Why do older planes have large bracings on front windscreen. It is a material strength issue?
It was cheaper and simpler to do it that way, and overcoming optical distortion with curved surfaces was a major issue, especially for the late-blooming PLA. New manufacturing techniques were required to solve issues related to heat treating and cooling curved glass without warping it, mold surface imperfections, tighter tolerances etc.
In this J-10 documentary, the team talk about how they almost imported bubble canopies but opted to r&d and produce a domestic solution
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