Quick question - spying w subs

So I'm at a critical juncture in a game where an opponent is going to win via neptunium unless my heavily laden sub armed with navigator, infiltrator, helmsman can take over his mine.
I have the sub actually aiming for a different spot but it will pass close by the mine. I was kind of assuming the sub can see a little bit around it, like a base's defenses, but now I'm not so sure...... The original plan was to get close and swoop in if my force can overcome the defenses.
What can subs see in enemy territory?
I guess the point is moot because either the sub successfully wins the fight and we get some time, or it doesn't and we lose. I'm still curious what to expect.
I have the sub actually aiming for a different spot but it will pass close by the mine. I was kind of assuming the sub can see a little bit around it, like a base's defenses, but now I'm not so sure...... The original plan was to get close and swoop in if my force can overcome the defenses.
What can subs see in enemy territory?
I guess the point is moot because either the sub successfully wins the fight and we get some time, or it doesn't and we lose. I'm still curious what to expect.