I just caught a pack of British subs at anchor and put a few torpedoes into them and ... nothing!
I mean, I shoot them straight, ~0 deg. on the bow from ~600m while standing still at periscope depth. By the book. Multiple hits into their hulls. Saved, reloaded, tried-again from different positions, torpedo depths -- same result, none of them seem to die.. At most, they start to run around like headless chicken at odd angles with their props in the air.
Context:
100% realism setting; Oct. 1939 (with a few tens of kills under my belt)
SH5 v1.2 from Steam, with no mods.
It must be a bug, right? Please tell me it's a bug, 'cause I've exhausted all in-game-possibilities (on one attempt, I even surfaced and put a few AP rounds into a sub's waving tail -- I don't know if it did any damage, 'cause there's no life bar in 100% realism setting) and want to get back to a normal life, one not marred with sub-on-sub action