I made various setups with ships and submarines in various depth. The ships either are stopped o rare sailing. The ships are using either hull sonar only, active sonar or variable depth and hull sonar in common. The submarines cruising towards the ships in shallow, just-over-layer, witihn-layer, just-under-layer and deep as possible.
Here are the results for stopped ships:
- StoppedShip.png (53.63 KiB) Viewed 1915 times
- SailingShip.png (28.5 KiB) Viewed 1915 times
- If ship has only hull sonar or active sonar, best place for subs is under the layer and deeper and shallow is worst.
- If ship uses variable depth sonar, best place for subs is within layer, worst place is under the layer in convergence zone and shallow in close range
- Question: In close distance it seems VDS have no advantage to hull sonar – is this to be expected?
- The use of active sonar turns passive sonar off.
- Question: Is this really the case IRL? Can’t the frequency of active sonar have filtered out?
- active sonar is always worse than passive sonar, except if pinging ship is fast and sub is very deep. The only reasonable situation to use active sonar is to get an exact range fix after the sub has been spotted by passive sonar already. (!?)
- For search results it makes no difference if a ship stops or is creeping around.
Things I am wondering about:
- There is a lot of findings at 12.8ish in shallow waters and 9.8ish in deeper water regardless how loud the sub is. Is this to be expected? For me it looks like CMO is using fixed thresholds for detection rather than calculations.
- See picture below. The outer convergence zones are from 27 – 32 nm respectively 56,5 – 61, nm. When a sub was detected picking up and loosing fitted quite well with that. The inner sonar zone has a radius 22,3 nm. Regardless how loud a submarine was, it never managed to detect a submarine further away than 12.8 nm. The range from 13 – 22 nm seems to be blind.
- SonarTest.png (770.02 KiB) Viewed 1915 times
