I have hit a T2 beforeabout 2m under the keel, and it worked perfectly. I even saw a few life boats fly off in random directions!!!
I don't remember what mission it was, but I started one with a XXI and shot a T2 torpedo at an Illustrious Carrier and it sunk in less than 40 seconds! That doesn't seem right. (I also had the slow sinking option enabled)
Anyone know what happened? I didn't even target a room!