KILO vs KILO improved with LWAMI

[OKO]

Hi all
well, I wanted to tell about it for some times, but it's not a real problem at this time for gameplay, maybe usefull for this instead ...
But I feel like I must say it :
in LWAMI mod (I don't know for stock, I didn't checked as I always use LWAMI), the KILO improved is much more quieter than the KILO.
the KILO make 266% of the sound level of the KILO at every speeds.

I hardly believe that the KILO could be 2,6 times louder than the imporved version at every speed.
real values are more probably around X 1.3 to X 1.8

this cause the KILO to be quite easily detectable by the improved KILO when the KILO won't be able to counter detect (with passive) except at VERY close range.
Improved KILO is virtually indetectable for the KILO, when the improved KILO will easily detect the KILO at range from 10 to 15 miles.

Improved KILO make the same noise at 12 knts than the KILO at 4 knts, and KILO imp make the same noise at 19 knts (close to max speed) than the KILO at 11 knts (combat speed).
This can be true IRL, of course.

But I have to admit, this give you 2 very different ships, and that's quite nice for scenarios.
Maybe, anyway, a reduction of the sound gap beetween these 2 platforms could be made.
evry 3 dB, there is twice the sound level.
So, instead of X 2.6, near 3 times the sound level, maybe KILO could be change to be only 3 dB more (instead of 5) compared to the improved version ?
This time the KILO will be only twice louder than the improved.
I think actual values are quite to big at this time, I could chek it in a scenario where a HAN and 2 chinese KILO KLUB (so improved)escort a XIA, with 2 russian kilo attacking the XIA.
Russian never detect chinese KLUB with passive, when chinese always detect both 2 russians standard KILO with passive.
quite nice for the scenario, but maybe a bit far from realism.

what do you think about ?

Hm. This difference really seems not to be true. But the qustion is - should we increase the stealth of Kilo, or to decrease the stealth of Kilo imp? :)

[LuftWolf]

The Kilo and Kilo Imp are 5 PSL away from each other.

At 0 kts, the Kilo is 60 PSL, a bit louder than a Akula Imp I (59), and the Kilo Imp is 55 PSL, which is equivalent to the SeaWolf (the SeaWolf stays quieter at speed than the Kilo Imp of course).

The difference between the Kilo Imp and the Kilo is roughly the difference between the Akula II and the standard non-playable Akula I.

These figures come from real world data that Amizaur compiled from Russian data and projections, so they more or less are what they are.

Of all the things in the mod, I think I am most comfortable with the relative platforms sound levels, since SO much work had been done on it before I became involved by jsteed, finiteless, and Amizaur. I have seen their working graphs and they are quite impressive.

[OKO]

so ... the KILO make 266% of the noise level of the improved KILO ...
only 1/3 of the KILO sound level, with the improved KILO
Still looks quite strange to me ...
and this make huge difference in game, of course.

[Kazuaki Shimazaki II]

so ... the KILO make 266% of the noise level of the improved KILO ...
only 1/3 of the KILO sound level, with the improved KILO
Still looks quite strange to me ...
and this make huge difference in game, of course.

Is 5 PSL really 5dB difference, or 10? I ask this because IIRC the estimated noise levels of those subs in dB are very roughly 2x the PSL value - the Akula is about 115-130dB (dependent on variant and source data) for instance IIRC.

Anyway, with the sub technology having advanced something like 15 years b/w the standard Kilo and the 636, I'm not exactly surprised even if the 636 is indeed 10dB quieter. Supposedly the 688I is also 10 times quieter (10dB) than the original 688, which corresponds roughly to the current PSL in the game (PSL*2=approx dB)

[LuftWolf]

It is a compressed scale.

Generally speaking, 1 PSL= 2 db.

[Kazuaki Shimazaki II]

'bout what I thought. IIRC, the 636 is supposed to be about 50% quieter than the 877EKM, which presumably in turn had some significant quieting improvements over the oldest 877 models so a 10dB difference overall sounds fair.

[RedDevilCG]

You sure about that? 10dB means that that the 636 is 100x quiter than the 877.

For comparison purposes, if one sound source is 50% quiter than another, it is 3dB quiter, or louder depending on which way your are comparing (quite to loud / loud to quiet).

Lets say that you do a further 50% reduction on the first one. You once again reduce it by a further 3dB.

So a 50% reduction, and another 50% reduction? A total savings of 6dB.

Cheers.

[Kazuaki Shimazaki II]

You sure about that? 10dB means that that the 636 is 100x quiter than the 877.

That's 20dB. 3dB is 2x, 5dB is about 3x, 7dB is very roughly 5x IIRC and 10dB is a mere 10x, 13dB is 20x and so on.

[OKO]

LOL
this thread become a lesson about dB :cool:

The only simple thing I know about dB is : each more 3dB, you have twice the sound level
So, 10 dB is a bit more than 10 times the sound level

But in DW, it's NOT 10 dB beetween KILO and Improved, it's 5 dB (with LWAMI) just take a look at the graphical chart.

So the Improved KILO, who is always 5dB less than KILO at same speeds, is around 3 times quieter.

But what does it mean in the game :
you can detect a KILO with another KILO at ~12 miles, but you won't be able to see any improved KILO on passive sonars of a KILO.

I have one question for Luftwolf : are the conformal and cylindrical the same on KILO and on improved KILO in DW ?
I ask this because improved KILO are supposed to have improved sonar suit IRL.

[Kazuaki Shimazaki II]

The only simple thing I know about dB is : each more 3dB, you have twice the sound level
So, 10 dB is a bit more than 10 times the sound level

Actually, 3dB=2x is the approximation and 10dB=10x is the exact version. What most people forget with decibels is that it is really a variant of the bel, which is a logarithmic measure of intensity. The "deci" is a prefix which means 0.1. 1 bel (10 decibels) therefore means 10^1=10x the intensity of 0 bel, 2 bel (20 decibals) is 10^2=100x the intensity of 0 bel.

But in DW, it's NOT 10 dB beetween KILO and Improved, it's 5 dB (with LWAMI) just take a look at the graphical chart.

No, the difference is 5 PSL. I remember seeing those charts and they are measured in the game unit PSL. Each PSL = roughly 2dB, as LW confirmed up there, so it is 10dB = 1 bel = 1 order of magnitude = 10 times quieter.

But what does it mean in the game :
you can detect a KILO with another KILO at ~12 miles, but you won't be able to see any improved KILO on passive sonars of a KILO.

The Kilo's passive sonar was never very good (small, cylindrical...) - my question would be whether it is appropriate for a KILO to detect another (presumably slow moving) Kilo at 12 miles.

I have one question for Luftwolf : are the conformal and cylindrical the same on KILO and on improved KILO in DW ?
I ask this because improved KILO are supposed to have improved sonar suit IRL.

The upgrade AFAIK is mostly software and processing. You can check that one for yourself by downloading DWEdit and actually taking a look see in the database - get it at SubGurus. Or maybe I'd check for you and let you know after my computer finishes its current defrag.

Yes, all Kilos have a:
MGK-400 Active Sonar
generic Active Intercept
MGK-400PBB
MRM-25EM ESM
Visual
MRK-50 radar
MGK-400 PNB

OK, if you wanna do the switch, here are some recommendations (http://66.102.7.104/search?q=cache:C5aCstRwzLIJ:www.steel.sakura.ne.jp/ensub/contents/ru/data/ru_data_636.html++site:www.steel.sakura.ne.jp+EnSu b&hl=en)

Yes, I know the above site is in Japanese and it unfortunately went out of business, but it is the only one I have. Translating the important bit, the 636 is supposed to be twice as quiet as the 877EKM (which may be a export version but it is still a hell of a lot newer than the baseline Kilo). The sonar is 2.5 times as sensitive. there is already an unused Improved Kilo sonar which has no changes over the original, so change Nrd detection on that sensor from -13 now to -15, and make the new Kilos use it.

[LuftWolf]

I'm not so sure about detecting a kilo at 12nm. :hmm:

It must have had a diesel on or been cavitating, that's the only way I see that happening to be honest.

I was originally going to make separate sonars for the Kilo and Kilo Imp but then stopped because of a lack of a way to reasonably estimate the differences in the sonars, as well as the fact that while it is rumored they are upgraded, the MK-400 (I think) is listed for both in any source I came across.

I left them the same because it is reasonable to me that the standard Kilos' sonar would be upgraded to the 636 standard by nations fielding both Kilo Imp and 877's.

[Kazuaki Shimazaki II]

I was originally going to make separate sonars for the Kilo and Kilo Imp but then stopped because of a lack of a way to reasonably estimate the differences in the sonars, as well as the fact that while it is rumored they are upgraded, the MK-400 (I think) is listed for both in any source I came across.

Early Soviet nukes used the MGK-200. By the time of the Victors they were to the -300, which they claim (http://warfare.ru/?catid=332&linkid=2085) is superior to the BQQ-2. Then there is the MGK-400, which is used in the Kilos. Some sources claim the Victor-III used the MGK-400 as well, while others claim the MGK-500 series. I suppose they might have used the -400 for a few of the early ones until the -500s (Typhoons, Delta IVs, Sierra, Akula, Oscar) came in.

The fire control system in that one is apparently a MVU-110EM (http://web.archive.org/web/20030303155002/http://www.steel.sakura.ne.jp/ensub/contents/ru/data/ru_data_877.html), which tracks 2 targets automatically, which is roughly what you see in the game Kilo.

The newer ones (EKM, 636) use the -400EM. It is the same size, but apparently includes better tranducers and all new computers and displays that among other things can track 12 targets automatically. The only info I have says it is about 2.5 times the sensitivity (see previous post). So it is not necessarily an easy upgrade for user nations - let alone Russia, who is lucky to keep its subs running.

BTW, if I do want to make a differentiation and assume the EM is 2.5 times more sensitive (there's no way to get it to track more targets short of massive code hacking) than the base version, am I correct to set the Nrd difference to "2".

[LuftWolf]

It is the same size, but apparently includes better tranducers and all new computers and displays that among other things can track 12 targets automatically.

Then it sounds like the perfect thing to be fitted onto the 877's. :)

Seriously, the standard Kilo is already a pretty juicy target in LWAMI (behaving like a 25 year old sub which it is...), I don't really want to make it deaf as well. :know:

[Kazuaki Shimazaki II]

Seriously, the standard Kilo is already a pretty juicy target in LWAMI (behaving like a 25 year old sub which it is...), I don't really want to make it deaf as well. :know:

That's why maybe we should improve the newer Kilo's sonar by 2 points rather than degrading the older Kilo's sonar by 2 points :D

In fact, I already improved the bow and tails of Gepard by 2 points on my own database (it now has the theoretical sensitivity of the 688I, still not as good as Seawolf's sonar of course, washout improved but still inferior to Yanks, and the waterfall is simply a better display than the SSAZ) - I'd have to remember to get a "stock" LWAMI copy before going multiplayer.

[LuftWolf]

That's why maybe we should improve the newer Kilo's sonar by 2 points rather than degrading the older Kilo's sonar by 2 points

Well that's an option.

I have to look at all the passive sensitivies as a group as the community gains more experience and we get some reports from 1.03+3.00 Full versions.

For now, I'm pretty happy with how things stand relatively as those settings have held up well for 5+ versions now. :)

[RedDevilCG]

Woops, I meant 10X not 100X.

I too fiddled with the Akula-II's, making the washout for the towed array "Pelamida" be 17knts. It just seams too wierd to me that the towed array washes out before the sphere array (15knts).

[OKO]

Very interesting post about KILO's sonars, thanks guys !


The Kilo's passive sonar was never very good (small, cylindrical...) - my question would be whether it is appropriate for a KILO to detect another (presumably slow moving) Kilo at 12 miles.

I'm not so sure about detecting a kilo at 12nm.

It must have had a diesel on or been cavitating, that's the only way I see that happening to be honest

well, actually, I based a scenario on this (didn't already made the briefing ...).
One XIA is escorted by a HAN and 2 chinese KLUB KILO (so ... improved hull).
2 Russian KILOs (standard, the louder one) have to sink the HAN before he reach a datum.
The chineses improved mission is to help the HAN to reach the datum, by frightening or killing the 2 russian KILOs.

On this mission, you must hold weapon until you receive the weapon free message for your side.
You receive the weapon free when :

1) any chinese KILO detect a russian KILO

2) any russian KILO detect the XIA or the HAN : not only the XIA to make some confusion at ID the right target, because the goal is to sink the XIA, and sinking the HAN won't give any credits on mission briefing.

3) the other side has already receive the weapon free 6 minutes ago.

For 1) et 2), you will receive a weapon free only 6 minutes after assigning a tracker on the target : this is to confuse a bit the players, to avoid they immediatly know the just assigned tracker is the target.
and 3) is to give a weapon free on both side, even if one side didn't detected an enemy target.

And on this mission, it's not always the HAN (the louder ship) who is detected first !
it's 50/50 the HAN or a russian KILO who is first detected.
I had detection until 15 miles (on manned KILO at 12 knts max, not cavitating), with the help of CZ, I need to mention it.

But on this mission, you will always be able to find the russian KILO with chinese KLUB passive sonars (conformal of course) at some times during the mission, when you won't be able at all to see any chinese KLUB on the russian KILO passive sonars.
Best detection time is 6 minutes after mission start (but certainly du to a specific convergence, and happen only once in ~6 MP games, usual detection time is 20 to 40 minutes).

try the mission in both side (every plateform is scripted to play this solo also), you could see what I mean =>
http://okof4.free.fr/missions/DW/MP4_Diesel_slick_b1.0.mu


speed and depth of subs are randomly generated (4 possible speed and 3 possible and specific depth for HAN and XIA, so you must search at every depth).

Here you will see it can be possible to make distant detection ( ... say medium range detection) on a standard KILO with a KILO sonar.
The mission is based on this, indeed

As I said in my first post, this is not bad at all for gameplay, on the opposite it's fine.
My question was : Is it realistic to have such a gap beetween these 2 versions.

You convince me it is, gents.

Also hope to play this one with you soon, very funny match in MP !
Even in solo it's quite a hard fight.

[TLAM Strike]

Even in solo it's quite a hard fight. Really? I took out all four PLAN submarines while playing as the Russians. :o

The Nucs got killed by SUBROCS and Kilos by one well placed two USET-80 spread. The PLAN did manage to kill the other Russian Kilo.

[OKO]

I hope, you waited for the weapon free message ! (you don't mention this)
If you did so, what was the first ennemy platform you detected to have this weapon free message ?

can you explain also how you found the chinese KLUB ???
with active I presume, or you didn't play it with 1.03 & LWAMI 3.00 (he is just impossible to find on NB conformal like this).

Of course, I don't know what happen with stock DW for this mission, as all my MP mission (...and solo mission also, even the KILO campaign I just started)

but in fact, this mission, played solo, is harder in defense ... if using 1.03 + 3.00 of course.

This mission was made for MP purpose, but I tested it about 10 times in solo, and never saw even once a KLUB when I attacked with russians.

[TLAM Strike]

I hope, you waited for the weapon free message ! (you don't mention this) Yep.


If you did so, what was the first ennemy platform you detected to have this weapon free message ? We detected the Han and Xia 1st. the Russians got WF 1st. (I think)

can you explain also how you found the chinese KLUB ???
with active I presume, or you didn't play it with 1.03 & LWAMI 3.00 (he is just impossible to find on NB conformal like this). I was playing 1.01 LWAMI 2.02. 1.03b has this CTD bug with torpedoes that drives me insane! But I nailed the Kilo when they speeded up and there was another kilo right next to him and boom; two birds with one stone as they say.

[OKO]

ha ... I understand better.
With the 1.03 , you have the layer effect that you don't have with previous version

I scripted the HAN and the XIA to choose specific depth (3 differents) and specific speed (4 differents)
with 1.03, this mean you have to work MUCH HARDER to find them above, in or under the layer.
This makes the mission really much more difficult from previous versions of patch.
say nothing to compare ...

if you test it with 1.03 + 3.00 , this won't be the same mission at all.
and this will be really harder to detect XIA or HAN, even if the HAN is much easier to find (noisy sub)
HAN is here to confuse you on the right target, and do a very nice job on this matter.

With this (1.03 + 3.00) you won't detect KLUB at all, I can assure you or only if they are very close to you, or if you use the active (bad choice on this mission for attackers, of course)

[OKO]

1.03b has this CTD bug with torpedoes that drives me insane!
huh ?
can you give me a link about this, please, because I don't have this problem here, and didn't heard about it.
thanks TLAM :)

[TLAM Strike]

1.03b has this CTD bug with torpedoes that drives me insane!
huh ?
can you give me a link about this, please, because I don't have this problem here, and didn't heard about it.
thanks TLAM :) http://www.sonalystscombatsims.com/phpBB/viewtopic.php?t=193

I recently discovered it goes beyond towed decoys and affects MK48s too.

[XabbaRus]

I had that CTD too...Nixie out, and two torps coming at me.