Ratio's ???

[Frank]

Great site to 'punch in your #'s'. Remember...higher MCF and lower CSR are better. When you pull up the site...scroll down,enter your #'s and hit 'compute'...it's instant..scroll down slightly for results.I was pleased to find my 1962 25.5ft pearson Ariel has BETTER #'s than my new 02 Beneteau 331 had !!! Alberg was a great !! Even his lil 18ft 'typhoon' has good #'s !!  Check out your boat and compare. http://www.image-ination.com/sailcalc.html

[starcrest]

the only ratio I ever herd of was in a history class something about a "captain ratio hornblower"anyone eva hoida him????

[CharlieJ]

Frank- I've played with that site quite a bit, and find it really great. Really interesting to see the close match up between my Meridian 25 and the world famous "Folkboat" Rhodes had a helluvan eye also- perhaps even moreso when it comes to sheerlines  ;s)

BUT-

Bear in mind that all the info there is stuff that has been provided by people coming to the site. There COULD be errors or inconsistencys in the figures provided. I haven't seen any so far, but the possibility exists

[captedteach]

I think that site gives a good overall view of a boats perceived  preformance but I think it can have some large errors when you look at real world numbers   I compaired the numbers for a Cal 25 and a SanJuan 23  Two boats that I own right now -  the theoretical hull speed is listed as 5.99 for one and 6.00 for the other with the SJ 23 being faster.  I know the Cal sails easily at 6knts and there is a picture in the gallery of my knot meter at 7.5 knots (dpn from US Sailing list my Cal at 91.5)   I have yet to sail the SJ 23 but its DPN is 98.1  From sailing a Hunter 23 with a DPN of 96.3 and knowing that I can sail 20% faster than it, the SJ23 should be about 25% slower than the CAL when I get it on the water.  MAYBE it just has not been campianed very much hence the low rating but I am not sure.  I will try to update when I have both boats on the water this summer

[Frank]

Real world will differ for sure ...particularly in 'speed'.  2 boats with the exact same waterline length will have the same theoretical hull speed.One has a high lift fin keel and rudder , wide beam,long flat run aft.The other a full keel,narrow beam and long overhangs. Obviously the the first boat will point higher and be very fast off the wind....BUT...will pound like heck in a chop,not carry her 'way' as well and 'stall' in big waves and although will show high initial stability ,will have limited ultimate stability and therefor not be that good for offshore where it is not a question of 'IF' you run into gale but 'WHEN'. The 2nd boat will carry her 'way' better in a chop,not pound near as much and although seem initially a bit tender,will have high ultimate stability. Thats where playing with the numbers is fun...compare the MCf and CSR as well as hull speed from boat to boat. The higher the MCF the better...25 and up is good...35 and up exellent.  Then CSR...lower the better...2 is minimum for offshore (generally excepted) 1.9 is better , 1.6 exellent and so on. Theoretical hull speed is only part of the numbers game. My 25ft6in Alberg designed Pearson Ariel has better 'offshore numbers' than my former Beneteau 331 (33ft11in) although obviously not the same hull speed