At 100 %, go to the navigation station and then:
1. When a new minute turns into the clock, ask the sound operator to give you a new bearing to the target.
2. While waiting the answer, MARK YOUR POSITION
3. Use the angle solver to mark the bearing given by SO.
4. Range you have to quess. Before you start plotting, have your own listening session to get a picture.
5. Repeat from 1. to 4. few minutes later.
6. Again, few minutes later, repeat the proces. NOTE: It's useful to keep the intervals of markings steady, for example 3 minutes. 3 minutes 15 seconds system I haven't find useful becaus a need to use a chronometr.
7. After you have marked targets bearing 3 or 4 times, it's time to try to make a motion analyse. That's not an easy task. If you are listening freigter, you could give it an estimated speed, for example 7 knots. But how do you know its course? Bearings won't tell it you. And there is also great error in bearings you can get from the sonar.
SIMPLE RESULT: To estimate the RANGE is easy but to find the targets track you need also maybe a qipsy with her crystall ball. Errors in estimated courses (tracks ?) can be as huge as 45 degrees, what I have seen. So, I usually do not try to do it. Not with this sonar.
I hope you understood, my english is not too good, sorry.
RC
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