Quote:
Originally Posted by sailaway21
To overhangs themselves the author's state:
A large forward overhang is likely to increase pitching, since large pitching moments are created when a wave hits this part of the hull far from the center of gravity. Aft overhangs may, of course, have a similar effect in following seas, but the frequency of encounter is then much lower so the problem is small. On the contrary, the stern overhang may be beneficial since it may damp the pitching motion in head seas. A high freeboard forward, and a flared one in particular, prevents green water on deck, and spray hitting the cockpit is effectively avoided also. The hull thus gets much dryer......
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While I understand the comment that "overhang will increase pitching"; I can't say I agree. If the
same boat were built with a plumb bow the pitching moment due to bouyant force would be equidistant from the CG. Now if you shorten the boat's hull down to the LWL you are going to reduce pitching moment; but now you also have a much smaller boat; and a much different hull form. How do you achieve a high forward freeboard; with flare, and little overhang? Seems like you would have one strange looking bow; but that's just my way of thinking
Quote:
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....Most modern designers strive for small gyradii, a light hull, large stability and a small keel. All these features tend to increase the accellerations on board the yacht, thus making it less seakind. For a cruising yacht this is unlikely to be the optimum solution.
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This is what I was trying to point out earlier; many of the hull design factors that would make a racer quicker on the race course are the same that will make a boat less seakind/stable. That's why it is possible that many of the new era racer/cruisers are less well suited to cruising than they are for racing. That's fine if you want a fast boat that will pound your guts out but you'll finish ahead of the fleet; but that same boat might be dangerously fatuiging on an offshore passage.
In regards to the issue of LOA having a negative effect on MCR; well that is only true if you increase the LOA (and LWL) without an increase in displacement. Meaning, if the weight per unit length is reduced the boat will have a lower motion comfort (the chop and waves will have more effect on the motion of the boat). If that is not true I would like to see some data or calculation that disproves it.