Geert,
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<br>>>Can you send me an example how you calculate the allowed jibsize?
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<br>Yes, I will use something like the Texel calculator that is already available on my personal webpage www.geocities.com/kustzeilen/
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<br>This is example however because I'm still looking at the ISAF system and working on some independed calculation methodes (like wetted surface area) to validate the use of a rating system like ISAF (Texel)
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<br>The form, and I think that you were asking that, will be something like the Texel system were one parameter is left unregulated so that final speed potential can be equalized by changing this parameter. In practice, fill in all measurements in the calculator and start changing jibsize (jib luff) till the final rating equals 103,0 uder texel or 1,009 under ISAF.
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<br>>>I assume you take the complete set of formula’s from Texel or Isaf, change the value for “rated weight” for boat weight+real crew weight.
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<br>Right !
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<br>>>>Than , of course, at a fixed (103 for Texel) rating a jib can be calculated.
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<br>Indeed, and I've there is any truth in both systems we will have a fair equalizing system.
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<br>>>For the Spi area, it’s not that big deal to me if You want to limit it 17^m,
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<br>Actually I'm proposing to make it 17,5 sq.mtr. now becuase of teh 83% rule (also 91 % RULE). This is partly caused by the fact that a aluminium standard taipan 4.9 at 108 kg is equal to F18 with this is size. But I will present a better and fully worked out case to you all, but I'm being delayed a bit by extra work caused by name change etc.
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<br>>>for the minimum weight I have more concerns:
<br>Even though it seems to be achievable when building new boats, it’s still bad news for the existing classes:
<br>In case of taipan/stealth/isotope one should buy a lot of stuff (mast/beams/rudders/daggers all carbon) . That’s hardly an option.
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<br>Indeed, well I working out a math. model right now and apart from giving my point of view I can't anything to this discussion than that you have a good point and that it needs a closer look. And I'm giving it just that.
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<br>>>is is also the reason that I’d like to see your calculations; if it is possible to compensate a slightly heavier boat with a larger jib, well than the problem is solved.
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<br>Well, I asked a befriended cat designer for help on the high speed spectrum of the cats. In the low speeds I say make effective sailarea equal to actual wettedsurface ratio. And of course at low speeds, cat width is not an issue so the smaller Isotope would not be treated unfairly in that respect. this I working on a acceptable but simple model and that will take some more time. Part of results are already presented online in the equalisation to F18 webpage. Have you seen that already ?
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<br>Regards,
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<br>Wouter
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Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands