Luiz,

(by the way, Playstation looks like a beach cat to me - this pushes the displacement speed limit to over 40 knots...)

That is true.


1) The original Catri 26, the US Catri 27 and the Brazilian Catri 27 are the same hull but for cosmetic details. The US 27 has a different **** with longer transom and the Brazilian 27 has a rear seat and increased **** size (at the expense of rear cabin volume). The last is partly due to my request - I like ample ****...


Okay, noted.


2) The rear outrigger foils have a very interesting geometry, that is hard to see in the drawings, but can be seen in the pictures. There is a narrow triangular section under the outriggers supporting the rear foils and locating them slightly under the bottom curve. This feature and their angled down position, enable them to effectively lift the outrigger's transom out of the water - but for the triangular support.


I will look for it in the pictures


3) As can be seen in the drawings, the outrigger itself is inclined forward, relative to the mainhull waterline. When the boat heels, this causes the bow to lift - and the rear foils to enter the water. The modified pitch attitude creates the initial angle of attack.


I guessed as much


>>>The few informations I could get from the designer are that this kind of analysis is plain vanila and wave interaction is the real secret.


Wave interactions ?


>>5) Eliptical x square extremities - the truth is that I have no clue why the designer prefers eliptical shapes both for sails and for foils.


Probably as the result of engineering analyses on the spitfire fighter plane. Eliptical end pieces give a better transition to normal pressures on finite foils. But this approach to wing tip design has often been discarded for other considerations. Long time we had rectangular ending accepting the more pronounced tip vortexes, and currently we have the shark fin trend. I can understand the elliptical shapes for the boards but not for the sails as the reasons for a sqauretop sail or more on teh area of sail control than on efficiency.


>>Anyway, I will learn more about it when the boat is ready...

>>Can't wait

I'll bet Good luck.

Regards,

Wouter