Carl,
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<br>-A developemental class would allow a basic rating formula , I-thought the weight to sail area was best . -but --
<br>Not many I am discovering are really interested in this type of developement sailing -racing .
<br>More I am being told will be much more interested and understand one design iF TYPE of rules .
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<br>(Wouter) I expected as much, as a result of my F16 experiences. Now Sailarea to weight was a good starting point Carl, but your approach lacked simplicity and sophistications. Simplicity to be easily explained to others and Sophistication that would convince everyone that your approach would indeed produce equality between designs.
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<br>Honestly Carl, you even lost me on your weight/sailarea scale and I very much doubted if it would really produce equality. The fact that F16 HP produces equal performance ratios to F18 was due to a special Physical / mathematical coincidence that only worked when the F16 HP was around 100 kg's. A slighting scale which was still producing equality over a wider range like you proposed was alot more ambitious.
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<br>>>The interesting twist in devising a developement type rule that would fit N A 20s was to scale existing heavier older active 20 cat designs a larger proportional sail area insuring that they would be competitive , particularly in light air.
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<br>This approach is difficult to say the least and juist setting a overal sailarea limit was to crude to do this I'm afright. Area in the mainsail has a far bigger impact than the same area in a genaker. You did not take this into account. You also set all limits past the iF20 and most older designs were already having trouble achieving iF20 performance. However I still believe that N6.0, H20, P19 and Mystere can be made eqaul to the iF20 performance within a acceptable margin and against acceptable cost. With this in mind iF20 is the best compromise between old and new (US i-20's)
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<br>>>This would keep them active and already completely qualified to race in F-20 .
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<br>(wouter) Qualified ? yes, equal ? probably not.
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<br>>>Historically the problem with design developement rules is they create {rule beaters } -extreme designs with unfavorable sailing charicteristics . --
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<br>(Wouter) No the problem is mostly that the fear of such a thing happening is keeping sailors from joining and participating in these classes. Without participation you're dead. No make it a two step approach first create a class and then after several years you may adjust certain parameter WHEN sailors feel a need for it. That is the way the Tornado class did it.
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<br>-Wout ,-your comment was {unscientific } but if you examine the scale the Tornado 8.5 beam fits into the center using its basic existing sail area . {the T-is used as a benchmark in rating systems . } --The Inter 20 could be sailed as is , and add a larger 2nd chute , --The N 6/0 the same - some would need upgrades in sail area to be competitive at the top level .
<br>--The lightweight version was under existing iF 20S in sail area but 100 LB lighter .
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<br>(wouter) The last would be a monster to sail Carl. I mean same width more sailarea less righting moment. The US I-20 is already overpowered in anything more than a breeze. And the 20 ft. length would hold it back due to ineffect wetted surface to weight ratio. Optimation is not that simple.
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<br>>>-One thing to mention about Texel and ISAF is that they attempt to rate ALL cats , includind ones with slow features such as low aspect sails ,-skegs , no boards ,ect. where a racing class does not have to concern itself with this aspect , --In this class we have L and B defined , weight and sail area would be the variables , and other aspects are up to the designer and sailor .
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<br>(Wouter) Yes but under these L and B limits reducing weight and adding sailarea are in conflict with respect to controlabilty and therefor performance.
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<br>>>Wout if you have run through the Texel numbers at the low and high end of the scale you have pronounced [UNSCIENTIFIC } COULD YOU POST THE RATING NUMBER FOR THEM .,-low middle and top end .
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<br>(Wouter) No I haven't run through the calculators, you can do it yourself however. I made my remark based on other aspects.
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<br>>>Again they are a proposed scale that included all existing active racing 20 s in NA basically as they are . and would expect some refinement to be required before finalizing it .
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<br>(wouter) Including them by widening the rules does not make them equal.
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<br>Regards,
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<br>Wouter
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