The de Havilland DH.60 Moth is a 1920s British two-seat touring and training aircraft that was developed into a series of aircraft by the de Havilland Aircraft Company.
The DH.60 was developed from the larger DH.51 biplane. The first flight of the ADC Cirrus powered prototype DH.60 Moth (registration G-EBKT) was carried out by Geoffrey de Havilland at the works airfield at Stag Lane on 22 February 1925. The Moth was a two-seat biplane of wooden construction, it had a plywood covered fuselage and fabric covered surfaces, a standard tailplane with a single tailplane and fin. A useful feature of the design was its folding wings which allowed owners to hangar the aircraft in much smaller spaces. The then Secretary of State for Air Sir Samuel Hoare became interested in the aircraft and the Air Ministry subsidised five flying clubs and equipped them with Moths.
The prototype was modified with a horn-balanced rudder, as used on the production aircraft, and was entered into the 1925 King’s Cup Race flown by Alan Cobham. Deliveries commenced to flying schools in England. One of the early aircraft was fitted with an all-metal twin-float landing gear to become the first Moth seaplane. The original production Moths were later known as Cirrus I Moths.
Three aircraft were modified for the 1927 King’s Cup Race with internal modifications and a Cirrus II engine on a lowered engine mounting. The original designation of DH.60X (for experimental) was soon changed to Cirrus II Moth; the DH.60X designation was re-used in 1928 for the Cirrus III powered version with a split axle. The production run for the DH.60X Moth was short as it was replaced by later variants, but it was still available to special order.
Although the Cirrus engine was reliable, its manufacture was not. It depended on components salvaged from World War I–era 8-cylinder Renault engines and therefore its numbers were limited by the stockpiles of surplus Renaults. de Havilland therefore decided to replace the Cirrus with a new engine designed by Frank Halford built by his own factory. In 1928 when the new de Havilland Gipsy I engine was available a company DH.60 Moth G-EBQH was re-engined as the prototype of the DH.60G Gipsy Moth.
Next to the increase in power, the main advantage of this update was that the Gipsy was a completely new engine available in as great a number as the manufacture of Moths necessitated. The new Gipsy engines could simply be built in-house on a production-line side by side with the Moth airframes. This also enabled de Havilland to control the complete process of building a Moth airframe, engine and all, streamline productivity and in the end lower manufacturing costs. While the original DH.60 was offered for a relatively modest £650, by 1930 the price of a new Gipsy-powered Moth was still £650, this in spite of its state-of-the-art engine.
A metal-fuselage version of the Gipsy Moth was designated the DH.60M Moth and was originally developed for overseas customers, particularly Canada. The DH.60M was also licence-built in Australia, Canada, the United States and Norway. Also in 1931 a variant of the DH.60M was marketed for military training as the DH.60T Moth Trainer.
In 1931 with the upgrade of the Gipsy engine as the Gipsy II, de Havilland inverted the engine and re-designated it the Gipsy III. The engine was fitted into a Moth aircraft, which was re-designated the DH.60G-III Moth Major. This sub-type was intended for the military trainer market and some of the first aircraft were supplied to the Swedish Air Force.
The DH.60T Moth was re-engined with the Gipsy III and was initially re-designated the DH.60T Tiger Moth. The DH.60T Tiger Moth was further modified with swept back mainplanes and the cabane struts were moved forward to improve egress from the front cockpit in case of emergency. The changes were great enough that the aircraft was again re-designated, becoming the DH.82 Tiger Moth.
Apart from the engine, the new Gipsy Moth was still a standard DH.60. Except for changes to accommodate the engine the fuselage remained the same as before, the exhaust still ran alongside the left side of the cockpits and the logo on the right side still read ‘De Havilland Moth’. The fuel tank was still housed in the bulging airfoil that formed the centre section of the upper wing. The wings could still be folded alongside the fuselage and still had de Havilland’s patented differential ailerons on the bottom mainplanes and no ailerons on the top ones. Colour options still remained as simple as before: wings and tail in “Moth silver”, fuselage in the colour the buyer chose.
As there was no real comparison between the original DH.60 and the new DH.60G, the Gipsy Moth quickly became the mainstay of British flying clubs as the only real recreational aircraft in the UK. By 1929 it was estimated that of every 100 aeroplanes in Britain, 85 were Moths of one type or another, most of them Gipsy Moths. This was in spite of the fact that with de Havilland having switched from the Cirrus engine to its own Gipsy engine, surplus Cirruses were now pouring into the market and a trove of Cirrus-powered aircraft like the Avro Avian, the Klemm Swallow, and the Miles Hawk started fighting for the flying club and private market.
Although replaced in production by the DH.82 Tiger Moth, the Gipsy Moth remained the mainstay of the British flying scene up to the start of WWII. The war however marked the end of the Gipsy Moth and post-war it was quickly replaced by ex-RAF Tiger Moths pouring into the civilian market.