Avro 500

The Avro Type E, Type 500, and Type 502 made up a family of early British military aircraft, regarded by Alliott Verdon Roe as his firm's first truly successful design. It was a forerunner of the Avro 504, one of the outstanding aircraft of the First World War.

Development
The Type E biplane was designed in parallel with the slightly earlier Avro Duigan, differing principally in being slightly larger and having a more powerful (60 hp) water-cooled E.N.V. engine. Both were two-bay tractor biplanes with unstaggered parallel-chord wings with rounded tips, a deep rectangular section fuselage bearing a rectangular steel-framed stabiliser, elevator and rudder with no fixed fin, and a tidy undercarriage with a pair of wheels on a transverse leaf-spring and a long central skid projecting forward of the propeller. This unremarkable description is of a remarkable aircraft. This aircraft layout dominated aircraft design for twenty years: the Avro 500 and the contemporary B.E.1 are among the first truly practical examples built.

The aircraft was first flown on 3 March 1912 by Wilfred Parke, and while top speed and rate of climb did not meet expectations, the aircraft excelled in every other way. However, its performance was not up to Roe's expectations, and a second example was built, modified to take the much lighter 50 hp (37kW) Gnome air-cooled radial engine. This first flew on 8 May 1912, and a height of 2,000 ft was reached in five minutes. The next day the aircraft was flown from Brooklands to Laffan's Plain, covering the 17 miles (28 km) in 20 minutes. The same day it demonstrated its ability to meet the requirements laid down by the War Office in the requirements for a "Military Aircraft" that had been published in connection with the forthcoming Military Aeroplane Competition, and the authorities were impressed enough to buy the aircraft and placed an order for two more examples of the aircraft, which Roe now renamed the Avro 500.

Service
The type proved an immediate success in service, and orders for another four machines plus five single-seat derivatives (designated the Type 502 by Avro) soon followed. Other examples produced included six for the British Admiralty's Air Department, one presented to the government of Portugal (paid for by public subscription), one kept by Avro as a company demonstrator, and one bought by a private individual, J. Laurence Hall, which was commandeered by the War Office at the outbreak of World War I). The first prototype was destroyed in a crash on 29 June 1913 that killed its student pilot. Avro 500s were flown by the British armed forces during the first years of the war, mostly as trainers. In service, most were fitted with ailerons and a revised rudder.

Operators

 * Royal Flying Corps
 * No. 3 Squadron RFC
 * No. 4 Squadron RFC
 * No. 5 Squadron RFC
 * Royal Naval Air Service
 * No. 5 Squadron RFC
 * Royal Naval Air Service