Join Date: Feb 2000
Location: Annapolis, Md
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Can a Bristol 32 Circumnavigate?
My criticism of the Bristol 32 comes from spending many hours sailing on board them, around them and against them. While I generally do not like the aberations that occured in yacht design as a result of the CCA rule, there were few production boats for which the impact was more harsh.
To address your points, while many CCA boats were designed so that their waterlines would lengthen dramatically, the shape of the bow and stern on the Bristol 32 (narrow stern with sharp exit angle) somewhat limited this as compared to other well known CCA rule beaters such as the designs by Bill Tripp and Halsey Herreshoff. In sailing Bristol 32''s it took a very large heel angle to get much to get even a small increase in speed which is why the smaller Halsey Herreshoff designed Bristol 29 rates significantly faster than the Bristol 32 and the Cal 25 of the same period rates equal. In this case, based on my experience with these boats, the short waterline is exactly the problem that I make it out to be, unless passage times just do not matter to the person who originally asked the question. After all, I point out that these boats are slow even compared to many of their contemporaries but I leave it to the person asking the question to determine whether that bothers them.
Beyond that, as I mentioned it takes a large heel angle on the Bristol 32 to have much impact on speed, as heel angles increases so does leeway. But if we look at the original question, (i.e. is the B32 suitable for a circumnavigation) these larger heel angles would make them less suitable as an offshore boat than a boat that did not need to sail at such large angle of heel to have reasonable performance.
As to the weight carrying issue, you really need to look at the factors that influence the impact of carrying weight on a boat. D/L really is a very small determinant. In reality, it is true that there is some relationship between the amount of carry capacity and the dry weight weight of the boat. As a rough rule of thumb, most boats can carry approximately 1/4 to 1/3 of their dry weight in gear, supplies and tankage without having an extremely adverse affect. In that sense a heavier boat in theory can carry more weight.
BUT there are other very significant factors as well. One of the big factors is waterline plane. (The physical area, not volume, of the boat at the waterline.) The larger the area the less the boats will settle in the water for a given load added. Boats that achieve a high D/L by having a short waterline can either achieve the high D/L by having a lot of waterline beam, full ends or a deep canoe body. Boats with lots of waterline beam tened to have quick motions and are therefore not very good for offshore work. Boats with full ends tend to be wet and slow and very poor to windward. And boats like the Bristol 32, which have neither a lot of waterline beam or full ends, tend to have deep canoe bodies which means that they have comapatively small waterline plains. That means they tend to immerse more quickly and pick up drag more quickly than a boat with an equal displacement but a longer waterline. For an equal displacementa boat with a longer waterline will tend to have less waterline beam, finer ends, shallower canoe body and a greater waterline plain. This is the reason that traditional watercraft that worked offshore (as well as more modern designs) had very long waterlines compared to race boats (such as the Bristol 32) of the CCA era.
So, in general, if you take two 32 foot boats of equal dry weight displacements and one had a 21 foot waterline and the other a 27 foot waterline, the boat with the 27 foot waterline will have far superior ability to absorb additional weight with less negative affect on speed, stability and motion than the boat with the shorter waterline.
Another factor that affects how much weight a boat can absorb is sail area to displacement. Boats of the CCA era were disproportionately penalized for stability and working sail area. As a result they carried less sail area for a given displacement and were comparatively tender when compared to more traditional or more modern designs of equal displacement. If you add weight to a boat with a low SA/D there is proportionately less sail area to overcome the inertia of this greater weight.
You are right that there are plenty of boats out there that have high D/L''s that are good in a chop. These are generally comparatively long waterline boats when compared to the CCA era race boats. This longer waterline reduces pitching and when combined with a finer bow, reduces the bow''s impact with waves. Boats like the Bristol 32 tend to hobby horse when dealing with a chop which is neither comfortable for the crew nor is it conducive to good speed through the water.
If you ask me what a Bristol 32 is good for, I would say that they are good for what they were designed to be, coastal cruisers in areas with typical winds in the 10 to 20 knot range for a person who is on a limited budget and does notcare about speed. I still sail on boats of this era, and find them fun to sail as long as we are not trying to get somewhere too far away. Going around the world is too far away for this boat in my book.
So as to the unfair opinion, I too am getting weary of having my opinions judged unfairly, without you stopping to analyze what has been said or why I said it.