stability: length vs. width

I'm saving all this for future reference. My program does some hydrostatics, but so far I've only really used it to check load capacity vs. draft. I'm going to spend the winter, and possible the whole next year or so, learning how to do more with this CAD program and playing around with different hull shapes. Something someone pointed out to me before, that I thought was interesting, is that, on paper, it looks like giving the sides some flam increases stability, but it will actually put your gunnel under sooner. So I need to play around with different shapes and see what happens at different angles of lean.
On the boat I'm likely to build, more feeboard wouldn't result in a higher CG, but it would affect windage and oarlock position. If I ever design my dream sailboat, I'll have to do more experimenting with freeboard.

 

Living on the Great Plains, I can tell you that, in the real world, freeboard is a huge design consideration - more freeboard will turn your boat into a sail when the wind blows (and it always blows here). But then, with low freeboard, you get splashed a lot (wind = waves, boat breaks waves causing splashes, wind blows splashes into boat). As long as you're moving, freeboard is not an issue; however, when sitting still or traveling at low speed, your boat will be blowing around quite a bit.

If you live in the mountains, you probably don't have much wind to contend with relative to if you lived in eastern CO.

 

What the heck is SOR?

 

That is why I mentioned windage in my last post. I live in Boulder county, which is one of the windiest places on earth. In just the last couple days we've had hurricane force winds. But I do most of my canoeing in Utah. The wind can blow up canyon pretty strong at times and I've had my canoe out on Lake Powel. A sliding (adjustable) seat is a big help because it allows you to trim the boat on the fly. If you are heading into the wind, you trim it a bit bow heavy, if you are headed away from the wind, you trim it more stern heavy. If you are paddling braodside, you find a spot where the boat doesn't want to turn into or away from the wind.

 

SOR = Statement of Requirements

In a formal design or procurement process there is the need at the beginning of the design process to agree on the "requirements" that the vessel needs to meet, which are frequently called the "Statement of Requirements". These may be modified during the design process with the agreement of the affected parties.

Even with an informal design or purchase process for a small boat it's very useful to write down or at least think about the requirements and desires for the boat. This can also be refered to as the SOR.