Freeboard Deleterious Effects?

[F.H.B.]

Happy New Year

Is there some way to calculate how much effect adding freeboard will have on a 48' boat. There are two designs. One has 18" less freeboard which makes it easier to board, but the higher one has much better accommodations.

I don't suppose there is a calculation that says, "for this beam, length, freeboard, and other information it will sail this close to the wind." What else might be an issue wit more freeboard?

Many Thanks,
- J

 

[EsoxRanger]

Re: Freeboard Deleterious Effects?

What else might be an issue wit more freeboard?

Raising the center of gravity.

 

[pmillar]

Re: Freeboard Deleterious Effects?

There are all sorts of equations for calculating stability, etc. that naval engineers/architects use. (My brother is a naval arch/eng.) You would need to hire somebody for that exercise... which would still involve some guess work unless the factory could help you out. Experience counts for something too (thinking builders here)

 

[smokeonthewater]

Re: Freeboard Deleterious Effects?

ok so deleterious IS a real word.... had to look it up...... for us cavemen it means BAD...lol

 

[F.H.B.]

Re: Freeboard Deleterious Effects?

ok so deleterious IS a real word.... had to look it up...... for us cavemen it means BAD...lol

Think of it as one word down for the word of the day New Years Resolution you have been wanting to take on

Thanks for the replies, all. I know the two plans are stable - Benford designs. I am now mainly wondering for the same length of boats would more freeboard cause less ability to go to windward and if so, how much.

For that matter, could one put a keel on a big power boat design with massive freeboard in order to lower the CG, stick sails on it, and at least get places engineless even if not in a "performance" way?

Hmmm....

 

[smokeonthewater]

Re: Freeboard Deleterious Effects?

I like the word... I plan on using it to annoy my fellow cavemen...
as I understand it freeboard is the height of the deck above water level? is your concern with wind resistance of the hull itself? I'm not sure if something's missing or if this concern is something sailboat specific that I've never heard of

 

[grego]

Re: Freeboard Deleterious Effects?

Not sure? any time you change the cg, "center of gravity" you move the "moment arm" forward or aft.

 

[F.H.B.]

Re: Freeboard Deleterious Effects?

I like the word... I plan on using it to annoy my fellow cavemen...
as I understand it freeboard is the height of the deck above water level? is your concern with wind resistance of the hull itself? I'm not sure if something's missing or if this concern is something sailboat specific that I've never heard of

Yep. My concern is wind resistance. I would love a design that has full height living space under a full height coach house. That is one big sail that can't be taken down. It doesn't have to perform - it just has to get us places in the world. I have seen a couple of plans but they are 64' long. I want 50 or less. Some folks have said it can't be done as it will not sail any more. Come on! Look at the grand poop decks of Brittish Naval traditions and so forth.

 

[EsoxRanger]

Re: Freeboard Deleterious Effects?

Come on! Look at the grand poop decks of Brittish Naval traditions and so forth.

The ships that the Brits sailed when they said the Americans were cheating when it came to battle on the high seas, because our frigates were sailing circles around them and ripping them to shreds?

 

[F.H.B.]

Re: Freeboard Deleterious Effects?

The ships that the Brits sailed when they said the Americans were cheating when it came to battle on the high seas, because our frigates were sailing circles around them and ripping them to shreds?

LOL! Too true! Sail all the circles you want around me, however, as long as I can get places with a TON of family space in a short design