The plexiglass absorb more than 90% of the UV
Hmmmm…interesting. I always thought it was the exact opposite and the Perspex didn’t absorb hardly any UV. Being nicely tanned after a long fliught into the sun sems to bear this out. So – what is it ? Any plastics specialists around here?
If you get a rapid suntan, it probably means that different planes use different plastics, with Socata using some good stuff
However, a google on plexiglass UV absorption shows that almost none gets through. BTW I don’t think planes use Perspex, which is cheap flimsy stuff which cracks very easily.
@Peter, that may well be true, I’m referring to Cessnas. Btw, Perspex is widely used as a generic term for GA windshields here.
I googles it also but found some vastly divergent answers.
This inspired me to check the exact composition of mine. A four layer laminate of stretched acrylic-vinyl-vinyl-stretched acrylic.
Generally light aircraft canopies are acrylic, for which the trade name Perspex or Plexiglass is often used depending on market. This has the advantage of being highly sunlight resistant over decades, as well as being amenable to scratch removal with abrasives and re-polishing. The downside is that it’s very brittle compared to Polycarbonate (Lexan) which unfortunately doesn’t share the other advantages of Acrylic.