Few questions about weapons

[Dr.Sid]

You talking about ruler .. you mean frigate TMA ? That is pretty messed up. Luckily you don't need do TMA on frigate most of the time, as you have active sonar and helo.
Sure, even on subs you rarely have chance to stack all the dots perfectly. Usually you only need last dots to stack, as the target may change speed and direction, in which case it is impossible to stack all the dots. Also you have to make change in direction or speed during collection of target bearing, otherwise the solution will not be possible.
You can also use some estimates to help you .. for example you will usually detect targets at some distance. You don't have to know speed and course of the target very well, as it will most probably change in the moment he detect the torpedo. Sonar can provide you with classification and speed information. You can use spherical and towed array to triangulate. Or use UUV to triangulate (interesting method for Kilo, which does not have towed array). Sometimes you can upload probable position of target into link, and let other friendly platforms investigate.