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Chengdu J-20 5th Generation Aircraft News & Discussions

I'd be skeptical of this 0.5sq/m2 claim until the official's credentials were verified. There's no way the Russians will not evolve the T-50 to a true LO stealth aircraft unless they really are going to do nothing about the blades.
whether the 0.5m2 is true or not, but the fact is the mighty Soviet aviation industry was long gone, no exciting things coming from Russia for decades, and now the T-50 is a big disappointment of their true capability
 
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Russian Embassy in India official website states 0.5m2 RCS for T-50/Pak-Fa

India, Russia close to pact on next generation fighter

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Ouch! It's not even 5th generation. I wonder if it can supercruise?

Maybe we can sell J-20 export version to Russia in the future.
 
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whether the 0.5m2 is true or not, but the fact is the mighty Soviet aviation industry was long gone, no exciting things coming from Russia for decades, and now the T-50 is a big disappointment of their true capability

I don't think so
 
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Reconciling my estimate of 3m2 RCS with Russian embassy statement of 0.5m2 RCS

The statement of T-50/Pak-Fa 0.5m2 RCS on the official Russian embassy website has existed for two years. Sukhoi had ample opportunity to dispute the 0.5m2 RCS. The Russian embassy in India statement of 0.5m2 RCS makes sense, because all of us can clearly see the glaring deficiencies in the third T-50/Pak-Fa prototype (see first citation below).

However, I still have to explain the discrepancy between my estimate from January 2011 (see second citation below) and the lower RCS by the Russian embassy in India. My estimate of a frontal RCS of 3m2 for the T-50/Pak-Fa was probably correct, but it was incomplete.

I want to clarify that my comparison between the Russian T-50/Pak-Fa and the French Rafale was strictly an exercise in determining the RCS of the Russian fighter. Obviously, in a real war, a "clean" Rafale is impossible. It has to carry missiles and bombs, which destroys the Rafale's RCS rating.

Anyway, let me continue with my analysis from last year.

From the front, the T-50/Pak-Fa and Rafale are both deficient with a metal-framed cockpit canopy. The Rafale is further deficient with a round nose (not having a shaped nose) and lacks RAM coating. The T-50/Pak-Fa has its own problems of a protruding IRST probe and straight engine inlets (whereas the Rafale engine is 90% hidden).

Also, both the T-50/Pak-Fa and Rafale lack gold-colored transparent cockpit canopy RAM. I have never seen a picture of the T-50/Pak-Fa with gold-colored RAM and I can only conclude the Russians have been unable to develop transparent RAM.

The 0.5m2 RCS for the T-50/Pak-Fa is an average from all perspectives. Last year, I had forgotten to highlight the T-50's superiority to the French Rafale in side-aspect RCS. From the side, the T-50/Pak-Fa has a partially canted airduct, which deflects radar away from the emitter.

Additionally, the T-50's RAM coating provides a much lower RCS in comparison to the French Rafale. The T-50's canted vertical stabilizers further reduce its side-profile RCS. In a real war, the T-50 was always far superior to the French Rafale. The T-50 has internal weapon bays and its RCS was always much lower than a French Rafale in combat.

After considering the T-50's superiority over the French Rafale in side-aspect RCS, I concur with the overall 0.5m2 RCS for the Russian T-50/Pak-Fa.

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Citations:

My annual review of T-50/Pak-Fa progress or lack thereof

Two years have passed since the January 2010 unveiling of the T-50/Pak-Fa. Let's look at the stealth design issues that remain.

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By the way, none of the Russian T-50/Pak-Fa problems exists on the Chinese J-20 Mighty Dragon stealth fighter.

Terrific J-20 Mighty Dragon close-up photographs

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J-20 taxiing

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Another day of tests

[Note: Thank you to Hu Songshan and J-20 Mighty Dragon Continue Flight Testing in February 2012 ~ Chinese Military Review]
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We know T-50 is inferior in stealth to French Rafale, which means T-50's RCS > 1m2

According to GlobalSecurity, the French Rafale has a RCS of 1 m2. Since the Rafale has most of its engine blades shielded by an almost-serpentine air-inlet, the T-50's fully-exposed engine blades will cause the T-50's RCS to be greater than the Rafale's 1m2.

However, the T-50 has a shaped-nose. This means the T-50's RCS is probably a little lower than a F-16. My best estimate of the T-50's RCS is 3m2. (See GlobalSecurity RCS chart below. The T-50's RCS is most likely bound by the F-16 as an upper limit and the French Rafale as the lower limit.) Exposed engine blades are a glaring deficiency for stealth. However, I awarded points to the T-50 for having a shaped-nose, canted air-ducts and tails, and planform alignment.

My estimate of J-20's RCS is 0.005-0.0001 m2 (or -30 to -40 db)

From the front, the J-20 matches the F-22's stealth profile. While the J-20 is flying at you, the incremental increase in area from its canards is minimal (e.g. look at a piece of paper edge-wise; you only see a line). Also, the J-20's canards are probably made of composite material, coated with RAM, and curve-shaped to deflect radar waves. For all intents and purposes, the J-20 has a F-22 RCS frontal profile of 0.0001 m2.

From the rear, with its circular saw-toothed engine nozzles, the J-20 looks like the F-35 and it should have a similar rear RCS of 0.005 m2.

In conclusion, depending on your point of view, the J-20's RCS ranges from 0.005 to 0.0001 m2 (or -30 to -40 db).

Radar Cross Section (RCS)

Radar Cross Section (RCS) / RCS (m2) / RCS (dB)

  1. automobile 100 20
  2. B-52 100
  3. B-1(A/B) 10
  4. F-15 25
  5. Su-27 15
  6. cabin cruiser 10 10
  7. Su-MKI 4
  8. Mig-21 3
  9. F-16 5
  10. F-16C 1.2
  11. man 1 0
  12. F-18 1
  13. Rafale 1
  14. B-2 0.75 ?
  15. Typhoon 0.5
  16. Tomahawk SLCM 0.5
  17. B-2 0.1 ?
  18. A-12/SR-71 0.01 (22 in2)
  19. bird 0.01 -20
  20. F-35 / JSF 0.005 -30
  21. F-117 0.003
  22. insect 0.001 -30
  23. F-22 0.0001 -40
  24. B-2 0.0001 -40
 
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I wonder where Martian 2 pulls out all those fantastic numbers!! Gotta bet its from Planet (Martian 2's) Uranus. But then gotta give the dude his credit. No matter how stupid, how inane and how ridiculous his posts and "calculations" - all based on assumptions, the dude passionately believes in what he posts. He passionately believes that the stupidity displayed in his posts is the standard for intelligence.

Keep regaling us with your antics, jester.
 
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Here's Bill Sweetman's preliminary analysis of the PAK FA posted back in 2010. :lol:

The big new feature of the T-50 is stealth. The aircraft that flew today is a prototype - and it does not show visible features like a frameless canopy and panel alignment that you'd expect on a production aircraft. Other not-very-stealthy-looking features include the gaps around the inlet (compare the YF-23) and a spherical infrared search and track housing in front of the windshield. And, of course, the nozzles are round. But it has a chined forebody, edge alignment and (probably) inlet line-of-sight blockage and internal weapons.

Apparently the designers and systems analysts have looked at the thorny question of "how much stealth do we want to pay for?" and have come up with a different answer than the F-22 designers. The fact that the armed forces of potential adversaries don't have S-300 and S-400 missiles may have something to do with that answer.

T-50: A Preliminary Analysis
 
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I wonder where Martian 2 pulls out all those fantastic numbers!! Gotta bet its from Planet (Martian 2's) Uranus. But then gotta give the dude his credit. No matter how stupid, how inane and how ridiculous his posts and "calculations" - all based on assumptions, the dude passionately believes in what he posts. He passionately believes that the stupidity displayed in his posts is the standard for intelligence.

Keep regaling us with your antics, jester.
Notice his 'citations' -- Himself. :lol:
 
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World stealth fighter rankings

vmoc4.jpg


#1 F-22 Raptor - RCS is 0.0001 m2 (from GlobalSecurity citation)

#2 J-20 Mighty Dragon - RCS is intermediate between F-22 and F-35 (Frontal and side-aspect RCS is 0.0001 m2 like F-22. Rear-aspect RCS with round LOAN engine nozzles is 0.005 m2 like F-35. See my previous analyses.)

#3 F-35 Joint Strike Fighter - RCS is 0.005 m2 (from GlobalSecurity citation)

#4 T-50/Pak-Fa - RCS is 0.5 m2 (from Russian Embassy in India official website citation)

References:

GlobalSecurity: Radar Cross Section (RCS)

Russian Embassy in India official website: India, Russia close to pact on next generation fighter
 
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whether the 0.5m2 is true or not, but the fact is the mighty Soviet aviation industry was long gone, no exciting things coming from Russia for decades, and now the T-50 is a big disappointment of their true capability

How is it a big disappointment? Did you get to fly it? Did you get your hands on some classified information’s? What you think is irrelevant, your eye-ball test is irrelevant, and you preconceived and false notions of aerospace design is irrelevant. The pak-fa far exceeds all other known fighter aircraft in range, speed, ect. I would hardly call that a disappointment. I would not call the avionics in the pak-fa a disappointment either.

As for the RCS claim it came from a journalist--I have seen the original broadcast where they claimed so, most Chinese on this forum call Russians liars and Russian journalists notoriously inaccurate. When Russian journalist report something about China that doesn’t sit well with Chinese cheerleaders than Russians are liars, when journalist report something that makes Russia look bad than it is the definitive truth.

I wonder where Martian 2 pulls out all those fantastic numbers!! Gotta bet its from Planet (Martian 2's) Uranus. But then gotta give the dude his credit. No matter how stupid, how inane and how ridiculous his posts and "calculations" - all based on assumptions, the dude passionately believes in what he posts. He passionately believes that the stupidity displayed in his posts is the standard for intelligence.

Keep regaling us with your antics, jester.

He got his numbers from thin air. In the real world aircraft are tested and scrutinized by mathematical models that predict complex wave scattering as well as anechoic chambers. His layman analysis is not only flawed it is butchered. His reasoning is something like this: The Rafales’ RCS is 1m2 from the front therefore the pak-fa’s RCS should be much larger because its compressor blades are exposed. He fails to take into all other factors such as pylons, the scatter of EM energy from the cockpit and even an aircraft’s flaps, in the Rafales’ case its flaps are perpendicular in relation to the front of the aircraft--the pak-fa has no such problem.

He also called Boeing liars when they claimed there Silent Eagle could achieve the same frontal RCS as the F-35. Comparing the latest Flankers including the Chinese J-11 and SU-35 we know that both aircraft have had significant RCS reductions. There are figures of 1m2 to 3m2 for both aircraft, so how is that possible? How do you take a Flanker airframe and reduce the RCS by that large of a margin especially with fully exposed compressor blades and all? This is where his layman analysis falls apart, by his logic, if an SU-30 has a RCS of 10m2 than the SU-35 and J-11 also have to have the same RCS but this is not the case.

Here is one of Martian’s old posts, in it he is trying to convince everyone that the WZ-10 is stealthy despite a vertical freaking stab, pylons, fixed landing gears, gun, FLIR probe, a metal canopy, and too many protrusions to count. Here it is enjoy everyone:



What about the stealth shape of the fuselage to reflect radar away from the emitter? Or are your eyes incapable of seeing the obvious faceted shaping?

If you’re having problems comprehending the stealth shaping, let me educate you. When radar hit’s the top-half of the WZ-10, it reflects away into space. When radar hit’s the bottom-half of the WZ-10, it reflects into the ground. Either way, the radar is redirected away from the receiver.


So while he nit picks the pak-fa over the slightest of things such as a small IRST probe, he turns around and calls the WZ-10 stealthy even though it has an enormous FLIR and gun hanging off it nose. If it’s Chinese, it’s stealthy no matter what, you see, the WZ-10 is special, it can still be stealthy even with a framed canopy, and FLIR but the pak-fa is definitely not stealthy. :lol:
 
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Reconciling my estimate of 3m2 RCS with Russian embassy statement of 0.5m2 RCS

The statement of T-50/Pak-Fa 0.5m2 RCS on the official Russian embassy website has existed for two years. Sukhoi had ample opportunity to dispute the 0.5m2 RCS. The Russian embassy in India statement of 0.5m2 RCS makes sense, because all of us can clearly see the glaring deficiencies in the third T-50/Pak-Fa prototype (see first citation below).

However, I still have to explain the discrepancy between my estimate from January 2011 (see second citation below) and the lower RCS by the Russian embassy in India. My estimate of a frontal RCS of 3m2 for the T-50/Pak-Fa was probably correct, but it was incomplete.

I want to clarify that my comparison between the Russian T-50/Pak-Fa and the French Rafale was strictly an exercise in determining the RCS of the Russian fighter. Obviously, in a real war, a "clean" Rafale is impossible. It has to carry missiles and bombs, which destroys the Rafale's RCS rating.

Anyway, let me continue with my analysis from last year.

From the front, the T-50/Pak-Fa and Rafale are both deficient with a metal-framed cockpit canopy. The Rafale is further deficient with a round nose (not having a shaped nose) and lacks RAM coating. The T-50/Pak-Fa has its own problems of a protruding IRST probe and straight engine inlets (whereas the Rafale engine is 90% hidden).

Also, both the T-50/Pak-Fa and Rafale lack gold-colored transparent cockpit canopy RAM. I have never seen a picture of the T-50/Pak-Fa with gold-colored RAM and I can only conclude the Russians have been unable to develop transparent RAM.

The 0.5m2 RCS for the T-50/Pak-Fa is an average from all perspectives. Last year, I had forgotten to highlight the T-50's superiority to the French Rafale in side-aspect RCS. From the side, the T-50/Pak-Fa has a partially canted airduct, which deflects radar away from the emitter.

Additionally, the T-50's RAM coating provides a much lower RCS in comparison to the French Rafale. The T-50's canted vertical stabilizers further reduce its side-profile RCS. In a real war, the T-50 was always far superior to the French Rafale. The T-50 has internal weapon bays and its RCS was always much lower than a French Rafale in combat.

After considering the T-50's superiority over the French Rafale in side-aspect RCS, I concur with the overall 0.5m2 RCS for the Russian T-50/Pak-Fa.

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Citations:


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Hi,
Please Do Some Research Before Posting...Your Post Are Non Credible And Nonconstructive.
You Really Think THAT---- Only Saw Toothed Edges Are Stealthy ?? Or didn't Know How A Metal frame Canopy Contribute In Over All RCS ??

Learn Basics 1st
ThankYou
 
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Hi,
Please Do Some Research Before Posting...Your Post Are Non Credible And Nonconstructive.
You Really Think THAT---- Only Saw Toothed Edges Are Stealthy ?? Or didn't Know How A Metal frame Canopy Contribute In Over All RCS ??

Learn Basics 1st
ThankYou

Unfortunately he is more knowledgeable than the hundreds of engineers at Sukhoi. And he is right the J-20 mighty drag-queen is super duper superior.
 
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Martian just used Global security and himeself as a citation :lol: And did he actually take the time to put those pictures together? That's sad.
 
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Shaping in stealth aircraft more related to angle of approach than true stealthiness, if you look a flat plate perpendicular to the radar it will send most of the radar back to the transmitter, by tilting the flat plate you reduce signature a great deal, however look that any flat plate at 90 degrees to the radar it will be very visible, at shallow angles of 30 degrees will be stealthy.

now the J-20 flat wings will be very visible depending in the angle the radar looks at them. the flat canted sides are stealthy if the radar is positoned on an angle of 30 degrees with respect them, but on an angle perperdicular to the flat surface of the canted fuselage sides like 90 degrees they are very visible, the flat canted fuselage sides are visible to the radar at 90 degree angles but invisible at shallow angles of 30 degrees or less.

it is not like the J-20 is more stealthy than PAKFA, the J-20 is only more stealthy from certain angles but as visible from others, so the angle of approach is quiet important for the J-20 with respect the radar....

imgp76.gif
 
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So while he nit picks the pak-fa over the slightest of things such as a small IRST probe, he turns around and calls the WZ-10 stealthy even though it has an enormous FLIR and gun hanging off it nose. If it’s Chinese, it’s stealthy no matter what, you see, the WZ-10 is special, it can still be stealthy even with a framed canopy, and FLIR but the pak-fa is definitely not stealthy. :lol:
WZ-10 is a stealthy helicopter. It is stealthy because it has low RCS features not found on most other combat helicopters like an Mi-24.

J-20 is a true 5th generation VLO fighter with RCS comparable to F-22. T-50's RCS is 0.5m2 so it is not a true 5th generation VLO fighter. It is an LO fighter like Silent Eagle (which also has internal bay), so basically it's a Silent Flanker.
 
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