Aircraft fabric covering often used in the restoration of older types that were originally covered using traditional methods. The purposes of the fabric covering of an aircraft are: Pioneering aviators such as George Cayley and Otto Lilienthal used cotton-covered flying surfaces for their manned glider designs. The Wright brothers also used cotton to cover their Wright Flyer. Other early aircraft used a variety of fabrics, silk and linen being commonly used. Some early aircraft, such as A.V. Roe's first machines, even used paper as a covering material. Until the development of cellulose based dope in 1911 a variety of methods of finishing the
Types of motorcycles used for motor-paced cycling events. While motorcycles typically have two wheels, some motorized tricycles are classed as three-wheeled motorcycles. Some brands have made various types of three-wheelers direct from the factory. Most of these vehicles are treated as motorcycles for registration or licensing purposes. Tilting three-wheelers keep all three wheels on the ground when they lean to negotiate curves. These include Honda's Gyro range, all of which have a front wheel that leans and a pair of rear wheels that do not, and the Piaggio MP3, which has two front wheels and a single rear wheel, all of which lean.