Intercepting targets

[Egon01]

Hi

I have long break from SH and now from few weeks I try to learn almost everything from beggining. I did many tutorials and I do not have problems with manual TDC and etc. I use patroling method which I found on this forum (I draw 18km circles and move to centers of this circles, submerge and listen with my hydrophone), this method is very good, I found many contacts using this but problems comes when I find the contact. I can't find intercept course to him, I know only bearing (don't know distance, so I can't find his true course). How do you behave in this situation? What should I do? I did tutorial with finding out intercept course but in this tutorial I know enemy ship course and speed...

Please help

Thank you

[gAiNiAc]

When you first find the contact estimate his range and then mark him on that bearing. Continue observing the target for a few more minutes (10 is good) then range and mark the next bearing.

Draw a straight line through the marks on your map and you now have the targets course. Next just plot your intercept.

[Egon01]

Problem is that I don't know how to find range to him. I know I can do this using hydrophone but this thing shows difrent ranges every time I ping.

[Zero Niner]

What I do is to use the tip of the sonar contact line as a proxy for the ship's location. Get at least 2 (preferably more) plots and do a "best fit" line. You'll then have a rough indication of the ship's course.
Plot an intercept, then after a while (say 15 min or 30 min later, it all depends on the current situation) repeat the process to refine the solution.

Note that sometimes the ship changes course, and that will throw off your solution and you'll have to start all over again.

[gAiNiAc]

Originally Posted by Egon01

Problem is that I don't know how to find range to him. I know I can do this using hydrophone but this thing shows difrent ranges every time I ping.

Learn how to use the stadimeter........

Practice makes perfect..............

[Pisces]

This technique is what you are looking for:

http://www.subsim.com/radioroom/show...mittelwaechter

The rapidshare link (to a self-playing video) in the final message (mine) is still alive.

Or, using the following tool described in this message (no, I'm not self-promoting for vanity reasons) gets you the target course only. (which is basically the same as halfway in the video upto the point he starts moving his sub, just a different graphical way) No range or speed is given with this! That needs to be figured out from succesive bearings taken from different positions.

[Rockin Robbins]

Using sonar to find targets is slow, has too low a range and sets you up for the range problem. It also keeps you from finding targets because you have to take all that time to submerge, listen, locate targets and if you use Pisces' method, triangulating them.

Much better to join the twentieth century and realize that your boat is far superior to the U-Boat you are imitating. You have radar. Stay on the surface at cruising speeds, set radar for max distance and cover 100 times more water than the sonar technique. Radar has much better resolution than sonar, will even show your the exact disposition of ships in a convoy and is the gold standard for finding range. What's not to like?

Don't misuse your tools. Just because sonar conceivably can be used to find targets doesn't mean it should be used that way. It's a slam dunk. The number of targets you find is proportional to the number of square miles of ocean surface you can search. Underwater sonar search is so slow, it isn't even worth consideration as a search technique.