How Do Frisbees Fly?
When a Frisbee soars through the air, its spinning motion is what keeps it flying. Operating on the principle of an airfoil — any flying object designed to reach maximum “lift” — the light, saucer-shaped Frisbee’s spinning fights the pull of gravity.
This is what keeps the Frisbee in the air. When it has used up all the power that you put into your toss, the Frisbee softly sets down on the ground.
As air passes over the curved upper surface of the Frisbee it speeds up, creating a low pressure region on top of the Frisbee. Below the Frisbee, air passes more slowly, creating a high pressure region.
The difference in pressure gives the Frisbee lift. The shape of the Frisbee generates lift, but it needs more than that for flight.
Try throwing a Frisbee without spinning it. Notice how it wobbles and tumbles. The shape of the Frisbee may be generating lift, but the Frisbee is unstable. It cannot stay upright and eventually stalls (falls).
All flying things must have something that makes them stable during flight; airplanes and birds have tails, rockets have fins. For a Frisbee, it is the spinning motion generated from the Frisbee throw that stabilizes the Frisbee as it flies.