Senior Moment Member
Join Date: Jun 2011
Location: West Vancouver B.C.
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Most of us think about twin keel as an advantage to moor in low tides scenarios. In the market there very interesting twin keel available, and my question is how these boats perform in severe weather, comparing with fin keels?
When the boat heels there is one of the keels that is further down than the other. Does the opposite one which is upwards helps to trim the boat to help the boat navigate more comfortable?
My first boat was a British bilge keeler called a Vivacity 20. It was far from fast but it was as stiff as a church. I had no basis for comparison until I went out on a Cal 20 - I couldn't believe how tender it felt compared to my twin fin.
I guess they act a little bit like the modern canting keels - as the boat heels, it is trying to lift the weather keel (and 1/2 the ballast) up and out of the water. Also, if the twin keels are canted somewhat, say 15 degrees, as the boat heels, the leeward keel becomes more vertical and theoretically should resist leeway better than a single centerline keel.
I've long wished a good designer like Mr. P would do his magic on this concept to see where it could go re: performance. There are a number of potential advantages but the increased wetted surface always seems to put people off the idea. They are popular in Europe because they can dry out without legs but the concept is usually seen on pretty tubby boats, not on anything with any performance illusions.
I, myself, personally intend to continue being outspoken and opinionated, intolerant of all fanatics, fools and ignoramuses, deeply suspicious of all those who have "found the answer" and on my bad days, downright rude.