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J-20 Supercruise speed

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Nope...No assumptions there.
You can certainly think whatever you like. Simply know there are people that work closely with CAC in China that share the same view.
 
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yeh absolutely right captain....:police:

its way too power in maneuverability, stealth and most importantly IMAGINATIONnnnnnnnnn....
Always funny to hear Indian trolls demonstrate their intelligence.
 
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remember that RCS advances have decreasing gains and asymptotically approach a fixed value of minimal detection distance, while maneuver is essentially unlimited except by physiology (and especially instantaneous turns). however i'm still suspicious of 3d thrust vector, it seems far too heavy.
I've talked with huzigeng on that point (he's the guy that first leaked the J-20 two years before it was seen). He stated some guy working at the 606 institute specifically leads a team to reduce engine noise and nozzle signal emission. He further stated that 2D TVC similar to F-22 will be out of the question, as the Chinese air force wants to pursue as agile of a plane as possible.

Personally I am a little concerned about how much sacrifice they are willing to make in terms of RCS for better manoevurability and supercruise. I understand it's a compromise when you don't have the research as the Americans do in VLO, but that doesn't do much good when the enemy can see/react faster than you through better sensor fusion and stealth.
 
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That is another dangerous and quite ignorant assumption. With WS-15 3D TVC nozzle, all moving tail and canard, the J-20 can exceed F-22's manoevurability. It is designed from the start to be more agile than the Raptor, with better supercruise ability.
that its so true brother... the J-20 will be king of the sky in the near future...:china:
 
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Chengdu did very well in designing the aerodynamics of J-20, now the answear to how fast it can supercruise comes to the engine they going to use on that beast.

just one day after Chinese New Year 2.Fed.2011, there was an anonymous guy put a post claim that WS-15 is successfully finalized. (the guy claimed he worked for related department, at the Chinese New Year's eve party, a person in uniform from the top gave a keynote speech appraising all the hard works and milestone acheivements, on one occassion he mention the 'next generation engine' had been successfully passed the 2000hours ground testing phase, and had mention the max thrust of the 'next generation engine' is over 18,000kgf !)

I'm quite speculative about 18,000kgf max thrust! however, when FC-1,
J-10, WZ-10, J-10B, J-xx were all highly rated rumors, they all came out true with a bit more surprises. So I start to seriously consider what that anonymous guy's claim.

the link is here:http://club.china.com/data/thread/272425507/2722/35/14/3_1.html
can anyone translate this into english, Im not very sure about my translation skills``:P
 
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You can certainly think whatever you like. Simply know there are people that work closely with CAC in China that share the same view.
Are YOU a member of that group? If not, then what you claimed back on post 41 is as equally presumptuous as by those who you accused of being presumptuous. Of course, you can certainly think whatever you like.

In flight controls, it is not enough to have flight controls surfaces such as wings and stabilators. We need flight control laws. A 'push-pull' rod is a 'hard' law.

FLIGHT CONTROL SYSTEM PUSH-PULL ROD ADJUSTABLE ROD END BEARING ASSEMBLY REPLACEMENT/ADJUSTMENT – continued

We can make the entire mechanical flight control system have variable output for every input. Or we can make it straight 1-1. We can make it so that a single input will produce multiple outputs, like a 'pitch-roll assembly'.

Horizontal Stabilizer Control System (Double Axis)
The control, stick grip movement is mechanically transferred to the left and right stabilizer servo cylinders through the pitch and roll command summing network, the feel assemblies, and the summing network.

Anyway we do it, the entire system, even mechanical, is governed by 'flight controls laws'.

Fly-by-wire flight control systems (FBW-FLCS) are much more dangerous in that we do not have the inherent conservativeness, or built-in restrictions, of mechanical linkages. Those laws are governed by softwares which in turn is affected by the sophistication of the electronics. Badly written flight controls laws can manifest themselves at any time during a maneuver. A set of flight control laws may not even have the engine thrust vectoring capability and leave that capability in the pilot's hands, making more work for the pilot.

Here is a high(est) level outline of the Airbus flight control laws => Airbus Flight Control Laws

Here are a few people talking about their experiences with those laws => Airbus Flight control laws - PPRuNe Forums

It is not difficult to extrapolate from a stable airliner design to a jet fighter whose characteristics includes instability from when it was conceived on paper to see how much more complex the flight controls laws will be at the lower levels. Legend has it that the F-16's first flight was very unofficial in that the test was supposed to be a high speed run but the aircraft's aerodynamics lifted it off the ground. The pilot had no choice but to go along and eventually safely landed the aircraft. That was the first generation analog fly-by-wire FLCS.

The J-20's designers could be deliberately conservative for now. Or they may discover later that certain combinations of rules can send the aircraft into uncontrolled flight and exclude those combinations, making the aircraft less capable than its competitor. We do not know. So it is wise to put aside nationalist fervor and try to learn something.
 
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Supercruise or no, it seems logical to me that the J-20 was designed from day one to be a raptor killer.
 
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Are YOU a member of that group? If not, then what you claimed back on post 41 is as equally presumptuous as by those who you accused of being presumptuous. Of course, you can certainly think whatever you like.
Certainly I am not a member of that group, but that does not mean members of that group do not regularly visit forums in China and keep the public up to date with status of the project. It's not an assumption on my part, but rather a reflection of their views. Surpassing F-22's manoevurability was one of the "hard" requirements the military had imposed early in the process, even at the cost increased signature.

The J-20's designers could be deliberately conservative for now. Or they may discover later that certain combinations of rules can send the aircraft into uncontrolled flight and exclude those combinations, making the aircraft less capable than its competitor. We do not know. So it is wise to put aside nationalist fervor and try to learn something.
That again, is an assumption on your part that they would be unable to program the flight control to exceed its competitor. The project director himself specializes in this field and in addition an entire research faculty at Northwestern Industrial University is devoted to the job. You may wish to dismiss it as mere nationalistic view, but CAC engineers seems to be optimistic after windtunnel tests and simulations.

Like I said before, feel free to think whatever you like, but I rather trust the words of those who work under AVIC 1 than yours.
 
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that its so true brother... the J-20 will be king of the sky in the near future...:china:
No, it will not. Keep in mind that planes such as the J-20 and T-50 are what you build when you don't have the amount of research in low observable technologies and sensor fusion as your competitors. Fast and agile platforms that give better survival rate when your own pilots have reduced reaction time.

Americans will continue to control the sky for years to come.

Supercruise or no, it seems logical to me that the J-20 was designed from day one to be a raptor killer.
Chinese air force wanted a plane that will have a chance against other 5th generation fighters when supported, not some magical "Raptor Killer" as you've put it.
 
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No, it will not. Keep in mind that planes such as the J-20 and T-50 are what you build when you don't have the amount of research in low observable technologies and sensor fusion as your competitors. Fast and agile platforms that give better survival rate when your own pilots have reduced reaction time.

Americans will continue to control the sky for years to come.

I'm interested. Please elaborate.
 
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No, it will not. Keep in mind that planes such as the J-20 and T-50 are what you build when you don't have the amount of research in low observable technologies and sensor fusion as your competitors. Fast and agile platforms that give better survival rate when your own pilots have reduced reaction time.

Americans will continue to control the sky for years to come.


Chinese air force wanted a plane that will have a chance against other 5th generation fighters when supported, not some magical "Raptor Killer" as you've put it.

doesn't matter, RCS reduction asympotically approach a minimum value for detection distance anyways. Your plane doesn't need to be totally invisible, just invisible enough that by the time it can be targetted by fire control radars it can also be visually detected.
 
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