What is a kite? • Kite – is a heavier than air craft that depends on the wind to overcome gravity to fly
Historical Kite Events • 1827 – George Pocock used kites to pull a horseless carriage. • 1907 – Dr. Alexander Graham Bell lifted his wife off the ground using a kite made of over 3,000 tetrahedral cells. • 1989 – Kite flying becomes a sport with the establishment of a national stunt kite circuit.
Parts Of a Kite • Bridle – Keeps the kite at the proper angle to the wind and often supports the kite at multiple points. • Fittings – These includes stick to stick fittings and stick to fabric fittings such as : glue, tape, or pockets. • Keel – Similar to a bridle, acts like a rudder. • Line – Prevents the kite from flying away, thicker line is stronger and the strength is measured in pounds.
Parts Of a Kite .. (continued) • Sail – Directs the air to give lift • Spars – Gives a kite structure, some have special names like “spine” and “spreader”. • Tail – Adds drag to keep the kite pointed into the wind • Tow point – Connection point from the line to the bridle.
Kite Styles • Flat • Snake, Hexagonal, • Diamond, Delta • Bowed Eddy, Edo, Rokkaku • Cellular Star, Box KiteMulti-line Dual-line Stunt Kite, • Quad-line Stunt Kite • Fighters & • Flexible • Hata, Indian Fighter • Figure Bird, Bat • Soft Soft Airfoil, Parafoil, • Flowform • Stacks and • Trains • Single-line train of Kites, • Dual-line stack of kites
Newton’s First law • An object will stay at rest until a force acts on it then the object will move. This is normally taken as the definition of inertia. The key point here is that if there is no net force resulting from unbalanced forces acting on an object (if all the external forces cancel each other out), then the object will maintain a constant velocity. If that velocity is zero, then the object remains at rest.
Physics of Kites • How does a kite become stable? To provide stable flight, the kite must have some aerodynamic shape that can equalize opposing forces : Lift vs. gravity, Roll/pitch/yaw, and lift + drag vs. line tension.
Pitch is up and down like a box lid. • Yaw is left and right like a door on hinges • Roll is rotation.
Definitions • Thrust – To push or drive quickly and forcibly. • Lift – To direct or carry from a lower to a higher position. • Gravity is the force that pulls things to the ground. • Tension – the act or processing of stretching something tight.
Website Resources • http://www.pcmag.com/encyclopedia_term/0,2542,t=pitch-yaw-roll&i=49313,00.asp