May 5, 2012: The de Havilland Tiger Moth
History of the Tiger Moth
The original light aircraft that de Havilland developed, the DH60 Moth, was so successful that production was increased from the initial rate of less than one per week to more than three per day. Several different versions were eventually produced along with a number of different engine options. One such version was the metal-framed DH60M ‘metal moth.’ This was submitted to the Royal Air Force as a potential primary trainer. Although the Ministry liked the aircraft, they felt that the positioning of the upper wing and fuel tank directly above the front cockpit was not ideal for an instructor wearing a full flying kit and parachute.
De Havilland began work on modifying the airframe of a DH60M. To clear the front cockpit the wings had to be moved forward some 22 inches. This threw the aircraft’s balance out, the centre of gravity now being behind the centre of lift. To remedy this, the wings were swept back by 19 inches, which then created another problem. Taxiing, or a bumpy landing, could cause the lower wingtips to hit the ground. This was cured by slightly increasing the dihedral of the lower wings. To further assist getting in and out of the cockpit, the hinged door panels were deepened. A 120 hp Gipsy III inverted engine was fitted to improve the view over the nose, removing the four upright cylinders of the Gipsy I from the pilot’s line of sight.