Addressing the original poster's question :
It's not easy to find reputable statistical comparisons of accidents and fatalities for
monohull and catamaran ( or
multihull ) sailing
boats. Chris White's book The Cruising
Multihull still appears to be the most readily available summary of this kind of information. His conclusion was 'During the five year period from 1983 to 1987, there were no reported cruising multihull fatalities in the U.S. or adjacent waters. Going back another five years, there were two reported fatalities in the 10-year period 1978-1987 inclusive. ...taking the number of
boats into account, one fatality annually for every 16,250 multihull sailboats 25 feet in length. This fatality rate is somewhat lower than the rate for
monohull auxiliary powered sailboats 25 feet or longer, which the US Coastgurd shows as being one death per 12,500 boats annually ( average value for the period 1978-1987).
US Coastguard statistics show vessels 40' and over have significantly lower death rates than shorter vessels.
Link to downloadable Coastguard data :
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Note how high operator error is on list of
accident causes and how few, relatively are the number of sailboat deaths.
A 40' cat will be a better choice than a shorter one for many reasons, assuming that the owner's
budget is adequate to meet the higher
maintenance costs and the vessel can be kept in good
seaworthy condition. Much better living space at sea and whilst moored, particularly when waiting out the unexpected bad
weather /
parts delivery or
repair delay / need to top up funds etc. And that bears on the psychological
health necessary for the task, not to mention happiness / fun quotients.
Longer hull length, wider max beam, greater designed
displacement than smaller craft = better seaworthiness, resistance to
capsize, operating comfort and efficiency in greater range of sea-states. Around 40' is a good compromise between the seaworthiness factors and man-handling factors. Going too large can take you beyond your physical abilities. What happens when the
electric anchor winch fails, the
furling gear fails, you have to go up the
mast, you go aground etc?
Cat vs mono? The cat wins on grounds of capsize survivability;
collision survivability due to preservation of buoyancy by compartmentalization of structure;
maintenance of operator efficiency due to low angles of heel (captain's cock-ups list very high on
accident causes); lower risk of injury and man
overboard due to lower angles of heel and much less violent motion. The cat is far less likely to injure you than the mono and relatively small injuries - broken finger / toe / wrist/ banged
head can be the beginning of serious trouble, never mind being downright unpleasant.
Regarding severe
weather, a well designed cat is going to be a much better place to be than a well-designed mono. Deploy a parachute
sea anchor and sit it out.