Well I have a similar problem right now, only it’s not inside a harbor. I’m doing a patrol off the Philippines and two days in I met this lone large tanker, and it just refuses to become my victim. I saved moments before so I’ve been able to ponder about it a few times now. At most I send 6 torpedoes, all impact and explode, but does she sink? No, even though half the boat is gone, seriously I don’t think I’ve seen any boat with as much damage as this before, but she just settled a little lower in the water and doesn’t even slow down. Note I’m not using any mods affecting the sinking dynamics. That is stock.
She doesn’t even attempt to get away from me either. She just continues straight on as if nothing happened. After firing six torpedoes and seeing the boat just keep on going I decided to observe her for about an hour on TC. Silly I thought that a boat with no hull would eventually sink. Well an hour later (game time) I had enough, but since I was out of torpedoes and I used all my deck gun shells the day before, I had to ram her on ahead flank. Well apart from killing a few of my crew I managed to get her to lean to one side, and in time she was almost submerged, but she still took her time going down.
Then when she eventually did, it did not register. I got no “enemy unit destroyed” message, no wreck update on my map, not even in grey. No tonnage was added to my log. It’s as if the boat never was. Since then I’ve tried various methods, such as different torpedo depths, different torpedo spread angles, different submarine attack angle (head on, side, from behind) and different ranges. Seriously it’s a tanker, there is a chance it holds fuel, I mean those times I do get it to explode there is a huge fireball indicating a secondary explosion. However no matter what I try it never registers as a kill. I’ve now decided to just leave it alone and use my last set of torpedoes on something else.
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