In October 1932, the British Air Ministry invited Vickers to tender for the recently issued Specification B.9/32, which sought a twin-engine medium daylight bomber.

[3] Early on, Vickers' chief structures designer Barnes Wallis proposed the use of a geodetic airframe, inspired by his previous work on airships and the single-engined Wellesley light bomber.

[4] This strength allowed for the structure design to be further developed to reduce the size of individual members and adopt simplified standard sections of lighter construction.

[6] Other refinements of the design had also been implemented and approved, such as the adoption of variable-pitch propellers, and the use of Vickers-produced gun turrets in the nose and tail positions.

[7] The proposal had also been developed further, a mid-wing arrangement was adopted instead of a shoulder-mounted wing for greater pilot visibility during formation flight and improved aerodynamic performance, as well as a substantially increased overall weight of the aircraft.

The cause was the failure of the elevator's horn balance due to excessive slipstream exposure, leading to the aircraft inverting and rapidly descending into terrain.

The production model Wellington was a complete redesign, resulting in a lengthened nose for turret and bomb aimer's position, a reshaped elevator and deepened fuselage which accommodated a larger bombload and the increased crew from four to five members.

[14] Flight trials with L4212 confirmed the aerodynamic stability initially encountered by K4049, but also revealed the aircraft to be nose-heavy during dives, which was attributed to the redesigned elevator.

[17] The geodetic design took longer to build than comparable aircraft using the more conventional monocoque approach, leading to some criticism of the Wellington.

[17] In addition it was difficult to cut holes in the fuselage for access or equipment fixtures; to aid manufacturing, the Leigh light was deployed through the mounting for the absent FN9 ventral turret.

[17] In October 1943, as a propaganda and morale-boosting exercise, workers at Broughton gave up their weekend to build Wellington number LN514 rushed by the clock.

The Wellington was initially outnumbered by the Handley Page Hampden (also ordered by the Ministry to B.9/32) and the Armstrong Whitworth Whitley (to B.34/3 for a 'night' bomber) but outlasted both rival aircraft in service.

The principal change on this model was the adoption of the Merlin engine in place of the Pegasus XVIII; other modifications included hydraulic and oxygen system revisions along with the installation of cabin heating and an astrodome.

[10] Recognisable characteristics of the Wellington include the high aspect ratio of its tapered wing, the depth of its fuselage and the use of a tall single fin on its tail unit, which reportedly aided in recognition of the type.

[10] The Wellington could be fitted with dual flight controls, and specialised dual-control conversion sets were developed for the purpose of performing training upon the type.

[15] The squadrons were critical of the ventral turrets; when extended they slowed the aircraft by 10 mph, the single narrow window pane limited visibility and sometimes froze in place and had to be jettisoned.

The construction proved to be compatible with significant adaptations and alterations including greater all-up weight, larger bombs, tropicalisation and long-range fuel tanks.

[24] The metal lattice gave the structure considerable strength, with any stringer able to support a portion of load from the opposite side of the aircraft.

149 Squadrons, alongside a number of Bristol Blenheim aircraft, performed the first RAF bombing raid of the war, against German shipping at Brunsbüttel.

[29] Having been alerted by radar, Luftwaffe fighter aircraft intercepted the incoming bombers near to Heligoland and attacked the formation for much of the way home.

[29][30] The action at Heligoland highlighted the Wellington's vulnerability to attacking fighters, possessing neither self-sealing fuel tanks nor sufficient defensive armament.

[29][30] Unescorted day bombing was abandoned and Bomber Command decided to use the Wellington force to attack German communications and industrial targets instead.

[31] A unique feat for the type occurred on 23 December 1944 when a Me 163 Komet was shot down by rear gunner Gerry Elsyon, who was awarded the DFM.

[29] The Mark IC in Coastal had a endurance of over ten hours at a cruising speed of 125 knots carrying 1,500 lb (680 kg) of bombs or depth charges.

In 1944, Wellingtons of Coastal Command were sent to Greece and performed various support duties during the British intervention in the Greek Civil War.

While the Wellington was superseded in the European Theatre as more four engined bombers arrived in service, it remained in operational service for much of the war in the Middle East and still formed a key part of the RAF's Mediterranean forces as the allies moved into Italy, with some still serving in March 1945 carrying out bombing raids and dropping supplies to partisans across Southern Europe.

[35] The hoop was an aluminium coil in an aerodynamic balsa case; turrets were faired over and unnecessary equipment removed to reduce weight.

This prototype substituted batteries for the engine and generator setup to reduce weight and this carried forward into production Leigh light-equipped Wellingtons [36] Together with accurate radar altimeters, Wellingtons could fly safely down to 50 ft, illuminating the target submarine at around half a mile away just as the air-to-surface-vessel (ASV) radar lost the target among returns from the water's surface.

Built at Brooklands and first flown in November 1939, this aircraft took part in the RAF's daylight bombing raids on Germany early in the Second World War but later lost power during a training flight on 31 December 1940 and ditched in Loch Ness.

A new Wellington exhibition featuring N2980 was officially opened by Robin Holmes (who led the recovery team), Penelope Keith (as trustee of Brooklands Museum), Norman Parker (who worked for Vickers) and Ken Wallis (who flew Wellingtons operationally) on 15 June 2011, the 75th anniversary of the first flight of the type's effective prototype in 1936.