<<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>>
         <<  Lancair Builders' Mail List  >>
         <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>>

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

LML website:   http://www.olsusa.com/Users/Mkaye/maillist.html