Quote:
Originally Posted by sailaway21
Regarding ships, which do not ride the same as sailboats, Jeff's logic would be completely backwards. The plumb bow is not seen on ocean going vessels for just the original reason Plumper pointed out, the tendency to bury the bow, loading tons of water on the foredeck.
If you examine ships of the early twentieth century you'll see that their plumb bow had very little flare and this was their death knell design wise. When you start burying the bow of a ship you're going to encounter structural damage sooner than later.
I too am somewhat sceptical of the current plumb bow on sailboats if only for the wet ride. That they do not bury their bows
more than they do I'd ascribe to the fact that they do not carry their fineness of entry very far aft and that they're relatively small in proportion to wavelength. Like many, the aesthetics leave me ambivalent. (g)
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The reason we see plumb bows on new sailboats is the same reason that CCA boats had short LWL's. Racing design rules. Since LOA is now the main design factor it makes little sense to reduce the LWL except maybe for very light air to keep the hull's wetted surface minimized. But with the shift (for performance reasons) to light displacement and bulb keels; the longer LWL helps these boats get on a plane when sailing downwind; therefore they make it as long as possible.
In terms of sailing characteristics; the long overhangs (which usually also equates to heavier displacement) will always have better motion comfort. New boats carry so little draft that the first 5-6 feet of the hull at the bow may only be 4-6" deep. When they go over waves they tend to slap that first few feet onto the next wave rather than knife the bow through it. It might be fine for short distance racing but if you are going for an extended offshore cruise or race I think it would become very tiresome. Lighter displacement of the hull also equates to more tendency to pound (the wave will transmit more acceleration force to the hull due to the boat having less inertia).
I can't say I agree with the blanket statement that a CCA era hulls are not offshore capable. The "International Offshore Rule" hulls were designed to be "offshore" boats but we all know that there are major issues with many of those designs also (IOR is AKA the "broach coach" of hull designs). I think it depends on the particular IOR or CCA hull.
There are lots of Pearsons, Allbergs, Newports, etc. sailing on SF Bay and beyond (in addition to even older fleets that are still racing like Birds, Knarrs, Folkboats, Int. One Design). Some days the winds are 30-40kts in the slot; and these old boats are racing with the crew hiked out and the lee deck buried up to the doghouse. (Yeah; they are probably not sailing them optimally, but it sure is fun to watch a lapstrake hull Folkboat sail at 60deg heel).