>>Does anyone care to guess at why some more modern designs (Ventus 3, JS-3) >>have several stages of wing kink while some older designs (ASG29, Diana 2) >>don't?
I believe that a semi-elliptical planform is the best for a wing with probably a hyperbolic "dihedral" or elevation. With the level of manufacturing/mould-making ability extant in most sailplane work, the cheapest option is to go for several unaesthetic and reportedly speed robbing kinks in the leading edge. If there was more money involved, I don't think these kinks would exist and the leading edge would be a smooth transition from root to winglet. It might be easier to finish profile a segmented wing versus a continually variable wing.. until someone invests in a robotic finisher capable of doing an accurate profile over the full span. Oddly, in surfboard manufacturing, they have had to go to a technology like this to keep the labour costs reasonable but now so many people have the machines that the cost of shaping per board is almost not enough to pay for the machines. The machines are not that expensive either, especially when you consider it takes 250 hours to finish profile a sailplane wing. That is in a factory which actually finish profiles wings as opposed to sending them out for the customer to do after the warranty period is over. D _______________________________________________ Aus-soaring mailing list [email protected] http://lists.base64.com.au/listinfo/aus-soaring
