The TDC helps you with your target solution.
You have to find the distance to target, as the angle on bow (AOB) and the speed of the target.
This data is/was necessary to make the TDC calculate the correct turning angle for the eel after leaving the tube.
If you want to shoot straight and hit the target perpendicular, you have to position yourself correctly and translate the speed of your torpedo into range and accordingly the speed of the target into its range/traveling distance to meet the torpedo and the ship at the impact point.
You have to calculate the bearing showing in your periscope matching the position of the target in relation to the position of your U-Boot/your torpedo in relation to the speed of both objects.
Assuming the ship moves at 10 Kts and your torpedo runs at 30 Kts.
The ship moves 300 meters while your torpedo moves 900 meters.
What is the correct angle in your periscope to release the torpedo?
