Devotti Single Hander

Originally posted by Mikey 14778 I vaguely recall a diagram that showed that the lift from an airfoil section is at 90 degrees to the 'flat' surface (stop me if I get too technical here). So if you put your boom on the centreline then, if the book is to be believed, the force will be at 90 deg to the direction you want to go and will all get soaked up by the CLR. But I'm not entirely convinced by this explanation. Anyone got a better one ?

But you're forgetting, in this example, that the sail is not a flat plane in line with the boom- it is, or should be, part of an aerofoil shape, with maximum curve (roughly, producing max power- but it's a lot more complicated than that in ways I don't even begin to pretend to understand) well forward and angledforward with respect to the plane of the boom.

i think the word you are looking for is CHORD (of the sail) rather than 'flat surface'

Originally posted by Daniel Holman Sten has it right on there - on a board the sails are inherently more twisted so up from the foot of the sail the chord line as you move up its height will be at some angle of attack -

Hmm not entirely true, most windsurf sails may fit that description but
old school Raceboard sails or even new Raceboard sails designed by
Raceboard Sail genii with super tight leeches built in Cuben Fibre don't fit
that descrpition.

But I get the power thing, it is a weight issue, big heavy old tubs would
need the power so don't sheet in too far nor over stuff it, heavy weights
penalty and of course they'll never know the lightweights joy of over
sheeting whilst looking down the clew on the rail five degrees higher and
a knot faster..

Edited by G.R.F.

first photo I found under "Raceboard Sail genii" nice board I want one

in most conditions its the fattys that can point higher because they can hold it down with lots of leach tension, if your heavy it needs to be windy before you can reach off because it won't plane with all that lard.

the best option for light people is the reach off  for speed and get the hieght back from increased lift off the foils.(in some conditions making you higher and faster)  if they try to pinch too much they havent got the weight to drive the boat and end up nodding.

for boards when you can't hold the rig down you just put a smaller one on and go faster with less drag.

Edited by sten

Cuben fibre finn sails are super light too around 1kg lighter for a finn sail, but didn't last very long, about 1 week so they didn't get very popular. it was a long time ago so the fabric may have improved? nice head tensioner how does it work? can you adjust it whilst sailing.