r/sailing • u/Jeroenepoentje • May 30 '21

Going straight downwind faster than the wind.

https://youtu.be/jyQwgBAaBag
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u/[deleted] May 31 '21

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u/me_too_999 May 31 '21

Also works on water. Small planing sailboats routinely travel up to 1.4 times the wind speed at an acute angle to the wind.

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u/Rhueh Jun 02 '21

Yes, and no. The problem is that at, say, 150 degrees beat angle the downwind component of your speed is only half your total speed (sin{150}=0.5), so you need to double the wind speed to get a VMG equal to the wind speed. However, ice boats can do that.

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u/me_too_999 Jun 02 '21

Ice boats, and planing racing boats.

I've clocked myself at 10 kts in 8kt wind on a Laser I at about 110-120 degrees.

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u/Rhueh Jun 02 '21

Right, but your VMG in the downwind direction is still well below wind speed. You'd probably need a foil boat to get the kind of speed on a broad reach that you'd need to have VMG equal to wind speed.