China claims to have developed most advanced stealth tech even surpassing F22.

[jaydee]

SHANGHAI: A team of Chinese researchers have made a breakthrough in stealth plane technology that could be so significant even local military sources say it should be kept out of the public realm. The team released the technical and design details of an “invisibility circuit” they claim has the potential to help aircraft trick the best early warning systems in use today South China Morning Post said on Monday.

The researchers are affiliated with the Huazhong University of Science and Technology in Wuhan in central China’s Hubei province.

They published their paper in last month’s Journal of Applied Physics, run by the American Institute of Physics.

“It sounds like something that should be kept in the drawer,” said Professor Huang Jun, a military stealth technology researcher at the School of Aeronautic Science and Engineering at Beihang University. Huang was not involved in the research.

“This will be a breakthrough if it works as they claim,” he said.

“That will be really bad news for early warning radars,” he added.

According to their paper, they have created a multi-layer electrical circuit that can “trap” microwaves at ultra-high frequencies, thus confusing radar systems and enabling aircraft to sneak past them.

All radars work by detecting “echoes” of radiowaves, which are bounced off a target. If the waves are absorbed by the new circuit, the target - in this case an aeroplane - would disappear from radar screens.

What is unique about the latest finding is that the material used to create the circuit would be almost impossibly thin. At under one centimetre, it is just a tenth the size of similar products developed by overseas competitors. This means it could be used to coat planes for the first time, pundits say.

Stealth planes including the F-22 and F-35 used by the US military are not quite as evasive as they sound, according to Huang, who said they can be spotted by advanced radar systems even from a considerable distanceChinese scientists develop ‘invisibility circuit’ for stealth planes

 

[Muhammad Omar]

Interesting

 

[jammersat]

of course it will breakthrough in waves

 

[gambit]

According to their paper, they have created a multi-layer electrical circuit that can “trap” microwaves at ultra-high frequencies, thus confusing radar systems and enabling aircraft to sneak past them.

Actually...I mentioned that the US have been working on this method, aka 'active cancellation' at the materials level, on this forum yrs ago.

 

[jammersat]

But still the best wishes to chinese partners , if they indeed made a breakthrough in stealth technology , it was because of the RQ drone they hacked in iran

 

[Akasa]

Can somebody explain the technical workings behind trapping UHF microwaves in circuitry? Does that effectively "ground" the EM?

 

[jammersat]

it's like a tank's reactive armor , only the chinese have put in on their planes , they indeed made a breakthrough

 

[Green Angel]

 

[Penguin]

Of course, for the F-22:

First flight 7 September 1997
Introduction 15 December 2005
Status In service

By the time this new is applied and reaches active combat squadrons, what will be in the US inventory and pipeline?

 

[Providence]

US revealed F117 when it wanted to, cause it was secret ! If china wanted it secret then it could have easily rather than frothing their big mouth !!

 

[gambit]

Can somebody explain the technical workings behind trapping UHF microwaves in circuitry? Does that effectively "ground" the EM?

The general idea is public knowledge for decades.

- The material MUST be a composite, not homogeneous like all steel or all titanium.

- The composite's surface must be a pass through layer.

- The composite's constituents must be electrically conducting.

But is not steel (item 1) electrically conducting to start ? Yes, but a radar cross section (RCS) relies on reflection and diffraction, steel or any other homogeneous material reflects, that rules out item 2. So in order for active cancellation at the materials level to work, the material's surface must be a pass through, or EM transparent, as much as possible. There will always be some reflections, there is no avoiding it, if this material must be strong enough to withstand the stresses of flight. But the material's surface must allow as much of the impinging radar signal to penetrate it as possible. That mean the material must be a composite.

It is item 3 where the execution is difficult.

Design of Broad Band Radar Absorbing Composite Laminates

The purpose of this study is to present the optimal design technology on the broad band radar absorbing composite laminates. The design concept is based on the 2-layer Dallenbach type radar absorber, in which the composite laminates act as the lossy layers. The radar absorbing function was achieved by controlling the electromagnetic property of the composite laminates by means of adding carbon nano materials into the matrix resin of the fiber-reinforced composite laminates.

The Dallenbach layering method is one of many attempts to create a broadband composite. To make the layers electrically active, as in creating a giant continuous transistor-capacitor circuit out of the composite's layers, is far beyond the Dallenbach layering method.

An Error Occurred Setting Your User Cookie
8.5: CIRCUIT ANALOG RAM AND FREQUENCY-SELECTIVE SURFACES | IHS Engineering360

The circuit analog method is the next technical hurdle, especially for flight. In the source above, the crosses are literal, meaning the layer must contain electrically conducting patterns of crosses. All the crosses must be uniform in spacing to each other. As the design gets more complex, crosses may not be used, or maybe used in cooperation with other shapes. Do note that the first source have Chinese names in it.

All of this cannot be something like steel or even aluminum. It must be lighter, as thin as possible as in millimeters, and must strong enough to withstand the stresses of flight. Twelve millimeters is half inch and is awfully thick for flight. A radome must be a pass through and the F-16's radome is not 12 mm, or .5 inch, in thickness. More like around 6-7 millimeters and it can withstand Mach. So now there is the problem of physical thickness vs electrical thickness. Minimize physical thickness for weight consideration for flight, but must increase electrical thickness to conduct any signal from X to UHF.

 

[Sanchez]

Nobody in China claims to have developed most advanced stealth tech even surpassing F22！！！！

Source: China claims to have developed most advanced stealth tech even surpassing F22.

 

[nik141993]

Well that's great ,China only lack in ectronics & engine technology but they will close the gap in next decade ,all the best of luck to them

 

[Spy Master]

The general idea is public knowledge for decades.

- The material MUST be a composite, not homogeneous like all steel or all titanium.

- The composite's surface must be a pass through layer.

- The composite's constituents must be electrically conducting.

But is not steel (item 1) electrically conducting to start ? Yes, but a radar cross section (RCS) relies on reflection and diffraction, steel or any other homogeneous material reflects, that rules out item 2. So in order for active cancellation at the materials level to work, the material's surface must be a pass through, or EM transparent, as much as possible. There will always be some reflections, there is no avoiding it, if this material must be strong enough to withstand the stresses of flight. But the material's surface must allow as much of the impinging radar signal to penetrate it as possible. That mean the material must be a composite.

It is item 3 where the execution is difficult.

Design of Broad Band Radar Absorbing Composite Laminates

The Dallenbach layering method is one of many attempts to create a broadband composite. To make the layers electrically active, as in creating a giant continuous transistor-capacitor circuit out of the composite's layers, is far beyond the Dallenbach layering method.

An Error Occurred Setting Your User Cookie
8.5: CIRCUIT ANALOG RAM AND FREQUENCY-SELECTIVE SURFACES | IHS Engineering360

The circuit analog method is the next technical hurdle, especially for flight. In the source above, the crosses are literal, meaning the layer must contain electrically conducting patterns of crosses. All the crosses must be uniform in spacing to each other. As the design gets more complex, crosses may not be used, or maybe used in cooperation with other shapes. Do note that the first source have Chinese names in it.

All of this cannot be something like steel or even aluminum. It must be lighter, as thin as possible as in millimeters, and must strong enough to withstand the stresses of flight. Twelve millimeters is half inch and is awfully thick for flight. A radome must be a pass through and the F-16's radome is not 12 mm, or .5 inch, in thickness. More like around 6-7 millimeters and it can withstand Mach. So now there is the problem of physical thickness vs electrical thickness. Minimize physical thickness for weight consideration for flight, but must increase electrical thickness to conduct any signal from X to UHF.

Man you have a lot of knowledge in this field...You should be a teacher, seriously...!

 

[jaydee]

But still the best wishes to chinese partners , if they indeed made a breakthrough in stealth technology , it was because of the RQ drone they hacked in iran

And the origin of USAF's first stealth plane had it from a German stealth plane.