Excellent comments. Our eyes will indeed deceive us.
My business is manufacturing small optical components for high-end infrared
cameras. While searching for good IR absorbers I came across one article
that included the properties of various materials and paints that contained
a real surprise - for certain paint formulations both white and black were
good IR absorbers.
Because it is too easy to exceed the aircraft structure's glass transition
temperature from solar radiation, it is foolish to use any color other than
white (as recommended by Europa Aircraft) unless there is empirical evidence
to demonstrate that the other than white paint is safe to use.
Best regards,
Rob Housman
A070
-----Original Message-----
Behalf Of irampil@notes.cc.sunysb.edu
Subject: Re: Metallic paint
Unfortunately our eyes are a poor judge of paint when it comes to thermal
absorption.
Remember that almost all thermal energy absorbed from sunlight is from
the infrared range which we can not see. A particular "silver" paint may
look "black" in an infra red image. This may vary by manufacturer and
paint formulation. Therefore even the chart in the construction manual can
be misleading without the specific manufacturer data provided. White paint
seems to uniformly safe, but who knows, is there is one out there that just
loves to absorb IR ;-)
Ira N224XS XS Trike MG
PS Please note my new EMail address!
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