Into the Archives – Blackburn B20

The Blackburn B20 is one of the least known British aircraft designs of the Second World War. Although the project was abandoned in 1940 its existence was kept hidden until June 1945. What was so special about this aeroplane to warrant this level of secrecy?

Between the World Wars the design of flying boats had proceeded at a fantastic pace. By the mid 1930’s giant four engined flying boats such as the Shorts class and the Boeing Clipper were on the drawing board. The need to keep the propellers clear of the water meant that such designs had deep fuselages, far from streamlined. One way around this problem was to mount the wings and engines high above the fuselage on a pylon or struts, such as in the Consolidated Catalina and Dornier Wal designs, but such installations still produced drag. In 1936 Major J.D. Rennie, chief seaplane designer for the Blackburn Aircraft Company put forward a revolutionary design to meet Air Ministry Specification R1/36. His radical idea was to have the entire bottom of the flying boat hull able to be extended downwards for landing, and be retracted for flight, giving a slim streamlined fuselage and the promise of unprecedented speed for a flying boat.

Posted by HEP Communications | 06 August 2015

Photo credits: BAE System (Operations) Ltd.