Your plot can be absolute or relative. Absolute means you plot based on your sub's true course, and must therefore convert relative to true bearings each observation. Relative (What I do) means:
1.- Draw a line with ruler, vertical (North-South)
2.- Take first bearing and range. Start the chronometer simultaneously.
3.- Starting from the beginning of your vertical line, use the ruler to plot the bearing line in the proper orientation. Since your bearings to target are zero to 359 and your vertical line is north-south, you can read directly.
4.- 3 minutes later, reapeat processof taking bearing and range. Now, to plot it in the map, you will need to see your sub's speed first. Let us say you were doing 6 knots. Star from your first plot and go up 600 yards. That's teh starting point for your second plot.
Repeat as many times as you want, and then draw a line from the first target position you recorded, to the last, averaging along the various results to make it as straight as possible. Now you have an average distance, a relative course, and time. YOu can get speed and AOB instantly, and by converting to your sub's true course, the true course of the target (If needed).
I only use plotting as auxiliary. I try normally to get on a constant bearing to target and estimate AOB, then calculate speed with my MK3 course finder, use the game tools at the same time, watch the position keeper versus real situation of the target, and make plot. An average of all four things usually gives a very good solution
