The Avro 511 was designed as a fast scouting aircraft just before the

First World War World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

. Modified, it became the Avro 514. Though it had innovative features, development did not continue after the start of hostilities.

Design and development

The Avro 511 was designed as a fast scout for military use at a time (1913) when the role of aircraft in war was first emerging. It was a single-seat wood-and-canvas

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 ...

. The fuselage was of square cross-section and carried Avro's characteristic "comma"

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally aircraft, air or watercraft, water). On an aircraft the rudder is used primarily to ...

, 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 strut In aeronautics, bracing comprises additional structural members which stiffen the functional airframe to give it rigidity and strength under load. Bracing may be applied both internally and externally, and may take the form of strut, which act in ...

s 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.

Aileron An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around ...

s were carried on both upper and lower wings. Most unusually for its time, the inboard lower wing featured landing

flap Flap may refer to: Arts, entertainment, and media * ''Flap'' (film), a 1970 American film * Flap, a boss character in the arcade game ''Gaiapolis'' * Flap, a minor character in the film '' Little Nemo: Adventures in Slumberland'' Biology and he ...

s, so the 511 landed at a sedate 35 mph (56 km/h). The single rotary

Gnome Monosoupape The ''Monosoupape'' ( French for single-valve), was a rotary engine design first introduced in 1913 by Gnome Engine Company (renamed Gnome et Rhône in 1915). It used a clever arrangement of internal transfer ports and a single pushrod-operated ...

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.

Operational history

The Avro 511 was on static display at the Olympia Aero Show in London in March 1914 and was entered for the

Aerial Derby The Aerial Derby was an air race in the United Kingdom sponsored by the '' Daily Mail'' in which the competitors flew a circuit around London. It was first held in 1912, with subsequent races in 1913 and 1914. Suspended during the First World Wa ...

Race around London in May. The race was postponed by bad weather. Though not as fast as had been estimated (95-100 mph/150–160 km/h), it was entered for the postponed race in June after modification into the Avro 514, but a mechanical failure while taxiing prevented participation. Repaired, the 514 flew successfully in July 1914, but no further development was undertaken.

Specifications

References

* {{Avro aircraft Biplanes Single-engined tractor aircraft 1910s British military reconnaissance aircraft 511 Aircraft first flown in 1913 Rotary-engined aircraft