Kites

 Kites are a common type of flying device ignored by the technological advancements of today. A kite is a toy that has a light frame with a thin material covering it. A long string determines the flight path of the kite.The kite glides. But do you know how the kite works? 

  First, let us define a kite. A kite is a child’s toy that has a frame that is light and has very thin material which stretches over it and is flown in the wind and the kite is at the end of a long string. The structure of a kite is composed of three main components: the kite body, the bridle, and the control line. Fabric, plastic, or plastic are stretched over the framework, converting the framework into a wing. The modern day uses of the kite are for recreation, scientific research, and art(such as aerial photography).

  Let’s see a little about the kite’s history. It’s unknown about the origin and the exact date of the kite. However, the earliest use of the kite was 2,000 years ago. The first kite’s origin comes from a legend. A Chinese farmer tied a string to his hat to keep his hat from flying away. Later kites were used for military purposes. For example, the Chinese General Han Hsin of the Han Dynasty use of the kite was the first recorded use of the kite. He flew the kite over the walls of the city he was besieging to measure how far his army would have to tunnel to slip past the city’s defenses. Later, the use of the kite spread across Asia. The kite also contributed to the invention of the airplane(the plane the Wright Brothers invented). Did you know that kites were used during World War I? Also, during World War II, kites were used to signal stranded pilots. Homan Walsh flew a kite across the Niagara Gorge and and when his kite landed on the opposite side of the river and the bridge was built because Walsh’s kite’s string landed on the opposite side. 

Source: http://blog.nasm.si.edu/aviation/how-kites-fly/

 The kite is capable of flight due to several features. First, the kite’s framework is light as well as the framework’s covering(the paper/fabric/plastic part). Otherwise the kite’s weight would prevent itself from flying.  Lift also helps the kite fly. Lift is an upward force that pushes it in the air. Lift is created by the variations in air pressure. The kite’s weight forces the kite downward due to gravity. Thrust forces the kite in the direction of motion. Forward motion, moving air, and tension from string all create thrust. Drag is the opposite force of the direction of motion and is created from the difference of the back and front’s air pressure and the friction between the moving air and surface of the kite. The equation equals coefficient x ((density x  velocity squared)/2) x reference area.In order to launch a kite into flight, the force of lift must overcome the force of weight. But to ensure the kite is in steady flight, the forces must be in equilibrium(lift is same as weight and thrust is equivalent to drag).The kite’s tail helps the kite be stable in flight. If the kite reaches a high altitude where the winds are strong enough, then the person controlling the kite doesn’t need to run anymore to stay in the air. 

  The modern day uses of the kite are for recreation, scientific research, and art(such as aerial photography). One potential function of kites in the future include eco-friendly transportation. For example, one cargo commercial ship used a computer controlled kite to travel. In 2013, Makani tested a prototype of kite that would harness wind energy and send the energy to a ground station through the kite’s tether(the string). Wind turbines on the kite will generate the electricity. The kite’s tether is actually made up of a high strength core  surrounded by conductive wires. This kite will eliminate 90% of materials of the standard wind turbine. Also, the kite will generate 50% more energy. Japan launched a kite into space with a Venus probe. The kite’s name is Ikaros which stands for Interplanetary Kite-craft Accelerated by Radiation. The kite was developed by JAXA( Japan Aerospace Exploration Agency). The kite deployed its solar sail and became the first space mission to be propelled by sunlight. Engineers at JAXA hope that missions in the future will combine solar sailing with electricity to provide power to ion propulsion engines.

The possibilities of kites’ functions are endless.