Not buying it. It all sounds good til you consider looking at it from another angle. The boat with overhangs has a progressive, building dampening effect from reserve buoyancy. So, as it hits a wave, the force isn't all at once, but as the bow digs deeper into the wave, more of the reserve is tapped, thus dampening the impact gradually. The plumb bow has less impact with a wave, but also lacks buoyancy, so it will tend to plow. The broader overhanging bow looks like the clear loser in the drag comparison, but plowing drains speed too.
As the wave moves back along the hull, the bow will pitch up as the center of buoyancy is encountered, but a boat with overhangs will, while lifting the bow, also utilize the damping effects of an overhanging stern. In other words, the stern will settle or squat some as the lever arm moves back. So, as a consequence, as the hull lifts at the bow, it settles at the stern, smoothly with progressive resistance. This also limits the height the bow rises as the wave moves back. While the angle of motion is a given amount, the total deviation from center is divided between the bow and the stern. A plumb bow and stern, cannot do this nearly as well. As the lever arm moves back on a plumb bow, the wider (and typically flatter) higher buoyancy stern exerts all it's resistance at once. Ever leveraged something that was loose on one end (the bow) and rigid on the other (the plumb stern)? Since the stern is so much more buoyant from the outset, it doesn't settle into the water as the lever arm moves back. As a result, the stern acts like a
hinge point on the water. As the wave moves back, the exerted leverage of the wave on the higher buoyancy stern, forces the bow to lift higher as a result, then fall further as the wave moves past the center of buoyancy. More of the angle of pitch is at the bow, with little at the stern. The sharp, low resistance plumb bow then slices deeper into the next wave perhaps submarining as the non-compliant stern rides over the wave and leverages the bow down hard. Having insufficient buoyancy to counter the stern, it plows even more. This begs the question. Since the wave moving past the hull is essentially a constant, why would you eliminate or reduce reserve buoyancy in the bow and have an excess in the stern? Great for racing. The fine, plumb bow slices cleanly through the water, and the high buoyancy stern keeps the boat up on the bow wave. I can see where Jeff's champion would be better for max speed in reasonably calm conditions, but toss and tumble? Forget it. I'll stick with some overhangs. Having been on one of these plumb bow/stern jobs recently in some gusty/slightly beyond choppy conditions, and feeling like I was going to be slingshot from the cockpit due to the pitching motion, I can say she was fast (all sorts of zippy in the initial calm, but not fast enough (to outrun the weather when things got more interesting....and it really wasn't that bad weather-wise), and not comfortable at all, because at the trough of each wave it was BANG, BANG, BANG, and it got a little damp too.
Thoroughbreds are beautiful and fast, but I'll stick with my Quarter Horse any day.
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