Rob, That's an interesting page. I especially like the drag summary at the bottom. For a mid Cl the airfoil is responsible for 55% of the drag, induced drag is another 20%, the fuselage is about 18%, the linkages about 3% and the stab is worth about 4%.
In almost all cases the linkages on the bottom were a better choice. In all cases faired were the best (other than internal) and the shorter the linkage (and fairing) the better. No wonder everyone puts so much into the wing. Worth about 75% of the overall drag at average flight speeds. JE -- Erickson Architects John R. Erickson, AIA > From: [EMAIL PROTECTED] > Date: Tue, 21 Jun 2005 19:16:51 EDT > To: [email protected] > Cc: [EMAIL PROTECTED] > Subject: [RCSE] Re: top or bottom driven ? > > I like bottom driven flaps and ailerons for various reasons. According to > Dr. Hepperle a properly faired set of 4 linkages on the bottom of a wing add > around 3% total drag to a typical F3B airframe. You can go dig around his > website and find a number of interesting tidbits. > _http://www.mh-aerotools.de/airfoils/index.htm_ > (http://www.mh-aerotools.de/airfoils/index.htm) > > happy trails - Rob Glover > > > > > > hi all, > I've been asked this a few times, and I give my opinion, > but i want to see what you guys have to say. > > What gets better mechanical advantage, top or bottom > driven linkage, and how much does the drag of bottom driven > really effect things, if any ? > > My vote goes towards bottom driven. > I can always get the throws I want, easy to set up and adjust, > and gives a solid control surface. > > Dave Hauch > www.git-r-built.com > > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and > "unsubscribe" requests to [EMAIL PROTECTED] Please note that > subscribe and unsubscribe messages must be sent in text only format with MIME > turned off. Email sent from web based email such as Hotmail and AOL are > generally NOT in text format RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
