Armstrong Whitworth Whitley

The Armstrong Whitworth A.W.38 Whitley was one of three British twin-engine, front line medium bomber types in service with the Royal Air Force at the outbreak of the Second World War (the others were the Vickers Wellington and the Handley Page Hampden). It took part in the first RAF bombing raid on German territory and remained an integral part of the early British bomber offensive until the introduction of four-engined "heavies". Its front line service included maritime reconnaissance with Coastal Command and the second line roles of glider-tug, trainer and transport aircraft. The aircraft was named after Whitley, a suburb of Coventry, home of one of Armstrong Whitworth's plants.


Armstrong Whitworth Whitley
Class Aircraft
Type Bomber
Manufacturer Armstrong Whitworth
Production Period 1937 - 1946
Origin United Kingdom - UK (Great Britain)
Country Name Origin Year
United Kingdom - UK (Great Britain) 1936
Country Name Operational Year Retirement Year
United Kingdom - UK (Great Britain) 1937 1945 View
ManufacturerName Production From Production To Quantity
Armstrong Whitworth 1937 1946 1814 View

The Whitley was designed by John Lloyd, the Chief Designer of Armstrong Whitworth Aircraft to meet Air Ministry Specification B.3/34 issued in 1934 for a heavy night bomber. The AW.38 design was a development of the Armstrong Whitworth AW.23 bomber-transport design that had lost to the Bristol Bombay for specification C.26/31, partly due to its Armstrong Siddeley Tiger engines. The Whitley carried a crew of five and was the first aircraft serving with the RAF to have a (semi-)monocoque fuselage, using a slab-sided structure which eased production. As Lloyd was unfamiliar with the use of flaps on a large heavy monoplane, they were initially omitted. To compensate, the mid-set wings were set at a high angle of incidence (8.5°) to confer good take-off and landing performance. Although flaps were included late in the design stage, the wing remained unaltered. As a result, the Whitley flew with a pronounced nose-down attitude, resulting in considerable drag. This "nose down" attitude was also seen in the design of the Armstrong Whitworth Ensign pre-war airliner.

The first prototype Whitley Mk I (K4586) flew from Baginton airfield on 17 March 1936, piloted by the Armstrong Whitworth Chief Test Pilot Alan Campbell-Orde and was powered by two 795 hp (593 kW) Armstrong Siddeley Tiger IX radial engines. The second prototype was powered by more powerful Tiger XI engines. Owing to the urgent need to replace biplane heavy bombers in service with the RAF, an order for 80 aircraft had been placed in 1935, "off the drawing board". These had medium-supercharged engines and manually operated, drum magazine single machine guns fore and aft. After the first 34 aircraft had been built, the engines were replaced with more reliable two-stage supercharged Tiger VIIIs, resulting in the Whitley Mk II, that completed the initial order. One Whitley Mk II, K7243, was used as a test bed for the 1,200 hp 21-cylinder radial Armstrong Siddeley Deerhound engine, first flying with the Deerhound on 6 January 1939. The replacement of the manually operated nose turret, with a powered Nash & Thomson turret and a powered retractable two-gun ventral "dustbin" turret, resulted in the Whitley Mk III. The turret was hydraulically powered but it was hard to operate and added considerable drag.

While the Tiger VIIIs used in the Whitley Mks II and III were more reliable than those used in early aircraft, the Whitley was re-engined with Rolls-Royce Merlin engines in 1938, giving rise to the Whitley Mk IV. The new engines produced greatly improved performance and the decision was made to introduce a series of other minor improvements to produce the Whitley Mk V. The fins were modified, leading edge de-icers were fitted, manually operated tail and retractable ventral turrets were replaced with a Nash & Thompson powered turret equipped with four .303 in (7.7 mm) Browning machine guns and the rear fuselage was extended by 15 in (381 mm) to improve the field of fire. The Mk V was the most numerous version of the Whitley, with 1,466 built until production ended in June 1943.

Early marks of the Whitley had bomb bay doors—the eight bays were in fuselage compartments and wing cells—that were held shut by bungee cords and opened by the weight of the bombs as they fell on them. The short and unpredictable delay for the doors to open led to highly inaccurate bombing. The Mk.III introduced hydraulically actuated doors which greatly improved bombing accuracy. To aim bombs, the bomb aimer opened a hatch in the nose of the aircraft, which extended the bomb sight out of the fuselage but the Mk IV replaced this hatch with a slightly extended transparency, improving crew comfort. The bomb aimer position was in the nose with a gun turret above. The pilot and second pilot/navigator sat side by side in the cockpit. The navigator rotated to use the chart table behind and the wireless operator was further back. The fuselage aft of the wireless operator was divided horizontally by the bomb bay. Behind the bomb bay was the main entrance and aft of that the rear turret.

The Whitley first entered service with No. 10 Squadron in March 1937, replacing Handley Page Heyford biplanes. By the outbreak of the Second World War, seven squadrons were operational, the majority flying Whitley IIIs or IVs, as the Whitley V had only just been introduced. With the Handley Page Hampden and the Vickers Wellington, Whitleys bore the brunt of the early fighting and saw action on the first night of the war, when they dropped propaganda leaflets over Germany. Among the many aircrew who flew the Whitley in operations over Germany, was Leonard Cheshire who spent most of his first three years at war flying Whitleys. Unlike the Hampden and Wellington—which met specification B.9/32 for a day bomber—the Whitley was always intended for night operations and escaped the early heavy losses received in daylight raids on German shipping, early in the war. With Hampdens, the Whitley made the first bombing raid on German soil on the night of 19/20 March 1940, attacking the Hornum seaplane base on the Island of Sylt. Whitleys also carried out Operation Haddock the first RAF raid on Italy, on the night of 11/12 June 1940.

As the oldest of the three bombers, the Whitley was obsolete by the start of the war, yet over 1,000 more were produced before a suitable replacement was found. A particular problem with the twin-engine aircraft, was that it could not maintain altitude on one engine. Whitleys flew 8,996 operations with RAF Bomber Command, dropped 9,845 tons (8,931 tonnes) of bombs and 269 aircraft were lost in action.

The Whitley was retired from front line service in late 1942 but it continued to operate as a transport for troops and freight, as well as for paratroop training and towing gliders. No. 100 Group RAF used Whitleys to carry airborne radar and electronic counter-measures. In February 1942, Whitleys carried the paratroops who participated in the Bruneval raid (Operation Biting) in which German radar technology was captured from a German base on the coast of France.

The British Overseas Airways Corporation operated 15 Whitley Mk Vs converted into freighters in 1942. Running night supply flights from Gibraltar to Malta, they took seven hours to reach the island, often landing during air attacks. They used large quantities of fuel for a small payload and were replaced in August 1942 by the Lockheed Hudson, with the 14 survivors being returned to the Royal Air Force. Long-range Coastal Command Mk VII variants, were among the last in front-line service, with the first kill attributed to them being the sinking of the German U-boat U-751, on 17 July 1942, in combination with a Lancaster heavy bomber. Having evaluated the Whitley in 1942, the Fleet Air Arm operated a number of modified ex-RAF Mk VIIs from 1944–46, to train aircrew in Merlin engine management and fuel transfer procedures.

Role Night bomber
National origin United Kingdom
Manufacturer Armstrong Whitworth Aircraft
Designer John Lloyd
First flight 17 March 1936
Introduction 1937
Retired 1945
Primary user Royal Air Force
Number built 1814
Developed from Armstrong Whitworth AW.23


General characteristics

  • Crew: 5
  • Length: 70 ft 6 in (21.49 m)
  • Wingspan: 84 ft (25.60 m)
  • Height: 15 ft (4.57 m)
  • Wing area: 1,137 ft (106 m)
  • Empty weight: 19,300 lb (8,768 kg)
  • Max takeoff weight: 33,500 lb (15,196 kg)
  • Powerplant: 2 x Rolls-Royce Merlin X liquid-cooled V12 engine, 1,145 hp (855 kW) each

Performance

  • Maximum speed: 200 knots (230 mph, 370 km/h) at 16,400 ft (5,000 m)
  • Combat radius: 1,430 nm (1,650 mi, 2,650 km)
  • Ferry range: 2,100 nm (2,400 mi, 3,900 km)
  • Service ceiling 26,000 ft (7,900 m)
  • Rate of climb: 800 ft/min (4.1 m/s)
  • Max wing loading: 29.5 lb/ft (143 kg/m)
  • Minimum power/mass: 0.684 hp/lb (112 W/kg)

Armament

  • Guns:
    • 1 x .303 in (7.7 mm) Vickers K machine gun in nose turret
    • 4 x .303 in Browning machine guns in tail turret
  • Bombs: Up to 7,000 lb (3,175 kg) of bombs in the fuselage and 14 individual cells in the wings, typically including
    • 12 x 250 lb (110 kg) and
    • 2 x 500 lb (230 kg) bombs
    • Bombs as heavy as 2,000 lb (907 kg) could be carried

End notes