http://www.rickwill.bigpondhosting.com/Prop_Strut.JPG"

The prop mounting and fairing was worse than I imagined. You went to all that work and effort to fair the hull and then threw much of the effort away.

"Shaft - Rotates to drive a prop and follows a circular arc."

You know that the rotation creates drag too? Not just the form shape drag.

"Surface Piercing Appendage - Sail rocket lateral restraint:

It is the white appendage on the windward side aft of midship.  Visible from the overhead shot and over Paul's shoulder between 30 and 35 seconds in then later when he is cracking along beside the beach.  You could always believe that he would be faster with the appendage under the hull but you would be wrong."

I point out the hard chines create separation and drag and you point to a hundred knot hydrofoil that uses hard chines to get the hull out of the water as justification for your displacement boats use of hard chines.

I point out that appendages penetrating the surface cause unnecessary drag and you point to a 65 knot proa.  But please don't take my word for it, lets see what the designer has to say about that appendage.

 

Your appendage drag is truly horrible too, but for some reason I don't think you have the power to overcome the drag like the Vesta's Rocket does.

I need to add that at your target SLR of 1 to 1.3, the extra drag of the hard chines, extra wetted area, concave aft hull, non aerodynamic appendages projecting into the water, etc. probably don't add up to much, they may not even be measurable. It is only when you get past displacement boat speeds that they matter and for what you are trying to do I would think that aiming at a SLR of 1 is the way to go. You are right, nothing I have suggested would be of any value to you.

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