J-21/J-31 Chinese 5th Generation Stealth Fighter

[Yijiuliuer]

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although Airshow China will be open next week, more pix about the details of this AMF or Project 310 model are available....maybe some specs could be revealed as well then... source: china.com

cockpit is like a F22.

 

[J20!]

SAC J-31

 

[J20!]

Double post

 

[ersakthivel]

Don't get taken by simple engine thrust numbers.
It is the weight of the engine for the thrust produced and acceleration to reach the full military thrust that is important.
In this field it is yet to be proven that chinese have surpassed the french or even the indian k-9 standrads despite all the hoopala over the J-20/31.
As it is always easy to hide the engine weight figures and blindly state the thrust figure is a way to confuse people.

Unless one WS sits on the back of JF-17, you will never know.The RD-russian version tech sitting on the back of JF-17 is the proof at the moment of the chinese tech is not as good or as bad as the french.

After 20 years of research , GTRE kaveri produces about 75 kn at sea level.It weighs near 1100 kg or so.

our figure will reach TWR of close to 7 in our first indigenous attempts with no frequency related vibration testing facility and no high altitude test facility.The lack of these facilities resulted in a delay of over 4 years to solve the blade throwing problem.

With snecma collabaration a 90 kn thrust seems possible with further reduction in weight by 100 kgs as per some open source estimates.
So our figure will reach TWR of close to 9 for the jet engine.

It chinese members post these figures it will lead to more informed discussion.
If you want the figures for FRENCH you can ask any body it is 10.

The whole world knows about french engine tech with 2000 mirages exported world wide.

The IAF once anted add extra 126 mirages to it's fleet. So everyone here knows about the level of french engine tech.

Shenyang J-15 - Wikipedia, the free encyclopedia

The J-15 is reported to use different avionics and systems than the Su-33, and uses Chinese-developed technologies, and features various upgrades such as AESA radar, radar absorbent material, MAWS, IRST, composite, and new electronics.[15]

China Signpost believes the J-15 "likely exceeds or matches the aerodynamic capabilities of virtually all fighter aircraft currently operated by regional militaries, with the exception of the U.S. F-22 Raptor"[16], alleging that the J-15 possesses a 10% superior thrust to weight ratio and a 25% lower wing loading than the F/A-18E/F Super Hornet[16].

However, Hu Siyuan of the National Defense University PLA China has said that "the current weak point of the J-15 is its Russia-made Al-31 engines which are less powerful than that of the American F-35 fighter".[17]
This is the reality behind the bluster.

You can go here and see what the chinese are doing

http://airforceworld.com/pla/english...ter-china.html
And more in the above site,
Similarly Indians can put a fancy name on our SUKHOI-MKI and call it our total indigenous product.
but since it is a democracy, such frauds cannot be concealed here.


Shenyang WS-10 - Wikipedia, the free encyclopedia

According to an interview publicised in January 2007 with J-10 pilot Li Cunbao (李存宝), the J-10 had not yet been equipped with the domestic WS-10 engine, because although the WS-10 could match the performance of its Russian counterpart (the AL-31), there was a serious drawback; the WS-10 took longer to "spool up", i.e. there was a delay in reaching the same thrust output as the Russian engine.

WS-10A is reported to have 13,200 kilograms (29,000 lb) of thrust and a 7.5:1 thrust-to-weight ratio, making it comparable to the AL-31F turbofan. The WS-10A was first displayed in public at the 2008 Zhuhai Air Show.
So it is no where near the french tech on rafale.
Infact despite all the hoopla over 13o kn engine ,it is infact in the same level of TWR relatimg to KAVERI-(K-9 version)

With this engine overweight J-20 is a sitting duck once it's stealth cover is blown

Atleast every one knows the k-9 has at last made this much progress concretely and high altitude trials in russia succeeded at this level of thrust.

The GTRE is asking for mating k-9 with tejas.
But no body is interested because these 7 level of TWr is practically not useful in military jet engines of today.

So we are going for a JV with snecma for close to 10 TWR level.

The present model of J-20 that is flying is flying with AL-31 FP russian engine with the TWR level of 7.8
The TWR level the RD-93 engines on the J-31 or whatever it is will be wprse than that.

So flying a few black coloured airframes won't upgrade china to 5th gen plane maker level.

Chinese are in the same league as K-9, even that is suspect as no authoritative figures of weight of the engine is known.

We may reach TWR of 10 with snecma JV.The chinese won't reach that level in the near future.

So indian AMCA if configured properly with an engine of TWR 10 or more it will be more than a match for the chinese ones.

 

[GromHellscream]

well j-31 is already put on display in zhuhai airshow for export

J-31 might enter service before j-20.
We already will have three types of 4th gen fighter..so its better we skip j-10 and better go for j-31 in future when it is inducted

4th gen
F-16
JFT I and II
4.5th gen
JFT III

no need of j-10.when a better option like j-31 is available..still in development bt we can wait.
and as a stop gap measure.go for some serious upgrade in JFT III

Well, whether Pakistan needs extra J10 or not is not a question in big deal considering the fleet affordable.

But what PAF can do at least is to send some of its pilots to train on J10, if with PLAF then it's double win.

So if there is emergency requires in war to cover loss, we can transfer planes from PLAF inventory directly to PAF and get combatable state in short time.

 

[Armand2REP]

 

[Hari Sud]

Do the Chinese feel no shame when reports after reports indicate that Chinese version of f-21 / f-31 are stolen designs. Chinese expatriates to US and elsewhere are in fact spies, sent to steal as much technology as possible. They have been successful. Now the -----oos have their own version of stealth fighters. They stole the design drawings. Building a successful plane from prototype and cram it with electronics and armament is another matter. It will take 10 more years and whole lot more stealing to be done.

Unsuspecting Americans welcomed chinese expatriates in nineties. Hardly did they know that half of them technical spies. Their innocent faces truly are master crooks.

Can China show anything of their own. They have copied the Levi, the Israeli fighter. They have copied Russian SU-27 design. Pakistanis provided them the fundamentals of the American F-16, which they copied into other designs. The only thing they could not copy F-16 properly in the Pakistani JF-16 Thunder, may be it is Pakistani interference or bad design management that a low grade fighter has been produced for the Pakistani air force. Now to improve its battle worthiness, Pakistanis are adding French electronics. A horrible plane will stay horrible.

Back to the Chinese posters of this forum. All of you stop gloating about China's success. It is somebody else's technology you are gloating about.

US would soon change focus. They would protect their secrets same way they protected against USSR. Then you would have hard time to steal.

 

[rockdog]

Do the Chinese feel no shame when reports after reports indicate that Chinese version of f-21 / f-31 are stolen designs. Chinese expatriates to US and elsewhere are in fact spies, sent to steal as much technology as possible. They have been successful. Now the -----oos have their own version of stealth fighters. They stole the design drawings. Building a successful plane from prototype and cram it with electronics and armament is another matter. It will take 10 more years and whole lot more stealing to be done.

Unsuspecting Americans welcomed chinese expatriates in nineties. Hardly did they know that half of them technical spies. Their innocent faces truly are master crooks.

Can China show anything of their own. They have copied the Levi, the Israeli fighter. They have copied Russian SU-27 design. Pakistanis provided them the fundamentals of the American F-16, which they copied into other designs. The only thing they could not copy F-16 properly in the Pakistani JF-16 Thunder, may be it is Pakistani interference or bad design management that a low grade fighter has been produced for the Pakistani air force. Now to improve its battle worthiness, Pakistanis are adding French electronics. A horrible plane will stay horrible.

Back to the Chinese posters of this forum. All of you stop gloating about China's success. It is somebody else's technology you are gloating about.

US would soon change focus. They would protect their secrets same way they protected against USSR. Then you would have hard time to steal.

This is the typical LOSER's mindset, even don't need to debate...

 

[Hari Sud]

This is the typical LOSER's mindset, even don't need to debate...

Show me anything in China which is not either stolen from US or Russia.

 

[Armand2REP]

Show me anything in China which is not either stolen from US or Russia.

They haven't stolen much of anything from the US they can use. Molding the front of an aircraft to look like a US stealth fighter is hardly stealing when they don't understand how it fits the whole. The dimensions of it are easy enough to get. The materials, engines and avionics used are far more important and in that they are far behind.

 

[ersakthivel]

That's because you are comparing PAKFA to YF-23. PAKFA is not a copy of any aircraft. Actually, as far as I can tell, I am not a big fan of "copy of this copy of that" BS. This includes Chinese aircraft.

PAKFA is a complex body and so is the YF-23. Wave behaviour on both aircraft will be different. According to Russia, PAKFA is not as stealthy as the F-22. So, YF-23 could be even more stealthy than PAKFA.

The point is all 3 are stealth aircraft. Which of these is more stealthy may not even matter after a certain threshold is reached. We don't know what is this threshold for aircraft like F-22, J-20, PAKFA, F-35 or J-31. There may be no difference between a F-22 detected at 20Km and a PAKFA detected at 40Km. At this range the OLS may detect aircraft from further away than radar.

What I am trying to say is achieving stealth by a few additional degrees won't matter.

But this does not support my point on which aircraft is more stealthy, F-35 or J-31. This is simply because I don't know and I know for a fact that these so called experts also cannot tell that for sure. The best that they can tell is both F-35 and J-31 are stealth aircraft, the same as I claimed. Especially considering they still haven't properly estimated the RCS levels of older aircraft like SR-71, F-117 and B-2.

The thing is radar shaping isn't the only parameter to stealth. Even materials used contributes to stealth. We have an extremely basic level of knowledge on shaping using open source materials and literally no information on materials. So, it is impossible even for people with PhDs and decades of experience to be able to talk about it without having worked in these fields, eg: Carlo Kopp. The so called lumps and bumps disadvantage may not even be a real factor.



I am quite sure the F-35 requirement did not consider J-31. As a matter of fact, F-35 could be a much more heavier and a more capable aircraft than the J-31 or the planned AMCA due to the weight and fuel differences. F-35 is afterall a much more capable platform than F-15 in certain aspects like empty, loaded and MTOW weights. Even internal volume for electronics along with the extra 2 tons of fuel. J-31 could be in the Rafale class.

SOmehow you have concluded that J-21 with horrible RD-93 engines are in rafale class.
Just by seeing the picture!!!!!!!!!

But despite all explanations, and opensource news
You are always convinced that LCA will always be below the mig-21 bison class as per your opinion!!!!!!!!!!!

There may be no difference between a F-22 detected at 20Km and a PAKFA detected at 40Km. At this range the OLS may detect aircraft from further away than radar.

Since without targeting X band radars there is no possible use in detection at 40 kms according to your own argument.
And even if detected at 40 km there is nothing much the enemy fighter can do,according to your own arguments,
Then what is the use of detection through OLS?Knowing you are about to be shot down?

http://defenceforumindia.com/forum/...ounter-fifth-generation-stealth-fighters.html

Post by W.G.Ewald. quoting

http://www.airforce-technology.com/features/feature128011/

The availability of information on counter-stealth technologies remains low, but it's clear that adaptations of generations-old radar technology have the potential to turn the invisible visible.

Very high frequency (VHF) and ultra high frequency (UHF), pioneered in the 1940s, is still used today for long-range aerial surveillance. These frequencies, as explained by Arend G. Westra in a 2009 issue of Joint Force Quarterly, can confound stealth techniques by operating on decimetre to metre-long wavelengths.

The meeting of wavelengths between radar and aircraft causes resonation between the two, significantly raising an aircraft's reflection in the radar spectrum, making it much more visible. VHF radar has been incorporated into the Russian military's 1L119 Nebo SVU, its first VHF-band active electronically steered array (AESA); although detailed analysis of this vehicle-mounted array, Russian sources report it has achieved excellent results in spotting stealth aircraft.
"Adaptations of generations-old radar technology have the potential to turn the invisible visible."

Passive radar is another well-established, relatively inexpensive technology that has potential against LO aircraft. This system uses multiple transmitters of opportunity to collate data, estimating aircraft positions by calculating the intersection of the receiver-to-target bearing and the bistatic range ellipse. In the past, these estimates have been too inaccurate to be useful, but modern advances in signal and digital processing, along with the availability of sophisticated, low-cost hardware, make passive radar a viable way to detect stealth targets. Passive radar systems in the defence market include Lockheed Martin's Silent Sentry passive coherent location (PCL) system.

The game-changing advance for passive radar technology will be the ability to identify targets as well as track them, allowing passive radar to integrate with surface-to-air missile defence systems.

While the concurrent development of the latest generation of stealth-enabled fighters constitutes an arms race in itself, this race sits within a wider technological contest between stealth and counter-stealth technologies and techniques. Governments around the world are pouring investment into stealth aircraft development programmes, but it remains to be seen if these costly paragons of modern military hardware will end up undone by the evolution of comparatively modest radar systems.

http://www.airforce-technology.com/features/feature128011/feature128011-2.html


It is these UAVs that are going to give target co ordinates of 5th gens to any other aerodynamically efficient 4th gen like RAFALE or TEJAS with their massive weapon load capability compared to punny load of 5th gens.

With evolved missile approach warning system they can dodge the fewer number long range BVRs from 5th gens with ease.
So unless you have matching engine TWR,avionics, radar you cannot hide anywhere.

So simply floating some black airframes like J-20 and J-31 with decades old AL-31FP and RD-93 engines and claiming that you are world beating 5th gen stealth makers the CCP can fool the censored news reading 1 billion chinese people ahead of presidential transition.

A 5th gen plane must be 5th gen in all techs engine -TWR ratio,engine reliability,asea radar,avionics.
Everyone knows J-20/31 is not at that stage.The chinese are yet to mount their own engine on JF-17.
Claiming they are true blue 5th gen and you equating it to all other stealth fighters is HILLARIOUS!!!!!!!!!


You and J-20 once said that Lca is inferior without canards, despite all my attempts to explain the role of cranked delta aka F-16XL.

According to you,Canards are have no rcs issues, with canards J-20 can be just as stealthy.All moving control surfaces like canards are so important for agility.

Then why were the canards dropped on J-31??? I really look forward to yours and J-20's explanation for this interesting issue.They don't want the agility of canards in J-31? Mystery to me.

 

[ersakthivel]

http://defenceforumindia.com/forum/...ounter-fifth-generation-stealth-fighters.html

LURKER BABA's post no-6

So what is the point of fielding 5th gen inefficient stealths?If china can track and shoot them ,pretty much everyone can.Isn't it?
Then the whole concept of stealth is not cutting edge anymore?
Are only the chinese capable of tracking down and shooting the stealths?While indians and others can't?

 

[ersakthivel]

Unable to copy it, China tries building own jet engine | idrw.org

some report about the chinese engine trouble.

 

[GromHellscream]

Under current technologies, it needs a lot of stuffs in form of net to track and shoot a stealth fighter in relative security range, thus that's a big complicated system that can't be deployed everywhere. Even countries like China and Russia can only afford such systems in the limited key nodes in their vast territory, like capitals, heavy industrilized areas and nuclear devices.

But the fighters are much more maneuverable in nature, so that they always hold the initiative to attack or flee. In reality, ground airdefence systems are always in a passive role when dealing with the easily tracked Gen.4 fighters, let alone VLO fighters. Ground airdefence is the second choice when you don't have much confidence in capturing air-superiority against a strong enemy like US. That's why Soviet, Russia and China still devote much resources in such systems though it's less efficient in tactics while US make it a less important role in their doctrine. It's better than nothing.

Another issue is that it's very unaffordable in economics aspect to defend VLO fighters by such complicated systems. For a strike group consists of 4 Fxx which costs around 1-2 billion USD, you need bring in a huge system several times more in cost. Someone expert in China once caculated the cost to build a basic deterrent against VLO threats merely to cover its coast part, and reached a result of 200 billion dollars. The US also understood this point very clearly and once tried to mislead its rivals devoting their main resources in the construction of track nets. But no one bought this theory, in contrast they focused on studying F22's counterparts. If you heavily rely on such systems and lack of your own VLO fighters, you will be bankrupt much earlier than your enemy in an arm race.

 

[J20!]

Project 310's display at Zhuhai:

 

[ersakthivel]

Under current technologies, it needs a lot of stuffs in form of net to track and shoot a stealth fighter in relative security range, thus that's a big complicated system that can't be deployed everywhere. Even countries like China and Russia can only afford such systems in the limited key nodes in their vast territory, like capitals, heavy industrilized areas and nuclear devices.

But the fighters are much more maneuverable in nature, so that they always hold the initiative to attack or flee. In reality, ground airdefence systems are always in a passive role when dealing with the easily tracked Gen.4 fighters, let alone VLO fighters. Ground airdefence is the second choice when you don't have much confidence in capturing air-superiority against a strong enemy like US. That's why Soviet, Russia and China still devote much resources in such systems though it's less efficient in tactics while US make it a less important role in their doctrine. It's better than nothing.

Another issue is that it's very unaffordable in economics aspect to defend VLO fighters by such complicated systems. For a strike group consists of 4 Fxx which costs around 1-2 billion USD, you need bring in a huge system several times more in cost. Someone expert in China once caculated the cost to build a basic deterrent against VLO threats merely to cover its coast part, and reached a result of 200 billion dollars. The US also understood this point very clearly and once tried to mislead its rivals devoting their main resources in the construction of track nets. But no one bought this theory, in contrast they focused on studying F22's counterparts. If you heavily rely on such systems and lack of your own VLO fighters, you will be bankrupt much earlier than your enemy in an arm race.

All stealth fighters are optimized for x band radar waves only. They can be detected using VHF and L band. The problem is since x band radars were used till today for targetting the not much tech effort has gone into L band and VHF , UHF band for this purpose. In future it will be done. ANd no matter whatever the cost defences against stealth will be built one day because 5th gen x band stealths are going to proliferate through out the world.

 

[GromHellscream]

All stealth fighters are optimized for x band radar waves only. They can be detected using VHF and L band. The problem is since x band radars were used till today for targetting the not much tech effort has gone into L band and VHF , UHF band for this purpose. In future it will be done. ANd no matter whatever the cost defences against stealth will be built one day because 5th gen x band stealths are going to proliferate through out the world.

First, the techonology for chasing VLO fighters is not mature nowadays, you also agreed on that; Thus under current technologies, it's very cost expensive to develop such system and still get unsatisfied results against VLO fighters.

Second, how many years should we wait until its maturity, 10 years, 20 years or even longer? If VLO fighters could dominate the sky for another 1 or 2 decades, they have already fullfill its target in history. When counter measure has been developed, there might be another generation fighters in shape already.

Third, countries who have the capabilities to design counter measures, if not out of expectation, are all powerful ones on world stage. They need develop the counter measures to their own VLO fighters first. Even they succeed someday, there might be common interest among them even they are somekind rivals, so that the technology is only shared among elite clubs who already have it, just like the Nuclear Club and Restrictions on Long Range Missile Exportation. So that VLO fighters can still keep its secrets to outer world for a much long period.

Fourth, i don't think VHF and L band radars are adequate or even necessary to be part of the solutions. Many limts lie there.

 

[LTE-TDD]

Show me anything in China which is not either stolen from US or Russia.

Who are you? Why we need to show you? You are too joulous, right? Who care you?

 

[lcatejas]

Sacchayi bahut dhuk dayi hoti hai ....

 

[ice berg]

Avic Promotes J-31 As An Export Fighter

As much as the resources wielded by the Chinese state aerospace industry impress outsiders these days, few could have expected that one of the companies in the sector would want to produce a stealth fighter on its own account.

But that is just what Shenyang Aircraft wants to do. Equally surprisingly, the Chinese air force is turning its nose up at the result. What looks like a thoroughly modern stealth fighter is apparently not good enough to serve as China's next medium-weight combat aircraft.

After three evidently staged appearances of the real aircraft this year, Avic displayed a model at Airshow China in Zhuhai last week, displaying the fighter that is unofficially called the J-31 and known to come from Shenyang. The aircraft is being developed "for the international defense market," says Avic.

The model was labeled as a concept fighter, but it showed few if any differences from the real aircraft that appeared first under wraps on a truck in June, then being pulled around an airfield in September and, finally, on Oct. 31, in the air, prominently numbered "31001" and possibly making its first flight. It is clear, then, that the project has transcended the concept stage.

The aircraft has been designed to deliver a highly stealthy configuration at low cost, with a heavy weapons load capability over a wide combat radius, says Avic. The model is a single-seat, twin-tail, twin-engine aircraft with a high wing, like the real aircraft seen in unattributed photographs on the Internet. As described at the show, the fighter has a typical takeoff weight of 17.5 metric tons, is 16.9 meters (55.5 ft.) long and 4.8 meters high with a wingspan of 11.5 meters.

The aircraft that flew last month has two Klimov RD-93 engines, which project engineers do not regard as sufficiently powerful, industry executives say. As fitted to the JF-17 (or FC-1) single-engine export fighter from Shenyang's rival, Chengdu Aircraft, the RD-93 produces 19,000 lb. thrust. Regardless of the RD-93's power, Shenyang needs a Chinese engine if it is to avoid Russia holding a veto over J-31 sales. Judging from photographs of the prototype, the nacelles may be designed for engines larger in diameter than the RD-93, a derivative of the MiG-29's RD-33. The alternative may be the reported WS-13 Taishan from the Guizhou plant of propulsion specialist Avic Engine.

Avic says the J-31 has a combat radius of 1,250 km (780 mi.) on internal fuel or 2,000 km with external tanks. Maximum speed is Mach 1.8, takeoff distance is 400 meters and its landing distance 600 meters.

"Operational effectiveness will be higher than current or upgraded fourth-generation fighters or almost equivalent to typical fifth-generation," says Avic. The reference to fifth-generation aircraft presumably indicates the Lockheed Martin F-22 and F-35.