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Just a quick observation about lifting keels: there are two opposite approaches to these. To keep ballast as low down as possible, some lifting keels are heavy, like a fixed keel. At the opposite end, the solution is a virtual "centerboard" like a dinghy. Both regards maintenance and safety these are radical opposites.
The heavy solution ought to have characteristics similar to a fixed (fin?) keel, although there may be some compromise in aerodynamic shape in order to fit it in the upright position. Obviously, the weight requires complex mechanical systems for lifting, often hydraulic. Such a system requires maintenance, and my personal fear would be what happens if it should fail - we have seen the Volvo Ocean racers and other boats with mechanical canting keels turn into real disasters.
The alternative, a light centreboard, does not get ballast as low down. On the other hand, it has a huge maintenance advantage. On my (Ovni 395) the weight is 80kg and I lift it with a thin rope, no assistance or mechanical complexity. I love it. Additionally, this light keel will tilt back if you hit ground, and you can in most cases sail on without any damage.
In my view, the second advantage of the light centreboard is that the ballast is instead part of the boat - several tons of lead baked into the bilge. Therefore, it makes absolutely no difference to stability whether the keel is up or down - worth remembering for those who swear by fixed keels and count on not losing them...
Many years ago, I was working with a boat builder who built lifting keel boats with keels of the heavy variety, and our experience with hydraulics and the heavy-duty pivoting systems associated with a heavy keel were not encouraging; I would be quite fearful of owning one of those.
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