If you’ve ever thrown a football or even watched a game on TV, you’ve probably noticed something: when the ball spins perfectly, it flies straight and far. But when it wobbles, it ends up very inaccurate. There’s a scientific reason why football coaches emphasize the “spiral.”

The Shape of the Football

A football is shaped like an oval, or more precisely, an ellipsoid. Because of that shape, the ball travels through air best when one of its pointed ends faces forward.

When the ball tumbles or spins the wrong way, air hits it unevenly. That extra air resistance slows it down and makes its path unpredictable. A good spiral keeps the ball’s tip pointed forward, slicing through the air cleanly.

Why the Football Spins

When you throw a spiral, you’re making the football spin quickly around its long axis (that cuts right through the length of the football). That spin gives the ball something called gyroscopic stability (the tendency of a rotating object to resist changes to its axis of rotation). The faster the ball travels, the more gyroscopic stability it has and the more likely it is to keep its spiral motion.

Why the Spin Matters

When a football isn’t spinning, it tumbles and wobbles as it travels. Each time it turns and changes its internal axis, a different part of it faces the air. Because the ball isn’t perfectly smooth or symmetrical in flight, the air doesn’t flow evenly around it. One side might get hit with more air than the other, and that uneven push from the air creates wobble.

Learn More

NFL Films Video for visual explanations – https://youtu.be/jFwDOMmXcEc?si=yGSv5p0LV8B-LcPq

Try it yourself – Go outside and experiment with different ways of throwing a football!