Rhino,

Saving weight will indeed always be a trade-off with losing stiffness. But it can be won back at other places as well.

My mainbeam is about 3.8 kg as a bare tube and yes I would welcome a little more stiffness. Because my mainbeam is so light I need more then 15 mm of prebend to keep it under a nice load situation while sailing. But I admit, as I wrote earlier, that the F18 beams are much heavier and stiffer, I don't really expect them to go past 15 mm of prebend. So in the F18 case it is not a really serious issue. I think the optimimal point is somewhere halveway.

By sailing my own boat I found that platform stiffness is not a very large component in the way of performance. And lots of stiffness is often lost in the beamlanding design and other places.

As an engineer I look at the rule sets from a designers point of view. Freedom allowed under them is in my opinion more often used to arrive at simpler or more elegant solutions then for performance gains. Limiting the designers freedom in this can eventually became a drawback for a class. But I admit that this view may well be subject to disagreement.

Anyway, I'm out of time on this topic. I have to complete another design assigment. (Why do I always slack on these till it is almost too late to finish them in time ?)

Wouter