Hydrophone is too sensitive and accurate

[snakeskip]

Started a new campaign with 100% realism and controlling captain only. I thought having no map contacts would make chasing freighters more challenging. Unfortunately it's not. I've already sank three ships while spending no torpedoes and only about 15% of diesel. At this rate I'll sink more tons during my first patrol than what some quite successful captains ever did in real life.

What I've learned from reading a couple of books is that finding targets was often frustratingly difficult and sinking a ship was always a celebrated accomplishment.

I think the hydrophone is simply too sensitive and accurate. Locating single freighters from over 50 kilometers away and giving exact bearing of targets feels OP. Even without knowing the actual distance of the contact, I can make an educated initial guess of 50 km and start chasing by guessing the target port of the freighter.

According to some sources the range for detecting single ships should be about 20 kilometers. I think that would make the game a lot more challenging.

Perhaps there should be a setting for hydrophone range and accuracy.

[cato]

Yeah agree with all that. One house rule I use is I ignore all single ship sound contacts over 30 km's and convoy contacts over 60 k'ms. Its a crude way of making it more realistic but it has the desired affect.

[snakeskip]

At this point I don't even get the distance of the contacts. Just the bearing. Perhaps the radio man is too inexperienced or there's a difficulty setting for this. It doesn't matter. If I don't yet see the smoke yet, can always assume it's about 50 kilometers away at the time of the first contact. It's never too far from the truth.

[DECAFBAD]

If it wasn't for the perfect hydrophone, you'd spend weeks searching for a target. You'd run out of fuel before running out of torpedoes.
That is a different kind of game, and such a change does not belong in vanilla with all the people who are having a great time with the game balanced as it is. It belongs in a mod.

[er.tz]

If your hydrophone wasn't picking up ships, there was another submarine that was, and it would call the others. Being divided by zones, the control area was large enough to fish.

I believe that the difference in enemy casualties between a patrol in reality and in the game (in the early and central part of the war, later years enemy sunks was not common and submarine´s survival rate was very low), besides the game options and installed mods that affect them a lot, was due to the higher percentages of torpedo failures (the Historical Torpedo Failures mod partly addresses this) and that people generally fear for their lives and those under their command, which isn’t the case from the comfort of home. Risky maneuvers are taken constantly that wouldn't be taken in reality.

If we simulate the fear of losing your life and that of your crew, it would lead us to imagine that most risky maneuvers are not carried out, thus reducing the submarine's firepower potential; perhaps 35% of torpedoes should not be used for that reason. If we combine that with mods like Torpedo Failures and others like Accurate Warships and Aircraft, or keep the periscope wet, the numbers of sunk ships come closer to historical figures of the first part of the war, If we look at the commander’s manual written by the BdU, there is a constant insistence on not letting objectives escape, to push the machine to sink them, to take risks until the last moment for a shot. This indicates that they were aware of the human factor and were willing to endanger their soldiers for a few sinkings, like all the high-ranking officers of the armies. In real life, high-ranking officials do not earn medals because their soldiers survive, but rather because the enemy does not.

It should be taken into account that, no matter how much of a simulator it is, or precisely because it is also a game, certain concessions must be made for it to be viable (such as accelerated time, for example) and others as well.

[snakeskip]

Originally posted by DECAFBAD:

If it wasn't for the perfect hydrophone, you'd spend weeks searching for a target. You'd run out of fuel before running out of torpedoes.

I don't think so. Having a range of 20 kilometers for single ships and up to 100 kilometers for convoys would still be very powerful.

(Those are suggested ranges in this article: https://en.wikipedia.org/wiki/Gruppenhorchger%C3%A4t)

Originally posted by DECAFBAD:

That is a different kind of game, and such a change does not belong in vanilla with all the people who are having a great time with the game balanced as it is. It belongs in a mod.

Having an option to tune the difficulty to arguably more realistic level wouldn't spoil anyone's enjoyment, would it? It wouldn't change anything for those who like the current balance.

The game already has a lot of options to make it more realistic. This just seems to be missing.

[DECAFBAD]

Originally posted by snakeskip:

Originally posted by DECAFBAD:

If it wasn't for the perfect hydrophone, you'd spend weeks searching for a target. You'd run out of fuel before running out of torpedoes.

I don't think so. Having a range of 20 kilometers for single ships and up to 100 kilometers for convoys would still be very powerful.

(Those are suggested ranges in this article: https://en.wikipedia.org/wiki/Gruppenhorchger%C3%A4t)

Those are the most optimistic numbers for Sonar performance of that era. Maybe there was one U-boat out of the thousand or so, that picked up a convoy at 100km. Of course those on board would never assume the sound bearing came from that far, since noone knew about the existence of convergence zones back then.
For sound bearings, a distance of 7-10km would be more realistic. That is what they got on trials, while actively trying to listen for known targets, i.e. the operator knew there was something around. When the operator scans at random without knowing that a target is near, the likelihood of detection plummets.

[snakeskip]

Originally posted by er.tz:

I believe that the difference in enemy casualties between a patrol in reality and in the game (in the early and central part of the war, later years enemy sunks was not common and submarine´s survival rate was very low), besides the game options and installed mods that affect them a lot, was due to the higher percentages of torpedo failures (the Historical Torpedo Failures mod partly addresses this) and that people generally fear for their lives and those under their command, which isn’t the case from the comfort of home. Risky maneuvers are taken constantly that wouldn't be taken in reality.

I agree. However, fear or torpedo failures is not a factor in very early war when chasing lone freighters. I'm not using torpedoes nor evading escorts yet. Just catching lone freighters and scuttling them when necessary. And it seems I could reach absurdly high sunk tonnages just doing that. (Using type VII now. Catching targets with Type II is definitely more challenging.)

One huge factor that is probably missing in the game is the difficulty of navigation and maneuvering in bad weather. That would be difficult to add to the game now as it is lacking navigation mechanics and extreme weather (AFAIK). If WW2 captains had GPS like we do in the game, they would've probably been way more successful.

[snakeskip]

Originally posted by DECAFBAD:

For sound bearings, a distance of 7-10km would be more realistic. That is what they got on trials, while actively trying to listen for known targets, i.e. the operator knew there was something around. When the operator scans at random without knowing that a target is near, the likelihood of detection plummets.

If that's a well established fact, then it would be sweet to have that kind of hydrophone performance level as an extreme option. I don't know how it would work with the half blind crew we have now, though. (When playing as the captain, it would be nice to be able to rely on some other eyes than my own. The captain has to sleep too.)

[er.tz]

The ranges of the hydrophones were military secrets, and I don’t think there is any real written documentation currently available. The data shown from measurements taken on captured submarines is not reliable either. Typically, it is said that the GHG can get independent vessels at 20 km and convoys at a standard of 100 km under optimal conditions. Water is actually a very good conductor of sound, better than air.

Water depth, temperature, and ambient noise can significantly affect sound reception at sea, as can the operator’s experience and keen hearing. Accurate data of real numbers would have to come from the operators of the hydrophones, and I get the impression that not everyone would say the same.

What is very unlikely is that they knew the exact bearing; it would have to be a range arc at a certain distance, just as there is a probable distances ranges.

[DECAFBAD]

Rössler's book on German Sonar is a good source. He quotes the results of the Balkon trials I mentioned above.
He also mentions an extreme range, but not a convoy, rather bombs. Dropped 100nm away being picked up by U47, scaring them thinking they were under attack.

But 100km for convoys would not be "optimal" condition. It would very much be an outlier. Maybe possible, but not the norm, and certainly not the expected performance. Not even these days.

[er.tz]

Originally posted by DECAFBAD:

Rössler's book on WW2 German hydrophones is a good source. He quotes the results of the Balkon trials I mentioned above.
He also mentions an extreme range, but not a convoy, rather bombs. Dropped 100nm away being picked up by U47, scaring them thinking they were under attack.

But 100km for convoys would not be "optimal" condition. It would very much be an outlier. Maybe possible, but not the norm, and certainly not the expected performance. Not even these days.

In uboat.net in an article about Underwater sound detector in WW1 and WW2 they say:

- for a destroyer- 9 to 18.5 km
- for a cargo ship- 6.5 to 14 km
- for a convoy- up to 93 km

[DECAFBAD]

uboat.net is the last resort when it comes to sources. There ought to be something better.

[SpaceBikerV]

Today i learned that hydrophones for single contacts have pathetic range….

That is not a fun gameplay experience, in my opinion. Being unable to hear anything for several days, only to encounter a neutral is kinda disappointing

[Feltan]

This whole topic seems ripe for a mod; "Realistic Sonar" with wider arcs of detection and shorter detection ranges. I would be simple to allow, say, 10% of contacts to be farther out due to unknown reasons (CZ's unknown in WWII).

[snakeskip]

Originally posted by er.tz:

In uboat.net in an article about Underwater sound detector in WW1 and WW2 they say:

- for a destroyer- 9 to 18.5 km
- for a cargo ship- 6.5 to 14 km
- for a convoy- up to 93 km

So a somewhat "realistic" but still quite simple and playable range limits could indeed be 20 km for single ships and 100 km for convoys. I tnink that would work as a realism option just like realistic torpedoes and other such option does now.