In this example, your destroyer is tracking the U-boat with sonar. The U-boat is traveling north, and you’re approaching it from its back-right side with the intent on making a drop as it continues north.
As most frustrated captains know, it never continues in a straight line, and will make a hard turn (left in this example) that you can never follow which ultimately results in a loss of sonar contact. What to do?
1. Select sonar relative bearings
Set your sonar to relative bearings (this is one of the first things I do when a mission starts).
Why? The benefit of having relative bearings in the sonar screen effectively turns the sonar display into a top-down view of your ship. The 12 o’clock position is your bow, 6 o’clock is the stern, 9 o’clock is your port side, and 3 o’clock is starboard.
This lets you quickly set your search pattern immediately based on the orientation of your ship, instead of determining what heading you’re on, finding that heading on the wheel, and trying to set your search pattern.