hey all
just wondering if there is a formula out there that can tell you how stiff a design will be…
basicly we all know anything under the waterline is a plus and anything above the waterline is a negative. right???
so the wieght of the mast will want to pull the boat over. the heavier the bulb/keel will keep the boat upright.

so is there a formula for say stiff= above wtl/under wtl=3( i just pulled that number out of the air) and 3 makes a stiff boat… where as 1 one be a tender boat. 5 means the boat wont heel at all

Hi Cougar,
I suppose you miss the tread about J Class vs 12Metres where this aspect was often treated.
There is explained how to calculate the bulb weight.
From my experience searching for real conditions is far too complex therefore I use a simplified method based upon the Bernoulli Law that is applied to a static condition without considering various variables like wind directions, wave height, etc… If the method may appear not very precise, (still to be proved) it is also true that is not very wrong either and in any case if mistakes exists are applied similarly to all configurations. (constant error)
Interesting reading about Force on Sails : http://en.wikipedia.org/wiki/Forces_on_sails
Best
ClaudioD

Hi Cougar,
I suppose you miss the tread about J Class vs 12Metres where this aspect was often treated.
There is explained how to calculate the bulb weight.
From my experience searching for real conditions is far too complex therefore I use a simplified method based upon the Bernoulli Law that is applied to a static condition without considering various variables like wind directions, wave height, etc… If the method may appear not very precise, (still to be proved) it is also true that is not very wrong either and in any case if mistakes exists are applied similarly to all configurations. (constant error)
Interesting reading about Force on Sails : http://en.wikipedia.org/wiki/Forces_on_sails
Best
ClaudioD