When Watersports Become Dangerous | Science of Stupid: Ridiculous Fails

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·Nov 11, 2024

Some things just don't go together-- oil and water, gas and matches, tequila and fireworks. So you can imagine my concern when I heard about a combination of kayaking and surfing.

Then I saw this and thought perhaps I'm worrying about nothing. And then I saw this and realized I was right the first time.

All right. If we're going to go treating a kayak like a surfboard, we'd better prep on center of buoyancy and hydrodynamic drag. To remain stable, a kayaker keeps the center of mass directly over the kayak center of buoyancy, which is in the middle of its submerged volume. Traveling out to sea, it helps to keep the kayak perpendicular to the waves, because turning sideways can mean more hydrodynamic drag and a salty roll.

When catching a wave, you must ensure the nose doesn't dig into the water; otherwise, the resulting increase in hydrodynamic drag could produce a turning effect. Waves can travel hundreds of miles, relentlessly building speed and power before smashing into your kayak, but we should be OK-- providing we remember the rules.

Hold on a minute, should we be perpendicular to the wave or parallel to it? Yes, it was perpendicular. By hitting the wave almost parallel he presents a large surface area, which leads to enough hydrodynamic drag to flip the kayak.

We are out and ready to catch a wave. I'm videoing this just in case things don't go well. That's a little negative. Confident, confident. But well-founded. Good start, but here the nose digs in, slows down, and our friends enjoy the benefits of the turning effect.

Now these guys have got it nice and perpendicular, minimal drag. Like a knife through salty butter.

NARRATOR: Maybe it's safer to avoid all that nasty drag and head out of the surf to calm open sea. There it is. There it is.

NARRATOR: Oh, look-- a delightful little fish.

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