Join Date: Sep 2008
Location: Victoria B.C. Canada
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Re: Modern Hull forms and Motion Comfort
I think most agree that boats should be compared by displacement rather than length. If we compare 2 designs of the same displacement, one an older design and one much newer, the comparisons are interesting.
The Westsail 32 is part of this thread so it can be the older design. For a newer design one of my favorites and one that Bob is very familiar with as it is his design, the Saga 43.
Westsail 32 Disp 19,500 lbs
Waterline 27.5 ft
Hull speed 7 (1.34 x sq rt waterline)
34% ballast ratio
1064 lbs/inch immersion
Saga 43 Disp 19,843
Waterline 39 ft
Hull speed 8.7
39% ballast ratio
1634 lbs/inch immersion
The Saga can carry about 1.5 times as much weight before it is 1" lower in the water than the Westsail. It sails faster and gains all that 11 feet of boat and more than that in increased waterline length allows.
I know which one I would sooner cruise in.
Living aboard in Victoria Harbour