Thread: Discussion IOM General Discussion
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Old Dec 11, 2009, 03:03 AM
Robert May is offline
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Originally Posted by hew565 View Post
Are you saying that with a separate trim on the jib, that the nose of an IOM will not submarine in a breeze? Or that I will not need a rudder that will "boil the water"?

I do like some weather helm on my boats and feel it is faster than no-helm upwind. You will not be able to detect a lift if the boat does not want to naturally head up into it.

Are there any "real" boats that are sailing with a "laminar flow" hull that you describe? Since all "real" boats have a separate jib and main trim, why do they need rudders?

With a twice around upwind/downwind course taking about 12 minutes to complete, how much time will you lose trimming your jib instead of hitting the shifts? Will you be able to manouver with another 20 boats at the starting line with a "variable camber" rudder?
Hull design will stop the submarining, separate jib control will reduce boiling.

If you understand exponential throws it is possible to have a rudder that is variable camber around its centre but which becomes traditionally active beyond 25% throw. The variable camber will reduce induced drag when traditionally active. Yes you do need a rudder for aggressive start line positioning but until 10 seconds before the start you need placement control rather than ultimate boat speed.

If we were sailing identical boats yours trimmed for weather helm and mine not you would do trim out your weather helm in an instance. If you are at the front of the fleet sailing with weather helm then I am happy to say I am wrong and adopt the same technique. As soon as I have learnt what you are doing better than me I will go back to beating you.

After the start a rudder is along for the ride or for the aggressive change of direction. Given a choice would you rather give yourself clear air and boat speed and sail confidently across the fleet on Port or are you happy to tack into their lee and follow them for another runner up placing.

With the ability to adust the jib independantly you will not lose a single split second in your 12 minute race it is an automatic function . If you have flown manually coupled aileron an rudder on fixed wing or have "flown" the tail rotor on a helicopter you will know that very quickly it is possible to split think your fingers and thumbs on your individual hands.

I am not here to throw sticks in the IOM pond, it was pointed out that the rules are International and therefore won't get changed. RCGroups is also International and it only takes one person on one of those governing bodies to read this thread that it is possible to consider a small change to the rules to improve the class and change becomes a possibility.
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