- Yes
- No
Introduction: The Avro Manchester is one of Britain’s forgotten types, due to various reasons. To begin with, it had a very short service life, caused by serious reliability and developmental issues that would ultimately lead to its downfall. Despite this, the aircraft proved to have good roots, and it would be modified to become one of Britain’s most famous aircraft.
Background: In the mid-1930’s, the Air Staff believed that the heavy bomber would be the most effective weapon for both offensive and defensive operations. This was the time where it was believed that the “bomber would always get through”, which made it an unstoppable strike weapon that could solve many issues. This was also a time of rapid technological advance, with engines increasing in both size and power, and airframe manufacturing techniques making leaps and bounds from design to design. It was thus found necessary to design a new generation of bomber which would carry heavier loads than existing types over longer distances. The Air Staff had also sent fact finding missions to the US, and they were impressed by the projects going on at that point, with aircraft such as the B-17 and B-18 being drawn up and prepared for testing at this point. The UK issued two requirements: B.12/36 and P.13/36 were both issued in order to provide a wide-ranging modernisation to the British bomber fleet. For B.12/36, Shorts and Supermarine were chosen to produce aircraft, their designs becoming the Stirling and the Type 317 respectively. Meanwhile, P.13/36 would ultimately lead to the Manchester and Halifax.
P.13/36 ran concurrently with the B.12/36 requirement, and aimed to achieve a relatively similar requirement, albeit on a smaller platform. In some documentation, it was referred to as a medium bomber requirement, though for all intents and purposes, it was a heavy bomber requirement. The aircraft was intended to be around the same weight as the Vickers Warwick, which was then in development, although smaller in size and faster. The requirement called for a maximum bombload of 8,000lb (3,629kg) with a range of at least 2,000 miles (3,219km) with this load, and 3,000 miles (4,828km) using a lighter load. A high cruising speed and altitude was required in order to provide the best survivability over enemy territory, with a speed of at least 275mph (442km/h) at 15,000ft. Survivability also depended on self-defence, and the aircraft was to be provided with all-round cover through the use of machine guns. The weapons load was 8,000lb (3,629kg), with the option for two 18in (45.7cm) torpedoes included into the requirement. Additionally, catapult-assisted take-off was proposed. P.13/36 was issued on the 5th November 1936 to Avro, Boulton Paul, Bristol, Fairey, Handley Page, Hawker, Shorts and Vickers. Out of these companies, Avro and Handley Page were chosen to proceed with their designs.
Description: Avro’s design was designated the Type 679, which had begun its design phase prior to the requirement. It was powered by two Rolls-Royce Vultures and had a twin fin, thus setting the basic lines for what would become the Manchester, despite being quite different in the initial phase. The Tender Conference was held on the 10th of February 1937, with Avro placing first, with two prototypes being ordered. However, the Air Ministry was quite anxious to get the 679 into production, due to ongoing event on the Continent, and it was thus ordered “straight off the drawing board.” The mock-up conference was held on the 4th of May of that same year. As development progressed, requirements changed, causing delays and adding costs. For instance, the catapult and torpedo requirements were dropped, which mean that the structures were now fitted with equipment which now served no purpose and simply added weight, yet would be expensive to remove (£50,000 was quoted), and removal would only add delays. The prototype first flew on the 25th of July, 1939. Flight trials revealed further issues; the Manchester exhibited poor take-off performance and had poor directional stability. The latter was rectified by adding a central fin above the gunner’s position, but weight remained an issue for the Manchester. It was found that as development progressed, weight kept increasing; in February 1939, it was found that the weight had already increased by 4,485lbs (2,03kg) and another 550lb (249kg) was yet to be added. Avro took drastic measures to reduce weight, including the replacement of the metal bomb bay doors with wooden ones, reducing the thickness of the covering skin, increasing wing span from 80 ft to 90ft (24.38m to 27.43m) amongst other changes. Even still, Avro had to re-stress the aircraft six times.
Further issues were caused by the problematic Rolls-Royce Vultures, which had woeful reliability. This caused Rolls-Royce to abandon the engine completely in 1941, instead focusing on the Merlin and Griffon, which made sense for them from a production standpoint, but effectively doomed the Manchester as a viable service aircraft. This came at the unfortunate moment at which production was ramping up, and would force Avro to cut production in 1941 after just 200 aircraft were made. There were proposals to fit the aircraft with new engines, such as the Napier Sabre or Bristol Centaurus, but these never came to pass. By this point the issues which had caused the failure of both the Manchester and Warwick B.MK.I had basically put the Air Staff off twin-engined heavy bomber aircraft entirely. This was mainly due to poor survivability and engine-out performance. It was due to this reason why the Manchester’s stablemate, the H.P.56 was never built in its initial twin-engine form, instead being rebuilt into the four-engined Halifax, due to the aforementioned reasons. Avro thus resorted to building a four-engined variant of the Manchester, which, whilst facing some initial opposition, would eventually become one of Britain’s most legendary aircraft. In the meantime, the Air Ministry was looking to up-arm the defensive armament of the existing bomber types in service, these being the Manchester, Halifax and Stirling, with 20mm Hispano cannons. For the Manchester, this involved a complete redesign of the rear 2/3s of the aircraft, with a widened section to fit the new quad-20mm turret, but this program never left the drawing board.
Service: The Manchester had a very limited service life due to the reasons mentioned previously. The first aircraft entered service in 1940, with the first operational use occurring in 1941 against Brest. On the 30th of May 1942, 45 Manchesters were used in the First 1000 Bomber Raid on Cologne. The type was retired from frontline service that year, being used as a trainer up until 1943, when more capable types replaced it.
Performance:
Spoiler
| Span: | 90ft 1in (27.46m) |
|---|---|
| Length: | 68ft 10in (20.98m) |
| Wing Area: | 1,131sq ft (105.07sq m) |
| All-Up-Weight | 45,000lb (20,412kg) |
| Powerplant: | 2x 1,760hp (1,312kW) Rolls-Royce Vulture I |
| Max Speed/Heigh | 265mph (426km/h) at 17,000ft (5,182m) |
| Armament: | 8,000lb (3,629kg) normal bombload, |
10,350lb (4,695kg) maximum bombload,
8x 0.303in (7.7mm) machine guns|
Conclusion: The Manchester was the byproduct of an unfortunate series of outdated requirements, ill-fated decisions and unreliable parts, which all contributed to give the aircraft a short and unfortunate stay in service. Despite this, the aircraft was important in British aviation history for two reasons. Firstly, it provided the RAF with a taste of modern aircraft design that would set the foundation of future projects, and inform project managers on decision making and design choices. Secondly, it was used as a basis for the Lancaster bomber, which proved to be one of the most reliable and important aircraft of the RAF in the Second World War. It can therefore be argued that the success of the Lancaster was built upon the failure of the Manchester, and it can thus be concluded that its failure not only made a way for its success, but also informed the designers and planners in both the industry and the RAF on how to design and operate heavy bomber aircraft, thus creating the recipe of success that would lead to the Lancaster.
Sources:
Spoiler
“British Secret Projects 4: Bombers 1935 to 1950” by Tony Buttler
https://www.baesystems.com/en/heritage/avro-679-manchester
https://the-past.com/shorts/ideas/back-to-the-drawing-board-the-avro-manchester/