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Glider

The glider is a kind of fixed wing aircraft, which is supported by the dynamic reaction of air on its lifting surface in flight, and its free flight does not depend on the engine. Most gliders do not have engines, although motor taxis have small engines that can extend flight time by maintaining altitude (normally, the aircraft is on a continuous descent slope) when needed, some of which are powerful enough to take off.

The structure of the wing, aerodynamic efficiency, pilot's position, controls, and type of intended use vary. Most use meteorological phenomena to maintain or increase height. Gliders are mainly used for gliding, hang gliding and Paragliding in the air. However, some spacecraft are designed to descend as gliders, and in the past, military gliders have been used in combat. Some simple and familiar types of gliders are toys, such as paper airplanes and light wooden gliders.

In most cases, it is difficult to verify the early pre modern flight, and it is not clear whether each aircraft is a glider, kite or parachute, and to what extent they are truly controllable. Generally, the incident was recorded only a long time after its alleged occurrence. A 17th century report reported an attempt by the 9th century poet Abbas Ibn firnas to fly near Cordoba, Spain, resulting in serious back injuries. Wilmes of Malmesbury, the monk of Malmesbury (C. 1080 – 1143), is a monk and historian who reportedly flew out of the top floor of the abbey in Malmesbury, England, about 200 meters (220 yards) down and injured his legs between 1000 and 1010 A.D. According to the reports, they all used a set of wings and blamed the crash on the lack of a tail. It is said that Hez â rfenahmed Ç elebi glided a glider with eagle wings on the Bosphorus Straits from Galata tower to Istanbul's Bansk ü Dar District in 1630-32.

During the two world wars, under the chairmanship of RH ö n-rossitten, leisure taxiing prevailed in Germany. In the United States, the Schweizer brothers in Elmira, New York, have produced sport gliders to meet new needs. Glider continued to develop in 1930's, glider movement has become the main application of glider. With the improvement of the performance of gliders, gliders have been used for cross-country flight. If the weather is right, now they can regularly glide hundreds or even thousands of kilometers every day.

During the Second World War, many countries developed gliders for the army. Towards the end of the war in 1944, the POWs even secretly built a glider, Colditz cock, as a potential escape method in the orag iv-c.

Gliders were developed for recreational purposes in the 1920s. As the pilot began to understand how to use the rising air, the lift drag ratio of the glider was very high. These allow longer taxis to reach the next "lift" source, thus increasing their chances of long-distance flight. Although the term can also be used to refer to a descent flight, it has caused a popular movement known as gliding. This kind of glider designed for takeoff is sometimes called a glider.

Gliders are mainly made of wood and metal, but most of them now use composite materials made of glass, carbon fiber and aramid fiber. In order to minimize the drag, these types of aircraft have long and narrow fuselages, that is, the aspect ratio. At first, the appearance of the early hydrofoil aircraft was very different. With the development of technology and materials, people are eager to achieve a perfect balance between lift / drag, climb ratio and sliding speed, which makes engineers from different manufacturers create similar designs around the world. Single seat and two seat gliders are available.

At first, the training is completed by a short "jump" to the primary glider, which is a very basic aircraft, without cockpit and few instruments. Since the Second World War, we have been training on two dual control gliders, but the high-performance two seat gliders are also used to share the workload and enjoy the fun of long-distance flight. Originally, sleds were used to land, but now most of them are on wheels, usually retractable. Some gliders (called mobile gliders) are designed for unpowered flight, but can deploy pistons, spinning, jet or electric engines. Fai divides the gliding competition into gliding competition categories mainly based on span and flap.

Fai defines a class of super light gliders based on the maximum weight, including some called microgliders and some called "armchairs". They are light in weight, easy to transport and fly in some countries without permission. The performance of the super light glider is similar to that of the hang glider, but because the pilot can be tied to the upright seat in the deformable structure, it has higher crash safety. They usually land on one or two wheels, which distinguishes them from hang gliders. Several commercial super light gliders have come and gone, but most of the current development is done by personal designers and home builders.