Target speed calculation made easy

[Pisces]

Originally Posted by commandosolo2009

could you be kind enough to make one for the metric system. And please explain what is bearing change.

Yards are about 1/10th shorter than a meter. So take the metric distance in meters and add 10% to find the line in the table.

A bearing change is the difference in the viewing direction through the periscope (or TBT, hydrophone sensor, etc.) of 2 moments you point it at the target.

Imagine standing alongside a road with a car approaching from your left. As it comes closer, the direction to it(=bearing) slowly starts to drift to one side of you. Once it passes you, the direction moves at it's quickest. (Be careful not to strain you neck ) As it has passed you, the changing of the view direction slows down again until it is at the horizon. The table assumes you measure this view-direction change while he is passing the moment when the AOB is 90 degrees.