SH4 sonar failure
 

I can't hear ship contacts on sonar. In this video I'm 3000 yards away from a ship. I go to the sonar station and there is no sound on that bearing.
The first time this happened I ran into a Dutch tug and wanted to make a practice approach using my sonar. I could not hear it on the hydrophones. I thought maybe it was because the target was so small.
Two days later I ran into this contact. A small Dutch freighter, I tried going to 100 feet, all stop, the works. I can hear my own screws, but no targets. Note that the light does not come on when on target bearing.
Link is a video I made of the problem. Any help would be greatly appreciated. The only mod running is Trigger Maru Overhaul.

https://youtu.be/XmsM_hthZxg

It is a game bug. Try lowering the periscope before manning the sonar. For some reason, only one sensor can work at a time. There are also some ships that don't show up if traveling below a certain speed, although your sonar man should pick them up.

Apparently FORTSU has fixed this bug.

Thank you.. I'll get it.

FOTRSU is Fall of the Rising Sun - Ultimate. it is a mega-mod with it's own thread.:Kaleun_Salute:

Ahoy 4H,
some of what you are experiencing is part of the SH4 programming: some surface ships will not be detected by sonar. these include fishing boats, crab boats, junks, sampans, tugs, etc. whoever did the programming at Ubi either didn't think to include it or didn't think it would matter.

also, surface ships that are stationary or moving very slowly will have no sound to detect. so when you venture into your first port to take photos, you will submerged and using sonar to see what's there. you will here nothing...unless there is a patrolling DD/DE.

what speed was the Dutch freighter making when you were trying to pick her up on sonar? chances are she was doing a knot or two.
anyway, what you experienced is baked into the game and you (we) have to work-around it.

have fun. good luck. :Kaleun_Salute:

It's not really "fixed" in FotRSU KaleunMarco, though CapnScurvy did make some of the "guilty" ships "noisier" so that they are easier to hear... As Bilge_Rat points out, if the game can "see" the other ship, it will eliminate the sonar lines, even if your periscope is not up. Sort of like the XO has the other scope up, "helping" you out... so go just a bit below PD, and you should get the sonar lines back. Shouldn't be that way, but... it is SH4... As for the coastal ships not making noise, those are Type=104, which are "silent" on purpose. Some sampans though, did have little diesels in them, so... go figure. :salute:

Downloaded and activated Fall of the Rising Sun.

Ran across another tug (same as the first contact in the above video.)

Went to periscope depth and listened in with the hydrophones.

I could hear it!!

That is 100% better than before.