[FAdmiral]

Being stopped at PD or somewhere below (still above thermal) running silent
should keep you from being heard vs. hydrophones but the sonar will bounce
off you and give a detection signal to the enemy. If you click on the approaching
DD, you will see 3 circles, the largest is a 360 deg. visual, the next is a circle with
the aft missing (passive hydrophones) and the 3rd is the sonar half circle in front
of the DD. This gives you an indication of basically where those sensors are for
that certain DD. But there may be other factors involved too. Crew experience,
ship speed and possible some random issues. I'd like to think that the game AI
would NOT make all those detection methods too standard. I like the random so
that you will not always know just where & when you will be detected...

JIM