J20 Stealth Fighter

[Gyyan]

WS-15 is a heavy engine -- 180kN

WS-19 is China's 110kN medium engine

You don't get the context anyway dumb bitches like you have their own benefits in narrative planting.

 

[SexyChineseLady]

2022 Keynote Report at China Aviation Industry Conference on Chinese aircraft engine development. It also states that the 4th Gen engine for J-20 has already done its maiden flight but not inducted yet.

 

[SexyChineseLady]

Chinese materials science has reached a point that critical engine parts can last 50,000 hours compared to global standard of 20,000 hours!

 

[strcat]

抱歉，我们这里没有人能读懂或听懂中文。
即使您写的是我们的屁股，我们也无法真正理解，因此英语或印地语视频会比任何中文 bs 更有帮助。
[/引用]

 

[SexyChineseLady]

Go here for more on the AVIC keynote address -- much more than just the WS-15 and J-20! It marks the state of China's engine industry and it is will be extremely intriguing and fun to look forward to!

Exciting Times for Chinese Aircraft Engines!

WS-13 -- China's current medium-sized engine for JF-17 and J-35. Development began in late 1990s and limited serial production began in 2009. Testing on FC-1, JF-17, FC-31 and J-35 prototypes began from 2010 onward. Mass production line for 100 kN WS-13E established in 2021.

defenceforumindia.com

 

[rockdog]

The Turkey Kizilelma UAV looks quite like J20

 

[MiG-29SMT]

You are welcome, btw there are also version for F-35 and Su-57

F-35A Radar scattering simulation

Introduction F-35 is the backbone of American stealth fighter fleet, it is intended to replace F-16, F-18C/D, Harrier and A-10. There are currently 3 versions of F-35 which are F-35A, F-35B and F-3…

basicsaboutaerodynamicsandavionics.wordpress.com

Su-57 Radar scattering simulation

Introduction Su-57 is the first aircraft in Russian military service designed with stealth technology, it is intended to replace Su-27/30/35 family and server as the Russian answer to the American …

basicsaboutaerodynamicsandavionics.wordpress.com

this articles are mostly generalizations, no aircraft is invisible to radar,


most is propaganda, and most articles are not really based upon sound physics, Stealth helps but is not really as people think


TheSu-35 for example has and Infrared detection capability and some radars on frequencies that makes hard for even F-22 difficult to hide, the Su-35 downed in Ukraine has its IRST system sent to the west to find its capabilities since its capable of detecting a F-35 at 90 km

 

[MiG-29SMT]

limitations of RAM

According to simulation and experiment results, the present three-dimensional metamaterial absorber can realize an absorptivity of more than 90% in a wide band of 3.53–24.00 GHz, and improve absorbing efficiency for transverse magnetic (TM) waves of oblique incidence angle from 0° to 70°.


https://www.nature.com/articles/s41598-018-23286-6

https://www.researchgate.net/figure/RADAR-frequencies-and-electromagnetic-spectrum_fig2_317427496

Basically RAM can not protect for all frequencies

 

[J20!]

this articles are mostly generalizations, no aircraft is invisible to radar,


most is propaganda, and most articles are not really based upon sound physics, Stealth helps but is not really as people think


TheSu-35 for example has and Infrared detection capability and some radars on frequencies that makes hard for even F-22 difficult to hide, the Su-35 downed in Ukraine has its IRST system sent to the west to find its capabilities since its capable of detecting a F-35 at 90 km

No where do the papers suggest stealth jets are "invisible to radar".

Russian Airforce experience over Ukraine shows just how vulnerable non stealth aircraft are over defended airspace.

If Su35s can't survive old Ukrainian BUK medium range SAMs and S300s how would they fare against F35s or any stealth aircraft for that matter.

You've made this argument before, but signature reduction is the future of aircombat.

 

[Super Flanker]

this articles are mostly generalizations, no aircraft is invisible to radar,


most is propaganda, and most articles are not really based upon sound physics, Stealth helps but is not really as people think


TheSu-35 for example has and Infrared detection capability and some radars on frequencies that makes hard for even F-22 difficult to hide, the Su-35 downed in Ukraine has its IRST system sent to the west to find its capabilities since its capable of detecting a F-35 at 90 km

I think you misunderstand what is the whole definition of stealth when we refer to Stealth aircrafts, stealth does not mean absolute invisibility and no one is saying that if any aircraft is "Stealth" then it is completely invisible to any radar. Stealth is only reduced detection, the whole point of stealth is that you will have a RCS low enough that you are able to get close enough to your target, shoot your weopons (i.e missiles, bombs etc) before you are detected and the enemy does the same to you, basically you want a "look first & shoot first" capability. Any radar in this world can detect and track any stealth aircraft, for example even a MiG-21's radar would be able to detect & track an F-22 but the distance at which that would happen would be tactically irrelevant since the F-22 would have detected the MiG-21 and already fired its missiles at the MiG-21 long before the MiG-21 would have any clue as to what is happening.

 

[StealthFlanker]

this articles are mostly generalizations, no aircraft is invisible to radar,
most is propaganda, and most articles are not really based upon sound physics, Stealth helps but is not really as people think

No where does it suggest that any aircraft is invisible to radar, and stealth has never been about being absolutely invisible. Stealth is simply about reducing enemy detection range so that you can engage them before they can do the same.
And no, the article is not a "generation", I would dare say that it is as accurate and non bias as you can get without access to the actual physical airframe.

TheSu-35 for example has and Infrared detection capability and some radars on frequencies that makes hard for even F-22 difficult to hide

Irbis-E operate in X-band (8-12 GHz) so pretty much the optimum frequency for stealth aircraft.
If you are referring to the Tikhomirov NIIP L-band on the leading edge of Su-35, then keep in mind that it is not a radar but rather an IFF system, it only has 1 row of T/R modules, which mean it can't even steer vertically to determine target height. Furthermore, given that beam width is directly proportional to wavelength and inversely proportional to antenna area, a L-band antenna of that size will generate a radio beam so wide that it is effectively useless for target direction finding.

the Su-35 downed in Ukraine has its IRST system sent to the west to find its capabilities since its capable of detecting a F-35 at 90 km

To be honest, it really doesn't help your case when you have to make up story as an attempt to support your point. The detection range of OLS-35 is 90 km only against big target such as Su-30, and only from the rear aspect. If the two aircraft are flying toward each other, then the detection range reduced to only 35 km. To make matter worse, to be able to launch missile, you need to measure distance to target and their velocity. On OLS-35, it would be done by the laser range finder system, and the range of this system is only 20 km

 

[KurtisBrian]

Bet, Stealth would also help a fighter break lock once a missile or jet has it.

 

[KurtisBrian]

looked it up.



at the end this guy says that breaking missile lock is an advantage.










ToughSF

@ToughSf
·
Jun 11, 2018

"The basis of missile combat is maneuvering so that the enemy is in the NEZ (or at least in a high-confidence area) while you yourself have a good chance of escape.




















ToughSF

@ToughSf
·
Jun 11, 2018

Getting behind the enemy being the traditional example for this, your IR sensor has the brightest part exposed to itself, and any course change the enemy makes brings the interception point closer (which means the missile has more remaining energy to use)."




















ToughSF

@ToughSf
·
Jun 11, 2018

"For radar guided missiles, especially old pulse-doppler radars, you can also do very rapid deceleration to break lock, but that's a lot harder to do with AESA. IR Chaff is supposed to do the same."

















ToughSF

@ToughSf


"Stealth is a very simple advantage: you can get into an advantageous position without the enemy knowing about you, and only noticing your launch later (which means he has less time to maneuver). It also makes it easier to break missile lock."

 

[MiG-29SMT]

I think you misunderstand what is the whole definition of stealth when we refer to Stealth aircrafts, stealth does not mean absolute invisibility and no one is saying that if any aircraft is "Stealth" then it is completely invisible to any radar. Stealth is only reduced detection, the whole point of stealth is that you will have a RCS low enough that you are able to get close enough to your target, shoot your weopons (i.e missiles, bombs etc) before you are detected and the enemy does the same to you, basically you want a "look first & shoot first" capability. Any radar in this world can detect and track any stealth aircraft, for example even a MiG-21's radar would be able to detect & track an F-22 but the distance at which that would happen would be tactically irrelevant since the F-22 would have detected the MiG-21 and already fired its missiles at the MiG-21 long before the MiG-21 would have any clue as to what is happening.

View attachment 186294

MiG-21 is an aircraft, but the radar does the detection

Pt is the power of the radar thus detection is directly related since it is a multiplication to the power of the transmitting radar, more power higher detectability, the formula shows Irbis will detect at longer range than the small radar of MiG-21the same target F-22.

The radar range equation represents the physical dependences of the transmit power, which is the wave propagation up to the receiving of the echo signals. The power Pe returning to the receiving antenna is given by the radar equation, depending on the transmitted power PS, the slant range R, and the reflecting characteristics of the aim (described as the radar cross section σ). At the known sensibility of the radar receiver, the radar equation determines the achieved by a given radar theoretically maximum range. Furthermore one can assess the performance of the radar set with the radar range equation (or shorter: the radar equation).


https://www.radartutorial.eu/01.basics/The Radar Range Equation.en.html

RCS only represents the scattering or reflection of the electromagnetic waves angular direction or spikes.

Consider the transmitting wave length, since each wave length has different range, thus on stealth fighters, larger radar waves have longer detection range

 

[Super Flanker]

MiG-21 is an aircraft, but the radar does the detection

View attachment 186362

Pt is the power of the radar thus detection is directly related since it is a multiplication to the power of the transmitting radar, more power higher detectability, the formula shows Irbis will detect at longer range than the small radar of MiG-21the same target F-22.

The radar range equation represents the physical dependences of the transmit power, which is the wave propagation up to the receiving of the echo signals. The power Pe returning to the receiving antenna is given by the radar equation, depending on the transmitted power PS, the slant range R, and the reflecting characteristics of the aim (described as the radar cross section σ). At the known sensibility of the radar receiver, the radar equation determines the achieved by a given radar theoretically maximum range. Furthermore one can assess the performance of the radar set with the radar range equation (or shorter: the radar equation).


https://www.radartutorial.eu/01.basics/The Radar Range Equation.en.html

RCS only represents the scattering or reflection of the electromagnetic waves angular direction or spikes.

Consider the transmitting wave length, since each wave length has different range, thus on stealth fighters, larger radar waves have longer detection range

Ofcource it's the aircraft's radar that does the detection, no one is suggesting otherwise. More the powerful a radar, the better it will be at tracking objects from a far away distance/which have very low RCS as in stealth planes (i.e Su-57, F-22, F-35, J-20, F-117 etc). For example lets take the example of a MiG-21 & MiG-31. The MiG-21 can use for e.g RP-21 Sapfir radar system, the MiG-31 on the other hand can use Phazotron PESA radar, the Phazotron on the MiG-31 is much more powerful than the RP-21 radar on the MiG-21 and therefore it will be able to detect any target further away and before the RP-21 would be able to do the same.

 

[MiG-29SMT]

No where does it suggest that any aircraft is invisible to radar, and stealth has never been about being absolutely invisible. Stealth is simply about reducing enemy detection range so that you can engage them before they can do the same.
And no, the article is not a "generation", I would dare say that it is as accurate and non bias as you can get without access to the actual physical airframe.


Irbis-E operate in X-band (8-12 GHz) so pretty much the optimum frequency for stealth aircraft.
If you are referring to the Tikhomirov NIIP L-band on the leading edge of Su-35, then keep in mind that it is not a radar but rather an IFF system, it only has 1 row of T/R modules, which mean it can't even steer vertically to determine target height. Furthermore, given that beam width is directly proportional to wavelength and inversely proportional to antenna area, a L-band antenna of that size will generate a radio beam so wide that it is effectively useless for target direction finding.


To be honest, it really doesn't help your case when you have to make up story as an attempt to support your point. The detection range of OLS-35 is 90 km only against big target such as Su-30, and only from the rear aspect. If the two aircraft are flying toward each other, then the detection range reduced to only 35 km. To make matter worse, to be able to launch missile, you need to measure distance to target and their velocity. On OLS-35, it would be done by the laser range finder system, and the range of this system is only 20 km

you seem to think a hot nozzle can be hidden easily, that is not the fact, for starters J-20 has round nozzles where the hot part, afterburner is easily seen and open to external detection and so is F-35

A round nozzle is used since to spin the engine blades they need to do revolutions of 360 degrees, the nozzle does not need to be round but other shape rather than round will mean thrust loses.

Flat nozzle design advantages

Since about the 80s of the last century, aircraft designers have discovered a number of advantages for military aircraft engines, which can bring the use of a nozzle with a flat cross-sectional shape.

On the one hand, such a design feature improves the take-off and landing performance (CV) of the aircraft and makes it more maneuverable.

And on the other, it allows the combat vehicle to become less noticeable to the enemy radar. This is because the contours of an axisymmetric nozzle of circular cross-section are very difficult to coordinate with other structural elements of the aircraft to make the aircraft not so noticeable to radars. This is much easier to achieve if you use a flat "jet" nozzle. In addition, in order to further reduce the radio sensitivity, in the manufacture of such a nozzle, materials capable of absorbing radiation are used.

Additionally, the infrared radiation of an aircraft using this nozzle shape is also reduced. This allows you to achieve a ratio of the height and width of the nozzle, significantly reducing the temperature of the outgoing jet.

Of course, this form of nozzle also has drawbacks. Firstly, when switching from a circular cross section of the engine to a rectangular nozzle, some pressure loss occurs. At best, about five percent is lost. The second disadvantage is the need to increase the stiffness and strength of the nozzle, since a design of this shape experiences a greater load than a round nozzle.

https://en.topwar.ru/171233-nuzhno-li-rossijskim-voennym-samoletam-ploskoe-soplo.html

Ideally this is the best stealth nozzle but it has high thrust loses

so to put it mildly some variants of J-20 use the same engine Su-30 uses and WS-10 is no stealth engine

Results of this study indicate that the thrustvectoring capability of some of the present postexit-vane configurations was competitive with other thrust-vectoring concepts reported in the literature. However, all the present post-exit-vane configurations incurred large resultant gross-thrust losses to achieve vectored thrust. In general, any change in geometry which produced larger thrust-vector angles also caused larger resultant thrust losses.

https://core.ac.uk/download/pdf/42832962.pdf

 

[MiG-29SMT]

No where does it suggest that any aircraft is invisible to radar, and stealth has never been about being absolutely invisible. Stealth is simply about reducing enemy detection range so that you can engage them before they can do the same.
And no, the article is not a "generation", I would dare say that it is as accurate and non bias as you can get without access to the actual physical airframe.


Irbis-E operate in X-band (8-12 GHz) so pretty much the optimum frequency for stealth aircraft.
If you are referring to the Tikhomirov NIIP L-band on the leading edge of Su-35, then keep in mind that it is not a radar but rather an IFF system, it only has 1 row of T/R modules, which mean it can't even steer vertically to determine target height. Furthermore, given that beam width is directly proportional to wavelength and inversely proportional to antenna area, a L-band antenna of that size will generate a radio beam so wide that it is effectively useless for target direction finding.


To be honest, it really doesn't help your case when you have to make up story as an attempt to support your point. The detection range of OLS-35 is 90 km only against big target such as Su-30, and only from the rear aspect. If the two aircraft are flying toward each other, then the detection range reduced to only 35 km. To make matter worse, to be able to launch missile, you need to measure distance to target and their velocity. On OLS-35, it would be done by the laser range finder system, and the range of this system is only 20 km

speed is another fact faster means hotter

aircraft as they travel generate heat, stealth aircraft do it too, on space shuttles the heat barrier was made to do not melt the fuselage of the space shuttles but air remain hot

See that is just the airframe

see the exhaust nozzle is far much hotter

 

[MiG-29SMT]

No where does it suggest that any aircraft is invisible to radar, and stealth has never been about being absolutely invisible. Stealth is simply about reducing enemy detection range so that you can engage them before they can do the same.
And no, the article is not a "generation", I would dare say that it is as accurate and non bias as you can get without access to the actual physical airframe.


Irbis-E operate in X-band (8-12 GHz) so pretty much the optimum frequency for stealth aircraft.
If you are referring to the Tikhomirov NIIP L-band on the leading edge of Su-35, then keep in mind that it is not a radar but rather an IFF system, it only has 1 row of T/R modules, which mean it can't even steer vertically to determine target height. Furthermore, given that beam width is directly proportional to wavelength and inversely proportional to antenna area, a L-band antenna of that size will generate a radio beam so wide that it is effectively useless for target direction finding.


To be honest, it really doesn't help your case when you have to make up story as an attempt to support your point. The detection range of OLS-35 is 90 km only against big target such as Su-30, and only from the rear aspect. If the two aircraft are flying toward each other, then the detection range reduced to only 35 km. To make matter worse, to be able to launch missile, you need to measure distance to target and their velocity. On OLS-35, it would be done by the laser range finder system, and the range of this system is only 20 km

obviously Su-30 is not the hottest thing to see

see Su-27 and F-35 image both are visible

 

[StealthFlanker]

you seem to think a hot nozzle can be hidden easily, that is not the fact, for starters J-20 has round nozzles where the hot part, afterburner is easily seen and open to external detection and so is F-35

you don't necessary need square nozzle to mask the hot flame, the vertical stabilator can do that task as well. And besides, if two aircraft flying toward each other then the nozzle will be masked

 

[StealthFlanker]

speed is another fact faster means hotter
View attachment 186369
aircraft as they travel generate heat, stealth aircraft do it too, on space shuttles the heat barrier was made to do not melt the fuselage of the space shuttles but air remain hot
See that is just the airframe

View attachment 186370
see the exhaust nozzle is far much hotter

You are basically arguing something that everybody already know. Yes, the exhaust nozzle is hotter than the aircraft skin. That why OLS-35 can detect Su-30 at distance of 90 km from the rear but only 35 km from the frontal aspect
Oh and btw, except for maybe the Mig-31, most aircraft doesn't cruise at Mach 2