Originally posted by ctsketchIt was a great feat, definitely superhuman. It wasn't a sub in the traditional sense but rather a getaway pod. Something not meant to go deep underwater. I'm not claiming either way, just saying it looked like plastic from the scene.
and whether or not the glass was reinforced or not (which it was because no sub would NOT have reinforced glass in that age and we know Hydra is advanced anyway) it is a very tough feat to be able to break thick glass underwater with a punch
It was a great feat though and IMO Cap's best in both films.