Well, the F18 weight equalizing system may actuall work if it ruled on different mainsails in stead of different jibs and spinnaker area's. The jib is pretty negligiable in the way of heeling moments and yes in that way you have a point Stewart. Going from a 4.15 sq. mtr. jib to a 3.45 sq. mtr. jib doesn't do much at all. It is the same difference as going from a 150 kg double trapping to a 145.3 kg crew double trapping. Who here believes that 4.7 kg difference in crew weight make a significantly difference ?

With respect to the spinnaker; luff length is far more dominant in determining how much power the spi develops then its total area. In the F18 rules both the large and small spis have the same luff lengths. Also the are difference between 21 and 19 sq. mtr is surprisingly small. Only 10 % difference. Basically you take off 10 inches of the leech and you are there. The change in aspect ratio will then only be going from 3.44 to 3.80. So the small spi will have a higher aspect ratio, something that is actually beneficial. Basically is small area will reduce the power a little bit but its higher aspect ratio will go some way in correcting for this by having better efficiency. Both are still small differences in relation to the impact a different luff length can make, but even then these two differences are acting in opposite directions making the net difference smaller still.

With regard to adding lead, that is probably the most influencial equalizer in the system. This seems to be confirmed by real life as all crews try to make the minimal weight where you can just sail with the big rig and added weight. Losing the weight and going for the small sails is not perferred by the racing crews as they almost all feel that the "big rig+weight" is the more performant option.

Wouter