View Full Version : Novice Thoughts on Stability


Seafra
08-28-2006, 02:31 AM
I'm coming at this as a sailing novice but I'm trying to put together an working concept of true ocean-going stability.

Would the ideally stable monohull sailboat have a relatively small amount of beam per length(enough to maintain static stability), a steel hull to increase it's displacement, a fiberglass/composite cabin construction to keep the COG low, and a shallow draft twin keel(in a 90 degree split at the beam), tall narrow fuel tank on port, and tall narrow freshwater on starboard. From what I can tell, this should result in a vessel with great dynamic roll stability but relatively poor handling characteristics

Talking about keels can be like talking about religion I'm sure- but the twin keel seems to offer some good advantages from a cruising aspect though I can't image a racer much appreciating the extra wetted surface. My only hangup is that a twin keel gives me the sense that once a boat has turtled it would contribute to it's inverted stability rather than self right. I very easily could be wrong though.

Also, could someone please attach a pic of a bilge keel so I can figure out what it is? Is it synonymous with full keel designs?

More questions to come....

GregW
08-28-2006, 08:58 PM
For a short discussion on bilge keels go here:http://www.boatbuilding.com/article.php/advantagesoftwinkeels

MikeJohns
08-29-2006, 06:34 AM
Seafra
You might like to read much of what we discussed here:

http://boatdesign.net/forums/showthread.php?t=5315&highlight=twin+keel

Cheers

Seafra
08-29-2006, 09:27 AM
Thanks for the articles, guys. Great reading all around.

Twin keels seem to offer great advantages at the cost of tank time. It seems that anyone could throw on a twin keel system and call it a day- but to have a design that gives you the fluid advantages in relation to hull speed and handling...that's where the art/science hybrid comes in.

It's interesting how little thought the idea geats on this side of the pond.

knowme
04-02-2007, 11:17 AM
Thanx for the articles. I was wondering if there were any hydrostatics excel sheet available in this forum.

View Full Version : Novice Thoughts on Stability