1. Kites have
3 essential
characteristics:
• A structure designed to produce lift from the wind,
• A flying line (tether) that keeps the kite from flying
away,
• A bridle that aligns the face of the kite to the proper
angle in the wind for lift. In some cases, the flying
line attaches directly to the kite’s face or keel and
governs its angle of attack.
2. Four Forces of Flight
• Thrust: from the wind
• Lift: from the angle of the kite’s face into the wind
• Drag: from resistance or friction
• Gravity: from weight
How these forces interact to determine flight,
how your particular kite will fly on a particular
day, will be affected by all sorts of factors:
the size of your kite, its balance and bridling,
speed of the wind, its steadiness or turbulence,
the altitude at which you are flying, the flow of air through the material of your sail,
the size of your kite’s tail, the flexibility of your frame, the depth or shallowness of your
kite’s bow.
Extremely small differences in initial conditions may result in spectacularly diverging
effects.
13. Kites are heavier-than-air flying structures controlled by three main forces: lift,
gravity, and drag. Lift is the upward force created by wind pressure on the face of
the kite, which makes the kite rise and keeps it in the air. Gravity is the downward
force on the kite which works against lift. Drag is the air resistance acting on the
kite as it travels forward. The kite flies most efficiently when the three forces are
balanced at an imaginary point, known as the center of pressure.
http://www.grc.nasa.gov/WWW/k-12/airplane/kiteprog.html