De Havilland Moth

The de Havilland Moths were a series of light aircraft, sports planes and military trainers designed by Geoffrey de Havilland. In the late 1920s and 1930s they were the most common civil aircraft flying in Britain and during that time every light aircraft flying in the UK was commonly referred to as a 'Moth', regardless if it was de Havilland-built or not.

The DH. Moth series was one of the first practical light aircraft designs to be intended for civilian training and recreational use, rather than for military buyers. The Moth was also one of the first light aircraft to be mass-produced and was available to a much wider section of the general public than previous aircraft designs.

The first Moth was the DH.60: a straight-winged biplane two-seater. To enable storing the plane in small spaces, the DH.60's wings could fold backwards against the fuselage. "Like a moth" remarked Geoffrey de Havilland, an avid lepidopterist and so the plane was nicknamed Moth from the drawing board on.

The Moth aircraft were the first to feature differential ailerons, a design feature patented by De Havilland that greatly improved safety by reducing the risk of a spin. Previous aircraft ailerons had equal deflection- the control surface on one wing deflected by the same amount as the surface on the opposite wing for a given control movement, but in the opposite direction. Differential ailerons are rigged so that the aileron on the downside wing (the side towards the direction of turn) deflected less than the other. This reduced adverse yaw, reducing the chances of a spin. If a spin occurred, recovery was achieved by reducing lift on the non-stalled wing, rather than trying to increase lift on the stalled wing. Differential ailerons are still found on nearly all light aircraft today.

First variations of the name began with changes in the engine used for the DH.60: Variants with a Cirrus Hermes, Armstrong Siddeley Genet and de Havilland Gipsy engine became Hermes Moth, Genet Moth and Gipsy Moth respectingly. (The original ADC Cirrus powered DH.60 retroactively became the Cirrus Moth.) As the DH.60 became more and more popular, de Havilland decided to cash in on the fame of the original by giving each of his new designs a name ending with "Moth".

First of them was the DH.61: a giant 5-passenger biplane aptly called Giant Moth. Other "Moths" include the Leopard Moth and Hornet Moth cabin biplanes, the Puss Moth cabin monoplane and the Moth Minor low-wing two-seater. The most famous of the moths however, if nothing then for sheer numbers, is the DH.82 Tiger Moth: a biplane trainer used during World War II in Britain and the Commonwealth of Nations and the aircraft on which all World war II RAF pilots learned to fly.

A more detailed list of the various de Havilland aircraft using the name Moth is given below:

*Moth, Gipsy Moth and Moth Major (DH.60)
*Giant Moth (DH.61)
*Tiger Moth Racer (DH.71) (monoplane)
*Hawk Moth (DH.75)
*Puss Moth (DH.80A)
*Swallow Moth (DH.81)
*Tiger Moth (DH.82) (biplane)
*Fox Moth (DH.83)
*Leopard Moth (DH.85)
*Hornet Moth (DH.87)
*Moth Minor (DH.94)

The prototype of the DH.84 Dragon light passenger plane was originally called "Dragon Moth", but later the 'moth' in its name was dropped as the plane was a civil airliner and the name 'moth' was to be used for sportsplanes only.

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