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<DIV><STRONG><FONT size=2>The best rule of thumb to use for adequate cooling
inside a cowled ingine is if you are truly moving the air over the hot parts of
the engine the exit opening should be twice the squares of the
intakes.</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2></FONT></STRONG> </DIV>
<DIV><STRONG><FONT size=2> Del K.
Rykert<BR> AMA - 8928 <BR> NSRCA
- 473<BR> Kb2joi - General </FONT></STRONG></DIV>
<DIV> </DIV>
<DIV><STRONG><FONT size=2></FONT></STRONG> </DIV>
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style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=aquennoz@ipa.net href="mailto:aquennoz@ipa.net">Adam Quennoz</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=discussion@nsrca.org
href="mailto:discussion@nsrca.org">Pattern List</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Tuesday, February 04, 2003 5:34
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Thoughts about air scoops.</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>It seems the trend these days are air
scoops. Before a scoop is effective, the area of the air exit must
equal or exceed that of the air intake thus allowing a positve air flow to
occur. With all the scoops people are putting on the nose of the
aircraft, there must be a pretty good sized hole somewhere for the air to
escape. There are cheek scoops, chin scoops and now with the concern of
cooling the crank cases, there are scoops above the engine compartment.
I call them "nose scoops". </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Has anyone thought of making EXITS on
the top of the nose above the engine, and/or exits on the cheeks?
Basically put the scoops on backwards. The air flowing over the
backward facing scoop would actually create lower pressure inside the engine
compartment allowing a larger volume of air to enter the chin
scoop. The air entering the chin scoop can flow all around the engine as
it makes way to the exits of the engine compartment, and what's
left can flow down the pipe tunnel. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I'd like to hear what others have to say
about this idea. I'm thinking of trying it on my pattern
plane.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Regards,<BR>Adam Quennoz<BR>AMA 383866<BR>IMAC
2439<BR>NSRCA 3546<BR></FONT></DIV></BLOCKQUOTE></BODY></HTML>