Gybing Plates

So I think I've got it now, amazing learning something new when you think you know everything..
Although tbh the term as y'all use it never really came up much in our world, only the Original Windsurfer acted perceptibly as described and forced a crabbing technique to force the boat to weather to overcome 'leeway', hell, I still can't believe I've not used the term before, maybe its early onset altzeimers.

Anyway in essence the trick then must be to align the angle of the plate offset, to the percieved leeway angle of a given craft. It then follows that this angle should be adjustable, because that leeway angle must surely alter with wind strength on some hull forms, in fact logic then suggests the actual internals of the cb case should be constructed to vary that angle, has that been done I wonder..

My there's lots to think about, but thanks everyone for the input, it's been fascinating and thought provoking.

Edited by iGRF - 28 Jan 16 at 10:27am

Originally posted by iGRF maybe its early onset altzeimers

You could 'spring' the diamond, so more pressure gives max angle and less pressure reduces it, but I'm not sure that's the way round you want it, then actually you could spring the other side for the opposite effect, wait a minute, this needs more dwelling on, so like a suspension ATB you springload with adjustable tension, I'm going to think further about this...

Originally posted by JimC Originally posted by iGRF It then follows that this angle should be adjustable, because that leeway angle must surely alter with wind strength on some hull forms, I've not heard of it being done, but I agree, that would seem to be the logical approach. Indeed in an ideal world I suspect one would dial in a lot of angle coming out of a tack, and reduce it as the boat comes up to speed and the foil generates more lift. The ultimate expression would presumably be a daggerboard in which the leading portion was a gybing foil with adjustable angle of incidence, and the trailing portion was a flap so the foil was adjustable with the total camber able to be altered... I think I know a Canoe sailor in California who would build that, if indeed he hasn't already!

You can adjust the AoA of a gybing dagger. Done plenty on i14s and on Chris Maas breathtaking ICs. Bear in mind you can be doing say anything from 7kts to 12kts upwind in an i14 while twin stringing, so remembering Cl varies with V^2 thats a big Cl range and hence Alpha range.

Originally posted by iGRF You could 'spring' the diamond, so more pressure gives max angle and less pressure reduces it, but I'm not sure that's the way round you want it, then actually you could spring the other side for the opposite effect, wait a minute, this needs more dwelling on, so like a suspension ATB you springload with adjustable tension, I'm going to think further about this...