J20 Stealth Fighter

Super Flanker

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In nature there is a simple rule
View attachment 135075

Stealth is mostly propaganda, since matter and energy can not be destroyed, the electromagnetic waves are just scattered to a different direction by the angle of reflection
View attachment 135076

Electromagnetic wave energy is either absorbed or reflected

View attachment 135077

so to explain it simple, J-20 is detectable and it will depend upon the radar transmitting power the range it is detected
View attachment 135079

Each shape has a different scattering pattern a sphere 360 degree, a corner reflector 60 degrees etc etc, however the size of two same shape bodies will have a different amount of energy reflected, for example a larger flat plate will scatter more energy than a smaller flat plate.

View attachment 135080

If you look at the light spectrum each element only absorbs a limited amount of energy, they are the black lines that interrupt the color or colors of the light spectrum, in few words RAM is also propaganda, most energy is reflected, very little absorbed.

So to understand stealth is mostly dependant upon how much energy a radar emits, most radars on aircraft are weak, that is the reason stealth works, but the reality is get a more powerful radar it does not matter is PESA or AESA, a very powerful radar will detect stealth aircraft, a system of radars will do it better.
That law of conservation of energy/mass was given by Antoine Lavoisier in 1789. Anyways Stealth is all about reduced detection or delaying detection as much as possible.

Coming to the radar, then yes, you are right that a more powerful Radar will detect an aircraft (Stealth or non-stealth) at a longer range than a less powerful Radar. This is what I have emphasized on the Forum a lot, India should invest more in Radar Technology, basically "Anti Stealth radars" and also more investment should be done in missile technology. Not saying that we should not develop a Stealth aircraft in counter to J-20 itself but our radars and missile technology should be more better.

L band Radars are best at detecting Stealth aircrafts compared to even S band. Stealth planes are designed in such a way as to counter X band Radars but against S and L band, they fall short.
 

Blademaster

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That law of conservation of energy/mass was given by Antoine Lavoisier in 1789. Anyways Stealth is all about reduced detection or delaying detection as much as possible.

Coming to the radar, then yes, you are right that a more powerful Radar will detect an aircraft (Stealth or non-stealth) at a longer range than a less powerful Radar. This is what I have emphasized on the Forum a lot, India should invest more in Radar Technology, basically "Anti Stealth radars" and also more investment should be done in missile technology. Not saying that we should not develop a Stealth aircraft in counter to J-20 itself but our radars and missile technology should be more better.

L band Radars are best at detecting Stealth aircrafts compared to even S band. Stealth planes are designed in such a way as to counter X band Radars but against S and L band, they fall short.
Yes but aircrafts can only carry a limited bandwidth of power that is largely dictated by the power that their engines deliver. There are a lot of power requirements on a military aircraft that have to power different systems. Power management systems are becoming crucial. Besides power demand requirements & issues, radars not only have to contend with stealth but with other radar bands and other devices using different parts of the EM spectrum that can create interference with its own tracking bandwidth and returns.

Unless we develop a nuclear fusion device that can deliver greater power (ironically that presents its own set of problems because that massive radiation is also lethal to human bodies and can simply kill a human if a human was to pass through its broadcasting coverage), stealth is the dominant form of aerial combat strength. If you cant see them, you can't target them. If they see you first, you become a target.
 

Super Flanker

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Yes but aircrafts can only carry a limited bandwidth of power that is largely dictated by the power that their engines deliver. There are a lot of power requirements on a military aircraft that have to power different systems. Power management systems are becoming crucial. Besides power demand requirements & issues, radars not only have to contend with stealth but with other radar bands and other devices using different parts of the EM spectrum that can create interference with its own tracking bandwidth and returns.

Unless we develop a nuclear fusion device that can deliver greater power (ironically that presents its own set of problems because that massive radiation is also lethal to human bodies and can simply kill a human if a human was to pass through its broadcasting coverage), stealth is the dominant form of aerial combat strength. If you cant see them, you can't target them. If they see you first, you become a target.
"The maximum range of a radar system depends in large part on the average power of its transmitter and the physical size of its antenna. (In technical terms, this is called the power-aperture product.) Doubling the peak power increases the range capabilities by about 25 percent. The longer the pulse length, the greater is the range capability of the radar because of the greater amount of energy transmitted. The pulse repetition rate (PRR) determines the maximum measurable range of the radar".

Not saying that we should develop something like a nuclear fusion device but I am trying to say that we should increase the detection range as much as possible without the radiation becoming so much that it will threaten a given human, in this case pilot.

All things have to make design compromises at the end of the day.
 

HariPrasad-1

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"The maximum range of a radar system depends in large part on the average power of its transmitter and the physical size of its antenna. (In technical terms, this is called the power-aperture product.) Doubling the peak power increases the range capabilities by about 25 percent. The longer the pulse length, the greater is the range capability of the radar because of the greater amount of energy transmitted. The pulse repetition rate (PRR) determines the maximum measurable range of the radar".

Not saying that we should develop something like a nuclear fusion device but I am trying to say that we should increase the detection range as much as possible without the radiation becoming so much that it will threaten a given human, in this case pilot.

All things have to make design compromises at the end of the day.

Of course it is power but the frequency band is also very important in which radar operates. Difference frequencies are used for detecting different size. Generally low frequencies are more effective in penetration. Now, opposite to this ultra low frequencies are used to sent massages to submarines as high frequencies can not penetrate water to reach submarines. The choice of right frequency depends on shape size and material of object to be detected and medium through the waves will travel to reach the object. This is the reason why different frequency radars and seekers used to detect the object. Infrared band is more effective in detecting target with high temperature etc. X band with Higher frequency than L band and S band is more effective in detecting the stealth.
 
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J20!

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Been meaning to post some footage of J20 performances at the Changchung airshow:

Nice demonstration of a capable flight control system leveraging those large all-moving surfaces (vertical stabilizers + canards.


high res photos:





 

jai jaganath

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Been meaning to post some footage of J20 performances at the Changchung airshow:

Nice demonstration of a capable flight control system leveraging those large all-moving surfaces (vertical stabilizers + canards.


high res photos:





So u mean to say plaaf pilots practicing flight controlling and high intensity maneuvers without moving canards and ver stabilizer
 

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Speculations appeared in the Russian and Western press about the aerodynamic similarity of the Chinese J-20 fighter and the experimental Russian 1.44 fighter developed by the MiG Design Bureau in the mid-1990s, which includes an enlarged fuselage, Canards and ventral fins. In this regard, the General Designer of the MiG Design Bureau, V. Barkovsky, agreed to give Kanwa an exclusive interview (the position is indicated by the magazine; on the RSK website it is indicated: Deputy General Director - Director of the Engineering Center "OKB named after A.I. Mikoyan"). According to him, the 1.44 was demonstrated in the mid-1990s, and the PRC expressed great interest in this prototype aircraft and sent a special delegation to Russia to more fully study the development of the 1.44 project. But the MiG design bureau has never held any negotiations with the Chinese on this issue. MiG did not even provide the Chinese side with photographs, and its representatives did not make presentations or speak to the Chinese.


In the same period, the PRC was engaged in the redesign of the JF-17 fighter with the help of the MiG Design Bureau, as a result of which the aerodynamics of the fighter was deeply modernized. JF-17 has lost almost all the features of the MiG-21. Is it possible to assume that the Chinese side took advantage of the opportunity and received some blueprints for 1.44? Answering this question, V. Barkovsky said that it is absolutely impossible. According to him, in Russia there is a strict control over secret technical information. With the exception of separate bilateral programs on which the parties worked together, the Chinese had no opportunity to establish contacts and receive any information about the 1.44 project. This procedure was introduced not only in relation to the Chinese - Russian employees, in principle, cannot bypass the protection system that was created during the Soviet era.


He also added that “this is an imitation - it seems impossible for the Chinese to copy a combat aircraft from the past. Rather, such an imitation is aimed at a promising combat aircraft. In general, in my opinion, the J-20 project includes all the key features of the next generation fighter. Some elements of the F-35 are visible in it, the nose strongly resembles the F-22, there are features of the T-50. In approaches to the design of combat aircraft, the Chinese grew up on the basis of the Soviet system, which is actually a very good start. He believes that this is an acceptable approach in the design of combat aircraft, given the situation in China.

Modern 5th generation fighters usually do not have canards. How does canards affect stealth? Answering this question, the General Designer noted: “The main principle of any aircraft designer is compromise and again compromise. When you take into account one factor, other factors can be weakened to a greater or lesser extent, and it is impossible to achieve perfection in all directions. As for stealth, what is the standard? I believe the tasks of the J-20 determine the type of aerodynamics. In my observation, the J-20 is not exclusively an air superiority fighter. It is rather a multi-functional fighter. How can you compare it with the F-22? In my opinion, an aspect of key importance is the fact that the J-20 was presented to the public a year after the first flight of the T-50, and this underlines the fact that the Chinese are now implementing their own fighter project.

According to V. Barkovsky, “looking at the aerodynamic features of the canards and ventral fins, we must keep in mind that this is a full-scale improvement of the project. In other words, it should improve the ability to fly at supersonic speeds and improve maneuverability. Therefore, the ventral keel favors the stability of the fighter at high speeds. With regard to engine thrust, according to V. Barkovsky, it remains unclear what type of engine is installed on the J-20 or what engine will provide supersonic speed. Nevertheless, the general approach to the aircraft design suggests that the designers paid great attention to the possibility of flying at supersonic speeds and laid significant potential for further development.

Andrey Frolov

 

rockdog

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Speculations appeared in the Russian and Western press about the aerodynamic similarity of the Chinese J-20 fighter and the experimental Russian 1.44 fighter developed by the MiG Design Bureau in the mid-1990s, which includes an enlarged fuselage, Canards and ventral fins. In this regard, the General Designer of the MiG Design Bureau, V. Barkovsky, agreed to give Kanwa an exclusive interview (the position is indicated by the magazine; on the RSK website it is indicated: Deputy General Director - Director of the Engineering Center "OKB named after A.I. Mikoyan"). According to him, the 1.44 was demonstrated in the mid-1990s, and the PRC expressed great interest in this prototype aircraft and sent a special delegation to Russia to more fully study the development of the 1.44 project. But the MiG design bureau has never held any negotiations with the Chinese on this issue. MiG did not even provide the Chinese side with photographs, and its representatives did not make presentations or speak to the Chinese.


In the same period, the PRC was engaged in the redesign of the JF-17 fighter with the help of the MiG Design Bureau, as a result of which the aerodynamics of the fighter was deeply modernized. JF-17 has lost almost all the features of the MiG-21. Is it possible to assume that the Chinese side took advantage of the opportunity and received some blueprints for 1.44? Answering this question, V. Barkovsky said that it is absolutely impossible. According to him, in Russia there is a strict control over secret technical information. With the exception of separate bilateral programs on which the parties worked together, the Chinese had no opportunity to establish contacts and receive any information about the 1.44 project. This procedure was introduced not only in relation to the Chinese - Russian employees, in principle, cannot bypass the protection system that was created during the Soviet era.


He also added that “this is an imitation - it seems impossible for the Chinese to copy a combat aircraft from the past. Rather, such an imitation is aimed at a promising combat aircraft. In general, in my opinion, the J-20 project includes all the key features of the next generation fighter. Some elements of the F-35 are visible in it, the nose strongly resembles the F-22, there are features of the T-50. In approaches to the design of combat aircraft, the Chinese grew up on the basis of the Soviet system, which is actually a very good start. He believes that this is an acceptable approach in the design of combat aircraft, given the situation in China.

Modern 5th generation fighters usually do not have canards. How does canards affect stealth? Answering this question, the General Designer noted: “The main principle of any aircraft designer is compromise and again compromise. When you take into account one factor, other factors can be weakened to a greater or lesser extent, and it is impossible to achieve perfection in all directions. As for stealth, what is the standard? I believe the tasks of the J-20 determine the type of aerodynamics. In my observation, the J-20 is not exclusively an air superiority fighter. It is rather a multi-functional fighter. How can you compare it with the F-22? In my opinion, an aspect of key importance is the fact that the J-20 was presented to the public a year after the first flight of the T-50, and this underlines the fact that the Chinese are now implementing their own fighter project.

According to V. Barkovsky, “looking at the aerodynamic features of the canards and ventral fins, we must keep in mind that this is a full-scale improvement of the project. In other words, it should improve the ability to fly at supersonic speeds and improve maneuverability. Therefore, the ventral keel favors the stability of the fighter at high speeds. With regard to engine thrust, according to V. Barkovsky, it remains unclear what type of engine is installed on the J-20 or what engine will provide supersonic speed. Nevertheless, the general approach to the aircraft design suggests that the designers paid great attention to the possibility of flying at supersonic speeds and laid significant potential for further development.

Andrey Frolov

Why post a 2011 article?
 

rockdog

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very likely fan propaganda but never dismiss a report
Now check the latest report from US and Japan media:

According to an article on the website of military watch of the United States, there are currently eight air brigades in China equipped with j-20 fighters, and the latest one equipped with j-20 fighters is an air brigade belonging to the eastern theater. Since not every brigade is fully staffed with j-20, the total number of j-20 may exceed 150, and it has become the largest fifth generation aircraft group in Asia.

In December 2016, the first batch of j-20 mass-produced models were delivered to the people's air force, and the j-20 was officially put into service. Now, six years have passed. The annual output of j-20 in Chengdu is about 30 +, so there will be 250-300 j-20 fighters by 2025.

In addition, the Chinese air force has about 700 advanced fighters in service in five years, mainly j-20, j-16 and j-10c, which is almost equal to the total number of new fighters of all air forces in western countries in five years.
The Chinese air force has thus become the second largest Tactical Strike Force in the world after the US air force.

At present, j-20 fighters have been equipped in all theaters, and the large-scale equipment of stealth fighters will also have a great impact on the military strategic posture of the entire Asia Pacific region.
According to the 2022 edition of the defense white paper just released by Japan, the number of j-20 stealth fighters in active service of the Chinese air force has increased by 26 in 2021 and may increase by more than 30 in 2022. This means that in the near future, the number of j-20 may catch up with and surpass the U.S. Army's F-22 stealth fighter.
 

rockdog

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Similarly our air to air capability is increasing and leading to less dependency on foreign country
Like astra mk1
Astra mk1 ir
Astra mk2
Astra mk3
Best part leaving mk1 ir everything else is being tested or to to be tested or inducted
You guys have missiles from many nations,the comparisons will be advantage for ur own R&D.

Sadly we only have Russians...
 

jai jaganath

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You guys have missiles from many nations,the comparisons will be advantage for ur own R&D.

Sadly we only have Russians...
Infact our astra mk3 which is ramjet powered AAM is being developed in collaboration with russia
 

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