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<DIV>Ron, I would like to see your rendition, if you can share it, or tell me where I can find it, if in the public domain. It will be interesting to compare. </DIV>
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<DIV>Thanks</DIV>
<DIV>Matt</DIV>
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<DIV>In a message dated 5/29/2006 8:03:41 PM Eastern Standard Time, vanputte@cox.net writes:</DIV>
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<DIV>In my calculations I do include the area occupied by the fuselage. I assume the calculation by Nat does as well, but I don't speak for him.</DIV>
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<DIV>Ron Van Putte<BR>
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<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma size=2>-----Original Message-----<BR><B>From:</B> nsrca-discussion-bounces@lists.nsrca.org [<A title=mailto:nsrca-discussion-bounces@lists.nsrca.org href="mailto:nsrca-discussion-bounces@lists.nsrca.org">mailto:nsrca-discussion-bounces@lists.nsrca.org</A>]<B>On Behalf Of </B>Ron Van Putte<BR><B>Sent:</B> Monday, May 29, 2006 6:07 PM<BR><B>To:</B> NSRCA Mailing List<BR><B>Subject:</B> Re: [NSRCA-discussion] CG<BR><BR></FONT></DIV><BR>
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<DIV>On May 29, 2006, at 4:40 PM, Nat Penton wrote:</DIV><BR class=Apple-interchange-newline>
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<DIV><FONT face=Arial size=2>The following formula was presented by noted British modeller Gordon Whitehead in How To Make Scale Models Fly ( 1980 ??). I have been using it over 20 years and find it dead on for pattern:</FONT></DIV>
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<DIV><FONT face=Arial size=2>CG (from LE MAC) = MAC/6 + 0.25x As/Aw M</FONT></DIV>
<DIV><FONT face=Arial size=2>As - area stab Aw - area wing</FONT></DIV>
<DIV><FONT face=Arial size=2>M - moment arm, ac to ac</FONT></DIV>
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<DIV><FONT face=Arial size=2>It is easy to use the graphic method to find the wing MAC. You can guess at the stab MAC and be close enough.</FONT></DIV>
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<DIV><FONT face=Arial size=2>The formula works on anything from a tailess to a Quickie.</FONT></DIV></BLOCKQUOTE><BR></DIV>
<DIV>Nat - I haven't compared the formula with the one I developed more than 40 years ago, but I think yours would be better understood if you use some parentheses:</DIV>
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<DIV><SPAN class=Apple-tab-span style="WHITE-SPACE: pre"></SPAN>CG (from LE MAC) = MAC/6 + 0.25x (As/Aw) M</DIV>
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<DIV>Also, the wing and stab area should include the ailerons and elevators, respectively.</DIV>
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<DIV>Ron Van Putte</DIV></BLOCKQUOTE></BLOCKQUOTE></DIV></BLOCKQUOTE></DIV>
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