Dunne D.1

John Dunne came to the Balloon Factory on June 1st, 1906, where he was appointed to the Royal Engineer Committee and placed in charge of the design, construction and testing of aero-planes. Teamed up with Colonel John Capper, Superintendent of His Majesty's Balloon Factory at South Farnborough in Hampshire, their first aircraft, the Dunne D.1, was ready in the spring of 1907. It was a single--seat glider with arrow-shaped biplane wings. Powered by two 12 h.p. Buchet engines, it was ready by the spring of 1907, and in July was removed in great secrecy to the Marquis of Tullibardine's Scottish estate at Blair Atholl, in Perthshire, for its first tests. It made one very brief unpowered flight, with Capper at the controls, during which its inherently stable properties were confirmed, but on its first attempt at a proper powered take-off, owing to faulty launching tactics it crashed, sustaining extensive damage. Back at Farnborough during the winter the D.1 was redesigned and rebuilt, with a new engine and a wheeled landing gear, to re-emerge as the D.4.

The D.1 proved the soundness of Dunne's ideas and was followed by further machines on the same principle; the D.3 was constructed at Farnborough and later ones built privately at Eastchurch. In addition, both seaplane and flying-boat versions of the Dunne biplane were built in America by the Burgess Company. But it gradually became apparent that inherent stability was not so essential for a military aircraft as good manoeuvrability.