Join Date: Feb 2000
Location: Annapolis, Md
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1976 41'''' TA CHIAO CT ??????
Like I said, there are owners who love their CT''s and then there are other. Russ raises some good and valid points. I would like to address them a bit. While it is true that I have never sailed on a CT 41 I have observed them underway. Having had ample opportunity top watch and comment on the behaivor in a short but not especially high chop and on a gusty day in winds below 20 knots, I stand by my comments that these are tender, rolly boats that tend to pitch a lot as compared to the other boats that were around it. I think that the heel angle might have been improved if with vangs on the main and mizzen but that said they showed more heel than an offshore boat should and looking at the numbers that is quite understandable.
With regard to the "capsize screening formula", as I have stated before, this is a totally useless number that tells nothing about a vessels real likelihood of capsizing or recovering. Nowhere in the formula are the real factors that affect whether a boat will capsize or recover. It does not include the big factors like weight distribution, ballast ratio and ballast location, freeboard and cabin volumes, dampening factors or excitation factors or even minor determinants like waterline beam or beam distribution.
While neither of us do have an accurate finite measurement of the vertical center of gravity relative to the center of buoyancy, there are a number of factors that do come into play here that are easy to assess. While Russ is right that the hull is very heavy fiberglass it should be remembered that the center of buoyancy is quite low in traditional designs compared to more modern designs. As a result far more of this heavy hull and deck structure occurs above the center of buoyancy than below helping to raise the center of gravity. When you add in the low density ballast, comparatively shoal draft, heavy interior appointments and wooden spars, these boats would have a higher center of gravity than I would consider ideal and their actual behaivor as observed would suggest that this speculation about their center of gravity is probably pretty close to right.
While it is true that the CT41''s spars are shorter than the taller rigs that I prefer, the height and weight of the duplication of staying and the second mast of a ketch rig generally will offset the increased height of a similar drive taller rig.
I think you are miss-using the term ''stiffness''. Stiffness really applies to form stability. A boat with too much stiffness has a quick jerky motion. But a boat that gets its stability from a low center of gravity generally has the most comfortable motion rolling at a slower rate and through a narrow angle. Heavier masts will slow the roll rate but at the same time cause the boat to roll through a wider roll angle.
The real problem with high inertial masses is excitation, a property where a series of waves roll a boat through ever wider angles of heel.
In U.S. Navy studies of seasickness, people were found to have varying susceptiblity to seasickness with nearly equal numbers of the samples more profoundly affected by roll angle and others profoundly affected by roll rate. Roll angle is a bit more tiring as it requires more muscle movement.
If carbon fiber was a cost effective and reliable as aluminum I would probably advocate its use more vociferously. But Aluminum is a very cost effective and durable material for spars and that does not seem be to be likely to change soon. For the record the first mast that I lost was a wooden mast that rotted out from the inside at the partners and I was too young to recognize the teletale signs beneath the near perfect varnish job. The second mast that I lost was an almost new aluminum spar in which the rigger forgot to install an compression tube at the shrouds. Under load the mast crimped together and down it went. This mast replaced a wooden spar that had buckled where water had gotten into the mast and rotted it out behind the gooseneck track. Again with proper vigilence the prior owner could have saved that mast. While I think that there is nothing prettier than a wooden mast, and with proper care a wooden mast can last 30- 40 years (I owned a 1939 Stadel Cutter with its nearly 40 year old wooden spars.) it takes a lot more care to maintain and a lot more ballast to support a wooden spar.
I agree that there seems to be a diversity of opinion about CT''s. Some of my opinion came from my mother, which I know sounds strange. After living on board sailboats for a number of years she and my stepfather went into the boat business starting thier own company. Working with Taiwan yards, They commissioned and developed designs, chose yards to build thier boats, oversaw development and construction, and inported the boats to the US. In those days the Oriental boat building industry was a pretty tight knit bunch so that pretty quickly you developed a sense of who was legit and building a high quality product and who was run of the mill. Ta Chiao built a range of quality products but CT''s were not terribly highly regarded. In talking about them with an experienced surveyor friend, in his words, Quality construction was not CT''s strong suit.
I have a particular gripe with the use of encapsulated cast iron scrap metal ballast. Sooner or later moisture will get to the iron, either through the bilge or capillary action through the keel and the corroding iron will pry the ballast and encapsulation appart. A boat with this encapsulated cast iron scrap ballast would be a deal breaker for me even in the days when I owned traditional boats.