Hmm:hmm:, I would think, if they had windows then they would have to have lights to help with navigation and I was not aware there were light fixtures that could take that kind of pressure those subs took back then.
Besides, I think they used the sonar for something back then. I think it was to navigate (or see) under water
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As for the Hydrophones, I can't imagine that being useful for anything other then just to listen to the sounds under water