does anyone know the "capsize screening value" for the Cape Dory Typhoon? also is it possible to capsize a Typhoon in heavy winds( 25 knots ) with full main and standard jib set? I'm new to sailing and a little bit white- knuckled when my Typhoon puts her rail under.
donjoecam@aol.com
typhooncapsize screening value
Moderator: Jim Walsh
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JB
Re: typhooncapsize screening value
Did you mean screening value or screaming value? Just a joke.
You can capsize a typhoon in a 25 knot breeze but most likely you will just be knocked down until the wind spills off the top of the sails. We experienced this one time and just eased the main and jib sheets. It can be harrowing. The point of capsize is that with wave motion the knock down could lead to a capsize. "When you are contemplating to reef or haul in sail, do it." This will provide you with a less exciting sail until you learn what your boat will take and what is wreckless and dangerous. In 25 knots, I start out with a reefed main and the jib hanked on. I try to reef the main to the point that I can fly the jib, depending on direction of sail. A downwind sail in a nice breeze like 25 kts is great under a working jib alone if you don't want to worry about the jybe.
Take your time and take it easy. You'll get it and enjoy your typhoon, the best small boat out there.
JB
You can capsize a typhoon in a 25 knot breeze but most likely you will just be knocked down until the wind spills off the top of the sails. We experienced this one time and just eased the main and jib sheets. It can be harrowing. The point of capsize is that with wave motion the knock down could lead to a capsize. "When you are contemplating to reef or haul in sail, do it." This will provide you with a less exciting sail until you learn what your boat will take and what is wreckless and dangerous. In 25 knots, I start out with a reefed main and the jib hanked on. I try to reef the main to the point that I can fly the jib, depending on direction of sail. A downwind sail in a nice breeze like 25 kts is great under a working jib alone if you don't want to worry about the jybe.
Take your time and take it easy. You'll get it and enjoy your typhoon, the best small boat out there.
JB
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Don
Re: typhooncapsize screening value
JB I really meant screening value but will settle for screaming value. I accidentally saw the term"capsize screening value" while viewing the specs for the Allied "Greenwich" 24 which was the predecessor of the Cape Dory 25. It had a value of 1.85 and the specs stated that a lower value meant a more stable boat "the screening value must be under 2.00 in order to be offshore capable".
I have not heard the term before and thought it might be reassuring to know the screening value for the Typhoon.
Thanks for your advice.
Don
donjoecam@aol.com
I have not heard the term before and thought it might be reassuring to know the screening value for the Typhoon.
Thanks for your advice.
Don
donjoecam@aol.com
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Catherine Monaghan
Re: typhooncapsize screening value
The capsize risk factor for both the Typhoon and Typhoon Sr is 1.93 according to John Holtrop's fuzzy logic. (http://www1.iwvisp.com/jholtrop/default.htm) Anything less than 2 is desirable.
If you subscribe to Cruising World, the April 1998 issue has an article by John Holtrop called "Crunching Numbers for a Quality Cruiser." It is well worth reading and explains what all the numbers mean.
catherine_monaghan@merck.com
CD32 Realization
catherine_monaghan@merck.com
If you subscribe to Cruising World, the April 1998 issue has an article by John Holtrop called "Crunching Numbers for a Quality Cruiser." It is well worth reading and explains what all the numbers mean.
catherine_monaghan@merck.com
CD32 Realization
don wrote: does anyone know the "capsize screening value" for the Cape Dory Typhoon? also is it possible to capsize a Typhoon in heavy winds( 25 knots ) with full main and standard jib set? I'm new to sailing and a little bit white- knuckled when my Typhoon puts her rail under.
catherine_monaghan@merck.com
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Paul R. Mitchell
Re: typhooncapsize screening value
I got the following from http://www.herringn.com/how/boats/ratios.html :
"The Capsize Screening Formula was developed by the U.S. Sailing Association as a rough rule of thumb, helpful in comparing the initial resistance to capsize of various boats. Boats with a Capsize Screen factor of 2 or less will have a normal initial resistance to capsize and will in general be safer offshore boats than boats which exceed this value. The lower the value, the better, all other things being equal."
Also, http://www.anyboat.com/capsize.htm has a capsize screen calculator that calcultes the value based on the following definition:
" According to the capsize formula published in the May 1997 issue of Practical Boatowner, anything less than 2 is considered "good". If you would like to find the capsize "value" of your vessel divide the displacement of the vessel by 64, then take the cube root of that number and divide into the beam of the vessel, or just use the form below! Just a word of caution, anyboat does not recommend the use of any one formula for determining vessel stability or if a vessel's design is seaworthy."
For a typhoon weekender, I get:
"The capsize value for your boat of displacement 1900 pounds and maximum beam of 6.25 feet is 2."
I hope this helps,
Paul
prmitch@ix.netcom.com
"The Capsize Screening Formula was developed by the U.S. Sailing Association as a rough rule of thumb, helpful in comparing the initial resistance to capsize of various boats. Boats with a Capsize Screen factor of 2 or less will have a normal initial resistance to capsize and will in general be safer offshore boats than boats which exceed this value. The lower the value, the better, all other things being equal."
Also, http://www.anyboat.com/capsize.htm has a capsize screen calculator that calcultes the value based on the following definition:
" According to the capsize formula published in the May 1997 issue of Practical Boatowner, anything less than 2 is considered "good". If you would like to find the capsize "value" of your vessel divide the displacement of the vessel by 64, then take the cube root of that number and divide into the beam of the vessel, or just use the form below! Just a word of caution, anyboat does not recommend the use of any one formula for determining vessel stability or if a vessel's design is seaworthy."
For a typhoon weekender, I get:
"The capsize value for your boat of displacement 1900 pounds and maximum beam of 6.25 feet is 2."
I hope this helps,
Paul
don wrote: does anyone know the "capsize screening value" for the Cape Dory Typhoon? also is it possible to capsize a Typhoon in heavy winds( 25 knots ) with full main and standard jib set? I'm new to sailing and a little bit white- knuckled when my Typhoon puts her rail under.
prmitch@ix.netcom.com
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D. Stump, Hanalei (CD-30C
Re: capsize screening value for all
Don,
According to Paul's formula and the Displacements and Beams listed in the CD-30 owners manual the Capsize Screening value for the following is:
TYD = 2.03 CD-27 = 1.73
TYW = 1.98 CD-28 = 1.71
CD-22 = 1.98 CD-30C = 1.67
CD-25D = 1.85 CD-30K = 1.67
Result is: Cape Dory Sailboats are generally very stable vessels, but we all knew that from experience! There's nothing like 25 knots of wind with all her flags flying, leward rail buried in foam and water flying over the bow on a close reach! (I guess you can tell, I don't want to pull Hanalei out on the hard just yet!)
Fair winds & following seas.....
Dave Stump
Captain Commanding
Hanalei
stumpdg@gwsmtp.nu.com
According to Paul's formula and the Displacements and Beams listed in the CD-30 owners manual the Capsize Screening value for the following is:
TYD = 2.03 CD-27 = 1.73
TYW = 1.98 CD-28 = 1.71
CD-22 = 1.98 CD-30C = 1.67
CD-25D = 1.85 CD-30K = 1.67
Result is: Cape Dory Sailboats are generally very stable vessels, but we all knew that from experience! There's nothing like 25 knots of wind with all her flags flying, leward rail buried in foam and water flying over the bow on a close reach! (I guess you can tell, I don't want to pull Hanalei out on the hard just yet!)
Fair winds & following seas.....
Dave Stump
Captain Commanding
Hanalei
stumpdg@gwsmtp.nu.com
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Neil Gordon
Re: typhooncapsize screening value
>>"When you are contemplating to reef or haul in sail, do it." This will provide you with a less exciting sail until you learn what your boat will take and what is wreckless and dangerous.<<
Is the objective to max speed or max the excitement? I find that reefing early and reducing the weather helm keeps the boat at hull speed in a good breeze well before the rail is in the water. I generally put a reef in just when the whitecaps start, about 17-18 knots, I guess. I did a beam reach this way from Plymouth, MA to Provincetown (with a full genoa) and *averaged* better than 6.5 knots, as measured buoy to buoy, not by the speed log. This is after taking into account my bad steering, etc. Wind was about 20 knots and the seas 3-5 right on the beam. The boat was never over more than 15 degrees.
Regards, Neil
s/v LIQUIDITY
Cape Dory 28 #167
103355.34@compuserve.com
Is the objective to max speed or max the excitement? I find that reefing early and reducing the weather helm keeps the boat at hull speed in a good breeze well before the rail is in the water. I generally put a reef in just when the whitecaps start, about 17-18 knots, I guess. I did a beam reach this way from Plymouth, MA to Provincetown (with a full genoa) and *averaged* better than 6.5 knots, as measured buoy to buoy, not by the speed log. This is after taking into account my bad steering, etc. Wind was about 20 knots and the seas 3-5 right on the beam. The boat was never over more than 15 degrees.
Regards, Neil
s/v LIQUIDITY
Cape Dory 28 #167
103355.34@compuserve.com
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Dick Sisson
Re: typhooncapsize screening value
>>...also is it possible to capsize a Typhoon in heavy winds( 25 knots ) with full main and standard jib set?<<
Based on experience with my Ty Weekender, my opinion is that a capsize would be unlikely in the above conditions. Rail at the water isn't a big deal and is quite exhilerating if you like a little excitement, and is easy to do with this boat as you get some seat time. Beyond rail at the water and say in the area approaching 45 degrees of heel the boat begins to fail to make progess to windward, it just lays over on its side quite stabally.
My opinion is that Carl Alberg, in his genius, designed the boat to be very resistant to knockdowns.
dickee03@rivnet.net
Based on experience with my Ty Weekender, my opinion is that a capsize would be unlikely in the above conditions. Rail at the water isn't a big deal and is quite exhilerating if you like a little excitement, and is easy to do with this boat as you get some seat time. Beyond rail at the water and say in the area approaching 45 degrees of heel the boat begins to fail to make progess to windward, it just lays over on its side quite stabally.
My opinion is that Carl Alberg, in his genius, designed the boat to be very resistant to knockdowns.
dickee03@rivnet.net