I'm an old monohull sailor. Prams, lasers, 470s, MORC, FORA, SORC etc. I've bought a NACRA F18 in Hong Kong. I know the mast roation controls are to de-power the main in connection with the down-haul. My questions are as follows:
1) What position to de-power the main?
2) what are the physics involved?
3) Does it help off the wind, down wind?
Thanks,
Chris

Take a look at this video of Mischa Heemskerk discussing the topic...basically, as a monohull guy, you know flatter sails for high winds and curved sails for light wind. He doesn't get in to the physics (thank goodness) but he does discuss sail shape and mast flex. I think he answers your other questions too...He also mentions that rotation can be overdone...ultimately, I think he's saying its all about how the boat feels.

Good luck...

http://www.youtube.com/watch?v=0V0wA1BbaFE

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Bert Scott
Niceville, FL
Nacra F18
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Are we talking about a 5.5 or F18, two very different boats?

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Ron
Nacra F18
Reservoir Sailing Assn.
Brandon, Mississippi
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valid point..However, the general concept is the same and the video did not go in to specifics the F18. But he does in the other videos in that series so that is a good disclaimer to make.

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Bert Scott
Niceville, FL
Nacra F18
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Thanks Beest,

Its actually an F18. Upwind one of the sweetest rides ever. Easy to control. Can power up or down easily. Off the wind like having a tiger by the tail. Trying to find the best way to control it. I don't think a whip and chair will work.

Chris

stop it, stop it....you're dangling ice water in front of a man who just crossed the desert.....I just bought an F18 and won't be able to sail it until Labor Day!! when I drive to pick it up...sounds fun, can't wait.

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Bert Scott
Niceville, FL
Nacra F18
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