Undetectable while submerged and running silent

[reddogut]

Not sure if this is the correct forum...

And not sure how realistic this is. I am at about 120ft in 140 foot waters, engines off and running silent while an enemy ship patrols overhead.

They are not actively pinging, yet they detect me everytime. I thought that as long as the enemy wasn't actively pinging and I was running silent with engines at all stop sitting almost at the bottom, I would be a bit more undetectable than that.

Is there a way or a mod I can load to be more undetectable? I don't want to be invisable or invincable, but I would like to be a bit more undetectable.

[CaptBackasswards]

Someone will probably chime in with more knowledge on this subject than I, but there are passive and active sonar. Escort usually only ping when they have picked something up from passive sonar or hydrophones. Sea state and the speed of an escort can make it hard for them to pick you up. I've had escorts cruise right on by - near me - and not hear me. But there is usually one escort that is moving slow and/or stopping ocassionally and listening.

[Keelbuster]

I guess in theory, if a your boat is all stop and the crew is silent, and the escort is unawares, then they shouldn't detect you (given WW2 anti-submarine technology). However, if they are suspicious (e.g., searching for you) then you're kinda busted. I mean, if an enemy DD is driving over top of you, you're in a bad situation. I acknowledge that at times I've felt that the AI can detect you without using active sonar - they just seem to 'see' you. But that's usually in cases where I have blown my approach and got too close. Also, I use TMO, which has notoriously sensitive DDs. I guess I just chalk it up to the concept that 'silent running' really isn't _silent_. That if you violate a basic circle of proximity to DDs, they will detect you, regardless. Mind you, I kinda like the idea of going silent and having a task force drive over me without detecting me.

What mods are you using?

[reddogut]

No mods. Stock 1.4.

I was kind of wondering if there was a mod for this kind of thing.

[Keelbuster]

No mods. Stock 1.4.

I was kind of wondering if there was a mod for this kind of thing.

Hmm. I had the impression that the AI was more or less deaf (and crazy?) in stock. I'd say install a mega-mod and see how it feels. Sure, you'll die more, but hopefully for good reasons that you can chew fingernails over. Don't count on UBI to produce a half-believable simulation.

[Diopos]

In real life situations a submarine (more so a WW2) can never go completely silent. "Silent running" means all but neccessary noise producing equipment and crew actions must avoided. That does not imply that turn off the key and hold our breath. Many sub systems contlinue to function. Depth keeping requires continued balancing of internal tanks and some speed and dive plane manipulation and so on. In your example your sub is hovering 20 ft over the seea floor. Depth keeping would be a hastle and more or less a continuous job!
Another source of concern would be the interaction of the sea with the hull itself. Even if you set you speed at 0, the ocean is not a "static tank" micro currents or whatever "move" over your hull, etc. Also your sub may alter the "back round" sound of, say, the sea bed (as received by the destroyer). All these, means that the "sonar" image in the vincinity of a "silent running" and almost stationary sub cab be different from the general ambient situation therefore the sub is detectable.

So the ingame situation you describe is not an unrealistic one ( based on the above).

[Frumpkis]

Engines off might actually be the problem. If you're deep enough to be under the thermal layer (are you?), the best tactic is to keep moving slowly away from the last position where the DD's think they detected you. They might just be pounding the last spot where they saw a torpedo launch, or whatever you did to attract their attention, and you just haven't moved far enough away from that zone. They'll fixate on "last contact" and poke around in that area, if they don't have a fresh contact.

Even with fairly aggressive mods like RFB and (especially) TMO, I can usually creep away on silent running and ahead slow. The places where I get nailed are usually shallow water where I can't get deep enough to be under the thermal layer.

[magic452]

At 120 feet you're not really very deep. That's keel depth and that means the periscope shears are about 100 feet, not very deep at all.

Also the DD sonar heads are no doubt 6 to 10 feet below the surface so that's even closer. Add to that you're not under the terminal layer. If there are calm seas even worse. As stated above you are still making some noise.

All in all not a good position to be in. Certain death in TMO.

Magic

[peabody]

I tend to agree with Frumpkis about the stopping.

Another one that I have not tested but someone quite a while ago commented is leaving "auto load" ON for the torpedoes. Even if they are not loading I guess the game takes it into consideration as far as how silent you are. But like I said I haven't tested it. And I guess it would be almost impossible to really know for sure, since every situation is different.

If you are early in the war and it is a Somers DD then they may just be hitting the area where they think you are. They are almost deaf. Later in the war the Clemson and Fletcher are better (or worse depending on your point of view).

Peabody

[Bilge_Rat]

even in stock 1.4, the escorts are not deaf/dumb.

To increase your chances of not being detected, the best course of action is to dip below the thermal layer & go to silent running.

"silent running" basically gives you a stealth bonus and reduces the passive sonar range of enemy escorts. You can see it visually in SH5 w. map updates "on". From my experience, it appears to work the same way in SH4.

Although in RFB, which is what I use, you can still be detected if the escort is close enough.

[Capt. Morgan]

...

I was kind of wondering if there was a mod for this kind of thing.


Not for 1.4.

If you get 1.5 there's Nicolas's "AI fix" test [http://www.subsim.com/radioroom/showthread.php?t=163340] , and AOB/Sonar fix - current release...[http://www.subsim.com/radioroom/showthread.php?t=164448].

As long as you keep your speed very slow (maybe 2kts absolute max.) you can move with inpunity around un-alerted escorts. The instant they become alerted (by high submerged speeds, firing torpedos, prolonged periscope exposure, etc) you're back to the normal A.I. behaviour.