>>531232496
it's polycarbonate
with a normal framed canopy you can make things a lot easier by just putting a slab of something heat/bird resistant on the front and then using much thinner material everywhere else for less weight and visual distortion, but going frameless the whole thing has to be able to survive coming out of the mold intact (actually kinda hard) plus heating (limiting factor on F-16 low alt speed at least was and afaik still is not melting the canopy)/birdstrikes/gforces while still being thin enough for good visibility and not blowing out the weight
you CAN solve most of these issues (except manufacturing pain and weight) by just making the fucker thicker, but then you get tons of distortion through the polycarbonate and it looks like ass