The Avro Lancaster started life as the Avro Manchester, a design to a 1936 Air Ministry specification for a twin engined medium bomber. Oddly the specification also included a requirement that the aircraft be able to carry out dive-bombing at angles of up to 30-degees and the ability to launch torpedoes. Featuring a huge unobstructed bomb-bay and two compact yet very powerful Vulture engines with an X cylinder and crankshaft array, the Manchester was a promising concept.

Prototype Manchester

The Vulture engines were the key to the design and also its eventual downfall. Two Rolls Royce Peregrine engines joined together (one inverted on top of the other) driving a single crankshaft and with an intricate lubricating system it was a complex engine that suffered from lack of development. Rolls Royce, eager to produce as many Merlin engines as possible for other aircraft, could not devote the effort necessary to perfect the Vulture and the result was an engine plagued with problems, including overheating, seizure and a tendency to catch fire.

Delays to the first flight of the Manchester were caused by continual design changes ordered by Rolls Royce as they modified the Vulture, however the aircraft flew for the first time on 25 July, 1939. Although the engines performed well, the aircraft suffered from poor control and a long take-off run even though it was lightly loaded.

Ironically at the same time as the Manchester was being developed, the Germans were working on their He 177, a bomber of similar proportions powered by two engines each consisting of two Daimler Benz twelve cylinder engines connected by a common crankshaft in an arrangement almost identical to the Rolls Royce Vulture. Like the Manchester, the He 177 was a promising design, hampered by immature engines. It eventually went into service but soon became known as a "flying coffin", with a tendency for its engines to catch fire and burn through the mainspar. Oddly, it too was designed to a specification requiring it to be able to dive bomb - a legacy of the accuracy achieved by the Stuka that so impressed Luftwaffe senior officers that they insisted that almost every aircraft capable of carrying bombs should also be able to deliver them in a steep dive.

He 177 Grief

Realising the limitations of the Vulture, Avro produced revised designs for the Manchester using other engines such as the Napier 24-valve radial and a four-engine version with Merlins. The four engine version offered advantages including commonality of components and proven engines that were already showing the potential for greater power output than could be expected from the Vultures. It was decided to continue design studies in case the problems with the Vulture continued, concentrating on the four engined version.

After tests with the prototype Manchester changes were made to the second aircraft including increasing the wingspan and adding a small fin on the rear fuselage. The increased wing span shortened the take-off run and increased the bomb load, however stability and control remained a problem. Stability in the bombing run was proving to be crucial, as the prototype showed a pronounced tendency to "waddle" in level flight. The additional vertical stabiliser improved this slightly but test crews still regarded it as a difficult aircraft to fly with any precision.

Manchester I with central fin

In August 1940, the first production aircraft was flown to Boscombe Down for tests. The engines were de-rated in an effort to improve reliability and the first Manchesters were soon cleared for service with No 207 Squadron at Waddington. The squadron's work-up to operational readiness was hampered by the unreliability of the Vulture engines and concern was voiced when the aircraft was used in the dive-bombing role originally called for by the Air Ministry. Continued problems with the engines meant further groundings and Avro formally proposed that a new version be built and tested.

Avro's head designer Roy Chadwick, had already done most of the work on the new design. Keeping the Manchester's spacious fuselage and increasing the original 82ft wingspan to 102ft (31.09 m), he replaced the Vulture engines with four Rolls-Royce Merlins. This design, given the temporary name of Manchester III, first flew on January 9th, 1941 and immediately demonstrated its potential.

Manchester III

The Manchester's operational debut was made during a raid on German Capital ships in Brest when 6 aircraft from No 207 Squadron attacked a cruiser with 500lb armour-piercing bombs. Two nights later, the squadron attacked Germany for the first time when Cologne was the target. By April 1941, a second Manchester squadron was formed ( No 97) and aircraft from both units joined Bomber Command raids in the coming months.

During the summer of 1941, No 61 Squadron became the third Manchester squadron and the first to receive a revised version featuring larger fins which cured the poor handling of the earlier aircraft. At the same time, the reliability of the Vultures was increased to such an extent that no more Manchesters were being lost to mechanical failure on a percentage basis than any other bombers. However the limitations of the twin engined design were apparent and the advantages of switching to the four engined version with its associated growth potential had by now become clearly obvious.

Manchester II with increased fin area

By the end of 1941, Manchesters were regularly in operations over Germany with bomb loads of up to 8,000lbs. Most ops however, were restricted to attacking German naval vessels in the Channel ports with armour-piercing bombs. In February 1942, four Manchester squadrons were airborne over the Channel attempting to stop the Gneisenau and Scharnhorst from escaping from Brest in the famous 'Channel Dash', but the poor weather prevented them from finding the convoy. Two weeks later however, Manchesters were among a raid on the Gneisenau which was now berthed in Kiel, attacking the warship with armour-piercing bombs.

Despite the growing successes with the revised Manchester, the advantages of switching production to the new four engined version, now named the Lancaster, were clearly obvious and production was ceased after only 200 of the original order for 1200 were produced.

Avro Lancaster

By the middle of 1942, Manchesters were being replaced by Lancasters in Bomber Command and a single aircraft from No 83 Squadron made the final operational Manchester flight during an attack on 26th June 1942 on Bremen.