Sub Vs Sub

just wondering about the way sub vs sub action goes, given i played the escort an convoy vs 3 subs, i used the ign ix, now the standard for this is the corvette. and thats how the subs seem to be acting .like i was an corvette. even to the point where they would just sit there around 100 or so mters facing the same way, if i go down they come up. i just sit at 90 dgr angle and plugem in the side .but not once was there any change to the depth of thier torp fire. now given we can fire as deep as 50m . will they do the same and if we design an mission form the start as an subs vs sub. would thier tatics change. ie attack from depth of say 20 to 40 meters ? this would also be an more greater risk for boat drivers.

The AI haven't been changed, so they will not fire at the deeper depths.