Merchant didn't sink properly
 

I put two torps into a merchant in early 1942 and half of it was underwater, but it kept shooting at me. It didn't even get lower into the water when I shot at it and elapsed time. Is this a bug? Does the realistic physics mod cause this issue?

Thanks

Which modes do you play?

a couple of points to make

the compartments you damage and flood are what determines if it sinks or not

the cargo a ship has can determine if it sinks easy or not so easy

oil tankers that don't explode are helped to stay afloat by the cargo (oil floats on water)

always spread torpedo out and not hit the same spot with more then one torpedo. if using auto target this can be a common mistake so lock on, unlock and shift target point, then fire, to hit different spots.

lastly, if the water is very shallow such as in port a ship can land on bottom and not register as sunk because the game wants to see it sink to a preset depth to signal its sunk. in these cases it must be sunk by damage and not by flooding. also, until the ship "registers" as sunk the crew will still be on deck and will fire at you, if you see crew on deck its not sunk yet.