Daggerboard - use of?

as for foil sweep this makes interesting reading... link

and here... link

So then we're all agreed now are we?

That when the bottom of the foil goes ahead of the top, in 'filled in' wind,
it acts in such a way that to continue efficiently it needs to be moved
aft..?

Yes?


So how do we now feel about planing skiffs with fixed foils when the nose
is lifted by the Spinnaker and or a wave and that action has the very same
effect?

Which is the point I was trying to make, and why skiffs in their present
incarnation are inefficient and will, like foiling moths, always have a
'speed ceiling' created by that inefficiency amongst others..(Like stern
drag or 'tail walking')

Interesting looking at things from a windsurfers perspective isn't it?

Edited by G.R.F.

Originally posted by redback You are right - ideally the board should sweep back and even better reduce in area but at high speed we'd not want all the turbulence caused by a centreboard case, so we'll have to stick to a dagger. I really must remember to get the board up a bit in a blow it might help reduce that horrible twitchy feeling when we're doing over 15knots.

But, in my limited experience, the 4k really lifts its nose when the kite powers up. The RS800 sails much flatter and you can sense it wanting to pitchpole you.

Looks like the Alto pole is quite high, lifting the bow?

Originally posted by G.R.F. So then we're all agreed now are we? Yes?

No. Its an over simplification which relates to certain specific circumstances, most especially an over flexible foil.

Originally posted by G.R.F. why skiffs in their present incarnation are inefficient

Oh good grief, here we go again... Skiffs are course racing boats. They're not intended to hit top speed on a limited number of directions only, so amazingly enough they're not as good at it as craft that are...

And the fastest course racing boat in the World are probably the solid wing sail C Class Cats, and according to the guys that sail them they struggle to get much past 20 knots... However they sail close to that *all the time* at amazing apparent wind angles... And in some repects, notably speed achieved as a multiples of wind strength, they are some of the most efficient water craft of all...

One of the dimmer witted statements you'll hear round the net is that boards aren't very efficient because whilst they can get damn close to 50knots, and will probably get there very soon (possibly beaten by the kiters), they can only do it is shedloads of wind. These folk claim that multihulls which can't handle the shedloads of wind but can do three times wind speed as opposed to not much more than one times are far more efficient than boards. Frankly that's ****, and I suspect you would agree.

Now extrapolate the logic...

Yeah but can you take your sandwiches on board?