Realistic Sinking Time - do you have it turned "On" or "Off"?
That will influence how long a ship stays active and/or afloat after its hit.
I usually give a target 1 eel initially, depending on its size and what's going on around me, then follow along for awhile and wait for it to stop and then sink. I can also surface and use my gun if I'm impatient.
In a convoy attack, I pick the larger ships and give them 2 eels each. Even that is no guarentee they'll go down, or that I'll get credit when they do. While the escort and I play the dance of death, the ship and I can get beyond the programmed separation distance for sinking credit.
I've seen torpedoed ships run on a bit and then stop. Most will sink, but a few will stay there indefinitely until I put one round of cannon fire into them. A few times, a single round from the AA did the trick; just something to push it over the edge. Must be a programming thing.
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Raptor
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