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post #10 of Old 10-20-2007
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Sailhog, plumb bows are difficult to get right for the cruising boat, in part because they "work" or don't work in a tighter band then swept bows. This means if you overload or badly trim up a boat with plumb bows, it is going to be an uncomfortable and possibly dangerous ride.

At issues is usually downwind performance. Plumb bows tend to dig in and pig-root around int he wave, meaning that the helm has to perform exagerated and frantic corrections...that sometimes don't work and the wave runs away with the bows and the boat broaches.
even when it is not broaching, it makes for an uncomfortable "swirly" ride with an extra twist to the boat motion as the bows bite and get scewed sideways for a little bit of every wave.

There are good solutions to this available...but they are not bog standard for production boats that are basically floating caravans.
My favourite simple solution is to sweep the below-water-line hull upwards to the plumb bows so that the bow is sharp, and vertical...but not very deep. The boat can thus carve into and through waves when going up wind, and sit back a little and get its nose out of the waves entirely when going downwind. No more biting in and pig-rooting around....But it takes a lot more engineering and design know-how and it all goes for nothing on the day that some new owner decides to mount 120kg of 'something" shiny and nifty in the bows.

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