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post #6 of Old 03-18-2002
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1976 41'''' TA CHIAO CT ??????

We need to separate fact from fiction here. Jeff, who is very knowledgeable, has made several assumptions about CT''s that are incorrect, in our opinion. Perhaps he has not sailed on a CT41. His conclusions follow from his arguments, but his arguments do not apply to CT41''s.

Jeff claims that a boat "with 32% ballast to displacement ratio, low density ballast, on a short waterline ... high center of gravity of a wooden sparred boat ... is not an offshore boat....". He goes on to state, "Those kind of numbers suggest a rolly boat with relatively poor stability".

Our problem with Jeff''s conclusion is that the boat is not rolly, does not hobby horse, gives a stable ride, and performs quite well given modest winds. Why the discrepancy between Jeff''s expectations and reality, one may ask?

First, the only number Jeff cites is the 32% ballast to displacement ratio. Nigel Calder recommends a ballast ratio of 0.3 as a lower limit. However, this ratio, by itself, is insufficient to determine stability, as Jeff has eloquently argued elsewhere. If this ratio told all, life would indeed be simple. A better measure of stability is the "capsize screening formula" which can be looked up in most good cruising handbooks. The CT41 at 1.6 easily passes this measure of stability (less than 2.0).

Jeff assumes that a CT41 has a high center of gravity, partly because of the low density ballast and because of wooden masts, which are heavier than aluminum masts. Neither he nor we know the distribution of mass for a CT41, but I have several observations that contradict his assumption of a high center of gravity. Firstly, the hull is solid fiberglass and is quite thick by todays standards. This implies that a lot of mass is distributed relatively low, particularily compared to cored hull boats, the type Jeff favors. Secondly, fuel and water tanks and other heavy structures are located relatively low on the centerline in the heavy displacement ratio CT41. A light displacement ratio boat doesn''t have the shape or room on the centerline to place weight as low. Thirdly, while lead ballast is generally superior to scrap iron, there are many successful cruising boats using encapsulated scrap iron ballast. Lastly, there is the question of wooden masts. True, they are approximately 25% heavier than aluminum masts. But, the CT''s wooden masts are not nearly as tall as in the high aspect ratio sail boats Jeff favors and, therefore, the smaller wind heeling moment is sufficiently balanced by the scrap iron ballast. Of course, if mast weight were as important as Jeff implies, he would advocate only carbon fiber masts which are another 25% lighter than aluminum. The problem with this ever lighter structure is that at some point the boat becomes too stiff and has an uncomfortable motion. The weight of the masts provide the rotational moment of inertia that is needed for dynamic stability. Yes, if you lose your masts, your boat is more dynamically unstable and more subject to capsize in heavy weather!

As to the quality of the Ta Chiao yard, we have heard conflicting stories. Our surveyor, a rather knowledgeable person, had some good words to say about boats that he has surveyed that came out of the Ta Chiao boatyard.

We agree that wood spars are best coated with varnish or a varnish substitute. If you are planning to buy a boat with wooden spars, be sure to hire a surveyor who is experienced at inspecting wooden masts. Remember, wood rots and aluminum corrodes. If I remember correctly, Jeff has lost two "aluminum" masts. Perhaps he will tell us the stories some time.

In our opinion, CT''s make excellent cruising boats.

Russ & Cynthia
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