The Avro Type 557 Ava was a British twin-engined

biplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...

torpedo bomber A torpedo bomber is a military aircraft designed primarily to attack ships with aerial torpedoes. Torpedo bombers came into existence just before the World War I, First World War almost as soon as aircraft were built that were capable of carryin ...

of the 1920s. It was developed by

Avro Avro (an initialism of the founder's name) was a British aircraft manufacturer. Its designs include the Avro 504, used as a trainer in the First World War, the Avro Lancaster, one of the pre-eminent bombers of the Second World War, and the d ...

to meet a requirement for a

heavy Heavy may refer to: Measures * Heavy, a characterization of objects with substantial weight * Heavy, a wake turbulence category used by pilots and air traffic controllers to refer to aircraft with a maximum takeoff mass of 136,000 kgs or mo ...

torpedo bomber for the

Royal Air Force The Royal Air Force (RAF) is the Air force, air and space force of the United Kingdom, British Overseas Territories and Crown Dependencies. It was formed towards the end of the World War I, First World War on 1 April 1918, on the merger of t ...

but was unsuccessful, only two prototypes being built.

Design and development

The British

Air Ministry The Air Ministry was a department of the Government of the United Kingdom with the responsibility of managing the affairs of the Royal Air Force and civil aviation that existed from 1918 to 1964. It was under the political authority of the ...

produced Specification 16/22 in 1922 for a long-range land-based torpedo bomber. The specification required that the aircraft be capable of carrying a 21 in (533 mm)

torpedo A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, such ...

or an equivalent weight of bombs and produced responses both from

Blackburn Aircraft Blackburn Aircraft Limited was a British aircraft manufacturer from 1914 to 1963 that concentrated mainly on naval and maritime aircraft. History Blackburn Aircraft was founded by Robert Blackburn (aviation pioneer), Robert Blackburn and Jessy ...

(the Cubaroo) and

Roy Chadwick Roy Chadwick, CBE, FRSA, FRAeS (30 April 1893 – 23 August 1947) was an English aircraft design engineer for the Avro Company. Born at Marsh Hall Farm, Farnworth, Widnes, the son of the mechanical engineer Charles Chadwick, he was the chief ...

, chief designer of Avro, initially produced a single-engined design, the Avro 556 powered by a

Napier Cub The Napier Cub was an unusual and very large experimental 16-cylinder 'X' pattern liquid-cooled aero engine built by the British engine company D. Napier & Son. The Cub was the only Napier 'X' engine design. First flown on 15 December 1922 ...

engine, similar to the Cubaroo. This was rejected in favour of a twin-engined aircraft using two Rolls-Royce Condor engines, the Avro Type 557 Ava and winning an order for two prototypes from the Air Ministry. Completed in secret (owing to its armament of a 21 in (533 mm) torpedo, thought to be able to sink the largest warships), the first prototype Ava (

serial number A serial number (SN) is a unique identifier used to ''uniquely'' identify an item, and is usually assigned incrementally or sequentially. Despite being called serial "numbers", they do not need to be strictly numerical and may contain letters ...

''N171'') flew in mid-1924. The Ava was a three-bay biplane of wooden construction, with the un-cowled engines between the wings. It had a biplane tail, initially fitted with triple

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, airship, or other vehicle that moves through a fluid medium (usually air or water). On an airplane, the rudder is used primarily to counter adverse yaw ...

s, of which the centre rudder was soon removed. The fuselage accommodated two pilots in an open cockpit, with nose and dorsal gun positions and a retractable ventral "dustbin" gun position that could be manned by the navigator/bomb aimer, who otherwise occupied a large enclosed cabin. The 2,000 lb (910 kg) torpedo or equivalent bomb load were carried on external racks under the fuselage. The Air Ministry dropped its plans to use the 21 in (533 mm) torpedo but Avro continued with construction of the second prototype, which was of all-metal construction but was otherwise similar to the first prototype, flying on 22 April 1927. While a modified version of the Ava was proposed to meet Specification B19/27 for a heavy bomber, it was unsuccessful, no further aircraft being built.

Variants

;Ava Mk I : First prototype. Wooden construction. ;Ava Mk II : Second prototype. Metal construction.

Specifications (Ava Mk I)

References

External links

Avro Ava
– British Aircraft Directory {{Avro aircraft 557 Ava 1920s British bomber aircraft Cancelled military aircraft projects of the United Kingdom Biplanes Twin piston-engined tractor aircraft Aircraft first flown in 1924

Design and development

Variants

Specifications (Ava Mk I)

See also

References

External links