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Old 06-04-2013
bobperry bobperry is offline
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Re: Bob Perry's take on Wolfenzee's dream boat

Hello:
Your terminology is just fine.
In a word, no. You can run a new VPP with the adjusted VCG and that will give you the new stability and speed data but one of the Achiles Heels of the VPP is that it does not factor in waves. I suspect that an office like J/V or Farr may have a proproetary VPP that might allow wave data to be input but I've never heard of any office having it. That is also the reason that the VPP can't simulate surfing conditions to predict when a boat might break free and plane or semi-plane.

However, in some test tanks you can tow a model in different seas to test the effect of a change in VCG. The problem in a towing tank is that you tow a scale model but you can;t scale down the way waves behave. That was the problem behind the classic tank error that lead to the infamous MARINER 12m stern. The model looked fine in the tank. The real boat did not look so fine in the bay.
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