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by coffeenut 5701 days ago
The key point that's missing in this headline is that it attains that speed 'directly downwind'. Going crosswind is easy to attain speeds like this. The confounding 'magic' is that it can do this directly downwind.

As a mind experiment to explain why this seems impossible, think about what happens when the vehicle gets up to exactly the speed of the wind. At that point, there's no net wind pressure on the vehicle (if you were on the vehicle, there would be no apparent wind on your back or on your front), yet the vehicle still continues to accelerate!
2 comments
est 5701 days ago
> The key point that's missing in this headline is that it attains that speed 'directly downwind'... As a mind experiment to explain why this seems impossible,

After reading TFA and watching this video[1], I think you are wrong.

[1]: http://www.youtube.com/watch?v=xHsXcHoJu-A

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ck2 5701 days ago
Okay, I changed "wind" at the end to "downwind" to imply your point.

I wonder if this technology could be used on cargo ships to reduce fuel use.

Some of them use sails now but this seems better.

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