Question: FFG Active sonar - single narrow beam detectable?

[SeaQueen]

Originally Posted by Wildcat

I am curious about this.

Let's say I have a passive transient contact i.e. torpedo fired, or brief cavitation.

...

If any submarines are behind me when I do this, are they going to detect it? Are submarines outside of the beam able to detect the active sonar ping?

If a submarine has shot a torpedo at you, you've already been detected, so who cares?

It's generally best to work under the assumption that an intelligently driven submarine will almost always detect you passively, somehow, before you detect them. Stealth is not a surface ship's strong point.