I just joined this forum because I am interested in a Kitfox 3 on floats, but concerned about its useful load. Can someone explain what makes the Kitfox 4 have a higher gross than the 3 - and is it possible to increase the useful load of the 3 somehow? I have been told that the 3 can carry significantly more than its legal maximum gross, but I prefer to stay legal. So what is it that limits the max gross of the version 3. I have also been told that the gross can be increase by 20% if the airplane is on floats. Is this correct, and why?