Wind speed - sail size

the formula I use is sail size(in sq.meters)= 10-(0.3 x wind speed), with wwind sspeed in mph. I am 150 lbs and round the formula up to the next higher sail size. Generally works below about 20 mph. I know its not scientifically correct as force on a sail is not linear in relation to wind speed.

So that's sail size = 10 minus (.3 x 15mph) sail size = 10 x 5 sail size = 50?

Hi,

I am not a firm believer of changing sail size according to wind speed it makes for a really funny sights on the beach where you see guys spending 20 minutes with assortied electronic gadgets trying to decide size based on the, usually variable, readings they get.

On top of it, sail size is not just a function of wind speed but also of current and wave size (e.g at my weight a 6.5 is enough for around 15miles/hour wind with no swell, but it is not so if there is a relatively large swell, say 3 feet, for example at the end of a day when the wind is going down. Similarly if there is current in the same direction of the wind the sail would not be enough).

I think you should learn to judge conditions and have a quiver of sails to match.

At 150 pounds in the Bay area I use a 4.8, 5.5, 6.5, 8.0 and I can probably get away with a 5.0, 6.0 and 8.0 (but some more overlap is nice to have). You can probably use a 8.5, 7.0, 6.0, starting with a 7.0 ...

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