Montshire Minute: Frisbees

Originally aired during the week of September 2, 2001

Monday

Once upon a time there was a baker in Connecticut who made pies. Whether the pies were any good isn't really important for the purposes of this story, because he became world famous for something completely unrelated to pastry. The baker imprinted his name on the bottom of the lightweight tin plates in which his pies were sold. The pies became very popular, and around 1940 a group of Yale students in New Haven stumbled upon a new use for the discarded plates. They discovered that if spun into the air with the leading edge more or less parallel to the ground, the pie plates could travel remarkable distances. Soon competitions broke out to see who could fling the plate the farthest. The name of the baker? You probably guessed it by now. His name was Russell Frisbie, and he is known worldwide today not for his pies but for the use of his plates as the inspiration for a flying toy.

Tuesday

Just what is it that makes the Frisbee fly? There are lot of forces at work here, but perhaps it helps to think of the Frisbee as a flying wing. Hmmm. That doesn't really clear things up, does it? OK, how about this. Think of the Frisbee as a flying wing that maintains its stability through the air by the spinning motion the thrower puts on it. Is that any better? OK, when the Frisbee is flung - a little alliteration there - its leading edge is tilted slightly upward. The air passes more quickly over the top of the disk than the bottom. This creates a low-pressure area right above the Frisbee, which tends to tug the disk up. The difference in pressure above and below the disk creates lift-the anti-gravity force. Of course, everything that goes up will eventually come down, so sooner or later gravity wins out and the Frisbee drifts back to earth.

Wednesday

I'm telling ya', when it comes to Frisbees it's the spin control that counts. You can take the Bernoulli Principle. You can take aerodynamic lift. But without the proper spin, you got nothing. Go ahead. Give it a try. Throw a Frisbee end over and end, or upside down. What happens? It flutters to the ground like a wounded pigeon. See, everything that flies needs stabilizers. Birds have tails. Rockets have fins. Frisbees don't have tails or fins. But they do have spin, and that's what provides the stability for the flying Frisbee. You can see this at work on other objects as well - like tops, for instance. A top that's not spinning will fall on its side. When it spins, the top stays up on its tip. Sure you gotta have lift to throw a Frisbee. But you also gotta have spin, baby, and that's just the way it works.

Thursday

The design of the Frisbee has been refined over the years. But it still works on the same principle as the famous Frisbie pie tins flung around by college students decades ago. The Frisbee, like the pie tin, is round and lightweight, with sloped edges. From the side, the curved edge of the Frisbee resembles an airplane wing. As a plane moves forward, propelled by its engines, the air rushes more quickly over the top of the wing than the bottom. This creates a pocket of low pressure on top of the wing, which tends to pull it up. Also, as the wing pushes down on the air, the air pushes upward on the wing. Together, these forces lift the wing against gravity-and you get aerodynamic lift. The Frisbee works the same way, except it is not powered by engines. It is powered by you. Actually, it's all in the wrist.

Friday

In the late 1940s, a building inspector named Fred Morrison experimented with flying discs, and eventually created a molded plastic version he called the PlutoPlatter. In 1955 the Wham-O Company saw the commercial potential for this toy, and bought the rights. The company renamed the product after the Connecticut baker, Russell Frisbee, whose pie tins were famous across New England for their remarkable aerodynamics. Over the years several improvements have been made in the basic design to help aid the flight of the Frisbee. The little ridges on the top of the disk create air turbulence. This turbulence helps keep the Frisbee aloft a bit longer, in much the same way that small surface dimples increase the distance golf balls travel. The Frisbee has spawned several "spin-offs" (pardon the pun): Frisbee baseball and Frisbee golf, not to mention ultimate Frisbee.