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The Big Question

Ralph Lorenz, a scientist at Johns Hopkins Applied Physics Laboratory who works in planetary exploration, is author of Spinning Flight: Dynamics of Frisbees, Boomerangs, Samaras, and Skipping Stones (Springer, 2006).
Photo by Mike Ciesielski

Q: What's the Best Way to Throw a Frisbee?
A: "It's a tricky question, in the sense that I could maybe tell you from simulations and experiments that you should throw it with a spin rate of 8.7 revs per second and hold it at an angle of 3.8 degrees above the horizontal, or whatever. But it's a very different thing to actually execute those kinds of numbers because human motor control is not something we can program. So the short answer, in practical terms, is practice.

"I used to play Ultimate Frisbee, but I wasn't really thinking about it scientifically at the time. I got into instrumenting Frisbees from the perspective of instrumenting other things. I was making little instrument packages suspended by parachutes with a view to understanding how we might interpret such measurements on space probes, in particular the Huygens probe that went to Titan, Saturn's moon. Having built these little instruments, I had the idea, Oh, I could try doing that on a Frisbee. That'd be sort of fun. And indeed, it was fun. That got me into looking into the scientific literature, such as it was, being published on Frisbee dynamics, and I found that there's been very little work done on it. Then I branched out and looked at boomerangs and skipping stones, and I realized there's a unifying theme of spinning objects flying through the air — that interaction of gyrodynamics and aerodynamics that everyone knows about but is never really written down. It was just kind of neat." — Catherine Pierre

Return to June 2007 Table of Contents

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