Types of Kites
The simplest kind of kite is the two stick single-plane bow kite. It can be purchased ready made or it can be assembled from do-it-yourself kits or made completely by hand. For simple kites the sticks can be of any strong, light wood with a straight grain. The covering material can be ordinary brown wrapping paper, or a lightweight cloth, such as silk or nylon. Plastic sheeting of various kinds i s also used. In addition, cloth is used for the tail, and string for the flight line. More advanced types of the stick kite require three or four sticks. One of the best-flying versions of the two-stick kite is the Eddy, or Malay, kite.
Invented by W. A. Eddy, an Australian, the kite has a bowed crosspiece and requires no tail. It was widely used in World War II as a gunnery target.
The box kite consists basically of two rectangular boxes, open on two parallel sides each and connected by a common framework. It was invented in the 1890's by Lawrence Hargrave. Box kites are more difficult to build than stick kites, but they are excellent flyers and will maintain their position for long periods. Box kites also adjust well to changes in the wind, and they do not require a tail.
The fancier-shaped kites are not usually handmade except by expert kite builders. They can be bought already assembled in hobby and sporting stores. Fancy kites include Japanese fish kites, Chinese dragon kites, diamond-shaped Indian fighting kites, and nonrigid parachute kites. One of the most spectacular fancy kites is the Brazilian papagugo, or falcon, kite, which is shaped like a giant falcon and has a wingspread of about 8 feet. The sturdy fabric wings are hinged to the central framing shaft so that they adjust themselves in an up or a down position according to varying air currents and thus give a remarkably birdlike appearance in flight. In Brazilian contests, fishhooks are fastened to the kites' wing tips. Expert kite flyers maneuver the kites in long, swooping dives and prove their skill by skimming the ground so that the fishhooks pick up bits of paper and cloth placed there.
How a Kite Flies
Kites fly, like airplanes, on the aerodynamic principle of wind pressure against a heavier-than-air object. The motor and. propeller of the airplane create a wind pressure as they move the plane through the air. When the pressure is great enough to overcome gravity, the plane is pushed up and allowed to remain aloft. The same effect of wind pressure is created by the kite flyer as he runs across an open field . As the kite moves against the wind, the string tips the face of the kite forward. The wind pushes up on this tipped face and lifts the kite, just as a wedge pushed under an object lifts it up. As the wind continues to rush past the kite, the air below the surface of the kite is slightly compressed, and a partial vacuum is created above the kite. The increased pressure of the air below thereby raises the kite.
A strong wind is not required to fly kites. In fact, they fly best in a light, steady breeze of from 8 to 15 miles (13-24 km) per hour. With stronger winds it is difficult to keep a kite aloft. With flat kites that require a tail for balance, the stronger the wind, the more tail is required.
History of Kites
The art of kite flying was known to many ancient peoples. For example, archaeologists have discovered ancient Egyptian pictures showing kites being flown. The earliest travelers to Malaya reported that the natives flew large leaves and worshiped them as gods.
Kites have been used in a wide variety of scientific experiments. In 1749 two Scottish scientists, Alexander Wilson and Thomas Melville, attached a thermometer to a high-flying kite and were able to record the temperature high above the earth's surface. In 1752, Benjamin Franklin conducted history's most famous experiment with a kite. During a thunderstorm he attached a large brass key to the string of a kite. When the kite flew into a thundercloud, the key drew electric sparks. From that fact, Franklin was able to identify lightning as an electrical discharge. Although Franklin took several safety precautions, it was a very dangerous experiment, and he could have been killed by the lightning.
In the late 19th century, the U.S. Weather Bureau began using kites to record wind velocity and direction, barometric pressure, temperature, and humidity. They were used until the 1930's, when they were replaced by airplanes and balloons, which have greater reliability in all weather conditions.
Throughout history, kites have been used in military campaigns, most often as a signaling device. They were also used to hoist men aloft to observe the enemy's operations. In 1904, Alexander Graham Bell invented a giant tetrahedral, or four planed, kite in the shape of a pyramid. It was able to carry a man to a height of more than 175 feet (53 meters). The use of kites as a military device declined with the advent of the airplane. Their use as gunnery targets in World War II was an exception, however.
Kite Flying Safety Precautions
Kite flying is a rewarding hobby, and a safe one, provided that safety rules are followed.
No metal should be used in the construction of the kite because of the danger of attracting lightning. For the same reason, kites should not be flown during stormy weather or when the strings are wet. Kites should never be flown near electric power lines, telephone lines, or transmission towers.