Oh yes! I was trying to evade 2 DD convoy escorts and fogot to check the silent running mode. Couldn't figure out why it was so hard to throw them

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Anyway I was lurking about 200m down (it was early war, so the DCs couldnt reach me). After about 3 hours of constant bombardment, they both ran out. It was easily over a hundred each. They then circled me for a while after that before i finally noticed my crass error. Then they went to rejoin the convoy which by now was about 60km away.
I figured their heading would tell me which way the convoy was, so i plotted an intercept for the convoy and about 3 hours later ran into them again.
So i dived, knowing full well i was safe from them, had a peek with my periscope and saw one of them was on fire. A couple of minutes later the other one was on fire too.
I realised there was a gun battle going on, and soon enough i noticed another type VII was on the surface dukin it out with the DDs. The VII won the battle completely. I was just about to surface and join in when i realised the two destroyers were sinking. Awesome. What a mod is GWX