Definition
A kite is a flying tethered aircraft that depends upon the tension of a tethering system. The necessary lift that makes the kite wing fly is generated when air (or in some cases water) flows over and under the kite's wing, producing low pressure above the wing and high pressure below it. This deflection also generates horizontal drag along the direction of the wind.
Basics
A kite is a flying object that is attached to the ground by a rope, or ropes. Kites can be flown for fun, or in competitions.
The kite was created in China, about 2,800 years ago. Later it spread into other Asian countries, like Japan and Korea. However, the kite only appeared in Europe by about the year 1600.
The first kites had sails made of paper or light fabrics such as silk. The poles were made from bamboo, or other strong but flexible woods, and the kite line was made from string or twine.
Modern kites are made from synthetic materials, such as ripstop nylon or more exotic fabrics on the sails. They have fiberglass or carbon fiber poles, and use dacron or dyneema for the kite lines.
Today, there are many different types of kite. Some are large and are made to look good, but some are smaller and are made for speed and competitions.
Topics of Interest
A kite is a flying tethered aircraft that depends upon the tension of a tethering system. The necessary lift that makes the kite wing fly is generated when air (or in some cases water) flows over and under the kite's wing, producing low pressure above the wing and high pressure below it. This deflection also generates horizontal drag along the direction of the wind. The resultant force vector from the lift and drag force components is opposed by the tension of the one or more lines or tethers. The anchor point of the kite line may be static or moving (e.g., the towing of a kite by a running person, boat, or vehicle).
Kites are usually heavier-than-air, but there is a second category of lighter-than-air kite called a kytoon which may be filled with hydrogen, hot air, methane, or helium; these stay aloft with or without wind; at calm they float; at wind they receive lift from buoyancy and aerodynamic lift. Kytoons were develop strongly by Domina Jalbert. Kytoons have been made in toy-scale as well as military large scale.
Kites may be flown for recreation, art or other practical uses. Sport kites can be flown in aerial ballet, sometimes as part of a competition. Power kites are multi-line steerable kites designed to generate large forces which can be used to power activities such as kite surfing, kite landboarding, kite buggying and a new trend snow kiting. Kites towed behind boats can lift passengers which has had useful military applications in the past.
History: Woodcut print of a kite from John Bate's 1635 book, The Mysteryes of Nature and Art in which the kite is titled How to make fire Drakes. The caption is from the its reprint in Joseph Strutt's 1801 book, The sports and pastimes of the people of England from the earliest period.Kites were used approximately 2,800 years ago in China, where materials ideal for kite building were readily available: silk fabric for sail material, fine, high-tensile-strength silk for flying line, and resilient bamboo for a strong, lightweight framework. Alternatively, the kite authors Clive Hart and Tal Streeter hold that leaf kites existed far before that time in what is now Indonesia, based on their interpretation of cave paintings on Muna Island off Sulawesi. The kite was said to be the invention of the famous 5th century BC Chinese philosophers Mozi and Lu Ban. By at least 549 AD paper kites were being flown, as it was recorded in that year a paper kite was used as a message for a rescue mission. Ancient and medieval Chinese sources list other uses of kites for measuring distances, testing the wind, lifting men, signaling, and communication for military operations. The earliest known Chinese kites were flat (not bowed) and often rectangular. Later, tailless kites incorporated a stabilizing bowline. Kites were decorated with mythological motifs and legendary figures; some were fitted with strings and whistles to make musical sounds while flying.
In 1750, Benjamin Franklin published a proposal for an experiment to prove that lightning is electricity by flying a kite in a storm that appeared capable of becoming a lightning storm. Benjamin Franklin wisely never performed his experiment, but on May 10, 1752, Thomas-François Dalibard of France conducted Franklin's experiment (using a 40-foot (12 m)-tall iron rod instead of a kite) and extracted electrical sparks from a cloud.
Military applications: Kites have been used for military uses in the past for signalling, for delivery of munitions, and for observation, by lifting an observer above the field of battle, and by using kite aerial photography.
Kites were the precursors to the traditional aircraft, and were instrumental in the development of early flying craft. Alexander Graham Bell experimented with very large man-lifting kites, as did the Wright brothers and Lawrence Hargrave. Kites had a historical role in lifting scientific instruments to measure atmospheric conditions for weather forecasting.
Kite festivals are a popular form of entertainment throughout the world. They include small local events, traditional festivals which have been held for hundreds of years and major international festivals which bring in kite flyers from overseas to display their unique art kites and demonstrate the latest technical kites.
A Bermuda kite is a kite made using traditional, geometric designs, quite colorful, and is an art form as much as a recreational tool. They are traditionally flown in Bermuda only at Easter. The kites are typically hexagonal, though larger examples, particularly, may be octagonal, or have even more sides. They are constructed from flat sticks arrayed like spokes of a wheel, with a nail at the axis. A string passes around the ends of the sticks, marking out the edges, and concentric strings are arranged inside of this, all contributing to the rigidity of the structure. Colored tissue paper is glued into the spaces created between strings and sticks. Using different colors, patterns are created. The kite has a single stick secured at one end to the axis, and rising at a shallow angle from the plane created by the other sticks. This stick, which forms the head of the kite, extends considerably beyond the perimeter of the hexagon. It passes over the mid-point of one side of the hexagon, and a string creates a triangular shape from the corner to one site of the head stick, to its tip, and back to the opposite corner. Strips of paper are folded and glued along this string. A long, cloth strip tail is fitted to the kite, without which it would be unable to fly.
Bowed kites such as the Japanese rokkaku, and traditional versions of the more familiar "diamond" shaped kites such as the Malay or Eddy, are tensioned into a bow in order to improve their stability to the point where a tail often becomes unnecessary.
A box kite is a high-performance kite, noted for developing relatively high lift. The typical design has four parallel struts. The box is made rigid with diagonal crossed struts. There are two sails, or ribbons, whose width is about a quarter of the length of the box. The ribbons wrap around the ends of the box, leaving the ends and middle of the kite open. In flight, one strut is the bottom, and the bridle is tied between the top and bottom of this strut. The dihedrals of the sails help stability.
Bow kites are leading edge inflatable kites that incorporate a bridle on the leading edge. They can be identified by a flat, swept-back profile and concave trailing edge allowing the kite greater depower. Bow kite design was pioneered by Bruno Legaignoux, and have been licensed to many kite manufacturers.
The Malay kite is a model of tailless kite. First introduced to the West in a New York newspaper article from October 1894, the Malay kite was used for recreation for centuries before this in parts of the Far East. The article detailed how a university professor ("Clayton") had erected a series of kites and bound them all together to one kite. These kites had no tail, were bowed and diamond shaped, and were referred to by the article writer as "Malay kites". However, the existence of a Malay-like design may have already been heard of in the United States sometime before the publishing of the article; in the last edition of the American Boy's Handy Book, another tailless kite is described (there referred to as a "Holland" kite). The description of this kite, which was to be included as a chapter in the book, was sent in to the author sometime around 1882, eleven years before the Malay kite was mentioned in the newspaper.
A tetrahedral kite is a multicelled rigid box kite composed of tetrahedrally shaped cells. The cells are usually arranged in such a way that the entire kite is also a regular tetrahedron. The kite can be described as a compound dihedral kite as well.
In geometry a kite, or deltoid, is a quadrilateral with two disjoint pairs of congruent adjacent sides, in contrast to a parallelogram, where the congruent sides are opposite. The geometric object is named for the wind-blown, flying kite (itself named for a bird), which in its simple form often has this shape.
A power kite or traction kite is a large kite designed to provide significant pull to the user. They come in three main forms: foils, leading edge inflatables and supported leading edge. There are also rigid-framed kites and soft single skin kites. There are several different control systems used with these kites which have two to five lines and a bar or handles.
Source: Wikipedia (All text is available under the terms of the GNU Free Documentation License and Creative Commons Attribution-ShareAlike License.)
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