In a recent (and unpopular) uboat movie that shall remain nameless, there is a scene on the American S-33 where someone asks "how deep will she go?" to which the Chief of the boat replies: "Oh she'll go all the way to the bottom! But we like to keep it above 150 feet otherwise the bilge pumps cant keep up." All the while water seemed to be leaking in everywhere. I'm sure the modern subs are much better but did the old subs really leak that bad? I myself am pretty comfortable with the idea of traveling on a submerged sub, but one that leaked that bad would make me change my mind in a hurry!