SAC FC-31 Stealth Fighter: News & Discussions

[eachus]

And make they do. The assmptions are more than just assumptions, most of the time they defy physics. In any case the typical assumptions have been: the pak-fa is garbage, the F-35 is cheap, the F-22 is outdated, the Rafale and Typhoon will be swiped from the sky by the might dragon.

your correct! Russian T50 is not stealthy, you can call it Su30 upgrade or whatever you like. Rafale and Typhoon are even not in the same class, let them be.

Now, F22, J20 and F35 are in the top end, J31 looks pretty cool except the temporary engines. T50 follows behind has too much to polish --- right now between 4G and 5G. is that fare?

 

[manqiangrexue]

Gambit, what's the point of bringing up the pilot in a debate about a prototype machine? It's not a debate about whether a Chinese pilot flying this would beat an American pilot in an F-35. This jet's not mature enough to even think about that scenario. If there's a point, what is it? It only exists in Viet logic and my mind doesn't work in that cockroach way so I won't get it.

I said it's impossible to disprove about THIS jet because we only saw it in 4 pictures and it never flew so we don't know enough for anything to be proven or dis-proven about THIS jet. That doesn't apply to all the jets flying in the world. Viet logic AGAIN from you.

Stop it with Viet logic. It's getting tiresome, more so than "Chinese physics" (by the way, I haven't been here for long, but during the time I'm here, I've not seen any Chinese person make claims about physics, only you talking about how other people do this).

Your theory that the changes are due to accommodate different engine design and not genuine improvements is noted. That's an alternate theory to mine and that's all. Don't treat your theories as proven. Don't try to make it like you're right and I'm wrong. It's not possible for that to be proven as it pertains to this jet right now.

Stop telling other people they don't have aviation experience and you do. You don't. You flew jets, and it's not experience designing jets. You are just the same as everyone else. If you designed a stealth jet, tell me the model, then I will acknowledge that you are an expert. If you didn't, then you are just as inexperienced as everyone else.

I'm doing you a huge favor by giving you the benefit of the doubt and saying that I believe you flew jets for 20 years. Even that much is not proven. You didn't show a certificate or any kind of proof. To recap, this is how far away you are from being respected as an expert: 1. You have shown no proof at all that you flew jets for 20 years. 2. Even if we give you the benefit of the doubt and say that it's true, it doesn't mean you have experience in stealth jet design. I know a guy who's dad's a crazy redneck who keeps telling people gruesome stories about his adventures as a US soldier in Vietnam. The crazy part: He's never left Texas before in his life. That could be you.

Oh, and I like how you said you were 100% sure how the PLAAF works. A Vietnamese in America thinks he knows how China's military works and is 100% sure. Never heard such crap before. By the way, all the Americans who thought they knew 100% how the Chinese military worked, have their bones scattered all over North Korea right now.

I never said I'm better at this; I know I'm not. I'm just saying you're not better either and that's difficult for you to swallow because you came in here thinking that having flown jets for 20 ears, everyone would respect you as the guru. It's not happening.

 

[eachus]

You don't think my assumptions are solid? Let's go.

1. J-31 is different from the F-35 from the side view (fact). If they changed it, I assume Shenyang improved it. Otherwise, they would keep the original F-35 configuration. People don't change things to make them worse.

2. J-31 looks like a mash up of the F-22 and F-35 (maybe kinda subjective but I think so). So it seems logical to start with the stolen F-35 plans and generously use parts of the F-22 design to alleviate any short-comings found in the F-35 frame.
Original Post By manqiangrexue

The highlighted is where you are wrong. It is both an assumption and a hope. It is a reasonable assumption because no one want to degrade an existing design. It is a hope because you do not know what entails in designing an aircraft.

The heart of ANY aircraft is not the pilot, who is the brain, but propulsion.

For example...

In a pusher prop job, prop wash produces a twisting force around the fuselage and eventually on the left side of the vertical stab, the pilot must produce a counter yaw with the rudder pedals to maintain straight heading. This effect does not exist with a jet engine aircraft, therefore we have a much greater latitude in designing our fuselage.

Pusher configuration - Wikipedia, the free encyclopedia

What this mean is that even if you copied exactly down to the rivet locations of an existing aircraft but you do not have the comparable propulsion, your copy will not fly, or it will fly like sh1t. Even worse so if you try to 'hybridize' two different designs into one that you hope that you improve.

I am sure the manufacture of Shenyang J31 knows what they are doing.
I deed they avoided the problem 35 has, too fat, too heavy.
the J31 goal is very simple and clear, air superiority for navy and export market.
yes will be low cost mid size fighter. we can see the stealthy is still in priority,
J31 will have a fight with F35 is what their main goal.

Chinese are little different to the west, domestic firm are mostly state owned,
they are competing with each other and also cooperate with each other.
At the time Chendu designed and tested DSI intake on FC1, ShenYang, XiAn
and other companies were already started sharing the technology.
even the engineers they can be shared. That is why Chinese growth these 5G like mushrooms.
Chinese are very efficient in budget and time.


J31 will be around the same size as F35, lighter, slimmer, faster. maybe with smaller
front RCS. if one day J31 vs F35 one to one, they will have a fight. J31 will
have less function than F35. J31 price tab will be a big surprise, can be 25% ~ 30% of F35.

 

[amalakas]

your correct! Russian T50 is not stealthy, you can call it Su30 upgrade or whatever you like. Rafale and Typhoon are even not in the same class, let them be.

Now, F22, J20 and F35 are in the top end, J31 looks pretty cool except the temporary engines. T50 follows behind has too much to polish --- right now between 4G and 5G. is that fare?

I am sure the manufacture of Shenyang J31 knows what they are doing.
I deed they avoided the problem 35 has, too fat, too heavy.
the J31 goal is very simple and clear, air superiority for navy and export market.
yes will be low cost mid size fighter. we can see the stealthy is still in priority,
J31 will have a fight with F35 is what their main goal.

Chinese are little different to the west, domestic firm are mostly state owned,
they are competing with each other and also cooperate with each other.
At the time Chendu designed and tested DSI intake on FC1, ShenYang, XiAn
and other companies were already started sharing the technology.
even the engineers they can be shared. That is why Chinese growth these 5G like mushrooms.
Chinese are very efficient in budget and time.


J31 will be around the same size as F35, lighter, slimmer, faster. maybe with smaller
front RCS. if one day J31 vs F35 one to one, they will have a fight. J31 will
have less function than F35. J31 price tab will be a big surprise, can be 25% ~ 30% of F35.

But apparently the manufacturers of T-50, which by the way have far bigger experience in making planes, apparently do not know what they are doing. Nice logic there mate!

 

[danger007]

your correct! Russian T50 is not stealthy, you can call it Su30 upgrade or whatever you like. Rafale and Typhoon are even not in the same class, let them be.

Now, F22, J20 and F35 are in the top end, J31 looks pretty cool except the temporary engines. T50 follows behind has too much to polish --- right now between 4G and 5G. is that fare?

great development sir.. lolz

 

[antonius123]

But apparently the manufacturers of T-50, which by the way have far bigger experience in making planes, apparently do not know what they are doing. Nice logic there mate!

Maybe limited budget and weak r&d cause that

 

[Kiss_of_the_Dragon]

I don't give a Rat A$$ for any who want to criticize this bird, China should move forward even with handicap, we're unstoppable unless if we give up...but now enjoy some nice artworks

 

[doidoi2]

But apparently the manufacturers of T-50, which by the way have far bigger experience in making planes, apparently do not know what they are doing. Nice logic there mate!

I dunno, I wanna like the T-50, but a casual glance at pics shows the level of worksmanship leaves much to be desired. The ill-fitting panels, various bumps and rivets. Compare that to the J-20, you can barely see the seams. In fact the seams are fitted so perfectly that people actually debated whether or not the J-20 had a weapons bay when it first came out.

That said, I do have confidence that the Russians will fix things when the final version comes out. The Russians are still ahead of the Chinese in many areas of Aerospace. It's tough to beat the decades of Soviet Aerospace experience that the Russians have.

 

[BanglaBhoot]

By James Hardy

China’s defense industry seems to be up to its new trick of unveiling its latest toy when a senior U.S. official visits Beijing.

Following the playbook established in January 2011 when Chengdu’s J-20 stealth fighter had its maiden test flight just in time to overshadow the visit of then-Secretary of Defense Robert Gates, rival aerospace firm Shenyang Aircraft Corporation (SAC) accidentally-on-purpose allowed some high-definition images of its own fifth-generation fighter jet to appear on the web over the weekend. Coincidentally, current Pentagon chief Leon Panetta had just kicked off an Asian tour that included a stopover in Beijing.

Secretary of State Hillary Clinton may have been on the end of a similar welcome when she visited China in early September. Grainy images of the PLA Navy’s latest destroyer, the Type 052D, turned up on the web along with a Global Times story just as CCP heir apparent Xi Jinping vanished for two weeks.

In truth, the Shen Fei (or Falcon Eagle), as SAC appears to have nicknamed the aircraft judging from its tail markings, is less of a mystery than the J-20 was when it emerged. As J. Michael Cole noted here in August, a Shen Fei-shaped airframe covered in camouflaged webbing enjoyed a well-publicized tour of China’s road network in June on its way from Shenyang to the China Flight Test Establishment at Xian-Yanglian Airbase, Shaanxi Province.

Now the wraps are off, it’s clear that the Shen Fei is based on a design dubbed the F-60 that has been doing the rounds as a model aircraft since at least September 2011. Described by IHS Jane’s aviation expert Robert Hewson as an “F-35-sized F-22”, it is much closer in platform than the J-20 to these two Lockheed Martin designs, which are fulfilling the U.S.’ next-generation manned fighter requirements.

Some argue that the Shen Fei is a result of some pretty serious cyber-espionage, which may explain why Panetta brought up "the growing threat posed to both economic and security interests by cyber intrusions" in his meeting with Chinese Defense Minister General Liang Guanglie on September 18. And although Western intelligence officials regularly imply that Chinese technological advances are aided by the dark arts, a glance at the F-22, F-35, Russia’s T-50 PAK FA and Japan’s ATD-X show that stealthy fifth-generation fighters tend to have a similar platform.

The Shen Fei and J-20 continue this trend, but the complexities of modern fighter aircraft design and production suggest that there’s still plenty of work for both SAC and Chengdu to do before they can compete with Russia and the West. As Lockheed Martin has found out with the both the F-22 and the F-35, fifth-generation fighters are hard to get right: the F-22 was recently grounded with a system problem that was causing pilots to black out, while the F-35 is behind schedule, over budget and testing the patience of the U.S. Air Force to the limits.

The key challenge facing Chinese designers is not in coming up with a stealthy platform, but the systems that go inside it. These include electro-optic sensors and an AESA fire-control radar – a generational jump in technology that comes as standard on F-35s and F-22s; stealthy coatings; and reliable engines. The latter are a particular bugbear for China, which has for years relied on Russian technology to power its fast jets. Many Western observers believe the Shen Fei is powered by two Russian-sourced Klimov RD-93 turbofans, reinforcing perceptions that this particular weakness is holding China back. The fact that the same images show that these engines appear to be ill-fitting suggests that Shenyang may be following the lead of Chengdu, which is believed to be trying out a number of different engines on the J-20.

But in other ways the Shen Fei is different from the J-20. Its unveiling did not include a test flight or state media coverage and it is not painted in PLA Air Force colors or markings. That suggests that it may be a company-financed project and would also corroborate reports that Chengdu beat SAC with the J-20 to provide the PLAAF with its fifth-gen fighter. Then again, the two platforms’ differing size also supports assertions that they could have different roles: the J-20 a long-range strike aircraft, with the Shen Fei acting as an air-superiority fighter.

As with most indigenous Chinese military programs, much is shrouded in mystery and speculation. The Shen Fei’s twin-wheel nose gear has led some to argue that it could be a future carrier fighter (on account of the reinforced undercarriage that most carrier-based aircraft are fitted with). Alternatively, it could be that SAC has just borrowed the technology from the Sukhoi Su-33-derived J-15 that it is building for the PLA Navy.

Either way, the Shen Fei’s appearance after years of rumors, scale models and surreal sightings has confirmed one thing: that China-watching occasionally has its benefits. Given Beijing’s punitive attitude to official secrets and the understandable concern around the Asia-Pacific region at its myriad military programs, it’s a relief that this 21st century version of Kremlinology pays off, at least some of the time.

China’s New Stealth Fighter Gambit | The Diplomat

 

[Esc8781]

I dunno, I wanna like the T-50, but a casual glance at pics shows the level of worksmanship leaves much to be desired. The ill-fitting panels, various bumps and rivets. Compare that to the J-20, you can barely see the seams. In fact the seams are fitted so perfectly that people actually debated whether or not the J-20 had a weapons bay when it first came out.

That said, I do have confidence that the Russians will fix things when the final version comes out. The Russians are still ahead of the Chinese in many areas of Aerospace. It's tough to beat the decades of Soviet Aerospace experience that the Russians have.

Umm.. because its black.

 

[doidoi2]

Umm.. because its black.

ummm... no. Look at the smooth texture of the underbelly.

 

[gambit]

Your theory that the changes are due to accommodate different engine design and not genuine improvements is noted. That's an alternate theory to mine and that's all. Don't treat your theories as proven. Don't try to make it like you're right and I'm wrong. It's not possible for that to be proven as it pertains to this jet right now.

That is no mere 'theory'. That relationship is a fact.

Evidence 1...

Airframe and Powerplant | Aircraft Mechanic | Schools | A&P License

There is a reason why we have an 'airframe and powerplant' licence. Can you finger it out?

Evidence 2...

icas-proceedings.net/ICAS2000/PAPERS/ICA6103.PDF

Introduction

Propulsion airframe integration presents unique challenges to the development of an aircraft system. Many of these challenges arise from the fact that the airframe integration issues involve major interfaces between aircraft and engine manufacturers. Good working relationships [1,2] between these two entities is essential for a successful business venture.

Evidence 3...

NASA - Small Aircraft Propulsion: The Future Is Here

The new GAP engines will change all of that, along with our ideas about what general aviation propulsion systems can be. With their smooth, quiet operation, they provide comfort never before enjoyed in general aviation light aircraft. New engines are crucial to truly new airplane designs. The GAP engines are bringing about a revolution in light aircraft affordability, ease of use, and performance.

Evidence 4...

U.S. Supersonic Commercial Aircraft: Assessing NASA's High Speed Research Program

This chapter concentrates on technology and systems integration...

Achieving this goal requires overcoming adverse interactions involving the pilot, airframe, propulsion system, and flight control system. This report refers collectively to the last three as the APSE (aero/propulsive/servo/elastic) system.

Evidence 5...

Airframe-Propulsion Integration for Future Aircraft Systems

Specific airframe-propulsion integration problems for mixed mission aircraft are discussed...

In other words, it is intellectually hazardous to divorce propulsion from overall design. Even ship hull designs are affected by flow dynamics and a ship do not need to move to stay afloat while an aircraft must move in order to stay airborne. So what make YOU such an authority that you can perform such a technical divorce and make assumptions? I challenge you to dispute even just one of the above five sources.

If a request for proposal (RFP) from the customer seemingly demand a propulsion method/technology not yet available -- YOU design that new method/technology. Which is what Lockheed did with the J58 engine in order to meet the SR-71's RFP.

For the above example, which engine is going to have a much higher throttle cycling and therefore demand a much more responsive engine? The fighter aircraft engine, of course. And how many cargo aircrafts out there that look like an F-4 or an F-15? None.

For the above example, both engine TYPES share a common bond -- multiple fan stages. But look at their radical differences beyond that common bond. Look at the human figures included for scale. Now guess which engine design is for a lumbering and steady state cargo airframe.

You should not make assumptions on an airframe without considering its propulsion: real, potential, or interim.

This is why it is so fun to debate you Chinese boys. And given my experience, a little bit sadistic, I admit...

 

[manqiangrexue]

Ah, you're using Viet logic quite copiously I see. Your diagrams, once again, while true, have no point. No one ever questioned the fact that engines on a fighter are designed differently from a cargo jet.

The point is that there are many changes on the J-31 from the F-35. Do those changes reflect adaptations to different engine layout or are they genuine aerodynamic improvements? Or both?

Your diagrams address none of that. This is a classic example of hiding behind facts. Someone too stupid to understand them might be fooled into thinking that you took a logical approach and supported it with evidence. But someone who looks a little deeper sees you just submitted 2 pages of oral diarrhea.

If you really think you're making good points, it's probably because you're way too old for debating anyway. Pills time, gramps.

Your "experience"?? The ones you claim to have but don't prove? There's a lot more liars in America than air force pilots so statistically speaking, if you don't provide a certificate, you're the former.

I really like how you used the word, "sadistic". You know what it reminded me of? It reminded me of what the US did to Vietnam in 1969. And when you hear "sadistic", what word comes to mind? Masochistic! And that's you for joining the air force that did this to your country (if, that is, in fact what you did, which is quite questionable without any kind of evidence).

 

[Esc8781]

I am sure the manufacture of Shenyang J31 knows what they are doing.
I deed they avoided the problem 35 has, too fat, too heavy.
the J31 goal is very simple and clear, air superiority for navy and export market.
yes will be low cost mid size fighter. we can see the stealthy is still in priority,
J31 will have a fight with F35 is what their main goal.

Chinese are little different to the west, domestic firm are mostly state owned,
they are competing with each other and also cooperate with each other.
At the time Chendu designed and tested DSI intake on FC1, ShenYang, XiAn
and other companies were already started sharing the technology.
even the engineers they can be shared. That is why Chinese growth these 5G like mushrooms.
Chinese are very efficient in budget and time.


J31 will be around the same size as F35, lighter, slimmer, faster. maybe with smaller
front RCS. if one day J31 vs F35 one to one, they will have a fight. J31 will
have less function than F35. J31 price tab will be a big surprise, can be 25% ~ 30% of F35.

Its "chubbiness" is good for it self, going simple ever heard of Area rule?

To minimize the supersonic drag coefficient, the change in area along the length of the aircraft should be smooth (example, having a tubular fuselage with a pair of wings jutting out of the sides is much worse than having a fuselage that narrows along the chord of the wing).
as long as the area along the lenght varies smoothly, you're good. The "fat" cockpit bulge and flattening over the wing gloves is why the B-1B has a cruise speed farther into the transsonic regime than any other bomber. The F-35 tries to conform to Mach-Area rule by swapping lateral expansion for vertical contraction. Take a look at a Boeing 747.

 

[Esc8781]