[maillemaker]

Sorry Steve. That tweaking is not neccesary. IF the uboat is on a course perpendicular to the target's track, AND IF the periscope/UZO is pointed to 0, (both requirement which I highly advice to do with type 1 torpedos) THEN you should set the AOB dial to 90 port/starboard. If the uboat course is different, or periscope not on 0 (anymore), then 90 AOB is not correct. In any event the AOB dial should be set to whatever the target shows when he will be on the periscope line. (or the angle that follows from the mapdrawing) There is no tweaking neccesary, not even after the gyro angle is set to 0. Other than realising you made a mistake due to the visual image not matching at all. The change of the AOB dial because of it is automatically (assuming the TDC switch was indeed set to AUTO), and appropriate. Since when the gyro angle is set to 0, then the periscope is pointing away some degrees from 000 (and the AOB dial will correct for this), which is exactly the lead needed to make the torpedos arrive on time on target.

So you're saying the Periscope should be set to bearing 000 before manually adjusting the TDC to AoB 90?

Steve