From: Fredmoreno@aol.com
Message-ID: <1378653f.2521b137@aol.com>
Date: Tue, 28 Sep 1999 01:50:47 EDT
Subject: OAT and solar heating
To: lancair.list@olsusa.com
Mime-Version: 1.0

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The effect of sunlight on a temperature probe is negligible once the plane is 
flying, as long as the probe is exposed to the air stream and not behind a 
window.  The convective heat transfer rates from the air stream are hugely 
greater than solar radiation input, even if the probe is painted flat black.  
On the ground, however, it is a different story, as we all know.  So put the 
sensor in the shade if you want to know OAT before engine start.  If it is in 
the sunlight, keep it in the propeller slip stream if you want a good reading 
while taxiing out to the runway, recognizing it may take a few minutes for a 
hot sensor to cool to ambient temperature in the propeller breeze.  

Fred
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