NEW TIP FOR SINKING SHIPS ON THE SURFACE IN MAXIMAL DIFFICULTY: this shot is normally impossible to do in reality, because the list of the submarine does not allow it.
However, in SH4 it is possible to do this shot using the game's pause option

. But captains, I advise you to carry out surface shots only at night and when visibility is almost zero, because during the Second World War cargo ships were equipped with deck guns like German submarines

.
Cordially
Captain PUJOL