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"Increase in resistance at transitional speeds between displacement and planing. You know, around where speed in knots over square root of LWL in feet is about 1.5."

T

he number didn't mean much to me, but it was easy to imagine that a long, light, narrow hull would transition gracefully from displacement to planing without making a big fuss. "With our narrow hull, we don't need much ballast for self-righting, and if we don't need much ballast, it's easier to make the keel retractable, so the keel can be, like, a really deep draft bulb." "I'm with you so far," I said as I watched Lee draw a keel even deeper over what I thought was already an absurdly deep one on the plans. "Then just add the ballast pods — small water ballast tanks out on struts on either side. They fold up for docking

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and post-race raft-ups, but they would make the boat seriously fast." She sketched in the struts and pods, making them long enough to project the water ballast out m u c h farther than any c a n t ing keel c o u l d hope to r e a c h with its bulb. "This way you can keep the keel vertical so it can work efficiently, you don't need any complicated canting mechanism, you don’t need power to drive the keel hydraulics, and you don't need one of those front rudders or extra daggerboards to make up for an inefficient

Above, water ballast in use on an upwind leg and, left, retracted for going downwind.

canting keel." "I have to agree that a front rudder is about the last thing I'd want on a cruising boat," said the foredeck crew. "Just one problem," added the old shipwright. "Your newfangled ballast pod cruiser-racer won't self-right with those pods in place. It'll be as bad as a trimaran if it goes ass-over-teakettle." "No biggie," assured Lee. "The ballast

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Latitude 38 July 2007  

The July 2007 issue of the West's premier sailing and marine magazine.

Latitude 38 July 2007  

The July 2007 issue of the West's premier sailing and marine magazine.