Blended Winglets: - this subject was discussed before, and here is the link for you hope it will answer your question. It is a very interesting subject.
http://www.pprune.org/ubb/NonCGI/For.../001327-2.html The link is to page 2 Have a look at page one
[This message has been edited by Royan (edited 08 April 2001).]