who are these stupid experts,fc-1 is inspired by the cancelled mig-33, j-11 from su-27 and j-10 is from lavi.this is correct. moreover these jets are not exact copies but rather these are modified variants. nevertheless the chinese aviation industry has come a long way.j-20 is its own design. china started by making copies and in a way it has developed its aviation industry.if copying helps a country develop itself into a robust aviation giant then i am all for it. i hope india follows such a model
J-20... The New Generation Fighter III
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who are these stupid experts,fc-1 is inspired by the cancelled mig-33, j-11 from su-27 and j-10 is from lavi.this is correct. moreover these jets are not exact copies but rather these are modified variants. nevertheless the chinese aviation industry has come a long way.j-20 is its own design. china started by making copies and in a way it has developed its aviation industry.if copying helps a country develop itself into a robust aviation giant then i am all for it. i hope india follows such a model
Well, as far as I learned, the J-10 is not inspired by LAVI. It has more to do with the cancelled J-9. ...As for the Indians, unfortunately, their problem lies in their weak, weak industrial base, yet they love to practice something in our history: The Great Leap Forward.
And they do that not only practically, as a state (their mil. industries), but also (and even more so) mentally, as forum warriors...
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PlaWolf has a point. Quit the useless Su-35 B.S. and get back on topic folks! Next violator will be punished with infractions and then a week long spring break vacation!
Engineer
Major
No matter how light 3D TVN is, it still going to be heavier than an equivalent engine without TVN. For there to be TVN, there must be added weight. This implies decrease in thrust-to-weight ratio, meaning a decrease in performance.
In that same article, they clarified what produces that increase in thrust:
Flight Global said:
Like I said previously, they are referring to variable exhaust nozzle. More specifically, a variation where the area of exit can be adjusted independently of throat area. It is unrelated to TVC which purpose is to give thrust an angular component.
Your own quotation contradicted your claim.
That 40kg is a weight penalty, and it is pretty significant since every single kg matters on an aircraft. On top of this, that 40kg is only for one engine, which means the total increase in weight would be 80kg for two engines.
Keep in mind that EJ200 is only a medium thrust engine. For engine such as the F-119 which has a larger diameter and twice the amount of thrust, the weight penalty is going to be higher because the nozzle is bigger and needs to be sturdier.
A 14-17% decrease in thrust is a significant decrease in performance. Being heavier AND reduce engine thrust while marginally reduce drag is an overall decrease in performance. You must be assuming Chinese engineers as brain damaged if you think they will sacrifice such performance for TVC.
A concentric TVN is only better than a flat one in that the former doesn't reduce thrust. The TVN is still going to incur additional weight, reducing thrust-to-weight ratio of the engine.
Again, irrelevant.
J-20 has conventional aerodynamic control surfaces and is not a tailless aircraft. Additional of TVN will not bring about enhance stealth for the J-20, because control surfaces will not be removed for the sake of silliness. In fact, no manned aircraft currently employing TVN removes vertical fins. As far as stealth is concerned, J-20 is already stealthy as it is, and does not require removal of vertical fins to further decrease RCS.
EJ200 has weight penalty -- 40kg according to your own article. Just because the penalty isn't as severe as the one on F-119, that doesn't mean it does not exist. All TVN has weight penalty as result of increased mechanical complexity of the nozzle. Weight penalties imply decrease of thrust-to-weight ratio, which decreases the performance of the engine and offsets advantage of reduction in trim drag.
As long as WS-15 is ready on time, J-20 would meet criteria of being a 4th generation fighter aircraft. TVN isn't a requirement for J-20, and there is no reason why J-20 has to have TVN before being delivered to PLAAF by 2018.
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MiG-29
Banned Idiot
The Typhoon is designed to provide the pilot with "care free" engine handling to reduce workload, and this would not change with the introduction of thrust vectoring, says Eurojet engineering director Wolfgang Sterr. The TVN has several degrees of freedom, enabling it to deliver control forces in pitch and yaw, while optimising the throat ("A8") and exit ("A9") areas to suit flight conditions, for example in supersonic cruise where a divergent configuration is required to accelerate the gas flow for increased thrust.
"It is not possible [to do this] for the existing nozzle, which has a fixed schedule between A8 and A9, optimised for certain conditions only," says Sterr. "With the TVN you can reduce the fuel burn and life cycle costs as well, in certain parts of the envelope," he adds.
In the standard EJ200 a cam controls how the throat and exit areas are adjusted relative to each other, but in the TVN the exit can be ovalised and therefore varied independently from the throat, using the same actuators that are required to redirect the thrust. "You get this flexibility almost for free," says Sterr
You need TVC nozzles to achieve it, in fact they say
It is not possible [to do this] for the existing nozzle, which has a fixed schedule between A8 and A9, optimised for certain conditions only," says Sterr. "With the TVN you can reduce the fuel burn and life cycle costs as well, in certain parts of the envelope," he adds
and he adds the same actuators that give TVC, in other words unless you have the ability to control the nozzles feathers
but in the TVN the exit can be ovalised and therefore varied independently from the throat, using the same actuators that are required to redirect the thrust.
So unless they have TVC nozzles the net increase will accur
later they say less drag more thrust of course increase even further speed
TRIM-DRAG REDUCTION
The TVN's ability to enable the engine to produce thrust more efficiently, coupled with the trim-drag reduction, results in a "double win", says Eurojet's Price.
but look i am not going to waste more time with you, J-20 will get gains by using TVC nozzles in stealth and supercruise, if you are not satisfy you can contact ITP and tell them your opinions, so far i am not going to answer you any more about facts a Engine manufacturers claims in their webpage; Thrust vectoring increases stealth, supercruise, STOL, safety, poststall ability, range and burns less fuel etc etc, flat nozzles will mean a higher weight penalty true, but will mean lower IR signature, and saw teeth edges as on F-22` nozzles will mean lower RCS and lower supersonic trim drag and higher roll rates.
In fact thrust vectoring increases high AoA controlability meaning an expansion of J-20`s AoA Post-Stall Flight
The most spectacular benefit of Thrust Vectoring, although
possibly not the most important, is the fact that it can exert
an active control of an aircraft while the main aerodynamic
surfaces are stalled, hence not suitable for control, and this
opens a whole new domain of flight conditions where flight
used to be unthinkable
here it meantions clearly the true advantages
The use of Thrust Vectoring permits the aircraft to hold
stationary flight in an area of the envelope where
conventional controls are not sufficient.
In the Altitude/Mach-number envelope, Thrust Vectoring
permits an extension of the envelope in the low speedmedium
height region. In the Altitude/Mach-number/Angleof-
attack envelope, Thrust Vectoring permits operation at
much higher values of Angle of attack
Once the Thrust Vectoring system has been sufficiently
validated, it will be a primary control for the aircraft. This
Foreplane
Rudder
Leading Edge Flaps
Slats
Nozzles
11-5
means that it will allow a gradual reduction of existing
conventional aerodynamic control surfaces such as
horizontal and vertical stabilizers. This will have an impact,
and there will be a reduction in:
• Mass
• Drag
• Radar Cross Section (RCS)
The extent of these impact could only be properly assessed in
the future, and it will probably not be fully exploited until the
next generation of combat aircraft, but mass reductions of
15%-20% of the total aircraft are conceivable
If you want to believe TVC do not increase STOL and supermaneuvrability, you are welcome
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Engineer
Major
None of this contradict what I have said: "They are referring to variable exhaust nozzle. More specifically, a variation where the area of exit can be adjusted independently of throat area."
Their innovation is unique on their . Their claim is not a general statement which applies to all TVN, and is only applicable on their product.
You are obviously confused because of their marketing gimmicks. A TVN that cannot adjust the throat and exit areas independently does not have this advantage. A nozzle which can adjust the two areas independent but have no TVC capability has this advantage. Thus, this advantage is not a result of TVC.
Again, TVC is the ability to give the thrust an angular component. It cannot violate the Laws of Physics and enhance thrust out of no where.
J-20 does not use EJ200, thus whatever ITP said about the advantages of using their product is completely irrelevant in this discussion.
Reduction in IR signature is brought by the use a flat nozzle, and is not a benefit of using a TVN. As an example, F-117 and B-2 both use flat nozzles to reduce IR signature, but neither aircraft employs TVN. In any case, the talk of IR reduction is also completely irrelevant since a 3D TVN isn't going to be flat to begin with.
The increase in supercruise performance is brought on by the innovations that allow throat and exit areas to vary independently in a nozzle, and is not a result of using a TVN. A nozzle that achieve the samething without TVC capability can still bring about the said supercruise performance enhancement.
As far as lower RCS is concerned, there is no concrete proof showing F-22's style nozzle decreases RCS. In anycase, this is also irrelevant in the context of a discussion related to 3D TVN.
As usual, you cannot argue with points and are now resorting to . Pointing out disadvantages of using TVN and flaws in your claims do not equate to me claiming TVC does not enable STOL and super-manuverability.
Yes, TVN provides control when the aerodynamic surfaces are stalled, but this does not mean there is no disadvantage. In summary:
- Benefits claimed by ITP are not applicable to all TVN.
- Benefits of a flat nozzle has nothing to do with TVN.
- J-20 is not going to remove its vertical fins even if the aircraft were to fit with TVN, thus benefits of tailless aircraft in stealth and drag are irrelevant.
There is no reason why J-20 must incorporate TVN before 2018. If you are not satisfied with this, you can write to Chengdu and offer them a piece of your mind and tell them why you would be a better designer than them.
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I might just add that technology itself is not just something that can be put in a package. Only products gets put in packages.
Actually guys this discussion came up, because the J-20 does not have TVN, Migs point is to be a true new gen fighter according to Dr. Song's outstanding paper, "which by the way seige has just finished translating, TVN is part of the plan. If you don't believe me head over to the thread, "translation of amatuer chinese military article" where seige has just finished posting this translation. In section 2, paragraph 3, Dr. Song states "post stall manuevers require the aircraft to have good controllability and STABILITY". Before anyone else on here refers to another poster as a spammer or a troll, READ DR SONGS PAPER. The J-20 is an aerodynamic masterpiece, thats why any serious discussion of the J-20, in a "forum", involves aerodynamics, Mig's take on this echoes many of Dr. Songs own statements, and Mig can "do the math". Dr. Song makes the point that the J-20 would have to be aerodynamically superior to recover from a High Alpha Condition, "if the TVN fails". Now if Dr. Song is concerned about it failing, he probably assumed it would be on there. This is a thread about a fifth generation fighter aircraft in "developement". Like Mig said this is a forum where "men" come together and "talk business", as for me, I am a private pilot, a wannabbe, but I love the hardware, Mig loves the hardware, and I'm sure player loves the hardware, all of you guys love the hardware, if you're a J-20 fanboy, bless your heart. The only body I know who can definitively talk about the J-20 is Dr Song, and the tallman, maybe someone can ask them to join our forum. Now, I'm going back to "enjoy Dr. Songs honest well written Paper", thank you again seige for translating it, and it was worth the wait, I was so excited I came over here to tell the guys, really guys read Dr. Songs paper, you'll be glad you did. He talked about what a challenge it was to meet all these expectations and if your proud of the J-20, I'm just so happy that you guys have a cool airplane that you can be proud of, cause I love em all. BRAT OUT
The point of the Su-35 is that it would provide an interim solution to the Indian Rafales that are coming up in a few years. The J-11Bs and J-10Bs are either not wholly ready or wholly capable of engaging the Rafales; the J-10B has inferior aerodynamics and is equipped with PESA, and the J-11Bs are supposedly inferior to the J-10Bs.
The main issue, though, is that if the Su-35s are used against the Indians, the Russians always maintain the opportunity to turn off the power at any time with a kill switch. The Chinese would then have to negate the kill switch.
With regard to AESA and engine technology copying; for AESA, the Chinese should be further along due to their telecommunications industry allowing them to have better foundries. What nm were the Irbis-E modules built on? There is indigenous AESA research for the Chinese, and I would expect them to be more proficient than the Russians, barring Russian design advantages.
For engine technology, the main limit to the Chinese engines is metallurgy and manufacturing, not the engine design. Even though the Chinese successfully obtained a copy of the CFM-56 for reverse-engineering, they were unable to produce a military variant in time to power the J-10As. The Chinese have their own TVC research, by the way.
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With regards to the J-20 needing this kind of research, barring the AESA, the J-20 is perfectly fine without TVC systems. The J-20 project is built around the weaknesses of Chinese engine technologies. It opts for its chosen design because in the event that it cannot obtain the needed engine power due to failures in the WS-15 program, it will still have the aerodynamics needed to succeed. It would be a far better fighter if it had TVC equipped, but it would remain a perfectly adequate air-superiority fighter against 4.5th generation fighters.
The main issue, though, is that if the Su-35s are used against the Indians, the Russians always maintain the opportunity to turn off the power at any time with a kill switch. The Chinese would then have to negate the kill switch.
With regard to AESA and engine technology copying; for AESA, the Chinese should be further along due to their telecommunications industry allowing them to have better foundries. What nm were the Irbis-E modules built on? There is indigenous AESA research for the Chinese, and I would expect them to be more proficient than the Russians, barring Russian design advantages.
For engine technology, the main limit to the Chinese engines is metallurgy and manufacturing, not the engine design. Even though the Chinese successfully obtained a copy of the CFM-56 for reverse-engineering, they were unable to produce a military variant in time to power the J-10As. The Chinese have their own TVC research, by the way.
===
With regards to the J-20 needing this kind of research, barring the AESA, the J-20 is perfectly fine without TVC systems. The J-20 project is built around the weaknesses of Chinese engine technologies. It opts for its chosen design because in the event that it cannot obtain the needed engine power due to failures in the WS-15 program, it will still have the aerodynamics needed to succeed. It would be a far better fighter if it had TVC equipped, but it would remain a perfectly adequate air-superiority fighter against 4.5th generation fighters.
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