Bought curved boards for a Nacra 16 just because looks like fun.

Also purchased after some reading everyone should have them with curved boards!

https://nacrasailing.com/…nacra-15-f16-mkii-single.

Any advise on installing? at what height from the bottom of the rudders? Angle or how they should line up with the boat?

Thanks,

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Steve
Nacra Inter 20
Okemos Michigan
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I've seen these mounted from 1/3rd to 1/2 way up the rudder...in general we've found it faster to have a full T-rudder (foiling setup) completely immersed, even in light air. This improves the rudder efficiency and reduces waveform drag from the winglet piercing the waters surface, plus it tends to jerk the steering around less. So m suggestion is to mount them as low on the rudder blade as is practical structurally. I would check with Nacra on that, their latest blades (at least on the Evolution) are quite long and a smidge fragile at the bottom.

Angle: I recall Nacra publishing a guide. Regardless, parallel with the waterline is ideal, which is basically perpendicular to the transom.

I do agree that C-boardsfoil rudders are a pretty sweet setup...a little bit more drag than straight boards/rudders in very light conditions, but in 10ks+ they really let the boat come alive. A big plus is you can push the boat super hard; I'm sure its possible, but pitchpoling a boat with C's/T's is a mighty tough feat...