We are guessing (gut feeling) our way into errornous conclusions again.

There is no reason why they F16 designs "can handle the additional weight" of the Viper. My own Taipan F16 (homebuild) is 121 kg in sloop mode. How much difference can a few additional kilograms make ? The first Stealths were not close to minimum weight either and that didn't hold them back.

The reason why the FX_one is hard to right has alot more to do with the fact that the FX-one mast section is heavier then the F16 mast sections. Not so much with the weight of the platform. Yes, 250 grams difference per meter already results in a 9 kg righting weigth difference. Compare that to a 10 kg difference in the hulls only accounting for 1.84 kg difference in righting weight when the mast tip just clears the water surface. A factor 5 difference !

If the Viper F16 is 20 kg heavier then minimum weight and weigths ready-to-sail in SLOOP mode 127 kg and all the additional weight (20kg) is located around the hulls, then it will take only 3.7 kg more weight on the righting line to recover it from a capsize when compared to a minimum weight F16. The case with the FX-one (that does have 35 kg hulls compared to 23 kg F16 hulls) requires then 11.2 additional kilogram in body mass while righting. A number confirmed by personal experience.

There is not much difference between the Viper and "normal" F16's at all. Apart from the weight felt when lifting the boat and maybe some top line speed. There is certainly very little difference in righting weigths unless a carbon mnast is used on the "normal" F16's

Wouter