This has been discussed on RAC in the past. There was an article in Soaring back in 1975 that discussed the subject. This link covers some of the basic points.
(http://www.soaridaho.com/Schreder/Co...olor_Temp.html)




"Bret" wrote in message ...
I always thought sailplanes were white so the interior structure
wouldn't overheat and approach the glass temperature of epoxy, about
190 F, and fail. And yet I see homebuilt aircraft of wood/epoxy
structure painted all colors. So is it the gelcoat that the white
color is protecting?

Here is an article from the