Peter, "Your statement “The speed calculations for a displacement hull are 1.34 times the square root of the waterline length of a hull.” Is not simply wrong, it is technically meaningless.

Your interpretation of a HP hull as planing when running level takes no account of the technical meaning of the term “planing”. "

You are right I should have added 'limited'.

And I looked up Planing and this is what I got.

PLANING - A boat is said to be planing when it is essentially moving over the top of the water rather than through the water.

PLANING HULL - A type of hull shaped to glide easily across the water at high speed.

I don't see how I am misusing the term, but I am prepared to accept that the Proa is a displacement boat that moves through the water, all I want is to know how much hp is required to push it through the water at various speeds.

Thanks in advance,

Talador