[TorpX]

There are 2 basic flavors of 'sonar' in the game.

1. Passive sonar.
This is often referred to as hydrophones. This amounts to the sub hunters listening for noise you make. You can reduce this possibility of being detected by going slow, say 2 or 2½ kn. 'Silent running' shuts down repair work, and stops things like torpedo loading to reduce noise, but if you go at 4 knots, you are still making considerable noise.

Surface wave action creates noise, so weather can interfere with the use of passive sonar.

Passive sonar gives a bearing, but doesn't give much information about range.



2. Active sonar.
This is sometimes referred to as 'pinging' or echo-ranging. Being quiet will not prevent the enemy from locating you here. The best thing you can do is to turn your boat to present a narrow profile, so there is less surface area for the sonar to bounce off of.

Active sonar will give both bearing and range, so is a more effective tool for locating subs.

Going deep, deep enough to be under a 'thermal layer' will greatly reduce the effectiveness of either type of sonar, but changing depth in itself doesn't really help. In either case it is better not to be too close to the searching ships.



I'm sure someone will be able to give more in-depth tips for the game.