Aizawa plans to explore the ships, with a focus on salvaging whatever looks like communications tech to see if theres anything in it that can help with his own radio project.

He picks out something that's probably as big as a large party boat that would not look too out of place in a canon like Star Trek, or like underwater vessels that are properly designed and not likely to implode when it reaches a certain depth.

He's not especially trained, but he's from a world with a tech level comparable to our own.