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Old 24th October 2007, 07:00 PM   #17
Join Date: Sep 2006
Posts: 459

I`ve been doing a bit of research around forces and windstrength.
In 20 mph (a good sailing day perhaps a 6 or 7 metre) the perpendicular force on any thing in the breeze is around 10kg per square metre.We are handling forces of order (or upto a max ) 60 or 70kg.

At what I see as my limit (ie 40 mph) the loading has gone upto 38kg per metre. Assuming I handle a 3.5 max loading is in order of (or upto max ) 130kg.(plus forces on rest of equipment and me).

In a F10 (Around 60mph) the loading per square metre is now 83kg per metre and everything is happening 3 times as fast as first example.To keep forces similar to those used in 20mph you`d need under a 1 square metre !!! Even to feel like a 3.5 in 40 mph(which is pretty hairy to say least) you would still need under (well under) a 2 square metre. And you are now approaching roughly the surface area presented to wind by your body.Upwind would be impossible. (ie drag to lift ratio gets worse and worse as sail size approaches body size)

Think we should be bit careful about claims of what we can sail in.Somebody might try !

Take care.(Have a rest day when its F10)

(Figures from met office)

Good sailing.
Floyd is offline   Reply With Quote