You and Your Students!
Vicki Cobb, Education World Science Editor
Discover how to fly a kite, and send up a flying saucer.
The weather is changing and it's windy. Want to get outside with your class and learn a little science? There's nothing more fun than flying a kite! If you've never flown a kite before, now is a good time to learn along with your kids. Even better, you may have an experienced kite-flyer among your students who can guide you and your class through the process.
Take your class outside on a bright, windy day. Fly as many kites as the kids bring in.
Prepare a "flying saucer" by making a small hole (a little bit bigger than the diameter of the kite string) in the exact center of a paper plate. Bring the prepared plate and the tape outside with you.
Get the kite aloft. (For this "test kite" you will need to fly it to the end of a limited amount of string, because) Once it has stabilized and is flying well, have a kid hold the string while you attach the saucer. Slide the plate onto the kite string with the bottom of the plate facing the ground. Tape the slit closed, but make sure the plate slides easily on the string. Push the plate up the taut kite string until the plate catches the wind. It will travel up the string till it hits the kite. Sometimes the plate stops rising if it blows against the string. But when the wind shifts, your flying saucer will continue climbing.
Kites are airfoils, objects that redirect the flow of air so that the air pressure under the kite is greater than the pressure on top of the kite. This creates a force called "lift" against the heavier-than-air kite, which rises into the air defying gravity. The lift on the kite is so great that the string must keep it from flying away.
The paper plate is a homemade "line traveler" or "kite ferry," as some people call them. They are as old as kite flying, which is an ancient sport. One of the best things about a paper-plate traveler is the puzzled look of passersby as they try to identify your very identifiable flying object. It is easier to believe in a flying saucer than a flying paper plate!
Over the years, kite fliers have invented some very clever variations of kite ferries. Sometimes they put a stop, such as a cork, partway up the string. One kind of traveler releases a parachute when it hits the stop. Another has a rigger mechanism that collapses a sail and sends the kite ferry back down the line.
Kite shops sell travelers in many different styles, including airplanes and butterflies. But it's more fun to invent your own. In fact, inventing kite ferries is just the kind of thing your kids might want to think about for an "Invention Day."
Article By Vicki Cobb
Copyright © 2006 Education World