I find klh's strategy better. This is what i do and believe me it has proved to be very effective: get a position in front of the convoy, dive at 100 meters when your distance from the nearest visual contact is 10000 meters, turn the Uboat to where the convoy is heading and then keep contact using the hydrophone (this way you will also allow you to ''keep an ear'' on the destroyers, run at ahead slow=2 knots). Go to silent running when the nearest warship contact comes to middle range. When the nearest merchant contact comes to middle range go to 80 meters. ''Follow'' the destroyers and go to periscope depth when they pass above you or they are 270deg or 90deg port or starboard,respectively . Choose your targets and when they have finally come to bearing 330deg<periscope bearing<30deg -meaning they are in front of you-begin the attack procedures!
A clever way to sink fat ships and disappear after the attack in the confusion while the destroyers are spitting elsewhere!
