The Avro 508 was built at Avro’s Manchester works in December 1913 and assembled at Brooklands in January 1914.
First exhibited in Manchester in January 1914, the 508 was a wooden fabric-covered pusher biplane of unusual shape, resembling a back-to-front Avro 504.
Its top and bottom three-bay wings were equal in length, made of fabric-covered wood.
The Avro 511 was designed as a fast scout for military use at a time when the role of aircraft in war was first emerging.
It was a single-seat wood-and-canvas biplane.
The fuselage was of square cross-section and carried Avro’s characteristic “comma” rudder, with no fin.
The wings were heavily staggered and had pronounced sweepback, both features intended to improve stability.
They were not constructed with the usual span-length spars, but used a cellular approach.
The interplane struts were not the usual single-piece shaped rods, but built up multi-piece, wide chord structures covered in canvas.
There were conventional midsection “N” type struts between the fuselage and the upper wing.
Ailerons were carried on both upper and lower wings.
Most unusually for its time, the inboard lower wing featured landing flaps, so the 511 landed at a sedate 35 mph (56 km/h).
The single rotary Gnome Monosoupape was neatly cowled, though this was later modified to improve cooling.
Mainwheels were mounted on a single axle plus centre-skid undercarriage and there was a tailskid.
Later in 1914 the 511 was modified with a new pair of wings with no sweepback and a V-form (cranked axle), skidless main undercarriage, becoming the Avro 514.
The Avro 521 was a British two-seat fighter first flown in late 1915, based on the 504.
Only a prototype of the Avro 521 was built.
It was powered by a 110 hp (80 kW) Clerget engine, with provision for a .303 in (7.7 mm) Lewis Gun in the rear cockpit.
The Avro Pike was a large, three-bay biplane of conventional layout driven by two pusher propellers.
Three open cockpits were provided, the centre one for the pilot, with gunners fore and aft of him.
The Admiralty evaluated the type, but rejected it.
Avro then built a second prototype, substituting the original’s Sunbeam engines for Green E.6 engines instead and designated it the 523A.
The Avro 527 was an equivalent two-seat fighter reconnaissance derivative version of the 504 intended for the RFC with the much more powerful, 150 hp (110 kW) Sunbeam Nubian water-cooled engine.
It used standard 504K wings and a central skid, single-axle undercarriage.
Naval 504s had mostly been fitted with a vertical tail with a generous fixed fin, in contrast to RFC machines with the all-moving, comma-shaped rudder, and the 527 retained the fin as used by RNAS 504s.
The engine installation was very different from other 504s, with two tall, almost vertical exhaust pipes, one from each bank of the upright V-eight Nubian, discharging just above the upper wing.
Its radiator was mounted edge on (longitudinally) between the wings.
The 527 first flew sometime in 1916.
A version with wings of 6 ft (1.83 m) span was considered, the 527A, but there is no record of it flying.
The Avro 528 was an unsuccessful large span single-engined biplane built to an Admiralty contract in 1916.
It carried a crew of two, only one was built.
The Avro 529 was a twin-engined biplane long-range bomber of the First World War.
Two prototypes were built but no production ensued.
The Avro 530 was a British two-seat fighter biplane designed in 1916 to compete with the Bristol F.2A.
The plane itself was designed in 1916, but not flown until July 1917.
It was of fabric covered wooden construction, powered by a 200 hp (150 kW) Hispano-Suiza engine.
The Avro 531 Spider was a British fighter aircraft built during the First World War.
It did not proceed past the prototype stage.
The Avro 533 Manchester was a First World War-era twin-engine biplane photo-reconnaissance and bomber.
The Avro Type 557 Ava was a British twin-engined biplane torpedo bomber of the 1920s.
It was developed by Avro to meet a requirement for a heavy torpedo bomber for the Royal Air Force but was unsuccessful, only two prototypes being built.
The Avro 560 was designed for the 1923 light aircraft trials for single-seaters at Lympne Aerodrome.
The Avro 560 was an ultralight built of wood-and-fabric construction, a cantilever high-wing monoplane.
It was powered by a 698 cc Blackburne Tomtit engine.
The aircraft was flown by Bert Hinkler during the trials held in October 1923; the 560 did well and recorded an average of 63.3 mi (101.9 km) per Imp gal (4.5 L).
The aircraft was evaluated by the Air Ministry after the trials but was not chosen for further production and only one 560 was built.
The Avis was a single-bay unstaggered biplane with full-span ailerons on both upper and lower wings.
It had a fixed landing gear with a tailskid and could be powered by a nose-mounted 32 hp Bristol Cherub II engine or a 35 hp Blackburne Thrush radial piston engine.
It had tandem open cockpits.
First flown with the Thrush engine prior to the trials, it was refitted with the Cherub, and first flown with this engine by Bert Hinkler at Lympne on 30 September 1924.
On the next day it won the Grosvenor Cup at a speed of 65.87 mph.
For the 1926 trials it was re-engined with a 38 hp Blackburne Thrush, being eliminated after a forced landing.
In 1927, it was re-engined again with a Bristol Cherub I and passed into private ownership until it was scrapped in 1931.
The Avro 566 Avenger was a prototype British fighter of the 1920s, designed and built by Avro.
It was a single-seat, single-engine biplane of wood and fabric construction.
Although it was a streamlined and advanced design, it never entered production.
The Avro 571 Buffalo was a prototype British carrier-based torpedo bomber biplane, designed and built by Avro in the 1920s.
It was not selected for service, the Blackburn Ripon being ordered instead.
The Avro 604 Antelope was a British light bomber which was designed and built in the late 1920s to meet a requirement for a light bomber to equip the Royal Air Force, competing against the Hawker Hart and the Fairey Fox II.
It was unsuccessful, the Hart being preferred.
The Avro 706 Ashton was a British prototype jet airliner made by Avro during the 1950s.
Although it flew nearly a year after the de Havilland Comet, it represented an experimental program and was never intended for commercial use.
The Avro 707 is a British experimental aircraft built to test the tailless thick delta wing configuration chosen for the Avro 698 jet bomber, later named the Vulcan.
In particular, the low-speed characteristics of such aircraft were not well known at the time.
Aerodynamically, it was a one-third scale version of the Vulcan.
The Avro 720 was an in-development British single-seat interceptor of the 1950s.
It was designed and being developed by Avro in competition with the Saunders-Roe-built SR.53.
While at least one prototype was partially-constructed, the order for the Avro 720, and quickly thereafter the project entirely, was terminated prior to any aircraft having been completed.