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<DIV><SPAN class=240415422-29052006><FONT face=Arial size=2>>> Also,
the wing and stab area should include the ailerons and elevators,
respectively.</FONT></SPAN></DIV>
<DIV><SPAN class=240415422-29052006><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=240415422-29052006><FONT face=Arial color=#0000ff size=2>When
calculating wing/stab area, are you also including the area occupied by the
fuselage? Such that an 18" wing root on a 6" wide body would add 108 sq
in to the panel area. </FONT></SPAN></DIV>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B>
nsrca-discussion-bounces@lists.nsrca.org
[mailto:nsrca-discussion-bounces@lists.nsrca.org]<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>
<DIV>
<DIV>On May 29, 2006, at 4:40 PM, Nat Penton wrote:</DIV><BR
class=Apple-interchange-newline>
<BLOCKQUOTE type="cite">
<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>
<DIV><FONT face=Arial size=2></FONT></DIV>
<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>
<DIV><FONT face=Arial size=2></FONT></DIV>
<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>
<DIV><FONT face=Arial size=2></FONT></DIV>
<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>
<DIV><FONT face=Arial color=#0000ff size=2></FONT><BR
class=khtml-block-placeholder></DIV>
<DIV><SPAN class=Apple-tab-span style="WHITE-SPACE: pre"></SPAN>CG (from LE
MAC) = MAC/6 + 0.25x (As/Aw) M</DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT><BR
class=khtml-block-placeholder></DIV>
<DIV>Also, the wing and stab area should include the ailerons and elevators,
respectively.</DIV>
<DIV><BR class=khtml-block-placeholder></DIV>
<DIV><BR class=khtml-block-placeholder></DIV>
<DIV>Ron Van Putte</DIV>
<DIV><BR class=khtml-block-placeholder></DIV></BLOCKQUOTE></BODY></HTML>