I'm not entirely sure this counts...
Found a convoy, went home. Killed two escorts, third one sails over my torpedoless sub depth charging. Blow ballast underneath flower corvet, try to ram. Chase ensues. Both of us shoot anti-aircraft guns, I ran out of Star Shells on my deck gun, and I tried to ram him.
It didn't do anything and then I broke off, because I could see I probably wouldn't be pursued. (He had the front turret working)
Edit: I did kill all his guys except two in the turret.