>I am sure someone with more knowledge about fluid dynamics can say this >better than I can, but it is NOT frontal area that determines drag. The drag >increases faster than the frontal area when you lower the flaps and the drag >increase from 60 degrees and 90 degrees is enormous, much more than the >frontal area increase. > >Anker
True. Im no aero dynamicist either, and certainly downward deflection of airflow at partially-deployed flaps reduces effective breaking. -- The main issue for me is that flap deflection between 75 and 90 degrees adds only 4 percent more frontal area. To me the extra strain required on servo, linkage, and hinge is not worth the last 15 degrees of deflection. Dieter http://shredair.com RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]