See Martin Simons' Model Aircraft Aerodynamics excellent explanation why a forward CG is the right cure for sailplane tuck under, chapter 12.22:
"The main part of the cause is lack of static margin. brought about by having the centre of gravity too far aft. The centre of gravity should be moved forward to improve static stability and the staniliser rigging angle and/or elevator trim readjusted to restore normal balance." "Another very likely cause is structural flexibility." Thus, if the tail boom flexes, if the pushrods flexes, and thw wingsa and control surfaces flexes, you have to add static stability margin for that, thus even further forward with the CG. Tord ---------- Forwarded Message ---------- Subject: Aerodynamic problem with a Hades Date: Mon, 31 Mar 2003 16:37:01 +0200 From: Tord Eriksson <[EMAIL PROTECTED]> To: "Randy Bullard" <[EMAIL PROTECTED]> Cc: [EMAIL PROTECTED] Hi, If it wants to tuck you have to move the CG forward - maybe you tried the other way? Just a thought, Tord ------------------------------------------------------- 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.
