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Why Planes Fly…or Don’t!

There are lots of ways that things can fly They can be lighter than air, like a party balloon, and float on the breeze. They can be picked up by the wind, like a kite, or a spider, or a dandelion seed. They can rise on a jet of hot air or gas, like a rocket. They can flap their wings, like hummingbird sand bees. They can be pushed or pulled by an engine, like a jumbo jet. Or they can glide on wide-spread wings, like sailplanes, eagles, and paper airplanes.

But what do we mean when we talk about flying?

To be flying, an object has to stay in the air and not fall down. Some people might tell you that the best paper airplane, the one that goes farthest of all, is a tight wad of paper. But that isn’t flying. The wad is falling from the moment it leaves your hand. To be flying, it has to keep going steadily, and not slowdown or dive to the ground. Paper airplanes can’t stay up forever, but they can glide a long way, down a long straight line, before hitting the ground.

This section will tell you how those wings of paper really fly.