Stability at last

The End of Stability

Work, work, work! No time for blogging until now.

Let's look at a really round bottom boat first.

So first we'll join the chines which leaves us with a trapezoid, and finding the centre of that is described here (centre already marked). If we join the centre of that line with the centre of the curve we essentially have two almost triangles and finding the centre of those is described here.

Once we have the centre of each almost triangle

We can join those centres with a line.

Where that line crosses the line join the center of the curve and the chine line is the centre of the area as both almost triangles are the same size.

We then join the two centres of area and do the math set out here and that gives us the centre of buoyancy

Again if you overlay this hull with the other two the centres of buoyancy are almost the same.

Well what about a boat with no parallel sides. That's even easier than our square boat.

You can divide the underwater area into two triangles and we already know how to find the centers there so I won't go into detail. What is most amazing is that an overlay of this dory type hull onto the other three puts the CB in almost the same place as all the others.

The only thing that is the same about the four hulls is their waterline at the beam. The dory shape is very much smaller displacement although the other three are about the same. I'm going to investigate this further and will comment on it at some later date.

Next time aesthetics or does it look good?