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post #1 of Old 08-17-2013 Thread Starter
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Why the Bristol 32 backs so poorly

I've been playing with the Bristol 32 and comparing its performace to other boats I've sailed like the Catalina 27 and 30.

I think I have a theory I would like to explore with those of you knowledgeable about these things.

First the behavior I'm trying to understand.
With the Catalina's putting the boat in reverse caused the stern to prop walk to the port. Once it has way on it could be steered in reverse pretty well.

With the Bristol the behavior is reverse seems to be random, it obviously is not which I why I'm doing this exercise. Sometimes the stern will kick port sometimes starboard. Often when is reverse the boat will not steer based on the helm but will choose its own path.

I think I may have an answer.
If you look at the underwater profile of the boat most of the keel is under the wheel. The forefoot is cut away. I'm thinking that while a fin keel boat pivots someplace near the mast in either forward or reverse the Bristol pivots nearer the wheel in reverse.

I think that what is happening is that in reverse the bow is very easily blown downwind or down current turning the boat in a much more effective way than the prop walk or rudder.

In order to predict what the boat will do in reverse I have to think in terms of how the current and wind will move the bow much more than in a fin keel boat.

What do you think?

The lesson from the Icarus story is not about human failing.
It is a lesson about the limitations of wax as an adhesive.
If you have an engineering problem solve it.
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