163776
Nah, you sneak upto a hostile attack submarine untill you're close enough, and then begin charging it all ahead flanks and active sonars banging away, causing the enemy sub to tactily shit itself and fire a barrage of torps in your direction.
You then simply evade the torps with the help of your totally not unfair and unrealistic 3D camera, and get the torps to follow you in the direction of the hostile sub.
Once you get close enough, simply form a knuckle towards the enemy sub and run towards the surface, letting all the active torps acquire the enemy sub, putting it into a soup of it's own torps.
Easy peasy...
