CAPSIZE - 2.47 what this mean

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Apr 24, 2004
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Macgregor 24 sacandaga lake
the capsize ratio for my 1972 24 venture is 2.47, can someone give that more meaning. 2.0 is normal and the lower the better. But is 2.47 bad, and how does it compare to other boats.
 
D

Dave M26D

Here is a boat comparison calculator...

that will allow you to compare many parameters of your boat (including capsize ratio) with just about any boat made. It's easy and a lot of fun...hope it helps.
 
D

Dave M26D

and here is one that

provides a brief explanation of the various boat characterisics
 
M

MArk

More comparisons

The capsize ratio for the Venture 24 is no worse than most other boats her size (Catalina 22 is 2.53). The Macgregor 26C has a 2.24 and the 26X has a (very acceptable) 1.93 ratio. While below 2 is considered safe for coastal cruising, the capsize ratio is only one meteric to consider. What is the capsize ratio? Well it's neither an indication of self-righting ability nor heeling angle nor any other static stability. What it is is a relative tendency for the boat to roll over (capsize) when hit abeam with a large wave. The simple formula models empircal data from experiments. It is based on the dynamic forces of wave action timing and leverage provided with a wider beam versus the momentum due to the boat's mass. That's why even adding weight to the top of the mast will give a better capsize ratio (better dynamic stability) while decreasing the static stability. A boat that rolls slower (narrower beam and more weight) has a better chance that the wave will pass before the heel angle is past the point of recovery. Why was it invented? The capsize ratio was developed after a disaster as mentioned in Dave's link; the 1979 Fastnet Race storm in the Irish Sea where 15 sailors drowned and 75 boats flipped: (story on related link below) Fastnet Racing rules of the time pushed boat designers to the point of danger (wide and light). To sum up: With a capsize ratio of 2.47 you should not venture into the open ocean. More calcs and comparisons: http://www.image-ination.com/sailcalc.html Happy sails *_/), MArk
 
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