thanks again for the websites and the pictures these have helped me a lot. you are all right it is a hell of a taper and at scale wing area there is not much of it even at 71" wingspan so it will have to be light. I managed to work the numbers to a 25oz/ft wingloading which is about right for an advanced trainer or so Im led to believe. but after all your advise I think I am better to think a bit simpler and build this plane for a 46 size engine and make it semi scale as kdc suggested. But keep the 71" for another time so its back to the drawing board and calculator I have a spitfull plan and would like to use a similar design just wondering if anyone could tell me what amount of washout is usually used and is it realy needed if the wing loading is 25 or under.