Big Volume Stability

[sparau]

Hello all, (newb alert btw. just trawling for ideas, i don't have time to do all these things myself yet)

While internet tyre kicking i came across this,

footpath that has been floating longer than 50% of the world's population has been alive

I was just reading the post about the Formosa 51, with the comment

Originally Posted by VirtualVagabond

But it's horses for courses. They sail exactly the way they were designed to. They are a long keel, heavy displacement boat, so they sail like a long keel heavy displacement boat.
They don't point like a fin keel greyhound, but when the conditions are getting heavy and the greyhounds are wimpering, they're the St Bernards saying 'what's the problem?'

My thoughts are that a heavy boat "should" be more stable into the wind and would almost certainly be more stable at anchor than a foam core lightweight.

After a certain point of wave size the displacement of the boat becomes less important as the pure mass of the water moving becomes far greater than even the 25,000kg of these boats. I would imagine (i have no experience here) that once you have a 10-15ft swell the heavy displacement boats are moving quite a lot and the sea handling (i guess basically hull shape and what sails are deployed) capabilities become far more important.

Clearly quite a lot of the way a boat will behave will depend on where it stores it's weight plus there's some nagging idea that it should become more important in a monohull as it rises for size.

Are these the thoughts that put off possible footpath or custom purchasers? Would you expect a formosa that on the surface has similar characters to behave differently? Shane

[denverd0n]

Not quite sure I understand what you're asking. Are you wondering why this particular boat has not sold? Why other custom-built boats don't sell quickly?

I think it is almost axiomatic that boats with similar characteristics (hull shape, displacement, ballast ratio, etc.) are going to behave similarly. And boats with dramatically different characteristics are going to behave differently.

[sparau]

Originally Posted by denverd0n

Not quite sure I understand what you're asking. Are you wondering why this particular boat has not sold?

No, not at all. It has only just come up for sale and i think i could have fun with it, good luck to the seller, its a lot of boat for the money.

Originally Posted by denverd0n

Why other custom-built boats don't sell quickly?

Yes, in how do you tell in a custom boat what the balance point of stability is when there is so much mass ?

Originally Posted by denverd0n

I think it is almost axiomatic that boats with similar characteristics (hull shape, displacement, ballast ratio, etc.) are going to behave similarly. And boats with dramatically different characteristics are going to behave differently.

ballast ratio i suppose is what i am trying to get to.

[TeddyDiver]

The ballast ratio is not the only affecting thing. Water plane area is much more significant what comes to stability IMHO, butnot sure either what you are actually asking?