnaissance fighter. In this version the port inner cannon was removed and three F.24 (one forward facing 14-inch (360 mm) and two vertical five inch) cameras were carried in its place.[nb 11] Few FR IBs were built, and most served with 268 Squadron, starting in July 1944. The aircraft was never popular with the pilots, who preferred the older Mustang Is and IAs, and the inherent engine and airframe vibrations meant that photos were invariably blurred. As a consequence of these problems the FR IB was phased out in January 1945.
At the end of June 1944 a decision was taken to fit as standard tropical air filters, similar to those fitted on the three Typhoons which had been sent to North Africa in 1943. One thousand sets of the filters were to be manufactured and fitted to frontline Typhoons as Mod. 421; it was estimated that these could be fitted to all Typhoons on the production lines by the end of September. Research shows that late Typhoons starting in the RB--- series were fitted with the filters, as were some rebuilt aircraft from earlier production batches. Mod 421 appeared as a streamlined rectangular "hump" just behind the main radiator fairing and between the inner wheel doors.[42]
A small, elongated oval static port appeared on the rear starboard fuselage in late 1944. This was apparently used to more accurately measure the aircraft altitude.
Late production Typhoon of a Canadian squadron. Clear view canopy, grooved "anti-shimmy" tailwheel, four blade propeller, "bayonet" IFF aerial, no landing lights.
One Typhoon, R8694, was used by Napier for trials with more powerful Sabre IV cooled using an annular radiator and driving a four bladed propeller; the new engine and radiator arrangement required substantial modifications to the forward fuselage and engine bearer structures. Although a maximum speed of 452 mph (727 km/h) was claimed by Napier, it was decided that the modifications would not be worthwhile, mainly because of the promising development of the Tempest and the disruption to Typhoon production.[43][44]

Typhoon carrier fighter

In 1941 Hawker tendered the Hawker P.1009 "Fleet Fighter" in response to specification N.11/40 for a carrier-based fighter. A new centre section was to be fitted, extending the wingspan to over 45 ft (13.7 m): the wings themselves were to swing and fold parallel to the fuselage, with the leading edges pointing upwards. The rear fuselage was to be longer and a vee arrestor hook and associated catapult gear was to be fitted. The design chosen was to eventuate as the Blackburn Firebrand.[45]

Operational service

The Spitfire Vs which equipped the bulk of Fighter Command squadrons were outclassed in combat with the Focke-Wulf Fw 190 and were suffering heavy losses. The Typhoon was rushed into squadron service (with Nos. 56 and 609 Squadrons) in an attempt to counter the Fw 190. This decision proved to be a disaster, and several Typhoons were lost to unknown causes. Because of these problems the Air Ministry began to consider halting production of the Typhoon. The in-flight tail failure was eventually identified, albeit only because one pilot survived and was able to explain what had happened; Mod 286 was a partial remedy, although there were still failures right up to the end of the Typhoon's service life.
US-A was flown by Squadron Leader T.H.V Pheloung (Oamaru, New Zealand) April 1943.[41][nb 12] An 18-inch-wide (460 mm) yellow recognition stripe is visible on the upper wing.
The Sabre engine was also a constant source of problems, notably in colder weather, where it was very difficult to start.
The Typhoon did not begin to mature as a reliable aircraft until the end of 1942, when its good qualities—seen from the start by S/L Roland Beamont of 609 Squadron—became apparent. It was extremely fast, tough and capable, and its unplanned bomb load was doubled and then doubled again.[46] During late 1942 and early 1943, the Typhoon Squadrons on the South Coast were finally effective in countering the Luftwaffe's "tip and run" low-level nuisance raids, shooting down a score or more fighter-bomber Fw 190s. The first two Messerschmitt Me 210 fighter-bombers to be destroyed over the British Isles fell to the guns of Typhoons in late 1942, and during a daylight raid by the Luftwaffe on London on 20 January 1943, five Fw 190s were destroyed by Typhoons.
As soon as the aircraft entered service it was immediately apparent the profile of the Typhoon resembled a Fw 190 from some angles, and this similarity caused more than one "friendly fire" incident with Allied anti-aircraft units and other fighters. This led to Typhoons being marked up with high visibility black and white stripes under the wings, a precursor of the markings applied to all Allied aircraft on D-Day.

An effective weapon

By 1943 the RAF needed a dedicated ground attack fighter more than a "pure" fighter, and the Typhoon was suited to the role. The powerful engine allowed the aircraft to carry a massive load of (eventually) up to two 1,000 lb (454 kg) bombs, equal to the light bombers of only a few years earlier. The bomb-equipped aircraft were nicknamed "Bombphoons" and entered service with No. 181 Squadron, formed in September 1942.
Rare wartime colour photograph of an unidentified Typhoon
From September 1943 Typhoons could also be armed with four "60 lb" RP-3 rockets under each wing[nb 13]. In October 1943, No. 181 Squadron made the first Typhoon rocket strikes. Although the rocket projectiles were inaccurate and took some considerable skill to aim properly and allow for the drop after firing, "the sheer firepower of just one Typhoon was equivalent to a destroyer's broadside."[47] Against the Wehrmacht's tanks, the rockets needed to hit the thin-walled engine compartment or the tracks to have any chance of destroying or disabling the tank. Analysis of destroyed tanks after the Normandy battle showed a "hit-rate" for the air-fired rockets of only 4%.[48] Inaccuracy notwithstanding, the rockets (backed by the Typhoon's four 20 mm cannon) proved highly effective against many targets, such as unarmoured "soft-skinned" vehicles, road transport, trains and small sea craft. By the end of 1943, 18 rocket-equipped Typhoon squadrons formed the basis of the RAF's Second Tactical Air Force ground attack arm in Europe. In theory the rocket rails and bomb-racks were interchangeable; in practice, to simplify ordnance supply-lines, some 2 TAF Typhoon squadrons (such as 198 Squadron) used the rockets only, while other squadrons were armed exclusively with bombs.
By D-Day, in June 1944, the RAF had 26 operational squadrons of Typhoon IBs. The aircraft proved itself to be the most effective RAF tactical strike aircraft, both on interdiction raids against communications and transport targets deep in North Western Europe prior to the invasion, and in direct support of the Allied ground forces after D-Day.
198 Sqn. Typhoons on airfield B.7 Rucqueville-Martragny, France, in July 1944. MN526 TP-V has the larger Tempest tailplane and a four bladed propeller. A heavy dust cloud has been stirred up by the taxiing aircraft.
A system of close liaison with the ground troops was set up by the RAF and army: RAF radio operators in vehicles equipped with VHF R/T travelled with the troops, often close to the front line. In situations where air support was needed they were able to call up Typhoons operating in a "Cab Rank", which then continuously attacked the targets marked for them (usually with smoke shells fired by mortar or artillery) until they were destroyed.
A German counter-attack, starting on 7 August, at Mortain, in the Falaise pocket, threatened Patton's break-out from the beachhead. This was repulsed by 2nd TAF Typhoons, which destroyed or damaged some 81 vehicles. In the Vire area, where the British Army was under attack, Typhoons flew 294 sorties on one day, firing 2,088 rockets and dropping 80 tons (73 tonnes) of bombs. Dwight D. Eisenhower, the Supreme Allied Commander, said of the Typhoons; "The chief credit in smashing the enemy's spearhead, however, must go to the rocket-firing Typhoon aircraft of the Second Tactical Air Force. The result of the strafing was that the enemy attack was effectively brought to a halt, and a threat was turned into a great victory."[49] On 24 October 1944, 146 Typhoon Wing attacked a building in Dordrecht where senior members of the German 15th Army staff were meeting; 17 staff officers and 55 other officers were killed.
Armourers loading RP-3 rockets with 60 lb High Explosive heads onto steel Mk. I rails. The large hinged gun-bay doors are open. The weathered Invasion stripes are on upper and lower wing surfaces, indicating this photo was taken some time in June 1944.
On 3 May 1945, the Cap Arcona, the Thielbek and the Deutschland were sunk in four separate attacks by RAF Hawker Typhoon 1Bs of No. 83 Group RAF, 2nd Tactical Air Force: the first by 184 Squadron, second by 198 Squadron led by Wing Commander John Robert Baldwin, the third by 263 Squadron led by Squadron Leader Martin T.S. Rumbold and the fourth by 197 Squadron led by Squadron Leader K.J. Harding.[50]
The top scoring Typhoon ace was Group Captain John Robert Baldwin (609 Squadron and Commanding Officer 198 Squadron, 146 (Typhoon) Wing and 123(Typhoon) Wing), who claimed 15 aircraft shot down during 1942–44. Some 246 Axis aircraft were claimed by Typhoon pilots during the war.[51]
Production of the Typhoon, almost entirely by Gloster, was 3,317 machines.
Hawker developed an improved version of the Typhoon, the Typhoon II but the differences between it and the Mk I were so great that it was effectively a different aircraft and was renamed the Tempest.
Once the war in Europe was over, the RAF was quick to remove the aircraft from front line squadrons; by October 1945 the Typhoon was no longer in use as an operational aircraft,[52][53] with many of the wartime Typhoon units (for example, 198 Squadron) either being disbanded or renumbered.

Captured Typhoons

By 1943, with its change of role to ground attack, the Typhoon was constantly operating over enemy territory: inevitably some flyable examples were to fall into German hands.
The first Typhoon to be flown by the Luftwaffe was EJ956 SA-I of 486(NZ) Sqn. On 23 March 1943, two aircraft flown by F/O Smith and F/S Mawson were on a "Rhubarb" over France.[nb 14] Just as they were crossing the coast at low altitude, Mawson's Typhoon was hit by light flak. He managed to belly-land in a field near Cany-Barville, but the aircraft was captured before he could destroy it. The Typhoon was repaired and test flown at Rechlin (a German equivalent to RAE Farnborough) and later served as T9+GK with "Zirkus Rosarius". EJ956 overturned and was written off during a forced landing near Meckelfield, 10 August 1944.[28][41]
On 14 February 1944, another Typhoon was captured and later flown in Zirkus Rosarius. JP548 of 174 Squadron, force landed after engine failure near Marigny, France; the pilot, F/O Proddow evaded capture. This Typhoon crashed at Reinsehlen on 29 July 1944, killing Feldwebel Gold.[41]
A third unidentified Typhoon (possibly an aircraft of 1 Squadron) was also thought to have been flown by the Luftwaffe.

Flying the Typhoon

Flight Lieutenant Ken Trott flew Typhoons with 197 Squadron and recalled:
Rather a large aircraft shall we say, for a single-engine fighter. Terrific power. Quite something to control. I liked it from the point of view of speed and being a very stable gun platform. You could come in on a target at 400 mph and the thing was as steady as a rock.[54]
In early March 1943 at Tangmere the then new Squadron Leader of 486(NZ) Squadron, Des Scott, flew a Typhoon for the first time:
She roared, screamed, groaned and whined, but apart from being rather heavy on the controls at high speeds she came through her tests with flying colours...Applying a few degrees of flap we swung on down into the airfield approach, levelled out above the runway and softly eased down on to her two wheels, leaving her tail up until she dropped it of her own accord. We were soon back in her bay by the dispersal hut, where I turned off the petrol supply cock. After a few moments she ran herself out and with a spit, sob and weary sigh, her great three-bladed propeller came to a stop. So that was it: I was drenched in perspiration and tired out...[55]
The performance limitations for speed were noted on the pilot's notes, published by the Air Ministry. Indicated airspeed for diving was set at 525 mph (845 km/h). The Typhoon could, if needed, be flown at 300 mph (480 km/h) with the Cockpit "hood" open. Flight with undercarriage and flaps down could be made without incident, at the respective speeds of 210 and 155 mph (340 and 249 km/h). When the aircraft was carrying bombs, the speed could not exceed 400 mph (for stability issues).[56]
Notes for the management of the fuel system stated that indicated airspeeds (IAS) in excess of 380 mph (610 km/h) were not advisable when fitted with auxiliary drop tanks. Tanks were jettisoned at about 200 mph (320 km/h), but in an emergency, a release at 350 mph (560 km/h) was permitted. Tanks were to be ejected in straight and level flight only.[57] General flying ability was positive. The maximum climbing rate was 185 mph (298 km/h) up to 16,000 ft (4,900 m) reducing speed by 3 mph (4.8 km/h) per 1,000 ft (300 m) above this mark. In stability terms, the aircraft was stable "directionally" and "laterally" but slightly unstable longitudinally, except at high speed, when it was just stable. Aileron control was light and effective up to maximum speed, but at very low speed response was sluggish, particularly when carrying ordnance. The elevator control was rather light and could not be used harshly. There was a tendency to "tighten up" in a looping plane. If "black out" conditions were accidentally induced in steep turns or aerobatics the control column was to be pushed forward "firmly".[58]
Stalling speeds were quite low. The typical Typhoon trait, as with most aircraft, was to drop a wing sharply with flaps either up or down. The stalling speeds varied. The various loads depended on external fittings. All-up weight plus 2 x 500 lb (230 kg) bombs (12,155 lb in total) with flaps up could induce a stall at 90–100 mph. With flaps down, stall was initiated at 70–75 mph. Normal all-up weight (11,120 lb) would see stall at 80–90 and 65–70 mph respectively. With all ammunition and nearly all fuel expended (9,600 lb) stall occurred at 75–80 and 65–70 mph.[59]

Operators

  • Australia Australia
  • Canada Canada
  • New Zealand New Zealand
  • United Kingdom UK

Survivors

Hawker Typhoon (replica) at Memorial de la Paix, Caen
Only one complete Hawker Typhoon still survives – serial number MN235 – and it is on display at the RAF Museum in Hendon, North London. It was previously on display at the National Air and Space Museum (NASM) (Smithsonian Institution) before being presented to the museum in commemoration of the RAF's 50th Anniversary in exchange for a Hawker Hurricane. The Hawker Typhoon replica at the Memorial de la Paix, Caen (France) had been reconstructed from some original components.
Hawker Typhoon RAF Hendon

Typhoon Memorial Site

On 9 June 1994, in recognition of the aircraft and crew's role in the liberation of Normandy, a Typhoon Memorial at Noyers Bocage was dedicated by Major M. Roland Heudier. Also present at the ceremony were General Yves Paul Ezanno DFC and bar and Squadron Leader Denis Sweeting, both former Squadron Leaders of 198 Squadron.[60]

Specifications (Typhoon Mk Ib)

Data from Mason 1991 unless otherwise stated[61]
General characteristics
  • Crew: One
  • Length: 31 ft 11.5 in[nb 15] (9.73 m)
  • Wingspan: 41 ft 7 in (12.67 m)
  • Height: 15 ft 4 in [nb 16] (4.66 m)
  • Wing area: 279 ft² (29.6 m²)
  • Empty weight: 8,840 lb (4,010 kg)
  • Loaded weight: 11,400 lb (5,170 kg)
  • Max takeoff weight: 13,250 lb [nb 17] (6,010 kg)
  • Powerplant: 3 or 4-blade de Havilland or Rotol propeller× Napier Sabre IIA, IIB or IIC liquid-cooled H-24 piston engine, 2,180, 2,200 or 2,260 hp (1,626, 1,640 or 1,685 kW) each
Performance
Armament
  • Guns: 4 × 20 mm Hispano Mk II cannon
  • Rockets: 8 × RP-3 unguided air-to-ground rockets.
  • Bombs: 2 × 500 lb (227 kg) or 2 × 1,000 lb (454 kg) bombs

Hawker Tornado

Tornado
Role Single seat fighter
Manufacturer Hawker Aircraft
First flight 6 October 1939
Primary user Royal Air Force
Number built 4 (3 prototypes and 1 production)
The Hawker Tornado was a British single-seat fighter aircraft design of World War II for the Royal Air Force as a replacement for the Hawker Hurricane. The planned production of Tornados was cancelled after the engine it was designed to use—the Rolls-Royce Vulture—proved unreliable in service. A parallel airframe with the Napier Sabre continued into production as the Hawker Typhoon.

Contents

  • 1 Design and development
    • 1.1 Technical description
    • 1.2 Flight trials
    • 1.3 Production
    • 1.4 Vulture engine
  • 2 Operators
  • 3 Specifications

Design and development

Shortly after the Hawker Hurricane entered service, Hawker began work on its eventual successor. Two alternative projects were undertaken: the Type N (for Napier), with a Napier Sabre engine, and the Type R (for Rolls-Royce), equipped with a Rolls-Royce Vulture power-plant. Hawker presented an early draft of their ideas to the Air Ministry who advised them that a specification was in the offing for such a fighter. The specification was released by the Minisitry as Specification F.18/37 after further prompting from Hawker.[1] the specification called for a single-seat fighter armed with 12 0.303 in (7.7 mm) machine-guns. A maximum speed of 400 mph (644 km/h) at 15,000 ft (4,572 m) and a service ceiling of 35,000 ft (10,668 m) were required. Two prototypes of both the Type N and R were ordered on 3 March 1938.

Technical description

Both prototypes were very similar to the Hurricane in general appearance, and shared some of its construction techniques. The front fuselage used the same swaged and bolted duralumin tube structure, which had been developed by Sydney Camm and Fred Sigrist in 1925. The new design featured an automobile-like side opening doors for entry, and used a large 40 ft (12 m) wing that was much thicker in cross section than those on aircraft like the Spitfire. The rear fuselage, from behind the cockpit, differed from that of the Hurricane in that it was a duralumin, semi-monocoque, flush-riveted structure. The all-metal wings incorporated the legs and wheel-bays of the wide-set undercarriage. The two models were also very similar to each other; the R plane had a rounder nose profile and a ventral radiator, whereas the N had a flatter deck and a chin mounted radiator. The fuselage of the Tornado ahead of the wings was 12 in (30 cm) longer than that of the Typhoon, the wings were fitted 3 in (76 mm) lower on the fuselage, and the radiator was located beneath the fuselage. The X-24 cylinder configuration of the Vulture required two sets of ejector exhaust stacks on each side of the cowling.[2]

Flight trials

On 6 October 1939, the first prototype (P5219) was flown by P.G. Lucas, having first been moved from Kingston to Langley for completion. Further flight trials revealed airflow problems around the radiator, which was subsequently relocated to a chin position. Later changes included increased rudder area, and the upgrading of the powerplant to the Vulture V engine. Hawker production lines focused on the Hurricane, and the completion of the second prototype (P5224) was thus significantly delayed. It featured the chin radiator, additional window panels in the fairing behind the cockpit, and the 12 .303 in (7.7 mm) machine guns were replaced by four 20 mm (.79 in) Hispano cannon. It was first flown on 5 December 1940, and was powered by a Vulture II, although as in the case of the first prototype, a Vulture V was later installed.

Production

In order to avoid upsetting the Hurricane lines, production was sub-contracted to Avro in Manchester[2] and Cunliffe-Owen Aircraft in Eastleigh, with orders for 1,760 and 200 respectively being placed in 1939. However only one of these aircraft, from Avro, was ever built and flown, this being R7936. Shortly after its first flight at Woodford, on 29 August 1941, the Vulture programme was abandoned, followed closely by the cancellation of the Tornado order. At that time four aircraft were at various stages of production at the Avro plant at Yeadon, West Yorkshire.

Vulture engine

The Vulture was effectively cancelled by Rolls-Royce in July 1941 due to the problems experienced in its use on the Avro Manchester, where it displayed a continual habit of erupting into flame in flight. The Merlin was also starting to deliver the same power levels. However, the Vulture engine installation in the Tornado was relatively trouble free[2] and the aircraft itself had fewer problems in flight than its Sabre-engined counterpart. The third prototype (HG641), the only other Tornado to fly, was flown on 23 October 1941, powered by a Bristol Centaurus CE.4S sleeve valve radial engine. This Tornado was built from two incomplete production airframes (R7937 & R7938) and was a test-bed for a number of Centaurus engine/propeller combinations and was the progenitor of the Hawker Tempest II.

Operators

 United Kingdom

Specifications

Orthographic projection of the second prototype Tornado, with the distinctive "beard" radiator, modified tail and fitted for four cannons. Inset profile of the first prototype in the original configuration looking very much like an enlarged Hurricane.
Data from Thomas & Shores [2], Mason[3][4]
General characteristics
  • Crew: One, pilot
  • Length: 32 ft 10 in (10.01 m)
  • Wingspan: 41 ft 11 in (12.78 m)
  • Height: 14 ft 8 in (4.47 m)
  • Wing area: 283 ft² (26.3 m²)
  • Empty weight: 8,377 lb (3,800 kg)
  • Loaded weight: 9,520 lb (4,318 kg) for P5219
  • Useful load: 2,291 lb (1,039 kg)
  • Max takeoff weight: 10,668 lb (4,839 kg)
  • Powerplant:Rolls-Royce Vulture II or V or Bristol Centaurus CE 4S X piston engine, Vulture II: 1,760 hp (1,312 kW)Vulture V: 1,980 hp (1,476), Centaurus: 2,210 hp (1,648 kW)
  • Propellers: 3 or 4 bladed propeller
    • Propeller diameter: 13 feet 3 in (Vulture: 12 feet 9 in)
  • *Fuel capacity: 140 gallons (636 Litres)
Performance
  • Maximum speed: 398 mph (641 km/h) for Vulture V at 23,300 ft (7,102 m). Centarus gave 402 mph (647 km/h) at 18,000 ft (5,486 m)
  • Service ceiling: 34,900 ft (10,640 m)
  • Wing loading: max takeoff: 37.7 lb/ft² (184.81 kg/m²)
  • Power/mass: max takeoff 5.38 lb/hp (3.58 kg/Kw)
  • Time to height: 7.2 min to 20,000 ft
Armament
  • Guns: Provision for 12 × .303 in (7.7 mm) Browning machine guns (1st prototype P5219) or 4 × 20 mm Hispano cannon. (2nd and Centaurus prototypes P5224, HG641).
Avionics
TR 9 VHF R/T fitted (P5224)

Hawker Tempest

Tempest
Tempest V prototype HM595
Role Fighter/Bomber
Manufacturer Hawker Aircraft Limited
Designed by Sydney Camm
First flight 2 September 1942
Introduced January 1944
Status Retired
Primary user Royal Air Force
Number built 1,702
Developed from Hawker Typhoon
Variants Hawker Sea Fury
The Hawker Tempest was a British fighter aircraft primarily used by the Royal Air Force (RAF) in the Second World War. The Tempest was an improved derivative of the Hawker Typhoon, and one of the most powerful fighter aircraft used during the war.

Contents

  • 1 Design and development
    • 1.1 Tempest Mark V
    • 1.2 Tempest II
    • 1.3 Tempest VI
    • 1.4 Drawing board designs
  • 2 Service history
    • 2.1 Tempest V in combat
  • 3 Variants
  • 4 Operators
  • 5 Specifications (Tempest V)

Design and development

During development of the Typhoon the design team, under the leadership of Sydney Camm, were already planning design improvements, this process resulting in the Hawker P. 1012 (or Typhoon II).[1]
Although the Typhoon was basically a good design, Camm and his design team were disappointed with the wing which proved to be too thick in its cross section; this created problems with the airflow and inhibited the performance of the aircraft, especially at higher altitudes. The Typhoon's wing, using a NACA 4 digit series wing section, had a maximum thickness to chord ratio of 19.5% (root) to 12% (tip).[2] In March 1940, engineers were assigned to investigate the new low drag laminar flow wing developed by NACA in the United States, which had been used in the new North American P-51 Mustang. A laminar flow wing adopted for the Tempest series had a maximum thickness to chord ratio of 14.5% at the root, tapering to 10% at the tip.[2] The maximum thickness of the Tempest wing was set further back at 37.5% of the chord versus 30% for the Typhoon's wing.[2]
The wingspan was originally greater than that of the Typhoon at 43 ft (13.1 m), but the wingtips were later "clipped" and the wing became shorter; 41 ft (12.5 m) versus 41 ft 7 in (12.7 m). The wing planform was changed to an elliptical shape to accommodate the 800 rounds of ammunition for the four 20 mm (.79 in) Hispano cannons, which were moved back further into the wing. The new elliptical wing had greater area than the Typhoon's.[nb 1]
However, the new wing design sacrificed the leading edge fuel tanks of the Typhoon; to make up for this loss in capacity, Hawker engineers added a new 21 in (53 cm) fuel bay in front of the cockpit, with a 76 gal (345 l) fuel tank.[2] In addition, two inter-spar wing tanks, each of 28 gal (127 l), were fitted on either side of the centre-section and, starting with late model Tempest Vs, a 30 gal (136 l) tank was carried in the leading edge of the port wingroot, giving the Tempest a total internal fuel capacity of 162 gal (736 l).[3] In service Tempests also carried two specially designed, streamlined, drop-tanks of 45 gal (204 l) giving a maximum of 360 gal (1,636 l) and an operational radius of 500 mi (805 km)[4]
Another important feature of the new wing was Camm's proposal that radiators for the new Napier Sabre IV engine were to be fitted into the leading edge of the wing inboard of the undercarriage. This eliminated the distinctive "chin" radiator associated with the Typhoon and improved aerodynamics.[2]
A further improvement of the Tempest wing over that of the Typhoon was the exceptional, flush riveted surface finish, essential on a high performance laminar flow airfoil.[5] Fortunately for the pilots the new wing and airfoil, and the four-bladed propeller unit, eliminated the high frequency vibrations that had plagued the Typhoon.[6]
The redesigned main undercarriage legs were longer and had a wider track (16 ft/5 m) to improve stability at the high landing speed of 110 mph (180 km/h), and to allow tip clearance for a new de Havilland four-blade, 14 ft (4 m) diameter propeller. The main undercarriage units were designed to incorporate a system of trunnions which shortened the legs as they retracted.[7] The main wheels also needed new thin tyres in order to fit within the wing. Finally, the retractable tailwheel was fully enclosed by small doors.
The Tempest I HM599. When first flown it had the "car-door" canopy and small tail unit also used on the Tempest V prototype HM595.
Camm and the Hawker design team placed a high priority on making their aircraft easily accessible to both air and ground crews; to this end the forward fuselage and cockpit areas of the earlier Hurricane and the Tempest and Typhoon families were covered by large removable panels providing access to as many components as possible, including flight controls and engine accessories. Both upper wingroots incorporated panels of non-slip coating. For the pilot a retractable foot stirrup under the starboard root trailing edge was linked to a pair of handholds which were covered by spring loaded flaps. Through a system of linkages, when the canopy was open the stirrup was lowered and the flaps opened, providing easy access to the cockpit. As the canopy was closed the stirrup was raised into the fuselage and the flaps snapped shut.
The new design was finalised by October 1941 and the Air Ministry issued specification F.10/41 that had been written to fit the aircraft. A contract for two initial prototypes was issued the next month. The aircraft was originally named the "Typhoon Mark II" but was renamed "Tempest" in January 1942 when more prototypes with various experimental configurations were ordered.[2] The problems experienced with delivery of engines led the Air Ministry to ask for six prototypes with different engines so that if a delay hit one engine an alternative would be available. This gave the Mk I (aircraft HM599) with a Sabre IV, two Mk IIs (LA602 and LA607) with the Centaurus IV, MK III (LA610) with a Griffon IIB, Mk IV (LA614) with a Griffon 61 and the Mk V (HM595) with the Sabre II.[8]
The first Tempest prototype, the Mark V, was first flown by Philip Lucas from Langley on 2 September 1942. This aircraft retained the Typhoon's framed canopy, automobile-style door, the Sabre II engine, and "chin" radiator.[8] It was quickly fitted with a bubble canopy like the later Typhoons and a modified tailfin that almost doubled the vertical tail surface area. The horizontal tailplanes and elevators were also increased in span and chord (these were also fitted to late production Typhoons.)[8]
Tempest V prototype HM595. This photo illustrates the early configuration with "car door" cockpit structure and small tail units.
Test pilots found the Tempest a great improvement over the Typhoon in performance; in February 1943 the pilots from the A&AEE at Boscombe Down reported that they were impressed by "a manoeuverable and pleasant aircraft to fly with no major handling faults".[6] The Air Ministry had already ordered 400 Tempests in August but production of the new Sabre IV engine ran into protracted problems and delays. The second prototype, the "Tempest Mark I" with the Sabre IV did not fly until 24 February 1943.[6] This prototype also had at first the older Typhoon cockpit structure and vertical tailplane. Elimination of the "chin" radiator did much to improve performance and the Tempest Mark I was the fastest aircraft Hawker had built to that time, attaining a speed of 466 mph (750 km/h).[9]
Continual problems with the Sabre IV meant that only one Mark I (HM599) was built; consequently Hawker went into production with the Sabre II engined "Tempest V". The first rolled off the production line on 21 June 1943.[10] The first Tempest Vs delivered had the long-barrelled 20 mm (.79 in) Hispano Mk II cannon. Later production aircraft used the short-barrelled 20 mm (.79 in) Hispano Mk V cannon, eliminating the protruding barrels—though these had not been as prominent as on the Typhoon.
The ultimate offshoot of the Typhoon and Tempest family was the Fury/Sea Fury.

Tempest Mark V

The first production Tempest V JN729 Small blisters covering the spar to spar boom securing bolts can be seen on the wing root fairing as can the longer barrels of the Hispano II cannon fitted to the first 100 Tempests.
The Mk V was a much different Tempest to the Mk I with many improvements over preceding variants. The Mk Vs received the initially problem-plagued Napier Sabre II series engines developing in excess of 2,000 hp (1,491 kW) with their H-24 cylinder configuration. Compared with the Mk I prototype, the wing root oil coolers were moved to a location directly behind the main "chin" radiator. The first production Tempest V, JN729 was first flown by test pilot Bill Humble on 21 June 1943.[11] Several of the early production aircraft underwent extensive service trials at Boscombe Down including clearances to be fitted with external stores, including 500 lb (227 kg) and 1,000 lb (454 kg) bombs and 3 in (76.2 mm) RP-3 rockets.[12][13] Examination of captured Fw 190s brought about improvements in the windscreen/ side windows; by careful design and positioning of the frame structure blind spots were reduced to an absolute minimum.
During production of the first batch of 100 (JNxxx serialled) Tempest Vs changes were progressively introduced:[nb 2]
The rear fuselage fuselage/empennage joint originally featured the 20 external reinforcing "fishplates" first seen fitted to the Typhoon. Sometime during this production batch the rear fuselage was modified and became detachable.[14] The first Tempest Vs used long barrelled 20 mm (.79 in) Hispano Mk. IIs which projected ahead of the wing leading edges. These were later replaced by short barrelled Mk. Vs which were flush with the leading edges. "Five spoke" wheels, of a similar pattern to those of the Typhoon, were later replaced by a reinforced "four spoke" pattern.
Initially, Tempest Vs used a built-up rear spar pick-up/bulkhead assembly (just behind the cockpit) which was adapted from the Typhoon. Small blisters on the upper rear wing root fairing covered the securing bolts. This was later changed to a new forged, lightweight assembly which connected to new spar booms: the upper wing root blisters were replaced by small "teardrop" fairings under the wings.[14] The new spar structure also allowed the wings to carry up to 2,000 lb (907 kg) of external stores. Also developed specifically for the Tempest by Hawker was a streamlined 45 gal (205 l) "drop tank" and carrier fairing; the redesigned wing incorporated the plumbing for these tanks, one to each wing.[10] The ailerons were fitted with spring loaded tabs which lightened the aerodynamic loads, making them easier for the pilot to use and dramatically improving the roll rate above 250 mph (402 km/h).[10] Different models of the Sabre II were introduced. The later versions were capable of producing over 2,400 hp (1,789 kW) on emergency boost for short periods of time.[12]
As in all mass-produced aircraft, there may have been some overlap of these features as new components became available. In mid to late 1944 other features were introduced to both the Typhoon and Tempest: A Rebecca transponder unit was fitted, with the associated aerial appearing under the portside centre section. A small, elongated oval static port appeared on the rear starboard fuselage, just above the red centre spot. This was apparently used to more accurately measure the aircraft's altitude.
Unusually, in spite of the Tempest V being the RAF's best low to medium altitude fighter, it was not equipped with the new Mk IIC gyroscopic gunsight, an asset which was fitted in RAF Spitfires and Mustangs from mid-1944 and one which considerably improved the chances of shooting down opposing aircraft. Tempest pilots continued to use the Mk.IIL reflector gunsight until just after World War II, when the gyro-gunsight was introduced in Tempest IIs.
In December 1943, the US Army Air Forces Materiel Command tested the Tempest V JN729 and concluded with: The Tempest should prove to be a very excellent fighter airplane. It is easy to fly and exhibits very desirable fighter characteristics coupled with excellent performance.[12]
Externally the Tempest V bore a strong resemblance to the Typhoon: the longer nose, thinner wings and larger tail unit, with a gracefully curved dorsal fin, enhanced the looks of the fighter, and were the most noticeable differences.
SN345 with experimental 47 mm class P guns.
Two Tempest Vs, EJ518 and NV768, were fitted with Napier Sabre Vs and experimented with several different Napier made annular radiators, with which they resembled Tempest IIs. This configuration proved to generate less drag than the standard "chin" radiator, contributing to an improvement in the maximum speed of some 11 to 14 mph.[15] NV768 was later fitted with a ducted spinner, similar to that fitted to the Fw 190 V1.[9][16]
Another experimental Tempest V was SN345, which was fitted with two Vickers 47 mm "P" guns, one under each wing in a long "pod".[17][nb 3]

Tempest II

The prototype Tempest II LA602 showing original Typhoon tail unit.
The decision to drop the Hawker Tornado allowed Sydney Camm and his design team to transfer the alternative engine proposals for the Tornado to the more advanced Typhoon II (later to be renamed "Tempest"). As a result the Tempest was designed from the outset to use the Bristol Centaurus 18 cylinder radial engine as an alternative to the liquid cooled engines which were also proposed. Two Centaurus powered Tempest Mk II prototypes were to be built.[19]
The first Tempest Mark II, LA602, flew on 28 June 1943 powered by a Centaurus IV (2,520 hp/1,879 kW) driving a four-blade propeller. LA602 initially flew with a Typhoon-type fin and rudder unit. This was followed by the second, LA607, which first flew on 18 September 1943 and was assigned to engine development. Apart from the new engine and cowling, the Tempest II prototypes were similar to early series Tempest Vs. The main airframe difference was the addition of carburettor air intakes in the inner leading edges of both wings, with an oil cooler and air intake in the inner, starboard wing.
The radial engine installation owed much to examinations of a captured Focke-Wulf Fw 190, and was unprecedentedly clean and effective. One adopted feature was the use of individual exhaust stubs, laid out in a row down either side of the fuselage, rather than the front collector and large single exhaust used by the Centaurus powered Tornado. In spite of the promise of a more reliable powerplant than the Sabre, there were frustrating problems, including overheating, unreliable and leaking exhausts, insufficient crankshaft lubrication and propeller reduction gear seizures. There were also problems with vibration, but they were fixed by replacing the original "rigid" eight-point engine mounts with six-point rubber-packed shock mounts. In a further attempt to alleviate engine vibration, the four blade propeller was replaced with a five blade unit; eventually, a finely balanced four bladed unit was settled on.[20]
Physically, the Tempest II was longer than the Tempest V (34 ft 5 in/10.5 m versus 33 ft 8 in/10.3 m) and 3 in (76 mm) lower. The weight of the heavier Centaurus engine (2,695 lb/1,222 kg versus 2,360 lb/1,070 kg) was offset by the absence of a heavy radiator unit, so that the Tempest II was only some 20 lb (9 kg) heavier overall. Performance was improved; maximum speed was 442 mph (711 km/h) at 15,200 ft (4,633 m) and climb rate to the same altitude took four and a half minutes compared with five minutes for the Tempest V. The service ceiling was increased to 37,500 ft (11,430 m)[4]
Late production Tempest F.B Mk. II showing bomb racks under the wings
The Centaurus was generally regarded as superior to the Sabre, particularly in terms of reliability, and the engine and Tempest airframe proved an excellent match. The combination looked so promising that a contract for 500 of the type was placed as far back as September 1942, but Gloster was overloaded with production of the Typhoon and development of the Gloster Meteor, and the company could not handle the additional load.
In 1943, the Tempest Mark II production contract was allocated to Bristol, and the switch delayed production even more. The first Tempest II was rolled off the line on 4 October 1944. With the end of the Second World War in sight, orders for the Tempest II were trimmed or cancelled; after 50 Tempest IIs had been built at Bristol's Banwell facility, production was stopped and shifted back to Hawker.
A total of 452 Tempest IIs were built, including 136 basic Mark IIs and 316 "Fighter Bomber Mark IIs" (FB II). They were built mostly by Hawker and generally with Centaurus V engines, and of that number, 300 were completed after the war. The Tempest II, despite its slightly improved performance and better reliability, never saw combat.
Tempest IIs produced during the war were intended for combat against Japan, and would have formed part of a proposed British Commonwealth long range bomber force based on Okinawa, Tiger Force.[21] The Pacific War ended before they could be deployed.
The RAF passed 89 Tempest FB IIs to the Indian Air Force in 1947, while another 24 were passed on to the Pakistani Air Force.

Tempest VI

Various engineering refinements that had gone into the Tempest II were incorporated into the last Tempest variant, the "Tempest VI", which was fitted with a Napier Sabre V engine with 2,340 hp (1,700 kW). The more powerful Sabre V required a bigger radiator which displaced the oil cooler and carburettor air intake from the radiator's centre. Air for the carburettor was drawn through intakes on the leading edge of the inner wings, with the oil cooler being fitted behind the radiator. Most Tempest VIs were tropicalised with an air filter fitted in a fairing on the lower centre-section. Hundreds of Tempest VIs were ordered, though only 142 were built. The last piston-engined fighter in RAF service was a Tempest VI.
For a long time it was thought that there were Tempest VIs converted for target towing: none of the service histories of the aircraft show TT conversions and no supporting photographic evidence has been found.

Drawing board designs

In 1944, in response to F.13/44 Sydney Camm started a design, the P.1027, for a slightly enlarged Tempest powered by a Rolls Royce R.46, which was projected to develop around 2,500–4,000 hp (1,864–2,983 kW). This engine would have driven eight-blade contra-rotating propellers. The radiator was to be moved into a ventral bath under the rear fuselage and wing centre section: the wingspan was 41 ft (12.5 m) and the length was 37 ft 3 in (11.4 m). The design was soon dropped in favour of the P.1030, which featured wing leading edge radiators and larger overall dimensions of 42 ft (12.8 m) wingspan and 39 ft 9 in (12.1 m) long. Top speed was expected to be in the region of 508 mph (817 km/h), with a rate of climb of 6,400 ft/min (1,951 m/min). Service ceiling was projected to be 42,000 ft (12,802 m).[22]
Both tenders were dropped when Camm decided to follow the more promising jet engine designs he was working on.

Service history

Tempest V in combat

Early production Tempest V of 486 Sqn. April 1944. JN766 still has factory applied black and white Typhoon style underwing recognition bands (see "Invasion stripes").
The Tempest V was in the hands of operational squadrons by April 1944; 3 Squadron was the first to be fully equipped, closely followed by 486 (NZ) Squadron (the only Article XV unit to be equipped with the Tempest during the Second World War). A third unit—56 Squadron—initially kept its Typhoons and was then temporarily equipped with Spitfire IXs until sufficient supplies of Tempests were available.[23][nb 4] By the end of April 1944, these units were based at RAF Newchurch a new "Advanced Landing Ground" (ALG), where they formed 150 Wing, commanded by Wing Commander Roland Beamont. The new Wing was part of the Second Tactical Air Force (2nd TAF).
Most of the operations carried out by 150 Wing comprised high altitude fighter sweeps, offensive operations known as "Rangers" (long-range sorties inside enemy territory, specifically to attack ground vehicles) and anti-shipping reconnaissance. In June 1944, however, the first German V-1 flying bombs were launched against London and the Tempest's excellent low-altitude performance made it one of the preferred tools for dealing with the small fast-flying unmanned missiles. 150 Wing was transferred back to the ADGB, where the Tempest squadrons racked up a considerable percentage of the total RAF kills over the flying bombs (638 of a total of 1,846 destroyed by aircraft).
Early Tempest V of 3 Sqn. at Newchurch. Note Invasion stripes painted on by the ground crew; the longer cannon barrels can be seen on the port-side wing.
In September 1944 Tempest units, based at forward airfields in England, supported Operation Market Garden, the Airborne attempt to seize a bridgehead over the Rhine. On 21 September 1944, as the V1 threat had receded, the Tempest squadrons were redeployed to the 2nd TAF, effectively trading places with the Mustang III squadrons of 122 Wing, which became part of the ADGB units deployed on bomber escort duties.[24] 122 Wing now consisted of 3 Sqn., 56 Sqn., 80 Sqn., 274 Sqn. (to March 1945), and 486(NZ)Sqn. From 1 October 1944 122 Wing was based at B.80 Volkel Air Base near Uden, in the Netherlands.[24] In February 1945 33 and 222 Sqns. of 135 Wing converted from Spitfire Mk IXs and, in March, were joined by 274 Sqn. 135 Wing was based at B.77 Gilze-Rijen airfield in Holland.[25]
The Tempest's primary role was to carry out "armed reconnaissance" operations deep behind enemy the front lines. The Tempest was particularly well suited to the role because of its high speed at low to medium altitudes, its long range when equipped with two 45 gallon drop tanks, the good firepower of the four 20mm cannon and the good pilot visibility.[26] Armed reconnaissance missions were usually flown by two sections (eight aircraft), flying in Finger-four formations, which would cross the front-lines at altitudes of 7,000 to 8,000 feet: once the Tempests reached their allocated target area the lead section dropped to 4,000 feet or lower to search for targets to strafe, while the other section flew cover 1,000 feet higher and down-sun. After the first section had carried out several attacks it would swap places with the second section and the attacks would continue until ammunition had been exhausted, after which the Tempests would return to base at 8,000 feet.[27] Because the most profitable targets were usually some 250 miles from base the Tempests usually carried two 45 gallon drop tanks which were turned on soon after take-off. Although there were fears that the empty tanks would explode if hit by flak the threat never eventuated and, because they could be difficult to jettison, they were routinely carried throughout an operation with little effect on performance, reducing maximum speed by 5 to 10 mph and range by 2%.[27][28]
In December 1944 52 German fighters were downed and 89 trains destroyed, for the loss of 20 Tempests. Following the Luftwaffe's Operation Bodenplatte of 1 January 1945, 122 Wing bore the brunt of low to medium altitude fighter operations for the Second Tactical Air Force. Spitfire XIVs of 125 and 126 Wings often provided medium to high altitude cover for the Tempests. The Wing came under intense pressure, losing 47 pilots in January.
Tempests also scored a number of kills against the new German jets, including the Messerschmitt Me 262. Hubert Lange, a Me 262 pilot, said: "the Messerschmitt Me 262's most dangerous opponent was the British Hawker Tempest — extremely fast at low altitudes, highly-manoeuvrable and heavily-armed."[29] Some were destroyed with a tactic known to 135 Wing as the "Rat Scramble":[30][31] Tempests on immediate alert took off when an Me 262 was reported to be airborne. They did not intercept the jet, but instead flew towards the Me 262 and Ar 234 base at Rheine-Hopsten.[32][nb 5] The aim was to attack jets on their landing approach, when they were at their most vulnerable, travelling slowly, with flaps down and incapable of rapid acceleration. The Germans responded by creating a "flak lane" of over 150 quadruple 20 mm (.79 in) guns at Rheine-Hopsten, to protect the approaches.[33] [nb 6] After seven Tempests were lost to flak at Rheine-Hopsten in a single week, the "Rat Scramble" was discontinued. For a while, in March 1945 a strict "No, repeat, No ground attacks" policy was imposed; this only applied for a few days.[34]
In air-to-air combat the Tempest units achieved an estimated air combat success ratio of 7:1, accomplishing a 6:1 ratio against single seat enemy fighters.[nb 7] The top scoring Tempest pilot was Squadron Leader David C. "Foobs" Fairbanks DFC, an American who joined the Royal Canadian Air Force in 1941. By mid-1944, he was flying with 274 Squadron. When he was shot down and made a POW in February 1945, he had destroyed 11 or 12 German aircraft (and one shared) to make him the highest scoring Tempest ace.[35]

Variants

Hawker Tempest II, RAF Museum, Hendon.
  • Typhoon Mk II : The original designation of the Hawker Tempest.
  • Tempest Mk I : Prototype fitted with the Napier Sabre IV piston engine with oil coolers and radiators placed in the wing to reduce drag, one aircraft.
  • Tempest Mk III : Prototype fitted with the Rolls-Royce Griffon piston engine.
  • Tempest Mk IV : Tempest Mk III prototype re-engined with a Rolls-Royce Griffon 61 piston engine.
  • Tempest Mk V : Single-seat fighter, fighter-bomber aircraft, powered by the Napier Sabre II piston engine, 801 built at Langley.
    • Early series Tempest Mk V : The first 100 production aircraft were fitted with four long-barrel 20 mm (.79 in) Mark II Hispano cannons and continued to use some Typhoon components.
    • Mid to late series Tempest Mk V : The other 701 production aircraft were fitted with four short-barrel 20 mm Mark V Hispano cannons and other production line changes.
    • Tempest TT Mk 5 : After the Second World War a number of Tempest Mk Vs were converted into target tugs.
  • Tempest F Mk II : Single-seat fighter aircraft for the RAF, powered by a Bristol Centaurus radial piston engine, 402 built by Hawker at Langley and 50 by Bristol Aeroplane Company, Banwell.
    • Tempest FB Mk II : Single-seat fighter-bomber with underwing pylons for bombs and rockets.
  • Tempest F Mk VI : Single-seat fighter aircraft for the RAF engined with the Sabre V (2,340 hp), 142 built.

Operators

Specifications (Tempest V)

Data from Jane's Fighting Aircraft of World War II:[12][37]
General characteristics
  • Crew: One
  • Length: 33 ft 8 in (10.26 m)
  • Wingspan: 41 ft 0 in (12.49 m)
  • Height: 16 ft 1 in (4.90 m (tail down))
  • Wing area: 302 ft² (28 m²)
  • Empty weight: 9,250 lb (4,195 kg)
  • Loaded weight: 11,400 lb (5,176 kg)
  • Max takeoff weight: 13,640 lb (6,190 kg)
  • Powerplant:Napier Sabre IIA or IIB or IIC liquid-cooled H-24 sleeve-valve engine:, 2,180 hp (1,625 kW) Sabre IIA at + 9 lb/in² boost at 7,000 ft (2,133 m), 4,000 rpm [nb 8]
  • Propellers: Four-bladed Rotol or de Havilland propeller
Performance
  • Maximum speed: 432 mph (695 km/h) Sabre IIA at 18,400 ft (5,608 m), Sabre IIB 435 mph at 19,000 ft (700 km/h at 5,791 m)
  • Range: 740 mi (1,190 km)
    1,530 mi (2,462 km) with 90 gal (409 l) drop tanks
  • Service ceiling: 36,500 ft (11,125 m)
  • Rate of climb: 4,700 ft/min (23.9 m/s)
  • Wing loading: 37.75 lb/ft² (184.86 kg/m²)
  • Power/mass: 0.21 hp/lb (0.31 kW/kg)
Armament
  • 4 × 20 mm (.79 in) Mark II Hispano cannons, 200 rpg
  • 2 × 500 lb (227 kg) or 1,000 lb (454 kg) bombs
  • 8 × 3 in (76.2 mm) RP-3 rockets (post-Second World War)
  • Provision for 2 × 45 gal (205 l) or 2 × 90 gal (409 l) drop tanks.

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