Boat Design Forums  |  Boat Design Directory  |  Boat Design Gallery  |  Boat Design Book Store  |  Thanks to Our Site Sponsors
Old 06-19-2009, 10:26 AM
TeddyDiver's Avatar
TeddyDiver TeddyDiver is offline
Join Date: Dec 2007
Rep: 1650 Posts: 2,506
Location: Finland/Norway
Well most of the time anyway allthough having a possibility to dump some is allways there..
It's 33' motorsailer 6.5t fully loaded, longkeel 1500kg lead +800water, gaff ketch. Got some pictures in the Gallery. For drinking water separate 2x250l tanks.
Reply With Quote
Old 06-18-2015, 04:32 PM
yam_fzr yam_fzr is offline
Junior Member
Join Date: Mar 2015
Rep: 19 Posts: 12
Location: Australia
Sorry about raising the dead but it seemed pointless to start a new one when correcting an issue presented as fact by a World renowned designer as the OP.

Originally Posted by Richard Woods View Post
Or put it another way

It is extremely rare for a cruising catamaran to capsize in waves with no sails set (trimarans are a different matter) because despite what the media say, waves over 20ft high (the average beam of most ocean going multihulls these days) only occur in F10 conditions or more.
This is incorrect as the following nomogram shows:

Wave height nomogram

The fetch and wind speed given the appropriate duration determine the wave height. So for a short duration squall, yes, you are correct. For a long constant blow, waves can exceed 20 feet in surprisingly low wind speed, 30 knots for about 26 hours will do it. So an F7 for just over 24 hours gets those wave heights.
Likewise, 4 hours in 80 knots will get you 20 footers.
Some of the more interesting aspects to this are in the trade winds. If they are blowing a bit higher than normal, say 26 knots then it won't take long to get 20 footers if the wind picks up to say 40 knots , it's about 12 hours.
Reply With Quote

Old 06-28-2015, 02:42 PM
ThomD ThomD is offline
Senior Member
Join Date: Mar 2009
Rep: 111 Posts: 521
Location: TO
As far as the unsinkable mono is concerned it is as much as anything confirmation that the regulators think as the multi designer, that not augering into the ocean floor is a good idea. But that said there are different degrees of floatation in a storm a multi can remain high in the water with liveability, I just don't see how a mono with aggressive sailing capacity can flood and float, and remain liveable, and with modern communications that may not be the issue it once was.
Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Similar Threads
Thread Thread Starter Forum Replies Last Post
Sink Drains And The Romans Sean Herron All Things Boats & Boating 1 04-08-2009
10:51 PM 
Installing a swim platform awol46 Wooden Boat Building and Restoration 11 01-02-2007
04:12 AM 
swim deck fiberglass jack Marketplace 1 03-15-2006
06:00 PM 
Portager swim step and davit Portager Boat Design 8 03-12-2005
05:03 AM 
Galley Sink ahasiec Boat Design 0 02-08-2005
09:34 PM 

Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.

All times are GMT -5. The time now is 03:17 AM.

Powered by: vBulletin Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Web Site Design and Content Copyright ©1999 - 2017 Boat Design Net