Originally Posted by Seeker
Matt so are you saying the Falcon rudder blades are thicker in section but narrower from front to back? And if so, does that mean you made them slightly longer to make up for the lost area?


Foil thickness is expressed as a percentage of the chord length. i.e in a 10% foil, a 190mm fore and aft measurement will result in a maximum thickness of 19mm. Where that thickness occurs is dependent on the foil section chosen. There are a variety of foil section theories so I will not even get into that.

I have tried to keep fairly close to a certain surface area on the foil sections. There is definitely a higher aspect on the new Falcon rudders, but the driver in the shape change was to provide some other features than just a higher aspect foil. The latest trends in the A class and you can see this on the C as well, is to go to an extreme aspect ratio. Some of the A class rudders I have seen are down to 75mm in chord. This is for that whole reduced drag kick. The problem with this is that you have to keep water moving over them to keep flow attached. Sporadic control movements, pinching and parking on the line really become an issue. This kind of follows my view of the curved foils. There is a potential for a small performance edge in certain conditions, but the skill level required to drive the boat to that point becomes an order of magnitude higher. The top guys are going to make any platform work and will win races. To me a great design is one that the average guy can get on and be able to drive to its numbers over the whole range of conditions.