Westland Whirlwind (fighter)

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This article describes the Second World War fighter aircraft. For the postwar helicopter of the same name, see Westland Whirlwind (helicopter).

Whirlwind
Westland Whirlwind in a rare Second World War colour photograph
Type	Heavy fighter
Manufacturer	Westland Aircraft Limited
Maiden flight	11 October 1938
Introduction	June 1940
Retired	October 1943
Primary user	Royal Air Force
Produced	1940 – January 1942
Number built	116

The British Whirlwind was a diminutive, twin-engine heavy fighter from the Westland Aircraft company. The Whirlwind was one of the fastest aircraft in the air when it flew in the late 1930s, and much more heavily armed than anything flying. Protracted development problems with its Rolls-Royce Peregrine engines delayed the entire project and only a relatively small number were built. During the Second World War only two RAF squadrons would be equipped with the Whirlwind, and despite successful use as a fighter-bomber, its service life was short.

Contents 1 Design and development 2 Operational history 2.1 An appraisal 3 Variants 4 Operators 5 Survivors 6 Specifications (Whirlwind) 7 See also 8 References 8.1 Notes 8.2 Bibliography 9 External links

[edit] Design and development

The Whirlwind's origin lay in the new aircraft being developed for the RAF after the last of the biplane fighters. With higher attack speeds giving shorter opportunities for firing on targets, it was decided to increase the minimum level of armament on their aircraft. Instead of two rifle calibre machine guns, eight were specified. At the same time it was recognised that guns such as the Hispano-Suiza with 20 mm exploding ammmunition offered another route to heavy firepower and requests were made for aircraft designs with four of these cannon.

A serious problem for air planners of the 1930s was that one could build a nimble combat aircraft only if it was small. Such an aircraft would have limited space for fuel, and would only have enough range to fight in defensive operations. A multi-engined fighter appeared to be the best solution to the problem of range, but it seemed that any fighter large enough to incorporate a substantial fuel load would be too unwieldy to fight its single-engine counterparts.

The Germans and U.S. pressed ahead with such programs anyway, resulting in the Messerschmitt Bf 110 and the Lockheed P-38. Soon the Luftwaffe was boasting that the 110 could beat any single-engine fighter, and do so, while operating at long ranges escorting their bombers. This piqued the interest of the Air Ministry who finally decided to try their hand at such a "destroyer" design and sent out a requirement to aircraft manufacturers. Gloster, Hawker and Westland all responded; the Gloster F.9/37 and Westland F.37/35 designs (from an earlier specification issued for a cannon-armed fighter) were given the go-ahead (Hawker was busy with the Hurricane).

Westland's design team, under the new leadership of Teddy Petter (who later designed the English Electric Canberra and Lightning), returned an aircraft that employed state-of-the-art technology. The fuselage was a small tube with a T-tail at the end, built completely of stressed-skin monocoque duraluminium. The pilot sat high under one of the world's first full bubble canopies, and the low and forward location of the wing made for superb visibility (except directly over the nose). In the nose were four 20 mm cannons, making it the most heavily armed fighter aircraft of its era with their clustering meaning there were no convergence problems as there are with wing-mounted guns.

The resulting design was quite small, only slightly larger than the Hurricane in overall size, but smaller in terms of frontal area. All of the wheels fully retracted and the entire aircraft was very "clean" with few openings or protuberances. Careful attention to streamlining and two 885 hp Peregrine engines powered it to over 360 mph (580 km/h), the same speed as the latest single-engine fighters, using much higher-powered engines. The speed quickly garnered it the nick-name Crikey, (a minced oath meaning "my god!" or more accurately "Christ's keys!").

The first prototype (L6844) flew on 11 October 1938 with production starting early the next year. It exhibited excellent handling and was very easy to fly at all speeds. The only exception was landing, which was all too fast. Fowler flaps were added to correct this problem, which also required the horizontal stabilizer (tailplane) to be moved up, out of the way of the disturbed air flow when the flaps were down. Hopes were so high for the design that it remained "top secret" for much of its development, although it had already been mentioned in the French press.

But there were problems as well. The aircraft actually had limited range, under 300 miles combat radius, which made it marginal as an escort. More troublesome were the continued failures of the Peregrine engines. Originally intended to be one of Rolls' main designs, the Merlin had become much more important to the war effort and the Peregrine was relegated to a secondary status. Soon the engine was cancelled outright and since much of the performance of the Whirlwind depended on the careful streamlining around that specific engine, there was little choice but to cancel the aircraft as well.

Westland argued for the creation of the Mk II model using two Merlin engines, but by this time the role was becoming less important. As Bomber Command turned to night bomber missions the need for an escort fighter became less important. By 1940, the Supermarine Spitfire was mounting 20 mm cannons, so the "cannon-armed" specification was also being met. The main qualities the RAF were looking for in a twin was range and ordnance load (to allow for the carriage of radar), which the Bristol Beaufighter could do just as well as the Whirlwind.

In 1941, the Luftwaffe started a number of extremely high-altitude bombing missions using specially modified Junkers Ju 86 bombers and Messerschmitt Bf 109 fighters carrying bombs. These were met by modified Spitfires with some success, but the pilots were extremely exhausted as a result of the forced-air breathing system. The Air Ministry then ordered a new purpose-built high-altitude fighter with a pressurized cockpit, and Westland responded with a new twin-engined design known as the Welkin. However, the Germans, unaware of the British problems, called off the attacks and the Welkin production was limited.

[edit] Operational history

In the end, only 114 Whirlwinds were produced in total, arming two squadrons (No. 263 Squadron RAF in July 1940 and No. 137 Squadron RAF in November 1941). Due to their good low-altitude performance, they were used primarily in interdiction roles and referred to as Whirlybombers. However, even this role was marginalized with the introduction of the Hawker Typhoon, and the Whirlwind was removed from service in late 1943.

The first Whirlwinds were delivered to No. 263 Squadron in July 1940, after the decision had been made that No. 263, not No. 25, would be the first RAF Whirlwind squadron. However, from then until October, production of the Peregrine engine was so slow that only 11 Whirlwinds could be delivered to the squadron. Due to slow deliveries and the transition from being an operational Hurricane squadron while transitioning to the new fighter, the squadron didn’t become operational with the Whirlwind until December 1940, but flew them until December 1943. A second Whirlwind squadron, No. 137, flew the type from September 1941 until June 1943.

One Whirlwind (P6972) was tested as a night-fighter in 1940 with No. 25 Squadron while the first prototype was tested with an armament configuration of 12 0.303 machine guns. Another Whirlwind had a single 37-mm cannon fitted.^[1][2]

[edit] An appraisal

Philip J.R. Moyes notes in Aircraft in Profile 94: The Westland Whirlwind, “The basic feature of the Whirlwind was its concentration of firepower: its four closely-grouped heavy cannon in the nose had a rate of fire of 600 lb./minute – which, until the introduction of the Beaufighter, placed it ahead of any fighter in the world. Hand in hand with this dense firepower went a first-rate speed and climb performance, excellent manoeuvrablity and a fighting view hitherto unsurpassed. The Whirlwind was, in its day, faster than the Spitfire down low and, with lighter lateral control, was considered to be one of the nicest ‘twins’ ever built… From the flying viewpoint, the Whirlwind was considered magnificent.”

Bruce Robertson, in The Westland Whirlwind Described^[3] quotes a 263 Squadron pilot as saying, "It was regarded with absolute confidence and affection.”

At low level, the aircraft was a devastating fighter-bomber, armed with both cannons and bombs, and it could hold its own with the Bf 109 at low-level. The performance of the Peregrine fell off at altitude, so the Whirlwind was used almost exclusively at low level.

The aircraft is well summed up by Francis K. Mason’s comments in Royal Air Force Fighters of World War Two, Vol. One:

“Bearing in mind the relatively small number of Whirlwinds that reached the RAF, the type remained in combat service, virtually unmodified, for a remarkably long time…The Whirlwind, once mastered, certainly shouldered extensive responsibilities and the two squadrons were called upon to attack enemy targets from one end of the Channel to the other, by day and night, moving from airfield to airfield within Southern England.

“In retrospect the lesson of the Whirlwind is clear… A radical aircraft requires either prolonged development or widespread service to exploit its concept and eliminate its weaknesses, Too often in World War II such aircraft suffered accelerated development or limited service, with the result that teething difficulties came to be regarded as permanent limitations.”

[edit] Variants

P.9 prototype

Single-seat twin-engine fighter aircraft prototype. Two built (L6844 and L6845), can be distinguished from later production samples by the mudguards above the wheels (Though the first production sample (P6966) had them as well), the exhaust system and the so-called 'acorn' on the joint between fin and rudder .

Whirlwind I

Single-seat twin-engine fighter aircraft. 400 ordered, 114 built

Whirlwind IA

Single-seat twin-engine fighter-bomber aircraft, fitted with underwing bomb racks. At least 67 conversions made from the original Mk.I fighter.

[edit] Operators

 United Kingdom

• Royal Air Force
  • No. 25 Squadron RAF May 1940 - July 1940, Squadron code 'ZK' (not used on the three Whirlwinds it tested).
  • No. 137 Squadron RAF September 1941 - June 1943, Squadron code 'SF'.
  • No. 263 Squadron RAF July 1940 - December 1943, Squadron code 'HE'.

[edit] Survivors

With the end of production in January 1942, the Whirlwind became another "also-ran." Today none exist, as surviving airframes were scrapped at 5MU - RAF Kemble. Plans for a 2/3 scale replica were marketed for homebuilding in the late 1970s and early '80s as the Butterworth Westland Whirlwind. In 2003, UK aircraft restorer Tony King announced that he would lead a group to build a Westland Whirlwind replica from scratch. Built in aluminium throughout, the full-scale replica was intended to taxi under its own power. Since the project announcement, further work appears to be stymied.^[4]

[edit] Specifications (Whirlwind)

General characteristics

• Crew: One pilot
• Length: 32 ft 3 in (9.83 m)
• Wingspan: 45 ft 0 in (13.72 m)
• Height: 11 ft 7 in (3.53 m)
• Wing area: 250 ft² (23 m²)
• Empty weight: 8,310 lb (3,770 kg)
• Loaded weight: 10,356 lb (4,697 kg)
• Max takeoff weight: 11,410 lb (5,175 kg)

Performance

• Maximum speed: 360 mph (560 km/h)
• Range: 808 miles (1,300 km)
• Service ceiling 30,315 ft (9,240 m)
• Rate of climb: 1.550 ft/min (474 m/min)
• Wing loading: 41 lb/ft² (204 kg/m²)

Armament

• 4x Hispano 20 mm cannon in nose (60 rounds per gun, 240 rounds total)
• 2x 250 lb (115 kg) or 500 lb (230 kg) bombs

[edit] See also

Related development

• Westland Welkin
  

Comparable aircraft

• de Havilland Mosquito
• de Havilland Hornet
• Focke-Wulf Fw 187
• Focke-Wulf Ta 154
• Gloster F.9/37
• Fokker G.1
• XF5F Skyrocket
  

Related lists

• List of aircraft of the RAF
  

[edit] References

[edit] Notes

[edit] Bibliography

[edit] External links

• Westland Whirlwind
• British Aircraft of WW2
• colour profiles

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