Avro 521

This is a special post as it's hasn't any drawing in it because we couldn't find any blueprint for this airplane.

The Avro 521 was flown on late 1915 was an hybrid that had some components of the original Avro 504. It was powered by a 110hp Clerget 9Z nine-cylinder rotary engine and could've been armed with a single 0.303 lewis machine gun mounted on the rear cockpit. It was tested in early 1916 by the Royal Flying Corps but the contract was cancelled and it seems that only the prototype was built which crashed at Upavon on 21st September 1916.

The Avro 521

Sources:
1. https://en.wikipedia.org/wiki/Avro_521
2. http://www.aviastar.org/air/england/avro-521.php
3. Salamander Books - The Complete Book of Fighters