Mike,
And there is more to this story. Being based in Manningtree, I can go out for a sail around HW, and if I stay away from the channel below Mistley, I will never have much more than 2m depth (and at times, and in some places, quite a lot less). My strategy is to lower the keels only partially, on the basis that some additional leeway is better than going aground. On the water this morning I got to thinking… The keels are there for both ballast and leeway control. So, in a light to medium breeze, given that there are two keels, and that the depth is adjustable independently, how much would we expect leeway to increase if one or both of the keels are raised (i.e. by a third or by two thirds)? Would there be some way to test this using a chart plotter?
Jim