Why is sound rendered outside your plane once your cockpit is closed?
Because glass doesnt fully stop sound. It will dampen it though.
Even with all of my windows closed, I can still hear cars drive by my house.
I don’t mind hearing sounds like other planes, but it’s really stupid you can fly a jet with mach 1 over a battlefield and locate a tank because of the idle engine sound.
Try it with your house travelling at 400 mph thru the air.
Oh and, with an un-muffled generator sitting in your lap.
And and, while you are wearing headphones so you don’t go deaf from the above two.