Join Date: Feb 2000
Location: Annapolis, Md
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Best Centerboard Designed Boats
Properly designed and all other things being equal a daggerboard with a bulb should do as well or better than fin keeler. The only example that I know of was a Melges 24 that took to the ground at speeds thought to be in excess of 8 knots. The description that I heard was that she hit hard and with the large chute up, spun and took a hard down which carried her over the hump. Damage was described as cosmetic.
I don''t think that is a representative fair sampling of the concept. I suspect that depending on the design of the boat and the nature of the grounding there could easily be more extensive damage to the drop keel or its scabboard.
Modern daggerboards with bulbs are next to non-existent in larger production boats but they are a concept that I would love to see more often. It is comparatively easy to design a structure that could absorb the engery of a major impact. It might include a large rubber impact block that could take buffer most of the force of impact rather than deliver the loads into a rigid structure. Longer than usual leverage into the boat perhaps with SS tubes sliding an a SS scabboard could also reduce the loads felt by the boat. I had designed a quick release lock down system that would permit the keel to be released under pressure allowing it to be retracted when aground but which would automatically engage if the boat took a knockdown, locking the keel so that it can''t retract due to gravity. If I were wealthy enough to build a custom boat (which is not likely in this lifetime) a lifting dagger board with a bulb would be high on my list.