Case of the German Fan Belt

Mar 11, 2000

RAY: It's 1936. Europe is on the brink of yet another war. In a secret location in Germany, German officers are gathered around the table with the designers of its new personnel carrier. They're going over every little detail, leaving no stone unturned. They want everything to be flawless.

One of the officers stands up and he says, "I have a question about the fan belt." He asks, "How long do you expect this belt to last?" The engineer replies, "Thirty to forty thousand kilometers, Colonel."

The officer says, "Not good enough! We need it to last sixty thousand kilometers." The engineer says, "It's merely a matter of taking the belt off and turning it over, because this is a flat belt. Not a V belt."

The Colonel replies, "That's unacceptable. Our soldiers will be engaged in battle. We can't ask them to be changing fan belts in the middle of the battle."

TOM: Well, he's got a point!

RAY: So, all the engineers huddle together, and they come up with a clever way to extend the life of the belt to 60 thousand kilometers. They do not change the material of the belt. In two minutes, they have a solution to the problem which satisfies the Colonel.


RAY: What they did was they manufactured the belt with a twist in it. Imagine if you took your own belt and joined the two ends together, so you'd have an inside of the belt and an outside. But imagine before joining them, if you gave one end a twist and made it into what's called a Mobius strip.

TOM: Of course! Now it's going to go on both sides all the time.

RAY: Exactly. And in essence, you've doubled the length of the belt. You have allowed it to run on the inside and the outside at the same time.

TOM: Does Detroit know about this? We don't have any Mobius strip fan belts on American cars.

RAY: Well, it's a little-known fact that the fan belt lobby is very strong in this country.

TOM: They don't want them to last twice as long.

RAY: Of course not! Nor do we, who replace belts. Anyway, who's our winner, Tommy?

TOM: The winner is Liz Walsh from Lexington, Massachusetts.

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