I ran into one of those--litterally. Just drove right into the middle of one in a storm. Thought it was just a gaggle of Destroyers at first until I caught sight of Moby Dick here...
Then I saw red and went to flank, damn the torpedoes (or, rather, the depth charges) and tried to bag him, but he was doing something North of 18 Kts and I had no chance. I think I also died. I probably died. But it was pretty neat there for about twenty minutes.