Chengdu J-20 5th Generation Aircraft News & Discussions

[Asoka]

I am afraid bro you don't know what is afterburner bro it is on a wet or dry thrust can show me clip that fighter jet flying without hot butts its normal engine running not afterburner is applied every 4th can do vertical climbing without use of afterburner including your J series of jets its nothing new


I already state you in my above post its not for engine but relaxed static stability of the fighter jets, first fighter jet shows a capability to super cruise was the British lightning of 60 with relatively weaker engine

1.) "show me clip that fighter jet flying without hot butts"

Here is you go, J-20 is doing a sustained vertical climbing, without a glowing red butt or red hot flame shooting of its nozzle, which a strong indicator whether the Afterburner is ON or not.

I have posted it on this page already.
https://defence.pk/pdf/threads/chen...news-discussions.111471/page-504#post-9090880

The vertical climbing started around 1:00.

2.) "its normal engine running, not afterburner is applied"

Not true. Watch this video of F-22.

You can see the afterburner is being turned ON and OFF at 18:12.

The Afterburn is ON, indicated by the red hot butt.

Moments later, the Afterburner is turned Off, no more red hot butt. Clearly, the engine is still running normally.

3.) "every 4th, can do vertical climbing, without use of afterburner, including your J series of jets. its nothing new."

That's news to me. I am astounded by my ignorance. Show me some videos, and then we could discuss them.

4.) "F-22, F-35, and F-16 have tail cropped delta wing platform, which inherently stable at supersonic state, but because of TVC engine on F-22 and F-35, they have extreme maneuverability, agility. Whereas, J-20 [is] inherently unstable, at supersonic and trans-sonic flight regime. At subsonic J-20 shows slightly positive static stability."

I think you are saying:

All you need is being unstable or have TVC, at supersonic state, to have superior supersonic maneuverability.

And because F-22 and F-35 is stable at supersonic state, but they have TVC, and that TVC, alone, give them the extreme maneuverability, agility, at supersonic state.

And since "J-20 inherently unstable, at supersonic and trans-sonic flight regime", this unstability, alone, will give J-20 the superior supersonic maneuverability, as claimed by the pilot.

Is this what you are saying?

 

[Asoka]

The F119 was listed as over 156KN in the afterburner, but some people speculate the actual figure is around 175KN.

The J-20 is a larger and heavier aircraft than the F-22, so it needs to use a jet engine with higher thrust than the F119. Otherwise, it will still be considered underpowered, not enough to meet the benchmark. And if its pilots have implied that the J-20 is outstanding in the supercruise capability, then the chance with the WS-15 could be quite likely.

Watch the Vertical climb at 25:00.

This video showing F-22 doing a slow vertical climb, w/o Afterburner at 25:00. It makes me agreed that its maximum trust, is near 175kN, rather than 160kN.

175kN x 2 = 350kN, is the total Thrust. And if Dry Thrust is 60% of that, we have 210kN. F-22's empty weight is listed as 19.7 tons. That means F-22's fuel is only around one to two tons, at the end of this video.

This is not too unreasonable, as it's demonstrating on the airport, and already near the end of its demo.

J-20 is 3.5m longer than F-22, so it is larger and heavier. I think it is reasonable that J-20's empty weight is around 22 tons. And J-20 took off from a different airport to demo at the airshow, and it disappeared from view. It is reasonable to assume, it has returned to its base. So it is reasonable to assume, it has more than 2 tons of fuel left.

I have assumed earlier that F-22 can't do a vertical climb, w/o AB, because it's maximum thrust is only listed as 160kN, while its empty weight is 19.7 tons.

"The F119 was listed as over 156KN in the afterburner, but some people speculate the actual figure is around 175KN."

This video clearly shows it CAN. So I don't think it's 160kN. It's more like, at least, 175kN as some people have speculated.

 

[gambit]

1.) "show me clip that fighter jet flying without hot butts"

Here is you go, J-20 is doing a sustained vertical climbing, without a glowing red butt or red hot flame shooting of its nozzle, which a strong indicator whether the Afterburner is ON or not.

That video DID NOT showed any sustained vertical flight.

When a pilot command a pitch change, forward momentum will impart some assistance to that change. Increase throttle will add to the perception that the aircraft is flying and gaining altitude. The time period of 1:07 to 1:12 is too short to serve as definitive proof that the J-20 can sustain a vertical flight using only engine thrust.

 

[SQ8]

That video DID NOT showed any sustained vertical flight.

When a pilot command a pitch change, forward momentum will impart some assistance to that change. Increase throttle will add to the perception that the aircraft is flying and gaining altitude. The time period of 1:07 to 1:12 is too short to serve as definitive proof that the J-20 can sustain a vertical flight using only engine thrust.

Two seals fighting over a grape. None of the AB on or AB off has anything to with either altitude or pitch but simple airspeed and energy. If the J-20 built up enough energy in its run in, it can keep basic mil thrust and actually accelerate for a while before forces acting on it take its toll.

 

[gambit]

People,

Read this and remember...

There are three types of programs in an airshow: high, medium, and flat.

http://wfpl.org/expect-a-lower-faster-thunder-air-show-thanks-to-clouds/

“For any air show, they have a high show, a low show, or a flat show, depending on the cloud ceiling,” Boyd says.

Saturday’s ceiling is not looking high, but that doesn’t mean the show will be less entertaining.

“With a flat show you actually get a little bit closer to the aircraft,” she says. “They’re gonna be flying through the venue a little bit lower, so it’ll be lower and faster.”

A 'high show' is when there is virtually clear sky which allows the flying demo to its maximum, including any vertical maneuver.

But even so, there is NO practical way for a ground observer to conclude definitively that a high performance combat jet fighter entered a vertical climb, sustain the same velocity, and even gain velocity. Forward momentum and throttle to afterburner will give the impression that such a maneuver is being executed, but in reality, if a jet is capable, by the time the jet is fully in that vertical flight like a rocket, it would be out of human sight.

So how did we come to the conclusion that the F-15 can perform such a maneuver ?

Radar confirmation of pilot testimony.

So until there is independent radar confirmation of the J-20 going vertical like a rocket, any Internet comment to that alleged capability is pure speculation.

 

[Asoka]

Two seals fighting over a grape. None of the AB on or AB off has anything to with either altitude or pitch but simple airspeed and energy. If the J-20 built up enough energy in its run in, it can keep basic mil thrust and actually accelerate for a while before forces acting on it take its toll.

Not true, if are climbing vertically, in a sustained climb, more than a few seconds.

If you turn your plane, vertically, like in a Cobra Manouvre, the plane's body and wings, acts as a giant air brake, quickly bleeds off your horizontally momentum. Your airspeed quickly drops to near 0, without gaining any height.

Watch the Cobra maneuver in this video.

If you want to climb with the help of momentum, you climb at the most optimum angle your wings allows, without stalling. You don't want to climb VERTICALLY, if you to use the built up momentum.

When you are VERTICAL, your wings do not contribute, to any upward lifting force, your whole lift comes from the engine's thrust.

If your engine's thrust is > than the plane's weight, you keep climb up, vertically. If not, you fall back down like a leaf.

At vertical, your plane behaves more like a rocket, not like an airplane.

 

[Ultima Thule]

1.) "show me clip that fighter jet flying without hot butts"

Here is you go, J-20 is doing a sustained vertical climbing, without a glowing red butt or red hot flame shooting of its nozzle, which a strong indicator whether the Afterburner is ON or not.

I have posted it on this page already.
https://defence.pk/pdf/threads/chen...news-discussions.111471/page-504#post-9090880

The vertical climbing started around 1:00.

2.) "its normal engine running, not afterburner is applied"

Not true. Watch this video of F-22.

You can see the afterburner is being turned ON and OFF at 18:12.

View attachment 415583

The Afterburn is ON, indicated by the red hot butt.

View attachment 415582

Moments later, the Afterburner is turned Off, no more red hot butt. Clearly, the engine is still running normally.

3.) "every 4th, can do vertical climbing, without use of afterburner, including your J series of jets. its nothing new."

That's news to me. I am astounded by my ignorance. Show me some videos, and then we could discuss them.

4.) "F-22, F-35, and F-16 have tail cropped delta wing platform, which inherently stable at supersonic state, but because of TVC engine on F-22 and F-35, they have extreme maneuverability, agility. Whereas, J-20 [is] inherently unstable, at supersonic and trans-sonic flight regime. At subsonic J-20 shows slightly positive static stability."

I think you are saying:

All you need is being unstable or have TVC, at supersonic state, to have superior supersonic maneuverability.

And because F-22 and F-35 is stable at supersonic state, but they have TVC, and that TVC, alone, give them the extreme maneuverability, agility, at supersonic state.

And since "J-20 inherently unstable, at supersonic and trans-sonic flight regime", this unstability, alone, will give J-20 the superior supersonic maneuverability, as claimed by the pilot.

Is this what you are saying?

This is your prove i am sorry to say you have no basic knowledge about fighter jets and their engines in this cilp not even single shot interior of J-20 engine so I can assure you if in this clip its definitely shows hot butts
I can show lots of clip J-20 with hot butts but no afterburner is applied
Its relaxed static stability energy maneuverbilty theory from lockheed martin fighter mafia group" before the 4 the gen jets pilot trying to maneuver the jet but jets trying remains same attitude because of central of gravity that is positive static stability, F-16 is the first jet that show negative static stability which means that its fuselage remains uncontrolled because of central of gravity and pilot trying to level flight mechanical flight control system is useless for relaxed static stability jets that why they were developed fly by wire tech specially for relaxed static stability jets and please Google yourself relaxed static stability and energy maneuverability theory bro

 

[Asoka]

This is your prove i am sorry to say you have no basic knowledge about fighter jets and their engines in this cilp not even single shot interior of J-20 engine so I can assure you if in this clip its definitely shows hot butts
I can show lots of clip J-20 with hot butts but no afterburner is applied
Its relaxed static stability energy maneuverbilty theory from lockheed martin fighter mafia group" before the 4 the gen jets pilot trying to maneuver the jet but jets trying remains same attitude because of central of gravity that is positive static stability, F-16 is the first jet that show negative static stability which means that its fuselage remains uncontrolled because of central of gravity and pilot trying to level flight mechanical flight control system is useless for relaxed static stability jets that why they were developed fly by wire tech specially for relaxed static stability jets and please Google yourself relaxed static stability and energy maneuverability theory bro

Bro, I am trying to ask you a question, to confirm what I think of your post. And you write back with this rambling, confused nonsense. I have read about relaxed stability in third generation jets, because of improved digital flight control. Thank you.

I was asking:

I think you are saying:

All you need is being unstable or have TVC, at supersonic state, to have superior supersonic maneuverability.

And because F-22 and F-35 is stable at supersonic state, but they have TVC, and that TVC, alone, give them the extreme maneuverability, agility, at supersonic state.

And since "J-20 inherently unstable, at supersonic and trans-sonic flight regime", this unstability, alone, will give J-20 the superior supersonic maneuverability, as claimed by the pilot.

Is this what you are saying?

Please answer my question, first.

 

[Ultima Thule]

Not true, if are climbing vertically, in a sustained climb, more than a few seconds.

If you turn your plane, vertically, like in a Cobra Manouvre, the plane's body and wings, acts as a giant air brake, quickly bleeds off your horizontally momentum. Your airspeed quickly drops to near 0, without gaining any height.

Watch the Cobra maneuver in this video.

If you want to climb with the help of momentum, if you climb at the most optimum angle your wings allows, without stalling, not VERTICALLY.

When you are VERTICAL, your wings do not contribute, to any upward lifting force, your whole lift comes from the engine's thrust.

If your engine's thrust is > than the plane's weight, you keep climb up, vertically. If not, you fall back down like a leaf.

At vertical, your plane behaves more like a rocket, not like an airplane.

Their 2 T/W ratio engine and jets which one is you talking about, T/W ratios above 1 is not a new thing which excess thrust available for jets compared to their weight eg f-16 , f-14 ,f-15, su series of jets mig-29 all have thrust to weight ratios is above 1

Bro, I am trying to ask you a question, to confirm what I think of your post. And you write back with this rambling, confused nonsense. I have read about relaxed stability in third generation jets, because of improved digital flight control. Thank you.

I was asking:

I think you are saying:

All you need is being unstable or have TVC, at supersonic state, to have superior supersonic maneuverability.

And because F-22 and F-35 is stable at supersonic state, but they have TVC, and that TVC, alone, give them the extreme maneuverability, agility, at supersonic state.

And since "J-20 inherently unstable, at supersonic and trans-sonic flight regime", this unstability, alone, will give J-20 the superior supersonic maneuverability, as claimed by the pilot.

Is this what you are saying?

Please answer my question, first.

Yes bro you're right on that part because Delta canard wing shows extreme agility and maneuverability without use of TVC engines, like tail cropped Delta wing jet like f-22, f-35 required TVC to achieve similar agility and maneuverability with Delta canard platform doing without using TVC engine

 

[Asoka]

Their 2 T/W ratio engine and jets which one is you talking about, T/W ratios above 1 is not a new thing which excess thrust available for jets compared to their weight eg f-16 , f-14 ,f-15, su series of jets mig-29 all have thrust to weight ratios is above 1

I was always talking about the TWR of the whole plane, itself, not just the engine.

"T/W ratios above 1 is not a new thing which excess thrust available for jets compared to their weight eg f-16 , f-14 ,f-15, su series of jets mig-29 all have thrust to weight ratios is above 1"


I know the TWR > 1 started with F-15, in the 70's, and most 3rd generations fighter jets have TWR > 1. This is I totally agreed. I have never stated, or implied, otherwise.

Notice, that's the Maximum Thrust or Wet Thrust (not military thrust or dry thrust) that is greater their body weight.

But it is the 4th or 5th generation jet of F-22, J-20 and T-50, (with their TWR > 10 engines, such as F119, WS-15, 117S) that the Dry thrust begins to exceed their body weight.

This is new for 4th or 5th generation jet. This is why I have seen F-22 and J-20 (probably T-50 also) could climb vertically with their Dry Thrust, alone.

Many 3rd generations jet could climb, vertically, with their Afterburners. This I have no doubt. I have seen many videos. Nothing special about it.

I am not contending only J-20 could climb vertically, with or w/o afterburner. I just seen F-22 could do that too.

That makes me believe the Maximum Thrust of F119 engine, is higher than listed 160kN, and closer to 175kN, as some people have speculated.

I am only contending that J-20 could do a vertical climb w/o AB, with the intended WS-15 engines, not the WS-10 or AL-31-FN-M1 engine, which has Max thrust around 125-145kN.

And since the J-20 could do a vertical climb w/o AB, I have calculated that would take at least a dry thrust of 126kN or maximum thrust of 210kN, based on my an estimated empty weight and fuel load of (22 tons and 4 tons). Of course, I could be wrong on this. I don't know the exact empty weight, and its fuel load, during the demo. Only the pilots know.

"Yes, bro you're right on that part because Delta canard wing shows extreme agility and maneuverability without use of TVC engines, like tail cropped Delta wing jet like f-22, f-35 required TVC to achieve similar agility and maneuverability with Delta canard platform doing without using TVC engine."

Yes, Bro. I agreed. The movable "Delta canard wing" of J-10, Rafael, Typhoon, and J-20 are extremely unstable. Until, the designers have mastered Digital Fly-by-wire Flight Control systems in the 1990's, with fast flight computers and supercomputer modeling.

US designers have experimented with movable "Delta canard wing" on F-16 and F-15, in the 1980's. The flight control software and hardware wasn't ready to handle the extreme instability.

So they gave up.

That's why you don't see it on F-22. They make it up with TVC, and a powerful engine, and advanced frame design, that incorporated vortex generation, superbly.

However, the relaxed stability of "Delta canard wing" design is only one of the key ingredient for J-20, to achieve superior supersonic maneuverability.

Otherwise, J-10, Rafael, and Typhoon, could also claim this flight quality. But I have never heard anyone of their pilots claimed this.

They only claimed superior subsonic maneuverability, which are true.

Why is that?

Because superior supersonic maneuverability, requires several more factors, other than relaxed stability at supersonic state.

 

[juj06750]

↑
plz ban this guy
keep discussing irrelevant things in thread

 

[Ultima Thule]

I was always talking about the TWR of the whole plane, itself, not just the engine.

"T/W ratios above 1 is not a new thing which excess thrust available for jets compared to their weight eg f-16 , f-14 ,f-15, su series of jets mig-29 all have thrust to weight ratios is above 1"


I know the TWR > 1 started with F-15, in the 70's, and most 3rd generations fighter jets have TWR > 1. This is I totally agreed. I have never stated, or implied, otherwise.

Notice, that's the Maximum Thrust or Wet Thrust (not military thrust or dry thrust) that is greater their body weight.

But it is the 4th or 5th generation jet of F-22, J-20 and T-50, (with their TWR > 10 engines, such as F119, WS-15, 117S) that the Dry thrust begins to exceed their body weight.

This is new for 4th or 5th generation jet. This is why I have seen F-22 and J-20 (probably T-50 also) could climb vertically with their Dry Thrust, alone.

Many 3rd generations jet could climb, vertically, with their Afterburners. This I have no doubt. I have seen many videos. Nothing special about it.

I am not contending only J-20 could climb vertically, with or w/o afterburner. I just seen F-22 could do that too.

That makes me believe the Maximum Thrust of F119 engine, is higher than listed 160kN, and closer to 175kN, as some people have speculated.

I am only contending that J-20 could do a vertical climb w/o AB, with the intended WS-15 engines, not the WS-10 or AL-31-FN-M1 engine, which has Max thrust around 125-145kN.

And since the J-20 could do a vertical climb w/o AB, I have calculated that would take at least a dry thrust of 126kN or maximum thrust of 210kN, based on my an estimated empty weight and fuel load of (22 tons and 4 tons). Of course, I could be wrong on this. I don't know the exact empty weight, and its fuel load, during the demo. Only the pilots know.

"Yes, bro you're right on that part because Delta canard wing shows extreme agility and maneuverability without use of TVC engines, like tail cropped Delta wing jet like f-22, f-35 required TVC to achieve similar agility and maneuverability with Delta canard platform doing without using TVC engine."

Yes, Bro. I agreed. The movable "Delta canard wing" of J-10, Rafael, Typhoon, and J-20 are extremely unstable. Until, the designers have mastered Digital Fly-by-wire Flight Control systems in the 1990's, with fast flight computers and supercomputer modeling.

US designers have experimented with movable "Delta canard wing" on F-16 and F-15, in the 1980's. The flight control software and hardware wasn't ready to handle the extreme instability.

So they gave up.

That's why you don't see it on F-22. They make it up with TVC, and a powerful engine, and advanced frame design, that incorporated vortex generation, superbly.

However, the relaxed stability of "Delta canard wing" design is only one of the key ingredient for J-20, to achieve superior supersonic maneuverability.

Otherwise, J-10, Rafael, and Typhoon, could also claim this flight quality. But I have never heard anyone of their pilots claimed this.

They only claimed superior subsonic maneuverability, which are true.

Why is that?

Because superior supersonic maneuverability, requires several more factors, other than relaxed stability at supersonic state.

You will not trying to understand and insisting your crap opinions you have no logic you lives in wrong assumptions and wishful thinking, rafale, ef-2000, grippen, and j-10 all have great maneuverability and agility at supersonic and trans- sonic flight regime because of Delta canard design

 

[Asoka]

You will not trying to understand and insisting your crap opinions you have no logic you lives in wrong assumptions and wishful thinking, rafale, ef-2000, grippen, and j-10 all have great maneuverability and agility at supersonic and trans- sonic flight regime because of Delta canard design

"You will not trying to understand and insisting your crap opinions you have no logic you lives in wrong assumptions and wishful thinking"

I guess you are running out of good things to say, and is just ranting your frustrations. I can't help you with that.

"rafale, ef-2000, grippen, and j-10 all have great maneuverability and agility at supersonic trans- sonic flight regime"

Back up your assertions with some proof about their Supersonic maneuverability. Give me some quotes or reports from the pilots or test pilots. I don't need proof for subsonic maneuverability. I know its true.

No one want to stay at the high drag, transonic region. Talk about maneuverability at trans-sonic flight regime, is crazy.

If you think relaxed stability, with delta canard wings, at supersonic state, will give you superior maneuverability and agility, comparable to that of F-22, at that supersonic region.

You are wrong.

It takes a lot more than that.

 

[Ultima Thule]

"rafale, ef-2000, grippen, and j-10 all have great maneuverability and agility at supersonic trans- sonic flight regime"

Back up your assertions with some proof about their Supersonic maneuverability. Give me some quotes or reports from the pilots or test pilots. I don't need proof for subsonic maneuverability. I know its true.

No one want to stay at the high drag, transonic region. Talk about maneuverability at trans-sonic flight regime, is crazy.

If you think relaxed stability, with delta canard wings, at supersonic state, will give you superior maneuverability at that region. You are wrong.

It takes more than that.

You first prove that J-20 is using WS-15 from day one, you first prove that WS-15 has thrust of 210 KN and WS-15 has a TVC nozzles, they lighter because of composite materials their engines relatively powerful compare to their weight they have TWR above 1 its world fact about those jets not my personal opinon, your j-20 has extremely maneuverable and agile with Delta canard design those European is not maneuverable and agile with a same layout what a bogus logic you have you ..... (edited by moderator)

 

[Asoka]

You first prove that J-20 is using WS-15 from day one, you first prove that WS-15 has thrust of 210 KN and WS-15 has a TVC nozzles, they lighter because of composite materials their engines relatively powerful compare to their weight they have TWR above 1 its world fact about those jets not my personal opinon, your j-20 has extremely maneuverable and agile with Delta canard design those European is not maneuverable and agile with a same layout what a bogus logic you have you sh!t head, you have brain of 8 year old kid you insane

"You first prove that . . . "

I already listed my reasons or proofs for my assertions in my numerous previous posts.

"Your j-20 has extremely maneuverable and agile, with Delta canard design. Those European is not maneuverable and agile, with a same layout. What a bogus logic, you have. You sh!t head. You have brain of 8 year old kid. You insane"

I am fine, thank you. I am not insane.

Looks like you don't have any proofs that "rafale, ef-2000, grippen, and j-10 all have great maneuverability and agility at supersonic trans- sonic flight regime". and just want to vent your frustration.

I said it takes a lot more than "Delta canard design" for superior supersonic maneuverability, comparable to that of F-22. That's why I don't believe J-10, Rafael and Typhoon has that.

I believe the current J-20 has superior supersonic maneuverability, comparable to that of F-22, because,

1.) it has the agile, differentially moving, "Delta canard design", PLUS,

2.) two powerful WS-15 engine, that has at least 210kN of thrust each, PLUS,

3.) a huge internal fuel storage of 12 tons, to support long Supersonic Cruise, PLUS,

4.) 3-D differential turning TVC nozzles, PLUS,

5.) all moving, differentially activated, tails, PLUS,

6.) a long slender body for superior supersonic state, PLUS,

7.) internal weapon storage for minimize drag, PLUS,

8.) adjustable DSI air intake, that could be optimized for subsonic, as well as supersonic speed.

If that doesn't do it for J-20. I don't know what will.