Hydrophone surface range

[Inajira]

I read it on these boards recently that the hydrophones have a very short range while the boat is surfaced. I was under the impression that they did not function at all while surfaced. I tried testing this during night attacks in the fog and rain (one cannot rely on much else), and found I could not pick up ships even under 1NM distance. So is there a range while surfaced or not?

[Krupp]

About listening devices, The GHG (Gruppenhorchgerät) and later on the Balkongerät were installed well below the waterline, so you could assume that it's possible to hear targets even if you are surfaced. Why shouldn't they work?At least in the game you can if you are stopped or slow speed. The KDB (Kristalldrehbasisgerät) is installed on the upper deck (bow) and can be used only when submerged. I'm not sure how far away you can hear with the GHG when surfaced. The hydrophone operator called "Grosse entfernung" so it's over 3000 meters I think. It was heavy fog so hard to tell the real range.

[NastyHyena]

I would think the GHG could listen on the surface, but on anything other than a glass-calm day at a standstill would be useless due to surface noise.

[Marhkimov]

(In real life) with under-keel hydrophones, it would have at least been possible to hear something.

But in SH3, hydrophones don't work if you are surfaced.

[Inajira]

Well I checked this out again over the weekend. Seems my sonarman can pick up contacts from time to time while I'm on the surface and moving, but I can hear nothing when I go to the hydrophones room. I'm using the earliest type (the GHG I think?). Thanks for the help.

Slightly off topic, when he calls out Long, Medium or Short range, what are the actual range brackets in metres?

[Marhkimov]

excerpted from contacts.cfg:

Short=1000m
Medium=3000m
Long=20000m

[Krupp]

I stand corrected. The hydrophones are useless in the game when the boat is surfaced. But It worked once, really :88)

[Marhkimov]

The hydrophones are useless in the game when the boat is surfaced. But It worked once, really :88)

I believe you... Sometimes when it is really stormy weather and the u-boat is being tossed around in the waves, it is possible to become "submerged" for a few seconds.

So during those few seconds, your hydrophone operator might pick something up...

And then you resurface from the waves and were misled to believe that hydrophones work on the surface.


Don't worry. It happened to me... I was confused too. :D

[Inajira]

Ah that was probably the case. Been getting a lot of stormy foggy generally crappy weather lately. Gives me a chance to work on attacks during fog. Even at periscope depth my sub tends to jump up and down, I suppose the swells play a part that deep as well.

[The Avon Lady]

The hydrophones are useless in the game when the boat is surfaced. But It worked once, really :88)

I believe you... Sometimes when it is really stormy weather and the u-boat is being tossed around in the waves, it is possible to become "submerged" for a few seconds.

So during those few seconds, your hydrophone operator might pick something up...

And then you resurface from the waves and were misled to believe that hydrophones work on the surface.


Don't worry. It happened to me... I was confused too. :D
Yes, and your diesel engines will cut off and go back on again, too, in such storm conditions.

[Inajira]

Yeah and I keep losing my periscope "lock" on surface ships in stormy conditions :doh:

[The Avon Lady]

Yeah and I keep losing my periscope "lock" on surface ships in stormy conditions :doh:
Of course! Your scope is bobbing below the waterline and you're losing visual contact with the target.

In principle, that's no different than locking on a target, diving to 150m and surfacing again. There's no differentiation in-game.

[Inajira]

Well the way I see it the "lock" is not really a lock per se, but one of my crewmen keeping the scope centred on the target while I ask the WE for his target solution, go make coffee, and wait for the torpedoes to hit :D So the way I see it, it shouldn't lose the lock (despite the waves washing over) because there is supposed to be an "intelligent" officer dedicated to the task. Anyway will just have to live with it!

[finchOU]

ah, I think the lock is a cheat personally....anyway...I have a question which I cant seem to find the anwser to...

does depth have any bearing on hydrophone range or clarity (which should increase listening range). I was wondering because when I listen for contacts it is normally at Parascope depth.....I would think some surface noise should be problematic at 12 meters...verse say...25 meters....anyone have the short (and/or long anwser to this one?

[Sailor Steve]

(In real life) with under-keel hydrophones, it would have at least been possible to hear something.

But in SH3, hydrophones don't work if you are surfaced.
No, it wouldn't. The noise of the water against the hull blocks out sounds. Think about it: a destroyer has it's sound gear mounted under the keel, but they can't hear other destroyers, or battleships, or surfaced submarines.

[Krupp]

German U-Boats were instructed to use electric motors during (night) surface attack IF: The conditions for sound-locating are good(*) and that enemy sound-location is anticipated. Sea is calm. Target speed is slow and the U-Boat in relation to the target will allow attack.



*
- acoustical conductivity of the water (temperature, salt content, motion of the sea)
- interference level of the sound-locating vessel
-volume of the sound to be located

Was it only a suggestion from behalf of the germans that they could be heard when running on surface or was it a real threat? :88)

[Saturn5]

On a calm day the engine noises of surface vessels can be carried over long distances. If one is on a stationery or noiseless platform, one hear engines of vessel before you can see it.

Therefore I think the advice of using electric engines is not that bad. But I have never been on a ocean. I do not know the elements there.

[Krupp]

In this case of being sound-located because of the diesel noise wasn't concerned to be a threat heard via air but underwater (hydrophones).