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

[below_freezing]

I worked at 9500 Godwin Drive in Manassas, VA. Use to be called IBM Federal System, now part of Lockheed Martin. They made every single sonar in the US sub fleet ever, except for Seawolf which was made by GE in Syracuse. Tom Clancy even visited to learn how sonar works.

As for saying passive sonar and airplane radar work on the same principles and the EE are interchangeable, I have never scene that in practice. Nor has that ever been explained to me that way. Sonar requires way more computer processing power, more than would be possible to fit on a fighter jet. Nor have I ever had someone from Lockheed transfer in from the division that makes fighter jets. Most of the techs were ex sonarman. This interchangeability is almost laughable. Air does not equal water. Simple logic should tell you that. If all you have is a hammer, everything looks like a nial. If you are an radar technician, then everything must look like radar??

Have you ever even been in a modern sub?? I haven't but I was surrounded by 20 men that have and the Navy did offer us tours but frankly I wasn't that interested (I wanted to do finance). The ride is as smooth as silk. Everything is damped. It's easy to generate noise and make a sub noisier.

You really don't know what you are talking about on this one.

I highly recommend you watch The Hunt for Red October to learn how sonar works. That movie is considered very accurate by sonarmen and yes the producers of that film did come to Manassas to see how sonar works too (Or so I was proudly told, it was before my time).

I would say, the sonar is much more difficult to work with due to things like salinity effects, depth, turbulence, shallow bottom effects, temperature effects, etc. while radar is just straight up EM, and air is basically vacuum to radar waves. Radar frequencies don't change based on ambient conditions too much, as temperature, salinity, height in atmosphere, etc. As you said, the processing power is not even close.

Even today, alot of sonar research is done in physics or math departments instead of any engineering because it is so complex you need the full knowledge of every branch of science.

 

[Aramsogo]

^^^^
Yup, if all you have is a hammer, everything looks like a nail. That's Mr. Gambit.

 

[S10]

I assume when gambit stated that sonar and radar are both similar, he was talking about wave physics. However, I fail to see the similarities beyond that point. Sonar utilizes sound the method of detection while radar utilizes radio wave. The environment they operate are vastly different, with different set of challenges for developers. To say that a radar technician would be able to jump right into sonar seems a bit of a stretch to me. While a person well versed in physics/electronics knowledge would have a much easier time adapting to the new trade than the average layman (i.e. me), to suggest such ease of field interchanability seems unreasonable.

 

[gpit]

Article has loop holes but here is my take on Sino Diesel Electric Subs. Modern Chinese AIP equipped subs are as deadly as any contemporary sub in the world. Yuan is already AIP quipped and has been updated thrice already. Qing is another story. As far as i know, Chinese have been working on AIP tech since early 90s and have invested heavily in this technology alone. The Sino Sterling counterpart has three flavors i.e. 80KW, 120-40 KW and goes upto 200 KW. Song, Yuan and Qing all are equipped with AIP propulsion which makes them extremely difficult to detect due to virtually no noise generated. Pakistan Navy has been in love with Agosta 90Bs for this very reason, AIP subs are silent hunters.

Just one question: why can’t PLAN fake some noise signature to fool enemies or potential enemies?

It shouldn’t be difficult.

And those "noises" detected can well be false one.

 

[sweetgrape]

Just one question: why can’t PLAN fake some noise signature to fool enemies or potential enemies?

It shouldn’t be difficult.

And those "noises" detected can well be false one.

That is i want to said!!! But, the troll don't understand, They will laugh at it, haha!! war is war, showing your "fake" weakness if need!

 

[below_freezing]

I assume when gambit stated that sonar and radar are both similar, he was talking about wave physics. However, I fail to see the similarities beyond that point. Sonar utilizes sound the method of detection while radar utilizes radio wave. The environment they operate are vastly different, with different set of challenges for developers. To say that a radar technician would be able to jump right into sonar seems a bit of a stretch to me. While a person well versed in physics/electronics knowledge would have a much easier time adapting to the new trade than the average layman (i.e. me), to suggest such ease of field interchanability seems unreasonable.

no even if you have electronics knowledge it doesn't help in sonars, EM waves and sound waves have completely different behaviors because sound waves depend strongly on the properties of the medium like pressure, temperature, solute concentration, depth, etc that are nonissues in EM.

 

[Contract Killer]

That is i want to said!!! But, the troll don't understand, They will laugh at it, haha!! war is war, showing your "fake" weakness if need!

Man O Man....... I have heard people are brainwashed. But never thought to this extent.

 

[Contract Killer]

Just one question: why can’t PLAN fake some noise signature to fool enemies or potential enemies?

It shouldn’t be difficult.

And those "noises" detected can well be false one.

Now which China is the real one?????

The one which flexing Muscle every here n there. to all most all Nation in East Asia & India. Demonstrating there Fire power.

or

The one Whose General says "we are no match to USA" (all Chinese members here justifies that its a strategic statement with very futuristic approach) & Whose Noisy Diesel Subs are making noise (All Chinese member are covering it by saying that it is just to give fake signature to USA)

And in both case Patting there own back.

Out of the two............ One Of the Dragon is fake.

 

[Aramsogo]

I assume when gambit stated that sonar and radar are both similar, he was talking about wave physics. However, I fail to see the similarities beyond that point. Sonar utilizes sound the method of detection while radar utilizes radio wave. The environment they operate are vastly different, with different set of challenges for developers. To say that a radar technician would be able to jump right into sonar seems a bit of a stretch to me. While a person well versed in physics/electronics knowledge would have a much easier time adapting to the new trade than the average layman (i.e. me), to suggest such ease of field interchanability seems unreasonable.

I've been trying to figure out how a seemingly intelligent person like Gambit can say sonar is pretty much like radar. Passive sonar is listening and digital signal processing. The more microphones you have and the more processing power, the better your passive sonar. Active sonar is actually like a radio/tv broaddcasting station. If you look at the specs, the transmission power is very similar to a TV station. Both passive and active sonar are way too big to fit on a fighter jet.

And contrary to popular belief and most Hollywood movies, a sonar screen does NOT look like a radar screen. A sonar screen is an acoustic waterfall completely different from a radar screen. Gambit, Tell me again how it's easy for a radar tech to understand passive sonar??

 

[gpit]

I assume when gambit stated that sonar and radar are both similar, he was talking about wave physics. However, I fail to see the similarities beyond that point. Sonar utilizes sound the method of detection while radar utilizes radio wave. The environment they operate are vastly different, with different set of challenges for developers. To say that a radar technician would be able to jump right into sonar seems a bit of a stretch to me. While a person well versed in physics/electronics knowledge would have a much easier time adapting to the new trade than the average layman (i.e. me), to suggest such ease of field interchanability seems unreasonable.

I've been trying to figure out how a seemingly intelligent person like Gambit can say sonar is pretty much like radar. Passive sonar is listening and digital signal processing. The more microphones you have and the more processing power, the better your passive sonar. Active sonar is actually like a radio/tv broaddcasting station. If you look at the specs, the transmission power is very similar to a TV station. Both passive and active sonar are way too big to fit on a fighter jet.

And contrary to popular belief and most Hollywood movies, a sonar screen does NOT look like a radar screen. A sonar screen is an acoustic waterfall completely different from a radar screen. Gambit, Tell me again how it's easy for a radar tech to understand passive sonar??

There is a similarity between sound wave and EM wave, for instance they share the same wave equation; but their boundary conditions are different, natures of propaganda are different… the end results will diverge enormously.

Don't worry too much about the gambit. He might read a book or two, touch a weapon here or there, but his physics knowledge fundamentals are deplorable. He even said EM wave phenomena can be explained by using hose water! And a lot people thanked him for that. Look at the following fluid dynamics that he used to explain EM 'knife edge' diffraction effect Funny, indeed!

...

In the above example, we are looking at an airfoil in the motion familiar with flight, either in the horizontal or vertical axis. As the aspect angle changes, deflections are created and at the airfoil's trailing edge, we have the 'knife edge' diffraction effect. Diffraction fields are scattering points. With multiple flight control surfaces creating many diffraction fields, the scattering points can merge as destructive interference or constructive interference. The latter will contribute to the aircraft's total RCS. There will be some reflections on the leading edge that will return to source direction, they are called 'specular reflections'.

Scattering points from diffraction fields are serious enough to warrant a major design factor for the B-2...

...

That’s how I view the problem with democracy: people tend to believe beautiful language and fancy picture and diagrams, and forget the essence. We educated, or relatively educated, must bear this common human weakness in our mind, and be independent and critical.

 

[gambit]

This is going to be good...

I worked at 9500 Godwin Drive in Manassas, VA.

And I cleaned up the old Toshiba gears and help the Micron conversion on the once Toshiba plant on Godwin Drive several years ago.

As for saying passive sonar and airplane radar work on the same principles and the EE are interchangeable, I have never scene that in practice. Nor has that ever been explained to me that way. Sonar requires way more computer processing power, more than would be possible to fit on a fighter jet. Nor have I ever had someone from Lockheed transfer in from the division that makes fighter jets. Most of the techs were ex sonarman. This interchangeability is almost laughable. Air does not equal water. Simple logic should tell you that. If all you have is a hammer, everything looks like a nial. If you are an radar technician, then everything must look like radar??

Then you missed the point completely, which was philosophical, not technical. And if no one ever explained why to you, then you must have never had an excellent teacher/mentor. Too bad for you.

The point was not about how a radar EE would translate his knowledge into sonar, it was about whether he understood how objects are detected via a controlled medium. For radar, that medium is EM, for sonar, it is sound. Both methods of detection requires the user to exercise as much control over the medium as possible in order to extract the maximum amount of data returned by the target. This is a philosophical point, not a technical one. In radar, we have multipaths propagation, same as sonar. This is also a philosophical point, not a technical one. A sub has a problem with 'shadow zones' created by physical structures, man and nature made. So does an aircraft. Underwater we have 'thermoclines' or temperature layers that affect sonar detection over long distances, aka 'deep sound channels'.

SOSUS The "Secret Weapon" of Undersea Surveillance

The deep sound channel is found at the depth where the sound velocity is a minimum. Because sound “rays” always tend to bend away from regions of higher sound velocity, a wave directed upwards from the sound channel axis will be refracted back down again – and a wave directed downwards will be bent upwards. Thus, sound paths from sources in the deep sound channel weave back and forth across the channel axis and – because they become “trapped” in a deep ocean layer away from the surface or bottom – can travel long distances with minimum attenuation.

For radar detection, we have atmospheric plasma layers that either traps or reflects EM signals, making possible long distance 'ham' radio communication, or disruptions of music radios at certain frequencies at different times of day, or degrades over-the-horizon radars, or even atmospheric 'ducting'.

Atmospheric duct - Wikipedia, the free encyclopedia

In telecommunication, an atmospheric duct is a horizontal layer in the lower atmosphere in which the vertical refractive index gradients are such that radio signals (and light rays) (a) are guided or ducted, (b) tend to follow the curvature of the Earth, and (c) experience less attenuation in the ducts than they would if the ducts were not present. The duct acts as an atmospheric dielectric waveguide and limits the spread of the wavefront to only the horizontal dimension.

It also causes long distance propagation of radio signals in bands that would normally be limited to line of sight.

Both sonar and radar uses the 'decibel' method of measurement of power differences.

Synthetic aperature radar (SAR) and its brethen inverse SAR (iSAR) have their sonar cousin in sidescan sonar. The great difference between the two is the frequency employment, radar operates in the ghz range while sonar in low mhz. Keyword search 'towfish sidescan sonar' for interested readers.

Just like radar, sonar exploits the Doppler effect => Products: Doppler Sonar | Marine Equipment For Merchant Marine | Business Fields & Product List | FURUNO's Product Site

Just like radar where short wavelengths or high frequencies are range limited, the bottlenose dophin's sonar pulses are only about 50 microseconds...

Bio-inspired wideband sonar signals based on observations of the bottlenose dolphin (Tursiops truncatus) | Browse - Journal of the Acoustical Society of America

The inspiration comes from the analysis of bottlenose dolphin clicks. These pulses are very short duration, between 50 and 80 μs,...

But that is good enough for hunting.

Whereas the larger whales produces lower freqs and longer pulses that are conducive to long distance navigation/communication...

DOSITS: Blue Whale

Blue whales produce long, multi-part vocalizations that include long pulses, buzzes, and rasps. These vocalizations are typically in the 15-40 Hz range, often below the threshold of human hearing. Even though blue whale calls are generally the same, there are distinct geographic variations that might help scientists distinguish separate populations. Scientists currently use blue whale vocalizations to study their distribution. How blue whales use their vocalizations is not known for certain, but the calls could possibly aid in long-distance communication or navigation.

I could go on and on about the philosophical similarities between the two methods that any good EE would be able to re-train himself once he understood where they differs and where they are alike.

Have you ever even been in a modern sub?? I haven't but I was surrounded by 20 men that have and the Navy did offer us tours but frankly I wasn't that interested (I wanted to do finance). The ride is as smooth as silk. Everything is damped. It's easy to generate noise and make a sub noisier.

Yes, I have. Ever had a 'steel beach' party?

You really don't know what you are talking about on this one.

I highly recommend you watch The Hunt for Red October to learn how sonar works. That movie is considered very accurate by sonarmen and yes the producers of that film did come to Manassas to see how sonar works too (Or so I was proudly told, it was before my time).

Watched it several times. It was good but hardly technically illuminating about sonar.

 

[gambit]

no even if you have electronics knowledge it doesn't help in sonars, EM waves and sound waves have completely different behaviors because sound waves depend strongly on the properties of the medium like pressure, temperature, solute concentration, depth, etc that are nonissues in EM.

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.

 

[gambit]

I've been trying to figure out how a seemingly intelligent person like Gambit can say sonar is pretty much like radar. Passive sonar is listening and digital signal processing. The more microphones you have and the more processing power, the better your passive sonar. Active sonar is actually like a radio/tv broaddcasting station.

That is absolutely amazing. What some people mistakenly called 'passive radar' is actually passive EM sensors and an array of these sensors we have a constellation of 'bi-static' radars. Not much philosophical difference from an array of microphones, no?

And contrary to popular belief and most Hollywood movies, a sonar screen does NOT look like a radar screen. A sonar screen is an acoustic waterfall completely different from a radar screen. Gambit, Tell me again how it's easy for a radar tech to understand passive sonar??

And contrary to your apparently limited understanding, the original radar scope is similar to a sonar scope.

If you think that this...

...Or this...

...Are the original radar scope then it is even more dubious as to your claim about yourself.

The original radar scope was just a little more than the typical oscilloscope...

[1.0] The British Invention Of Radar

The oscilloscope would be connected to the receiver to display the pulse echo on its "cathode ray tube (CRT)", essentially much like a modern TV picture tube. The oscilloscope's sweep would be triggered when the transmitter sent the pulse. The farther away the target was, the longer the delay would be between transmission and reception of the pulse, and this delay could be measured by the distance of the pulse across the oscilloscope screen. The screen could be directly calibrated with the appropriate distance markings. This sort of radar display became known as an "A-scope"

And this is what the 'A-scope' looked like...

Not much different in terms of simplicity from your 'waterfall' sonar display, ain't it?

But do you even know why the modern radar display is much more complex compared to the modern sonar scope?

I will leave that question hanging...

 

[gambit]

Don't worry too much about the gambit. He might read a book or two, touch a weapon here or there,...

Even if true, that would still be at least a magnitude of experience difference between me and ALL of you Chinese conscript rejects COMBINED.

but his physics knowledge fundamentals are deplorable. He even said EM wave phenomena can be explained by using hose water! And a lot people thanked him for that. Look at the following fluid dynamics that he used to explain EM 'knife edge' diffraction effect Funny, indeed!

What is really funny is that once you got busted for claiming that the 10-lambda effect supposedly violated Born Approximation and failed to explain how when I presented Chinese engineers evidence to prove you wrong -- you bailed. And now the only thing you got in any feeble attempt to mock me is your failure to understand how this was used to explain some simple principles to interested laymen.

That’s how I view the problem with democracy: people tend to believe beautiful language and fancy picture and diagrams, and forget the essence. We educated, or relatively educated, must bear this common human weakness in our mind, and be independent and critical.

Compared to the communist sheeple mentality you desired? Equally funny is how you routinely ignored the Chinese boys' fantastic claims about the J-20 and whatever else that practically defied the laws of physics. I guess Chinese solidarity comes before intellectual honesty.

---------- Post added at 12:30 PM ---------- Previous post was at 12:29 PM ----------

I assume when gambit stated that sonar and radar are both similar, he was talking about wave physics. However, I fail to see the similarities beyond that point. Sonar utilizes sound the method of detection while radar utilizes radio wave. The environment they operate are vastly different, with different set of challenges for developers. To say that a radar technician would be able to jump right into sonar seems a bit of a stretch to me. While a person well versed in physics/electronics knowledge would have a much easier time adapting to the new trade than the average layman (i.e. me), to suggest such ease of field interchanability seems unreasonable.

And where did I say so?

 

[Aramsogo]

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).

And really, what does an oscilloscope have anything to do with it. I own a digital oscilloscope, it's not a waterfall.

I'll leave both questions for you hanging....

That is absolutely amazing. What some people mistakenly called 'passive radar' is actually passive EM sensors and an array of these sensors we have a constellation of 'bi-static' radars. Not much philosophical difference from an array of microphones, no?


And contrary to your apparently limited understanding, the original radar scope is similar to a sonar scope.

If you think that this...

...Or this...

...Are the original radar scope then it is even more dubious as to your claim about yourself.

The original radar scope was just a little more than the typical oscilloscope...

[1.0] The British Invention Of Radar

And this is what the 'A-scope' looked like...

Not much different in terms of simplicity from your 'waterfall' sonar display, ain't it?

But do you even know why the modern radar display is much more complex compared to the modern sonar scope?

I will leave that question hanging...