The Vickers Wellesley was one of two designs proposed by Vickers-Armstrongs Ltd to meet the requirements of the Air Ministry’s Specification G.4/31 in 1931.
This specification sought a versatile aircraft capable of fulfilling roles such as torpedo bombing. Alongside the Wellesley, Vickers-Armstrongs also developed the Type 253 biplane for the same purpose. The Type 253 advanced to the prototype stage and was subsequently ordered in a quantity of 150 units.
Parallel to the Type 253, Vickers embarked on a private venture with the Type 246, which was more aligned with the role of a light bomber, even though there was no specific requirement for such an aircraft at that time. The Type 246, which eventually became known as the Wellesley, completed its first flight on June 19th, 1935.
RAF Bomber Command
In the early 1930s, the Wellesley was developed to meet the requirements of Specification G.4/31. The Vickers Type 253 biplane was an initial version of this aircraft, featuring a revolutionary geodesic airframe and sharing many characteristics with the later models.
The Air Ministry found the Type 253 to be the most promising submission, leading to an order for 150 units. Concurrently, Vickers independently developed the Type 256 monoplane. Following successful flight tests of this model, the original order for the Type 253 was redirected to the Type 256.
Most of the Wellesleys produced were assigned to the Royal Air Force (RAF), with six squadrons within RAF Bomber Command operating the aircraft at its operational peak.
A notable demonstration of the Wellesley’s capabilities occurred in early November 1938, when three aircraft completed a non-stop flight from Ismailia, Egypt, to Darwin, Australia. This 7,162-mile (11,526 km) journey set a world distance record.
Although deemed obsolete by the onset of the Second World War and thus unsuitable for the European theater, the Wellesley saw action in desert regions, including East Africa, Egypt, and the Middle East. The aircraft’s operational tenure with the RAF concluded in September 1942, when 47 Squadron ceased using it for maritime reconnaissance missions.
Maiden Flight From Brooklands
The origins of the Wellesley can be traced back to the early 1930s when Vickers shifted its focus to fixed-wing aircraft following its exit from airship production. During this period, many of Vickers’ designs, often responses to Air Ministry specifications, featured a conventional biplane structure.
These designs, larger and equipped with more powerful engines than many contemporary aircraft, were mostly conceptual but incorporated the innovative work of Barnes Wallis, who used light alloy structures to reduce weight without sacrificing strength.
In 1931, the Air Ministry issued Specification G.4/31 for a versatile aircraft capable of level bombing, army cooperation, dive bombing, reconnaissance, casualty evacuation, and torpedo bombing. Vickers responded eagerly, tasking its design team to develop a suitable aircraft.
The team came up with three designs: two monoplanes with different engines, and a biplane known as the Vickers Type 253. In November 1931, these designs were submitted to the Air Ministry, which accepted the Type 253 and awarded a development contract to Vickers in April 1932.
While the Type 253 prototypes were being built, Vickers’ design office independently continued to develop a monoplane to meet the same specification. This monoplane featured a geodesic airframe, drawing from Wallis’ earlier work on the R100 airship.
Aviation author C. F. Andrews noted this approach marked a significant departure from the era’s norms, largely unchanged since World War I, as it offered exceptional strength-to-weight ratios. The Type 253 also incorporated aspects of this structural design, though not as extensively as the monoplane.
Upon completion, the Type 253 prototypes were put through competitive testing against several rivals, including the Fairey G.4/31, Westland PV-7, Handley Page HP.47, Armstrong Whitworth A.W.19, Blackburn B-7, Hawker P.V.4, and the Parnall G.4/31. This testing process revealed that the Type 253 was the superior design, leading to Vickers receiving an order for 150 aircraft.
Chief Test Pilot
The privately developed monoplane, known internally as the Vickers Type 246, continued to progress. On June 19, 1935, it completed its first flight from Brooklands, piloted by Vickers’ Chief Test Pilot J “Mutt” Summers.
After this successful flight, the aircraft was presented to the Royal Air Force (RAF). The Type 246 was designed primarily as a bomber, focusing on performance rather than the multi-role capability outlined in the original specification. On July 23, 1934, the G.4/31 monoplane suffered a crash and was subsequently rebuilt as a pre-production version of the Type 246 to aid in the development of the latter.
According to aviation author C. F. Andrews, the development of the Wellesley required an unusually high level of engineering resources, primarily due to its innovative airframe structure.
This necessitated extensive metallurgical research and the construction of multiple structural test rigs to confirm the airframe’s strength. The production of the Wellesley’s unique curved frames for its geodesic structure called for the creation of new powered machinery, significantly speeding up production compared to the manual methods initially used in the pre-production stage.
This machinery later found applications in the production of various wartime and postwar aircraft, including the Vickers VC10 jetliner. Andrews also notes that Vickers had explored the possibility of using stressed-skin construction in the Wellesley’s design.
Going into Production
In September 1935, an initial order for 96 Type 246 aircraft, later known as the Wellesley, replaced the previous order for the Type 253. The contract was updated in August 1936 to specify that the production model should be equipped with the Bristol Pegasus XX radial engine.
The first production Wellesley took off for its maiden flight from Brooklands on 30 January 1937 and was subsequently sent to RAF Martlesham Heath for type tests on 18 March.
The RAF eventually placed an order for a total of 176 Wellesley aircraft under the newly established Specification 22/35. Mass production began in March 1937, and over the next 14 months, all units were manufactured. By March 1938, 176 Wellesleys were in service, with 57 stationed at home bases.
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Around this time, the RAF explored various improvements for the Wellesley, including adding a third crew member as a navigator and modifying the bomb-aimer’s position. The aircraft initially had issues with vibration when the bomb-container doors were open, leading to the removal of these doors with minimal impact on drag.
Additionally, most Wellesleys were built with a revised wing design for enhanced strength, and eight early models were retrofitted with this improved wing.
The Wellesley was a single-engine monoplane featuring a high aspect ratio wing of 8.83 and a manually operated, retractable undercarriage. Due to uncertainty about how the geodetic structure would handle a bomb bay, the Wellesley carried its bombs in streamlined panniers under the wings.
The Wellesley Mk I featured two cockpits, but in the unofficially designated Mk II version, the pilot’s canopy was extended to cover the navigator/bomb aimer’s position embedded in the fuselage. The gunner maintained a separate canopy. Flight controls were provided only for the pilot, and the aircraft was equipped with a three-axis autopilot.
Vickers Wellesley Operational History
The RAF welcomed its first Wellesleys in April 1937, with the aircraft initially serving with No. 76 Squadron RAF at Finningley. Eventually, six RAF Bomber Command squadrons in the UK were equipped with the Wellesley.
Five of these aircraft, modified to accommodate three crew members for long-range missions, were assigned to the RAF Long-Range Development Flight. These modifications included the installation of Pegasus XXII engines and additional fuel tanks.
On November 5, 1938, a notable long-distance flight was undertaken by three Wellesleys, led by Squadron Leader Richard Kellett, flying non-stop from Ismailia, Egypt, to Darwin, Australia, covering 7,162 miles (11,526 km) and setting a world distance record.
Despite all three aircraft breaking the record, one landed in West Timor, 500 miles (800 km) short of Darwin. This record remained unbroken until November 1945 and still stands as the longest flight by a single piston-engine aircraft.
By the time World War II began, the Wellesley had been phased out by all UK-based squadrons, with only four remaining in Britain. However, three squadrons in the Middle East continued to operate the type.
The Wellesley was replaced in RAF Bomber Command by more advanced twin-engined bombers like the Handley Page Hampden, Armstrong Whitworth Whitley, and the Vickers Wellington, the latter sharing the geodesic structure with the Wellesley.
Vickers Wellesley Outdated
After Italy entered the war in June 1940, the remaining Wellesley squadrons took part in the East African Campaign against Italian forces in Eritrea, Ethiopia, and Somaliland.
Despite being outdated, the Wellesley was a significant part of the British Commonwealth bomber forces in the region, carrying out raids mainly in Eritrea and northern Ethiopia.
The first bombing mission by Sudan-based Wellesleys was on June 11, 1940, against Asmara in Eritrea. They faced their first air combat shortly after, when Italian pilot Capitano Mario Visintini, in a Fiat CR.42 Falco, shot down a Wellesley, marking his first of 16 air victories in Eastern Africa.
The Wellesleys, often operating without fighter escorts, were vulnerable to Italian CR.42 fighters but continued to participate in bombing missions, including an attack on Addis Ababa from Aden in August
. They remained active in East Africa until November 1941, when the last Italian stronghold, Gondar, fell. The final unit operating the Wellesley, 47 Squadron, was then reassigned to maritime reconnaissance duties over the Red Sea until September 1942.
While the Wellesley itself was not a major combat aircraft, the design principles it tested greatly influenced the development of the Wellington medium bomber, a key asset for Bomber Command in the early European war years. Additionally, in February 1940, three Wellesleys were sold to Egypt for use by the Royal Egyptian Air Force.
177 Vickers Wellesley Were Built
In 1938, the Wellesley marked a significant achievement when three Mk Is surpassed the world record for long-distance flight. Departing from Ismailia, Egypt on November 5, the trio embarked on a non-stop journey covering 7,159 miles to Darwin, Australia.
Although one aircraft was forced to land in Kupang, Indonesia, due to low fuel, it still managed to break the existing record by about 450 miles. The remaining two Wellesleys completed the journey to Australia on November 7, 1938, setting a new record by flying 950 miles further than the previous one, just over 48 hours after takeoff.
Though only 177 Wellesleys were built, the aircraft’s contribution to World War II air warfare was not its most notable legacy. Instead, it was instrumental in introducing Barnes Wallis’s geodetic construction method. This innovative approach allowed for the creation of strong yet lightweight aircraft, a significant advancement in aeronautical engineering.