skiff rig design

[vibes]

has anyone thought about having a 7/8 ratio skiff rig (namely Int 14). I am wondering if this concept would work. Right now we use 3/4 rigs generally.
If the topmast was still flexible it would depower, and perhaps offer a taller ratio jib, as well.
any thoughts

[sharpii2]

Originally Posted by vibes

has anyone thought about having a 7/8 ratio skiff rig (namely Int 14). I am wondering if this concept would work. Right now we use 3/4 rigs generally.
If the topmast was still flexible it would depower, and perhaps offer a taller ratio jib, as well.
any thoughts

The biggest advantage I can see with a 3/4 rig is that you can usually strike the jib and the boat will still ballance reasonably well. That has been my standard reefing technique throughout my years of sailing. It's simple, it's quick, and it is quickly undoable (I had one of my boats fitted with a jib down haul for just that purpose). The 3/4 rigged boats I have had had very stiff masts that were not intended to bend. On one of these boats, I could even drop the main and proceed under the jib alone, even up wind.

I never understood the principle of 7/8ths and the 9/10ths rigs that seem to be getting kind of standard now (maybe somebody here can enlighten me). Perhaps it's to get the CA to line up with the CLA better with these newer high aspect ratio bulbed keels.

Bob

This is an experimental rig that seems to work well though I don't have enough time on it to say for sure how well. Mechanically, the top of the jib uses a "gaff"(with adjustable upper 'outhaul') that is attached to the mast crane . The point of attachment on the gaff is adjustable and was about 33% aft in this picture. The way it works the whole rig develops twist as opposed to just both sails-similar to washout in an airplane wing. The amount of rig twist is fully adjustable.
aeroskiff_trial009.jpg
Address:http://www.monofoiler.com/images/aeroskiff_trial009.jpg

[gggGuest]

Originally Posted by vibes

has anyone thought about having a 7/8 ratio skiff rig

If you go too high on the jib then the gusts tend to power up rather than depower, which isn't great. This is even if the top mast is flexible. You name it, it has been tried...

[vibes]

If you go too high on the jib then the gusts tend to power up rather than depower, which isn't great. This is even if the top mast is flexible. You name it, it has been tried...



yea, i thought that,
just had a crazy idea..i think the jib luff would sag too much too.
I might stick to my original rig which is fast already

[mattotoole]

Originally Posted by Lorsail

This is an experimental rig that seems to work well though I don't have enough time on it to say for sure how well. Mechanically, the top of the jib uses a "gaff"(with adjustable upper 'outhaul') that is attached to the mast crane . The point of attachment on the gaff is adjustable and was about 33% aft in this picture. The way it works the whole rig develops twist as opposed to just both sails-similar to washout in an airplane wing. The amount of rig twist is fully adjustable.
aeroskiff_trial009.jpg
Address:http://www.monofoiler.com/images/aeroskiff_trial009.jpg

Assuming it would be allowed, it would be interesting to try your rig in a conventional open/restricted class, like I14 or NS14.

--

[gggGuest]

Originally Posted by vibes

I think the jib luff would sag too much too.

Least of your worries with modern rig tensions!

Matt, it would be an interesting experiment; I'm not sure how much of a negative the rather large backstay tension would be. I would like to experiment with two of these on identical boats till it was as right as we could get it then put a "normal" flex top "skiff " rig on one of the boats with equal area and see what happens.
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edit:--There are several aspects of this rig that are missing in the monofoiler pix:
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1) On the aeroSKIFF 14(see Peoples Foiler) the forward third of the main is carried right down to the deck. On this boat the same princible was to be tried: a "wrap" like the 49er but MUCH larger and composed of two pieces with the vang in the middle to achieve nearly the same effect as on the 14. In the rebuilding being done now I'm considering redoing the main and using the modified wishbone on the 14 instead of the wrap.
2) the head of the main on the monofoiler.com pix is held up by a standard diagonal batten because I ran out of time. It was supposed to have a " gaff" that also would allow adjustment of the camber in the head of the sail similar to the way I've done it on all my RC models. Needs some work to get that right and to determine whether that facillity should be adjustable underway or is it ok just to be able to set it for the days conditions. One requires more complication and a touch more weight but gives full adjustability of the head of the sail and the other would require dropping the sail to adjust.
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3) the upper endplates are not shown on the monofoiler .com pix and they are of questionable benefit anyway.
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4) the main on the prototype was designed to use camber inducers with a sock luff AND side stays but the camber inducers got postponed because they would have held up the first tests while being custom made(by me).