Chengdu J-20 5th Generation Aircraft News & Discussions

[dingyibvs]

Yes, an aircraft is very complex, so how much of the very complex MiG 1.44 do you about, and how much of the even more complex J20 do you know about? How can you say one is derived from the other if all you have are some exterior pictures?

 

[Deino]

Guys ... To admit I'm a bit surprised and even annoyed to see what was discussed since my two-weeks holydays in France.

I still wonder why there is so much hate between the two sides? On the one side there are the Fan- Boys who Take it as a personell attack if you say the J-20 is Not the best, if there might me some external input in its development and most of all if you only assume that it is using AL-31FNs Even if all evidence say so and nothing hints to a WS-10.
On the other side there are the nay-sayers, who rate the J-20 a plain stupid copy or a Development of another failed design ...

Stupid, indeed.....both sides since ignoring facts or even accepting certain possibilities since they don't fit the own point of view, will prevent to see the real Story behind.

By the Way...any latest News or especially Images of the LRIP birds.

Deino

PS ... just found Even if i am Not sure if they are new!

 

[Pepsi Cola]

This tells me that you have no experience in R/D and manufacturing, and probably watch too many bad movies.

Am going to give you a clue: There is no such thing as a 'blueprint' in aviation.

You want to see a 'blueprint' ? Go look at the bicycle.

People toss the word 'blueprint' around as if they know what they are talking about. An aircraft is a million times more complex than a bicycle. It is not possible to have a single printout of an aircraft that give details to the many subsystems necessary to make that aircraft flyable.

Have you mistaken? A blueprint doesn't have to fit on one paper. And it really doesn't matter how many papers it is. That's not part of my point, my point is that unless the J20 engineers obtained official Russian document regarding the MIG 1.44 a, there's no way you can say that J20 used the MIG as reference.

 

[gambit]

Yes, an aircraft is very complex, so how much of the very complex MiG 1.44 do you about, and how much of the even more complex J20 do you know about? How can you say one is derived from the other if all you have are some exterior pictures?

EACH winged aircraft can trace its lineage back the Wright Flyer. That is no exaggeration. Go back one more step and you will touch the bird, of whom the Wright Brothers studied how birds flexes their wings to maneuver in flight.

Aerodynamics is the study of flow around shapes. So if you are an aerodynamicist, you would have a pretty good guess of an airframe based upon its shapes, from body to wings. It also mean that if you see two SIMILAR shapes, meaning not IDENTICAL, from the same knowledge, you would also have a pretty good guess as to their performance. You cannot in good professional conscience argue that the behaviors of a canard-ed aircraft is the same as a conventionally tailed aircraft. All of this came from observation.

Since the canard is ahead of the wing, shaping and positioning the canard is even more crucial than for a conventional tailplane assembly. Do it inefficiently and you will negative affect lift over the main wing. Do it wrong and your design will crash.

So when you see this...

It unlikely that you, as an aerodynamicist, will guess that the J-20 came from the older J-9. The shaping of the J-20's canards are too similar to the MIG's. The canards' dihedral (upsweep angle) exists on the MIG and J-20, but not on the J-9. Why do you think there is a canard dihedral on one design but not the other ? What about the quantity of flight control surfaces ? Which has more and why ?

When I transferred from the F-111 to the F-16, I do not need to know the aerodynamics of the F-16 to know that its flight characteristics will be different from the F-111. And I was correct based upon appearance alone. YOU would, not merely could, make the same correct guess.

In rotary winged aircrafts, aka 'helicopter', just from noting the number of blades in the main rotor assembly, one can guess the performance of that helo to a high degree of accuracy. The more the number of blades, the more stable the flight but the less maneuverability. Which explains why the Cobra have only two blades because as an attack aircraft, it needs maneuverability to make quick aspect changes to deal with threats to self and to ground forces. On the other hand, the Apache, while also designed as an attack helo, it was also designed to carry more ordnance and other non-weapons related systems for other combat roles, hence four blades.

The point here is that while there are limits to appearances, noting similarities and differences can tell us much, even to origin of design.

 

[Deino]

Finally back to Topic ... This is surely new.

 

[Pepsi Cola]

Oka

EACH winged aircraft can trace its lineage back the Wright Flyer. That is no exaggeration. Go back one more step and you will touch the bird, of whom the Wright Brothers studied how birds flexes their wings to maneuver in flight.

Aerodynamics is the study of flow around shapes. So if you are an aerodynamicist, you would have a pretty good guess of an airframe based upon its shapes, from body to wings. It also mean that if you see two SIMILAR shapes, meaning not IDENTICAL, from the same knowledge, you would also have a pretty good guess as to their performance. You cannot in good professional conscience argue that the behaviors of a canard-ed aircraft is the same as a conventionally tailed aircraft. All of this came from observation.

Since the canard is ahead of the wing, shaping and positioning the canard is even more crucial than for a conventional tailplane assembly. Do it inefficiently and you will negative affect lift over the main wing. Do it wrong and your design will crash.

So when you see this...

It unlikely that you, as an aerodynamicist, will guess that the J-20 came from the older J-9. The shaping of the J-20's canards are too similar to the MIG's. The canards' dihedral (upsweep angle) exists on the MIG and J-20, but not on the J-9. Why do you think there is a canard dihedral on one design but not the other ? What about the quantity of flight control surfaces ? Which has more and why ?

When I transferred from the F-111 to the F-16, I do not need to know the aerodynamics of the F-16 to know that its flight characteristics will be different from the F-111. And I was correct based upon appearance alone. YOU would, not merely could, make the same correct guess.

In rotary winged aircrafts, aka 'helicopter', just from noting the number of blades in the main rotor assembly, one can guess the performance of that helo to a high degree of accuracy. The more the number of blades, the more stable the flight but the less maneuverability. Which explains why the Cobra have only two blades because as an attack aircraft, it needs maneuverability to make quick aspect changes to deal with threats to self and to ground forces. On the other hand, the Apache, while also designed as an attack helo, it was also designed to carry more ordnance and other non-weapons related systems for other combat roles, hence four blades.

The point here is that while there are limits to appearances, noting similarities and differences can tell us much, even to origin of design.

Okay? So how is your comment relate to my previous one? Your bullshit skill is through the roof buddy.

So what if Chinese engineers look at some photos of MIG 1.44 or whatever other aircrafts, and say oh hey they are doing something different with their canards, Why don't we test it on a model and see how it works? If it's good we put it on our aircraft, if it doesn't suit our aircraft, we'll opt out for something else. And by the way MIG 1.44 isn't the first fighter that has the canards in that fashion, Saab Gripen and Dassault Rafale both come before the MIG and both have the same style of canards.

So what if the new Rolls Royce Trent 1000, and General Electric GEnx both have the same looking chevrons on them? Do you say they use each other as reference? Of course not. RR can look at GE's newest engine all they want and be like, hey those chevrons are interesting, I don't know what they do but why don't I carve a model and test it in a wind tunnel and see how it performs? That's not using it as reference, that's using it as inspiration, because to use the GE as reference, RR has to obtain a data or a design sheet from GE and follow them exactly. And any common sense would tell you that designing your fighter aircraft using another fighter's photographs as reference is the dumbest thing you can do.

Drop your argument already, it sucks.

 

[gambit]

So what if Chinese engineers look at some photos of MIG 1.44 or whatever other aircrafts, and say oh hey they are doing something different with their canards, Why don't we test it on a model and see how it works? If it's good we put it on our aircraft, if it doesn't suit our aircraft, we'll opt out for something else.

Then we can say that the J-20 did came from the MIG 1.44 project. And there is nothing bullshit about it.

And by the way MIG 1.44 isn't the first fighter that has the canards in that fashion, Saab Gripen and Dassault Rafale both come before the MIG and both have the same style of canards.

Yeah...So did the Wright Flyer.

So what if the new Rolls Royce Trent 1000, and General Electric GEnx both have the same looking chevrons on them? Do you say they use each other as reference?

No idea what the hell you are talking about.

 

[Pepsi Cola]

Then we can say that the J-20 did came from the MIG 1.44 project. And there is nothing bullshit about it.


Yeah...So did the Wright Flyer.

How can you say that? Are you the J20 engineer? And to say the J20 "came from" MIG 1.44 is the most ignorant thing. What do you mean came from? Don't give me that vague term.

You've been evading the word "reference" ever since I pointed out your error in my statement earlier. Opting out for something weak and vague like "came from", and still talk like you got your shit sorted.

My point is that MIG 1.44 could be J-20's inspiration, and there's no way it's a reference. That's my point, and that's all I'm here to debate about. Not fucking aerodynamics.

And by the way, I'd have let your Wright Flyer comment slide if you quoted a better section of my comment, but you're really bad at quoting, so I have to point out that the quote talked about the canards. Wright Flyer did not have canards. So no, you can't include the Wright Flyer.

 

[gambit]

And by the way, I'd have let your Wright Flyer comment slide if you quoted a better section of my comment, but you're really bad at quoting, so I have to point out that the quote talked about the canards. Wright Flyer did not have canards. So no, you can't include the Wright Flyer.

You should really take time and do basic research. This American invention called 'The Internet' is a wonder...

https://en.wikipedia.org/wiki/Wright_Flyer

The Flyer was a canard biplane configuration.

 

[Pepsi Cola]

I get it buddy, it's okay. Here you go for your "reference"

And sorry mods, I know it's a bit off topic, but I have to point it out for this smart ***.

You should really take time and do basic research. This American invention called 'The Internet' is a wonder...

https://en.wikipedia.org/wiki/Wright_Flyer

Okay? Maybe I'm wrong. It did have canards, but definitely not the same type as canards on those fighters. Am I right? Sorry I don't know what the **** is the "Internet", I'm so dumb.

 

[gambit]

I get it buddy, it's okay. Here you go for your "reference"
And sorry mods, I know it's a bit off topic, but I have to point it out for this smart ***.

Ah...Those things are called 'scallops' or 'serrations' and they have NOTHING to do with the jet engine : Aeroacoustics.

What you see is the engine pod, or housing, and those features can be installed on any jet engine from any manufacturer. They have no performance effects on the engine itself. They are there to help reduce noise. Without them, the jet engine would perform the same.

For what you tried to dispute me...

So what if the new Rolls Royce Trent 1000, and General Electric GEnx both have the same looking chevrons on them? Do you say they use each other as reference?

Source: https://defence.pk/threads/chengdu-...tes-discussions.111471/page-388#ixzz4G0bwQ2v0

This is what a jet engine look like.

If GE want to copy, or reference, or inspired by RR, they would definitely need an RR engine. Not the pod/housing.

YOU ARE WRONG. Simple as that.

When it comes to aerodynamics, the outside matter because the outside is what comes into physical contact with air molecules. So if the Chinese engineers used the MIG 1.44 as inspiration, might as well call it a reference.

Okay? Maybe I'm wrong. It did have canards, but definitely not the same type as canards on those fighters. Am I right?

Then using your own argument, since the MIG 1.44's and the J-20's canards do not look like the canards on the J-9, but more alike to each other, we can say that the J-20 was 'inspired' or 'referenced' from the MIG.

Sorry I don't know what the **** is the "Internet", I'm so dumb.

Compare to me, yes you are. You want to play rough ? So can I. I tried to be polite to you, but if you want to rude about a technical debate, I will accommodate you.

 

[Deino]

Guys ... Simply stop This stupid copy-paste discussion. If you like to continue start an own thread on how much a certain design might me influenced by another one .... but no longer here.

End of debate.

Deino

 

[gambit]

Guys ... Simply stop This stupid copy-paste discussion. If you like to continue start an own thread on how much a certain design might me influenced by another one .... but no longer here.

End of debate.

Deino

As far as I am concerned, the matter is TECHNICALLY relevant and related. But you and the PDF Chinese can relax because the Chinese mod, in the interest of protecting his fellow Chinese, are going to delete my posts anyway.

 

[Pepsi Cola]

Ah...Those things are called 'scallops' or 'serrations' and they have NOTHING to do with the jet engine : Aeroacoustics.

What you see is the engine pod, or housing, and those features can be installed on any jet engine from any manufacturer. They have no performance effects on the engine itself. They are there to help reduce noise. Without them, the jet engine would perform the same.

For what you tried to dispute me...


This is what a jet engine look like.

If GE want to copy, or reference, or inspired by RR, they would definitely need an RR engine. Not the pod/housing.

YOU ARE WRONG. Simple as that.

When it comes to aerodynamics, the outside matter because the outside is what comes into physical contact with air molecules. So if the Chinese engineers used the MIG 1.44 as inspiration, might as well call it a reference.


Then using your own argument, since the MIG 1.44's and the J-20's canards do not look like the canards on the J-9, but more alike to each other, we can say that the J-20 was 'inspired' or 'referenced' from the MIG.


Compare to me, yes you are. You want to play rough ? So can I. I tried to be polite to you, but if you want to rude about a technical debate, I will accommodate you.

Sorry that I AM WRONG. (BOLD AND CAPITAL LETTERS FOR SPECIAL EFFECTS) Did i say it affects how the engine perform? Gosh you need to really learn how to stay on topic. I'm fascinated by your word plays. Really, I am. The Chevrons (And yes they are called "chevron design " according to NASA and the "scallop" is simply the shape of the design ) Everything about the engine, including the noise it produced is regarded as "performance", part of the engine's marketing point, and is on the engines official spec sheet.

Seriously your latter argument is so bad that I'm honestly at loss of words. I'll let other readers decide who is right or wrong.

 

[gambit]

Sorry that I AM WRONG. (BOLD AND CAPITAL LETTERS FOR SPECIAL EFFECTS) Did i say it affects how the engine perform? Gosh you need to really learn how to stay on topic. I'm fascinated by your word plays. Really, I am. The Chevrons (And yes they are called "chevron design " according to NASA and the "scallop" is simply the shape of the design ) Everything about the engine, including the noise it produced is regarded as "performance", part of the engine's marketing point, and is on the engines official spec sheet.

Seriously your latter argument is so bad that I'm honestly at loss of words. I'll let other readers decide who is right or wrong.

In aerodynamics, shaping is visible and its effects are immediate and equally visible. So when I argued that the J-20's shape is inspired or referenced by the MIG 1.44, there are technical legitimacy to that argument.

When you tried to refute that argument by using a feature that have no real effects whatsoever on the object, what else can you be but -- WRONG ? When we talk of engine 'performance' we mean core burn efficiency, thrust, fuel consumption rate, all the things that helps an engine move an aircraft. Noise is not a part of that. All airliners have been flying for decades without that aeroacoustics features. Jet engine technology have been progressing without that feature.

So no, GE cannot use the external features of the engine pod/housing on an RR engine as reference or inspiration, but Chengdu certainly can use the external features of the MIG 1.44 to design the J-20.