Rudolph,
Did it sail bow down with the old rudders? Was there any noticable
change in trim with the front rudder raised? Did it make any
difference upwind or down? Do the new rudders steer ok downwind?
Sorry about all the questions, but the more I know, the more able I am
to sort it out.
Ben,
There is no question it is sailing bow down and no doubt this affects
the steering. The question is why is it bow down? I suspect it is
because the rudders are turned at a big angle. The only other change
is the keel. If it is the rudder angle, the next question is why are
they at such an angle? Obviously a clr/coe balance problem. But if
you lift the front one (or align it with the flow), the coe is ahead
of the clr of the aft rudder which should provide lee helm. The keel
will influence this, not sure how much. If you reduce the sail area
aft of the coe (reef the main, the lee helm should be even more
pronounced. Apparently (Rudolph?) it wasn't.
I have found that once any of the boats are moving, the helm is pretty
easy (see the various videos). BD is the exception to this. The
time when it can be tricky to steer is coming out of a shunt. That is
when big rudders and no fixed foils work best, in my experience.
All very perplexing.
rob
On Tue, Mar 8, 2011 at 6:03 PM, Rudolf vd Brug <rpvdb@freeler.nl> wrote:
> Hi,
>
>>Forgetting the draft requirement, do you thhink they would have worked
>>better if they were the same size, or even slightly larger than the
>>originals?
>
> Comparing the two systems the old rudders being wider apart was clearly
> better.
> The area of the old rudders seemed generous. We sailed with rudders
> partially raised which didn't change the feel much if any.
> Front rudder up or down, no difference.
> That is why I think extra area on the new ones wouldn't make much
> difference. If it's not working with a bit less area it's not
> good enough. That may be the present situation (less area that is).
>
> Maybe the effect of the keel is simply that it keeps CLA closer to the
> centre than without one in bow down trim.
>
> Rudolf
>
>
>
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