imagination is the highest kite one can fly.. how kites fly

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Imagination is the highest kite one can fly.

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Page 1: Imagination is the highest kite one can fly.. HOW KITES FLY

Imagination is the highest kite one can fly.

Page 2: Imagination is the highest kite one can fly.. HOW KITES FLY

HOW KITES FLY

Page 3: Imagination is the highest kite one can fly.. HOW KITES FLY

From Wikipedia…

A kite is a flying tethered aircraft that depends upon the tension of a tethering system.

•Heavier than air•Has one or more surfaces to provide lift using the wind.•Must be tethered with a line.

Page 4: Imagination is the highest kite one can fly.. HOW KITES FLY

LIFT, DRAG, AND GRAVITY:

A kite and airplanes are objects that are flown by the lift created by air in motion over their wings.

An airplane relies on thrust from its engines. A kite is tethered in place and needs moving air (wind) to fly. A kite is effected by lift, drag and gravity.

Page 5: Imagination is the highest kite one can fly.. HOW KITES FLY

In other words, the wind pushes up on the kite. At the same time, wind passing over the top of the kite creates an area of low pressure along the back of the kite. This creates a pull from behind.

LIFTWind moving across the sail of a kite creates pressure. Lift results from this wind pressure.

Page 6: Imagination is the highest kite one can fly.. HOW KITES FLY

DRAG Drag is created by wind resistance on the kite's surface (and tail).

Drag can also result from turbulence behind the kite.

Page 7: Imagination is the highest kite one can fly.. HOW KITES FLY

GRAVITYGravity is the downward force created by the weight of the kite.

To fly, a kite needs to have enough lift to overcome gravity and drag.

Page 8: Imagination is the highest kite one can fly.. HOW KITES FLY

All of these forces - lift, drag, gravity, and the thrust of the wind come together in the kite at the center of pressure place called the tow point.

That's where the kite line (string) is attached to the kite.

Page 9: Imagination is the highest kite one can fly.. HOW KITES FLY

THE ANGLE OF ATTACK

By moving the place your string is attached to the kite on the bridle line, you can change the amount of lift that is created.

Page 10: Imagination is the highest kite one can fly.. HOW KITES FLY

The angle of attack is the angle that the kite leans into the wind.

Page 11: Imagination is the highest kite one can fly.. HOW KITES FLY

DIHEDRAL The one other thing that is important in understanding flight is something called dihedral .

This is a word from geometry that describes the angle formed when two wings (planes) come together.

Page 12: Imagination is the highest kite one can fly.. HOW KITES FLY

The dihedral angle of a kites wings helps the kite fly smoothly. If the wings lean back at the same angle, then the wind pushes equally on both wings.

If one side of the kite begins to turn further into the wind, then the wind will push harder on that side until the kite becomes stable again or crashes.

Page 13: Imagination is the highest kite one can fly.. HOW KITES FLY

So with a proper dihedral angle built into the kite's design, it will fly properly balanced in the sky.

That would be equilibrium

Page 14: Imagination is the highest kite one can fly.. HOW KITES FLY

If the kite is not properly balanced, it may not fly steady in the sky. To correct the problem:

•Try moving the tow point back•Check the kite for balance•Try adding tail (drag at the bottom of the kite

Page 15: Imagination is the highest kite one can fly.. HOW KITES FLY

Kites also need a steady wind to fly well. Wind Turbulence is what happens when the wind has to go around obstacles like trees, buildings or hills.The distance that it takes the wind to smooth out is seven times the height of the obstacle.

WIND TURBULENCE

Page 16: Imagination is the highest kite one can fly.. HOW KITES FLY

 1-3 mph  Smoke drifts lazily, branches are still, flags hang limp

 4-7 mph  Tree leaves rustle, flags move slowly

 8-12 mph  Flags fly, bushes shake, leaves move

 13-18 mph  Small branches shake, grass moves

 19-24 mph  Large branches sway, flags flap noisily

 25-31 mph  Trees shake, dust and sand flies

Natural Wind Speedometer Since you can't see the wind, how can you tell how fast it is

moving?You can see what it does to other things around you!

(8-12 mph is best for most kite flying)

Page 17: Imagination is the highest kite one can fly.. HOW KITES FLY

Imagination is the highest kite one can fly.