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Old 06-07-2012, 08:24 AM   #1
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active fin stabilizers and assisting sails

Has anyone experience with using active fin stabilizers while simultaneously using assinting sails?

I had recentely fitted some Naiad stabilizers which work perfect and reduce roll to a great amount. Occasionaly, with wind from beam or aft we also use our stabilizing and assisting sails. When the Naiads try to reduce the angel of heel that creates a lot of drag slowing us down by 0.5 kts and reversing the positive effect on RPM and fuel consumption.
When taking out the "angel of heel control" from the Naiad steering console, they still work fine but with following seas they seam less effective. HAs anyone experience with that?

tx Wolf
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Old 06-07-2012, 10:48 AM   #2
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I have Niads as well

One of the features of stabilizers is to eliminate heal and roll.
so it is obvious that the natural heel induced by your stabilizing sail would cause the stabilizing fins to try and correct the heel. Fins are known to cause a reduction in speed of about a half knot. My fins run with a considerable amount of toe in which in it's self causes drag. I assumed that the toe in was set to aid in tracking similar to toe in on a car. We use toe in on twin rudders to keep the boat from hunting or over steering. When I raced catamarans it was one of the speed secrets we kept to our selves. One of the things stabilizers do is help tracking by countering a boats tendency to roll into a broach in following sea conditions. My guess is that your stuck with the drag induced by the stabilizers. Perhaps your boats keel is effective enough that you could eliminate any toe in your stabilizers my have and simply shut down the system in following sea conditions when using your sails. Since I don't utilize a steadying sail or assisting sail I haven't any experience with your set up. Just thought.
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Old 06-07-2012, 01:39 PM   #3
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tx for your contribution

you are right, in the basic configuration, the fins wil try to compensate the heel from the saisl which slows you down a lot

if you reduce the nput of the heel (by turning a knob), it then relys only on the acceleration signal; this still reduces rol; but in following seas you see (better feel) a difference: sails down and heel sensor active is more comfortable ...

by the way, I dont see much (any) difference in speed, perhaps the drag of the two lateral steel keels (that I had have removed to place the stabilizers) was even bigger that the drag of the turning fins
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Old 06-07-2012, 09:17 PM   #4
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Quote:
Originally Posted by Obelikx View Post
Has anyone experience with using active fin stabilizers while simultaneously using assinting sails?

I had recentely fitted some Naiad stabilizers which work perfect and reduce roll to a great amount. Occasionaly, with wind from beam or aft we also use our stabilizing and assisting sails. When the Naiads try to reduce the angel of heel that creates a lot of drag slowing us down by 0.5 kts and reversing the positive effect on RPM and fuel consumption.
When taking out the "angel of heel control" from the Naiad steering console, they still work fine but with following seas they seam less effective. HAs anyone experience with that?

tx Wolf
We have TRAC stabilizers, and they have a setting where the control unit accepts a degree of heel and corrects from that rather than from 0 degrees of heel. In other words, if you are heeled over from sail assist, or from poor trim that introduces 15 degrees of port heel, the system will accept 15 degrees of port heel as "vertical" and correct around that. Essentially that eliminates the problem you are talking about, and I wonder if Naiads don't have the same feature?
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Old 06-07-2012, 10:11 PM   #5
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My system doesn't

Quote:
Originally Posted by Delfin View Post
We have TRAC stabilizers, and they have a setting where the control unit accepts a degree of heel and corrects from that rather than from 0 degrees of heel. In other words, if you are heeled over from sail assist, or from poor trim that introduces 15 degrees of port heel, the system will accept 15 degrees of port heel as "vertical" and correct around that. Essentially that eliminates the problem you are talking about, and I wonder if Naiads don't have the same feature?
My system doesn't, but then I don't currently need it.
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