The way I make low visibility shots is using the vector analysis attack method, a constant bearing attack. Once you plot heading and speed of the target you set up an attack using the method given by Rockin Robins at this link
http://www.subsim.com/radioroom/show...&postcount=204
The third one down, Vector Analysis. Draw the triangle as shown.
Next using the protractor tool plot the same aiming bearing using your sub as the apex and the impact point as one leg and the lead angle line extend to the target track as the second leg and where they intersect is the firing point. What you are doing is making a smaller triangle inside of the large one.
You will shoot from the Nav. map. When the sonar trace reaches the firing point SHOOT.
Once you have plotted this set your periscope to 0° for bow shot using auto targeting. For manual targeting you would aim the Scope up the aiming bearing.
Make sure AoB is 0, Speed is 0. The torps will shoot straight out the front.
The closer you are to the target track the better the results.
You just did a manual targeting shot.
Clear as MUD isn't it. I'll have to learn how to post a picture. If you see it, it's very clear.
It sounds complicated but with a little practice it is very easy.
Works very good on single ships. In a convoy you will have to pick out one target and plot it. I use this method all the time, good weather or bad.
Hope this helps Magic452