China’s Noisy Subs Get Busier — And Easier to Track

[gambit]

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Gambit, how are any of the radar pics you posted like an acoustic waterfall ?? Any of them?? See my pic. I see you are trying to BS your way out of this corner.

All the pics you posted look just like the standard radar everybody thinks of from old movies to the doppler radar on the Weather Channel. They even look like the "sonar" that Hollywood uses incorrectly in bad submarine movies and even some video games (Crysis or COD Modern Warfare series got it wrong too).

I'll leave that question for you hanging....

Why are you avoiding the 'A-scope', which is the original and genuinely the true radar scope? If anything that is hanging, it is YOU and your credibility. Explain the A-scope.

[Aramsogo]

Why are you avoiding the 'A-scope', which is the original and genuinely the true radar scope? If anything that is hanging, it is YOU and your credibility. Explain the A-scope.

Because your A-scope isn't a waterfall either, it's closer to a mass spectrometer (look that up).

Here's a mass spect. Nothing like a sonar display and basically like your A-Scope.

[Aramsogo]

Gambit, I'll make this easier for you. Modern subs have active noise cancellation (conceptually like $35 headphones Made in China). When it's turned on, noise is lowered. When it's off, noise is higher.

[gambit]

Because your A-scope isn't a waterfall either, it's closer to a mass spectrometer (look that up).

Here's a mass spect. Nothing like a sonar display and basically like your A-Scope.

You failed. You get an 'F'.

The radar A-scope is a SIMPLIFIED display of a target return based upon the most prominent property of said target -- echo.

The sonar 'waterfall' scope is the same thing -- a SIMPLIFIED display of an underwater target based upon the most prominent property of said target -- echo.

Both methods of VISUALIZATION of display does not negate what they are. The 'waterfall' effect is only the result of adding time as a factor in the 'vertical' view whereas time does not figure in the radar A-scope. In fact, if the sonar echo is analyzed and displayed in freq and sound pressure level (SPL) or amplitude, the visualization of the echo would like practically identical to the radar A-scope, which include amplitude.

[hohohoho]

Why are you avoiding the 'A-scope', which is the original and genuinely the true radar scope? If anything that is hanging, it is YOU and your credibility. Explain the A-scope.

they keep avoiding.. they know only to misrepresent and fabricate.

[gambit]

Gambit, I'll make this easier for you. Modern subs have active noise cancellation (conceptually like $35 headphones Made in China). When it's turned on, noise is lowered. When it's off, noise is higher.

That is another method of masking, except that it is more like SUPPRESSION of internally generated noise. What you falsely claimed, or at least implied, here is that the sub generated an alternate signature that has all the ingredients of what a non-natural noise signature would appear to a detector. Those ingredients would include things like prop noise and other contributors like skin friction or mechanical pumps and so on. Those ingredients would be artificially generated and propagated. This is far beyond generating a field of popping bubbles. So where are your sources to support your claim?

[Aramsogo]

Spin. Just look at the pics you posted and the one I posted.

They add a time dimension to Doppler radar too on the Weather Channel. You know what I'm talking about. The properties of water does not equal air. You can't fit a 50,000 watt radio station inside a fighter plane, but every attack sub has one in the form of active sonar.

You failed. You get an 'F'.

The radar A-scope is a SIMPLIFIED display of a target return based upon the most prominent property of said target -- echo.

The sonar 'waterfall' scope is the same thing -- a SIMPLIFIED display of an underwater target based upon the most prominent property of said target -- echo.

Both methods of VISUALIZATION of display does not negate what they are. The 'waterfall' effect is only the result of adding time as a factor in the 'vertical' view whereas time does not figure in the radar A-scope. In fact, if the sonar echo is analyzed and displayed in freq and sound pressure level (SPL) or amplitude, the visualization of the echo would like practically identical to the radar A-scope, which include amplitude.

[Aramsogo]

That is another method of masking, except that it is more like SUPPRESSION of internally generated noise. What you falsely claimed, or at least implied, here is that the sub generated an alternate signature that has all the ingredients of what a non-natural noise signature would appear to a detector. Those ingredients would include things like prop noise and other contributors like skin friction or mechanical pumps and so on. Those ingredients would be artificially generated and propagated. This is far beyond generating a field of popping bubbles. So where are your sources to support your claim?

Active noise cancellation is but one example. Even how fast they turn the sub or the rpm of the propellers effects this acoustic signature. During peace time, they don't have to run silent. It is far easier to run noisy than run silent. Like I said, everything on a modern sub is damped and runs like silk for a reason. As a Chinese member, I just don't buy the Wired magazine analysis that Chinese subs have gotten noisier and easier to track in the last 10 years. It doesn't even make common sense given how much China has progressed technologically in the last ten years.

Let me ask you a question Gambit and I'm sure you'll give me an honest answer because you are an honorable person I assume. If Chinese FHM / Maxim wrote an article saying Virginia-Class is noisier and easier to track than Los Angeles-Class, would you say bullsh!t ?? How come these common sense standards don't apply in this case ??

[below_freezing]

And this is where you are SPECTACULARLY wrong. In EM propagation, signals are affected by atmospheric phenomena like 'hydrometeors' such as rain or snow or fog. The closer the wavelength to the physical dimensions of the individual bodies of these phenomena the greater the effects. My advice to you: Leave this subject until you have a real job in a related field.

how many times do fighters go to war in altitudes and zones of rain, snow, fog? seriously?

and how is "rain, snow, fog" something that is related to "temperature, solute concentration, depth"?

[SinoChallenger]

I think the 100% electrified propulsion of the Type 095 gonna boast its overall performance against other SSNs.

All the future PLAN warships gonna be 100% electrified propulsion.

Wait a minute. Don't you mean all nuclear warships will be electrified (i.e. no longer use noisy steam)? If not, what about diesel engines and gas turbines? Will they be all electrified? How?

IMO, the Type-095SSN will still lack when compared to the latest USS SSNs but it will be much better than the late Los Angelese class.

However, weapons such as the J-20 and Type-052 Destroyer will be virtually identical to what the US has produced in the last decade.

China is nearly there and in the next decade should be able to match the US toe-to-toe in any field, civilian or military.

I agree with your post and also want to emphasize that in fighter jets J-20 is far closer to world class standards than China's future air defense destroyer Type 052D is to world class standards. J-20 was publicly revealed in the beginning of this year but obviously must have done first flight before that even (probably with Russian engines) in 2010. Type 52D has not yet begun construction, and I don't think the first one will even launch until 2013-2014. By then J-20 will definitely have entered service with PLAAF.

[Alpery]

It does not.


Actually, it is YOU who do not have that clue.

Masking is not the same thing as silencing. Surface ships on the move cannot suppress their noise, however, they can mask their signatures. Both signatures can have the same noise level with one signature the true one belonging to the ship.

On the other hand, subs belongs in a different issue. A sub tries to be as silent as possible at all times. No masking. If a sub cannot be detected, then it does not matter its signature. But if a sub continues to produce masking noises that are greater than its true signature, it can be tracked, so what good is it then? You can try to argue that producing a louder but false signature during peace time to deceive potential adversary is a 'valid' tactic but then it begs the question of why bother to design subs to be as silent as possible in the first place?

This lead us back to the issue of being silent. If you cannot produce a sub that is superior to the enemy, then it does not matter if you mask your true signature or not. As long as you are on the move, trying to mask your true signature is pointless, you will be tracked with that false signature AS IF it is your true one. Turning it off does what? Nothing. Your true signature is just as loud. So what if the enemy detect a supposedly 'new' signature? Do you think he cannot deduce the fact that the new signature is in the same position as the old and most likely that mean you? If the new signature does not match known 'friendlies' what does that make the new signature? How about you being a 'foe'? What good was your masking then?

Another clue for you: Radar detection and sonar detection are 99.999% philosophically identical. EEs from one discipline can transition to the other with little trouble. In radar detection, the F-22 flies with enhancers primarily to assist air traffic controllers with the secondary benefit of masking its true RCS. Underwater, there are no traffic controllers, so even if the sub's masking signature is as low noise level as the true, if the false is finally detected, the true will eventually be figured out and that deduction will be without your knowledge, in other words, if the enemy figured out your mask, he will do whatever he can to convince you of your perceived advantage to keep you in the dark of his advantage.

This is why your friend's claim to have worked on sonar is getting more dubious upon closer examination of his statement that a sub MUST employ masking techniques.

thanks....but..
l can not understood something...
ATC use secondary radar and aircraft use transponder...so F-22 no needs RCS enhancer
if F-22 tactically use it, than submarines sould use same tactic....

or oppositely, show your technical ability that keep the peace...

am l wrong?

[bdslph]

the old version subs are very noisy of China but not the Latest one of China

[IND151]

its obvious that Chinese subs are noisy

there is a source which shows that china until recently ( till 2000 ) didn't gave full attention to PLAN

but now china is planning expansion of PLAN and will do best to solve noise problem

[gambit]

Active noise cancellation is but one example. Even how fast they turn the sub or the rpm of the propellers effects this acoustic signature.

This has nothing to do with the fact that while SUPPRESSION is a valid member of the 'masking' category, suppression does not give the enemy a 'false' sonar signature. What you said is nothing more than generalizations that everyone knows.

During peace time, they don't have to run silent. It is far easier to run noisy than run silent.

This is stupid. If you build a boat than can be more silent than anyone can detect, why would you want to run 'noisy' in the first place? Just run silent so no one will know where you are. This is why I doubt what you said about yourself.

Like I said, everything on a modern sub is damped and runs like silk for a reason. As a Chinese member, I just don't buy the Wired magazine analysis that Chinese subs have gotten noisier and easier to track in the last 10 years. It doesn't even make common sense given how much China has progressed technologically in the last ten years.

Did the Wired article really said that? Let us take a look at the relevant passages...

China's Noisy Subs Get Busier -- And Easier to Track | Danger Room | Wired.com

China’s Noisy Subs Get Busier — And Easier to Track

The article's title said nothing about 'noisier', just 'busier'.

and, the roughly 60 submarines in the People’s Liberation Army Navy (PLAN) fleet are spending more and more time on combat-ready patrols — signaling China’s increasing naval competence and growing seriousness about influencing the western Pacific Ocean.

This has nothing about China's subs 'getting noisier', only that they have been spending more time at sea.

On the other hand, the flurry of undersea activity gives American forces more opportunities to tail and examine Chinese subs. And U.S. analysts discovered a silver lining in the gathering strategic storm clouds. Chinese submarines are a hell of a lot noisier than anyone expected. The sound you hear is the Pacific balance of power tipping in Washington’s favor.

This has nothing about China's subs 'getting noisier', only that now that there are more of them at sea, analysis found that they are noisier than expected. There is a difference between expectation versus known.

As recently as 2007, China’s diesel-powered subs and a handful of nuclear-propelled models managed just a few patrols per year, combined. Two years before that, none of Beijing’s undersea boats went on patrol. For years, the majority of PLAN submarines remained tied up at naval bases, sidelined by mechanical problems and a shortage of adequately trained crews.

As long as the PLAN’s submarines were idle, the U.S. Navy’s spy planes, surveillance ships and snooping subs had few opportunities to assess China’s undersea capabilities — and, most importantly, how much noise the Chinese generate while submerged and moving. Navies can use passive sonars to track submarines by the sounds they make. The louder a vessel, the easier it is to detect. And destroy.

What this mean is that the lack of China's subs AT SEA mean the lack of knowledge about how loud or silent the Chinese subs are. The last highlighted statement is a generalization, as in 'a vessel', a generic, not a specific, as in 'a Chinese sub'.

With little information to go on, American intelligence officials had to guess. In cases like that, “you guess conservatively,”

Right...So to guess conservatively mean you give the benefit of the doubt, as in expecting China's subs to be 'silent' enough to make it difficult to detect, but then because of an upsurge in PLAN sub activities, US subs found out that PLAN subs are not as quiet as what was 'conservatively' guessed.

Now Chinese subs are patrolling more frequently. “Within the last year or two the Chinese have begun to deploy diesel boats more frequently into places like the Philippine Sea,” the analyst reveals. More and better data is flowing in from U.S. forces. With that data, the Navy conducted a fresh assessment of PLAN submarines. The unnamed analyst attended a classified briefing based on the assessment.

Right...So once again, we are not saying that Chinese subs have been getting 'noisier' from a known standard, only that they are 'noisier' than what we originally guessed. More data support those new estimations.

But the Navy’s just discovered that China’s homemade subs are even louder than 20-year-old Russian boats.

The known standard here is not Chinese but Russian. So based upon analysis of INCREASED Chinese sub activities, we found that Chinese subs are inferior to Russian subs.

The U.S. Navy had a comfortable technological lead over the PLAN even before the increased Chinese sub activity fueled the recent intelligence coup. Now that lead has gotten even wider. And noisier.

The last highlighted words are more rhetorical than it is technical. The 'noisier' does not mean intensity PER unit, as in per Chinese sub, but rather of overall volume, as in more Chinese sub activities that contributed more noise into the seas.

Your comment about being Chinese mean you cannot believe anything that is critical of China, no matter how much of that criticism is based upon science, reinforced the belief that the Chinese boys here are a bunch of racists.

Let me ask you a question Gambit and I'm sure you'll give me an honest answer because you are an honorable person I assume. If Chinese FHM / Maxim wrote an article saying Virginia-Class is noisier and easier to track than Los Angeles-Class, would you say bullsh!t ?? How come these common sense standards don't apply in this case ??

If I say BS, it will be because US subs have been around the world much more than Chinese subs. Heck, probably much more than the entire PLAN itself. That is the problem for your argument, in order for that hypothetical Chinese article to have any credibility, the PLAN must be active in 'blue water' naval experience, because that is where US subs usually are, and that the PLAN must have a reasonably accurate and voluminous library of US sub signatures, which we know is absurd because the PLAN is not a 'blue water' navy. More like a US Coast Guard equivalent. You speak of common sense, more like you do not have any in this debate.

Spin.

The only thing I see spinning here is your credibility regarding your claim to have worked in sonar for a US defense contractor. If you cannot read an article intended for the laymen and understand what it mean, why should we take you at your word that you actually worked in the field relevant to the article? Your fellow Chinese conscript rejects will swallow anything you say. We expect no less from compatriot racists. But the rest of us know better...

[gambit]

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how many times do fighters go to war in altitudes and zones of rain, snow, fog? seriously?

May be not Chinese fighters, but ours do and have.

and how is "rain, snow, fog" something that is related to "temperature, solute concentration, depth"?

Each group affect the medium of detection. The point here is that if an EE from one discipline can understand that what he is seeing is data derived from a hardware, he can learn to process that data regardless of the source. No one is saying an EE from radar is going to see low freqs underwater the same as ghz bands in the air. But if he recognize that sonar target data is on the lower scaling than radar target data, he can adapt to his new job. Sonar deals with Doppler. Are you saying radar does not?