Hydrophone range

[Kargul85]

What was the range of the hydrophore in reality? I once watched a document and the guest said that the sound carries several dozen kilometers and in the game 7-8 km seems very little (sorry that I write in kilometers, not miles). Poorly detects ships.

[Salt Strider]

The signal gets weaker the further away it is, hence why you get such crummy readings when ships are near the edge of the hydrophone's reach. Also, the model makes a difference as well. Unfortunately that's all I know and I was unable to find anything online that would serve as reliable, but awesome question nonetheless, you got me thinking and wanting to know more about it.

[Bluehelmet]

Next update will drastically increase the range so they say. Maybe it will be better then.
In general I have the feeling the game started of small and more as a tribute to Das Boot then a real simulator. When it got some attention and showed potential they seem to have shifted more towards the sim aspect. Just my 2 cents(eurocents ofc).

[Kargul85]

Originally posted by Bluehelmet:

Next update will drastically increase the range so they say. Maybe it will be better then.
In general I have the feeling the game started of small and more as a tribute to Das Boot then a real simulator. When it got some attention and showed potential they seem to have shifted more towards the sim aspect. Just my 2 cents(eurocents ofc).

Thanks for the information, as if I could even find the direction, it would be great :) because this is how you swim and swim and luckily hit something

[verzinkter vierkantstahl]

you could ask on the discord, there is a "historical-discussion" channel for something like that think

[PafunaMT]

Hydrophones aren't quite 'range' devices, per se, but think of them in terms of sensitivity.

Sound waves, much like light waves, follow the square inverse law (see https://www.acousticalsurfaces.com/acoustic_IOI/101home.htm for a primer), which means that the sound wave weakens greatly over distance. The technology of the hydrophone is geared toward detecting those residual waves, so the more sensitive the hydrophone is, the weaker sound waves it can detect.

Think of a hydrophone like an ear; the more sensitive the hearing, the softer noises can be heard. The WWII technology was crude by today's standards, so the hydrophones were comparative 'tin ears' back then.

Hope this makes sense.

[Ruby]

HI Kargul85,

Look at the tooltip and/or the info of the hydrophone. There you will find that the hydrophone will hear > 100 km when the station manned by officers and sailors.

Within the displayed hydrophone radius is the officer able to identify the detected noises.

Cheers Ruby

[athenian]

Keep in mind that you will NOT be able to hear anything in first person, regardless of the fact that the operator is detecting sound signals. You can only hear in first person if you are within the blue circle emitted by the target. This is supposed to be addressed in b129.

[Geandily]

Originally posted by athenian:

Keep in mind that you will NOT be able to hear anything in first person, regardless of the fact that the operator is detecting sound signals. You can only hear in first person if you are within the blue circle emitted by the target. This is supposed to be addressed in b129.

Oh man no wonder I havent been able to find convoys manually with the hydrophone haha

[Jack Schitt]

Originally posted by Google Search Result:

50 miles
By the end of World War II, German hydrophone operators could detect enemy surface ships at ranges of as much as 50 miles. Sonar was a mixed blessing for submarines. It could be used to give an accurate range and bearing on a surface target, but the emitter also provided a bearing for the enemy's A/S forces.

Citation Source[fleetsubmarine.com]

Sound travels through water further than it does in air. Wales use the sounds they create to communicate over hundreds and hundreds of miles / km with each other. I will source that info if you'd like.

I think the game limits the hydrophone's range to much less than that to conserve resources ("optimization" some have complained about) and make the game more challenging.
IMO we don't have any weapons we can fire and successfully hit the target with over about 10 miles (16km) so it's really not necessary for it to have historically accurate range. It would be useful if we could track and intercept targets from 50 miles away but that would probably cause the game's system requirements to be a lot higher than they are.

[Jack Schitt]

Originally posted by Ruby:

HI Kargul85,

Look at the tooltip and/or the info of the hydrophone. There you will find that the hydrophone will hear > 100 km when the station manned by officers and sailors.

Within the displayed hydrophone radius is the officer able to identify the detected noises.

Cheers Ruby

This raises the question as to why the range circle only indicates it's detecting things within around 8km. If it's going > 100km why is the range thing as small as it is? Resource optimization?

[Ruby]

Originally posted by Jack Schitt:

Originally posted by Google Search Result:

50 miles
By the end of World War II, German hydrophone operators could detect enemy surface ships at ranges of as much as 50 miles. Sonar was a mixed blessing for submarines. It could be used to give an accurate range and bearing on a surface target, but the emitter also provided a bearing for the enemy's A/S forces.

Citation Source[fleetsubmarine.com]

Sound travels through water further than it does in air. Wales use the sounds they create to communicate over hundreds and hundreds of miles / km with each other. I will source that info if you'd like.

I think the game limits the hydrophone's range to much less than that to conserve resources ("optimization" some have complained about) and make the game more challenging.
IMO we don't have any weapons we can fire and successfully hit the target with over about 10 miles (16km) so it's really not necessary for it to have historically accurate range. It would be useful if we could track and intercept targets from 50 miles away but that would probably cause the game's system requirements to be a lot higher than they are.

Hi Jack,

Your listening officer reports far away noises. Check the tooltip and the station info to see how far he can listen. Only you could not hear it yourself. But as announced in the Dev Diary, the hydrophone has been reworked.

This raises the question as to why the range circle only indicates it's detecting things within around 8km. If it's going > 100km why is the range thing as small as it is? Resource optimization?

This has nothing to do with resources. Within the circles he can create a target solution. Slowly, but he can.

Cheers Ruby

[Jack Schitt]

Aha! Thank you, Ruby!

[Maste76]

Wird es mit B129 möglich sein, auch manuell (Egoperspektive), mit dem Hydrophon eine Ziellösung zu machen.

[Sam Wise]

Im pick up convoys at approx 60 Nmi range.

[ждун]

It should be noted that the game distinquishes between direct and estimated accoustic contacts.

Large groups such as convois or task forces can be picked up from more then 100km range. But you don't get the precise position, just a rough estimation in ceratain area. You cannot detect single ships from that range, only groups of ships.

And then there is direct accoustic range, its the light blue circle on the map. Inside that circle youre picking up each single ship at its very accurate position. It will also trigger the alarm. The direct detection range may vary and depends on many things. Especially on the amount of noise youre producing yourself. The louder you operate (fast speed, loading torpedoes, using compressor etc...) the shorter is your direct detection range. When full stopped and being as quite as possible it can be about 8 kilometers or more.

Now to real things:
In reality there was no such thing as direct accoustic contact, It is impossible to pick up precise position of a ship using just passive hydrophone. You get only the bearing, not the distance. The distance can be just estimated, however an experienced operator can estimate it quite well with a small error margin.

In reality experienced operator could pick up sounds of convois at long distances over 100km, but it doesn't mean that you can say the hydrophones range should be like that. From 100km you can barely hear something. You can just say there is some large group in that rough direction very far away. Not much more can be established from that distance.

The game tries to simulate that by distinquishing between distant group contacts (propeller noise) and direct detection range. And i find it a very good solution. However in reality there would be no hard detection circle. The transition from uncertain -> certain would be smooth. The closer it gets the the more reliable is the data.

Maybe from 50km or something the operator would already be able to say whether this is a convoi or a task force. From 20km he will probably already be able to estimate the number of warships and merchants in the group and figure out whether there are any capital warships in it and how many. From 10km he would probably start distinquishing each individual ship from each other etc...