JTS Wolfpack - Passive Sonar

[Lethal]

Greeting U-Boat aficionados!

Those who have been interested in U-Boats and U-Boat games will be familiar with the concept of: if you cannot see them on the surface, dive and listen on passive sonar.  If JTS Wolfpack is to be taken on face value, this is a misnomer.  I have never picked up a convoy (much noise) or a single freighter on passive sonar.  The only way I have been able to detect the possible location of the enemy is via their ASDIC pings (active sonar) - i.e., the bright green line.  Passive Sonar, the dark green line, can only indicate targets when they are well within torpedo range!

I am curious about the performance of active sonar (bright green) as depicted in the game.  A U-Boat is supposed to be able to detect active sonar at twice the effective range, ie it can detect active sonar before the pinger detects the U-Boat.  The active range is 5000yds, about two and a half nm/two and a half range dots.  I suspect that it works on the fringes of 4-5000yds but I'm not so sure about 10000yds.

I would be interested to hear other players experiences of this.  Perhaps I am misreading something.

Presume sonar value in the Parameter Data is "active".

thx

Image re passive sonar performance


Gruppenhorchgerat (GHG)

The standard U-boat hydrophone, the GHG (Group Listening Apparatus) was installed in U-boats from 1935 onwards. It consisted of two sets of hydrophones mounted on each side of the bows, covering two arcs of 140 degrees on the sides of the U-boat. Because the hydrophones could not be rotated, the triangulation was most effective with sound sources coming from the sides, with deteriorating accuracy as the source moved to the front or rear of the boat. Consisting of 24 hydrophones, the GHG could pick up lone vessels up to 20 kilometers and convoys up to 100 kilometers away. The detection range however was also dependant on sea conditions.