They have upward-looking cameras, at least on some of them. You can see it in the last Smarter Every Day video[1] where they're talking about surfacing a subma

They have upward-looking cameras, at least on some of them. You can see it in the last Smarter Every Day video[1] where they're talking about surfacing a submarine in the arctic ocean. At several points you can see a video monitor showing an upward view of the ice. [1] https://youtu.be/XFJnWp1tAdU?t=1427 https://youtu.be/XFJnWp1tAdU?t=1427 e: to be clear, that upward looking camera isn't going to be enough to detect much beyond your own footprint. If someone is about to cross that area you'd need some other way of detecting them.