Fall of the Rising Sun Ultimate is working on such an addition as we "speak", with multiple Japanese submarine models. It is unknown at this time how "accurate" they will be attacking, if we even add the AI_Torpedo stuff to them. There is no timetable, and it may never happen, just to balance any anticipation...
jhapprich has a mod in the downloads section relatively easy to find:
http://www.subsim.com/radioroom/down...o=file&id=5205
There are a couple of other AI_Sub mods out there with torpedoes, but I'm not sure which ones are actually functional, or relatively accurate, or if they are even available anymore. Some one else will have to address that...