https://en.wikipedia.org/wiki/Avro_Manchester
The Avro 679 Manchester was a British twin-engine heavy bomber developed during
the Second World War by the Avro aircraft company in the United Kingdom. Serving
in the Royal Air Force and Royal Canadian Air Force, the Manchester was an
operational failure because of its underdeveloped, underpowered and unreliable
engines. The aircraft was the forerunner of the successful four-engined Avro
Lancaster, which would become one of the most capable strategic bombers of the
war.
The Manchester was originally designed to the Air Ministry Specification
P.13/36; it was the same specification that Handley Page also followed in their
design of the Halifax bomber. Issued in May 1936, Specification P.13/36 called
for a twin-engine monoplane "medium bomber" for "worldwide use", which was to be
bombloads (8,000 lb/3,630 kg) or two 18 in (457 mm) torpedoes. Provision for
catapult assisted takeoff to permit the maximum load was also part of the
specification, although the need for this provision was explicitly removed in
July 1938. Cruising speed was to be a minimum of 275 mph at 15,000 feet. The Air
Ministry had expectations for an aircraft of similar weight to the B.1/35
specification, but being both smaller and faster.
While the Manchester was designed with a twin tail, the first production
aircraft, designated the Mk I, had a central fin added and twenty aircraft like
this were built. They were succeeded by the Mk IA which reverted to the twin-fin
system but used enlarged, taller fin and rudders mounted on a new tailplane,
with span increased from 22 ft (6.71 m) to 33 ft (10.06 m). This configuration
was carried over to the Lancaster, except for the first prototype, which also
used a central fin and was a converted, unfinished Manchester. Avro constructed
177 Manchesters while Metropolitan-Vickers completed 32 aircraft. Plans for
Armstrong Whitworth and Fairey Aviation at Stockport/Ringway to build the
Manchester were abandoned. Fairey's order for 150 Manchesters was replaced by
multiple orders for the Handley Page Halifax.
The Manchester was powered by a pair of Vulture engines; in service these proved
to be extremely unreliable. Aviation author Jon Lake stated of the Vulture: "The
engine made the Manchester mainly notable for its unreliability, poor
performance, and general inadequacy to the task at hand" and attributed the
aircraft's poor service record to the engine troubles.
"I was one of the six original pilots to have flown with the first Manchester
squadron. That was a disaster. The aircraft itself, the airframe, had many
shortcomings in equipment in the beginning, but as we found out Avro were
excellent in doing modifications and re-equipping the aeroplane. The engines
never were and never did become reliable. They did not give enough power for the
aeroplane, so we ended up with two extremely unreliable 1,750 hp engines having
to haul a 50,000-pound aircraft. We should really have had 2,500 hp engines. You
felt that if you'd lost one, that was it, you weren't coming home. It didn't
matter if you feathered the propeller or not. There was only one way you went
and that was down. I have seen an aircraft doing a run up on the ground and have
two pistons come right out through the side of the engine. The original bearings
were made without any silver as an economy measure, so they weren't hard enough.
The bearings would collapse the connecting rod and the piston would fling out
through the side of the engine and bang! Your engine just destroyed itself.
Role
Heavy bomber
Manufacturer
Avro
First flight
25 July 1939
Introduction
November 1940
Retired
1942
Primary users
Royal Air Force
Royal Canadian Air Force
Produced
Number built
202
Developed into
Avro Lancaster
On 13 April 1941, all Manchesters were temporarily grounded due to a higher than
expected number of engine bearing failures; on 16 June 1941, a second grounding
of the type was ordered due to continuing engine troubles. The unservicability
of the Vulture engine forced squadrons to make use of obsolete bombers such as
the Handley Page Hampden in its place. Upon the restart of operations in August
1941, additional issues with the aircraft were encountered; the problems
included excessive tail flutter, hydraulic failures, and faulty propeller
feathering controls. Production of the Manchester was halted in November 1941,
by which point a total of 209 aircraft had entered service with the RAF. A total
of eight bomber squadrons were equipped with the type, it also served in two
further squadrons and also saw use by RAF Coastal Command.
The 193 operational Manchesters flew 1,269 sorties with Bomber Command, dropping
1,826 tons (1,657 tonnes) of bombs and lost 78 aircraft in action, flying its
last operation against Bremen on 25 June 1942. A further 45 were non-operational
losses of which 30 involved engine failure. The Manchester was withdrawn from
operations in mid-1942 in favour of more capable aircraft. Its final role in RAF
service was as instructional trainers for converting crews to the RAF's new
Lancaster bombers; the Manchester and Lancaster shared nearly identical crew
positions and fuselages. The type persisted in use for training purposes into
1943 before being completely retired.
Specifications (Manchester Mk I)
General characteristics
Crew: 7
Length: 70 ft (21.34 m)
Wingspan: 90 ft 1 in (27.46 m)
Height: 19 ft 6 in (5.94 m)
Empty weight: 31,200 lb (14,152 kg)
Max. takeoff weight: 50,000 lb (22,680 kg)
each
Performance
Maximum speed: 265 mph (230 kn, 426 km/h) at 17,000 ft (5,180 m)
Range: 1,200 miles (1,930 km) with maximum bomb load of 10,350 lb (4,695 kg)
Service ceiling: 19,200 ft (5,852 m)
Armament
dorsal (2) and tail (4) turrets)
Bombs: 10,350 lb (4,695 kg) bomb load
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