Builders' Forum Archives
Re: Chester Yawl Conversi
Posted by John R. Pollard on Jan 7, 2007
Elaborating further on Laszlo's comments, if you were to add a sail rig to the yawl, you would definitely need a lateral plane of some kind in order to sail upwind. The usual way to achieve this is with a daggerboard. A centerboard or leeboard(s) would work too, but they're more complicated to design and more difiicult to build.
In a boat of this size, I don't think you'd want to add any fixed ballast. This would only add weight to what is supposed to be a nice light boat. And it would alter the designer's calculations for reserve bouyancy and floatation in the event of swamping/capsizing -- probably not something with which you should fiddle too much.
Fortunately you shouldn't have to resort to this: The occupants of small boats serve as a better form of ballast than anything you could install, since they can shift their weight to the best position for countering the forces of the sailrig.
I had ventured that perhaps the yawl lacked sufficient form stability for comfortable sailing. CLC countered that the yawl behaved very well as a small sailboat. Not having sailed it, I defer. But one of the characteristics I look for in small sailboats is abundant static form stability: I like a boat I can stand up and walk around in when the spars and sails are rigged without worrying that a misplaced step will send me for a swim.
Our CLC PassageMaker Dinghy meets this requirement in spades (even without the daggerboard inserted). True, the design qualities that achieve this kind of form stability in small unballasted sailboats (a low length-to-beam ratio and a wide flat bottom) are not the same as those that achieve optimal sailing (much less rowing) performance, but I'm somewhat decrepit and prefer to swim only by choice (unlike the Yawl's designer, who is apt to swim from his creations in any harbor at any time of year). In other words, I'm willing to sacrifice a bit of sailing performance for a the added safety of stability. So, if you plan to do a lot of sailing, I cannot commend the PMD enough.
Hey, look what else I found in my archives (it appears 56 sq. ft. of sail is the ticket):
In Response to: Re: Chester Yawl Conversi by Laszlo on Jan 7, 2007