Sinking Times and Torp Expenditure

[Walruss]

Hey guys, on my first (modded) patrol... I'm running BARF and historical u-boat mods (and a few others here and there but nothing else that might affect combat in this way)... I have played a SH$ and SH@ before, but a while ago and not quite so seriously... anyway I just encountered my first target on my first (modded) patrol - a Cimmaron class tanker worth 7,600 tons... fired a two-torp spread at ~1600 meters after sneaking up on it, and was rewarded by two hits, one far aft, almost at the props, and one at the bow, both possibly a little shallow... the whole on the bow was just visable above the waterline.... after waiting around 5-10 minutes she was still making headway (albeit only at 2 knots) and showed little signs of slowing. The seas were fairly calm, so I dropped a third torp, which she almost dodged (wound up taking it up the arse). 15 minutes later (and after some showey pyrotechnics) the bow finally disappeared below the surface of the water.

My question is this: Was the third torp excessive? ow long should you loiter and at what point do you decide the ship is still sea worthy enough to warrent another torp? or prefer deck gun use? I feel I may have wasted a torpedo on a stricken ship.... not sure

On with the patrol!

Walruss