Chengdu J-20 5th Generation Aircraft News & Discussions

[cirr]

J-20 with "new heart" took off

 

[Figaro]

@Figaro

You can insist on whatever you feel reasonable, and I will do the same, on my part. Last time, I checked. You are not an authority of anything, whom everyone must obey. So mind your own biz, plz.

Thanks for your strong and staunch moral support, hirobo2 !

And neither are you. Why don't we agree to disagree?

 

[grey boy 2]

J-20 78273

 

[Deino]

Still no news ... all I found is this !

 

[j20blackdragon]

There's nothing wrong with doing a 'nose to nozzles' measurement because the majority of the weight of the plane is from nose to nozzles.

The F-22 is actually quite small when you remove the horizontal stabilizers.

The J-20, on the other hand, has a big fuselage, increasing weight.

Furthermore, if you look at the above pictures, you also realize how small (and swept back) the J-20's wings are. Remember that lift is the elevating force which should equal or better an aircraft's weight, and less wing area lowers lift. Swept back wings (while efficient at high speeds) also lower lift at low speeds. The Concorde was notorious for taking off at high speeds and requiring extra long runways because of the sweep angle of the wings. The J-20 is supposed to have short take-off capabilities. Remember the '4S' capabilities?

You can also increase lift by increasing velocity. But for that you need powerful engines and high thrust to weight ratio, which you probably can't do with underpowered AL-31 or WS-10.

That's why the J-20 is such a conundrum.

Why is the plane so big?
Why are the wings so small and swept back?
Where is the WS-15 to power this giant plane?
I have no idea.

 

[Deino]

There's nothing wrong with doing a 'nose to nozzles' measurement because the majority of the weight of the plane is from nose to nozzles.

Point is only; if You take a wrong image - like this one above which is already so often used and dismissed as WRONG - or one showing them not in the same scale, then the whole "comparison from nose to nozzle" it's useless ...

Just look, the J-20 in that diagram is longer than the Flanker, which is WRONG:

Again, this comparison by a satellite image surely has a margin of error, but the J-20 cannot be longer than a Flanker esp. if in Your chart a standard "long-sting" Su-27 and not the short-sting Su-33 is used.

 

[j20blackdragon]

Image below overlays a Su-27 over the J-20. I assume they equalized the nozzle size. The J-20 is clearly bigger. Look at the length from nose to nozzles. Look at the thickness and girth of the fuselage.

 

[Figaro]

Image below overlays a Su-27 over the J-20. I assume they equalized the nozzle size. The J-20 is clearly bigger. Look at the length from nose to nozzles. Look at the thickness and girth of the fuselage.

These kinds of diagrams are not accurate ... the J-20 angle was clearly different than that of the Su-27 ... hence, your overlapping claim is wrong.

Point is only; if You take a wrong image - like this one above which is already so often used and dismissed as WRONG - or one showing them not in the same scale, then the whole "comparison from nose to nozzle" it's useless ...

Just look, the J-20 in that diagram is longer than the Flanker, which is WRONG:

View attachment 426686

Again, this comparison by a satellite image surely has a margin of error, but the J-20 cannot be longer than a Flanker esp. if in Your chart a standard "long-sting" Su-27 and not the short-sting Su-33 is used.

That diagram was published years ago and is known to be wrong. But yet @Asoka still insists that its right. I've also seen this picture being recirculated in the NextBigFuture website, only confirming its invalidity.

 

[Deino]

Image below overlays a Su-27 over the J-20. I assume they equalized the nozzle size. The J-20 is clearly bigger. Look at the length from nose to nozzles. Look at the thickness and girth of the fuselage.

Why is that so difficult to understand ! Don't You want to or do You prefer to ignore the fact??

You take two images of a J-20 and a Flanker, size them roughly by eyeballing to the same nozzle diameter and come to the conclusion that the J-20 is overall longer while on the other side You have a - YES I admit - blurred image of both a Flanker and a J-20 side by side and the J-20 is clearly shorter. How could it be then larger ????

That's impossible.

 

[Figaro]

Why is that so difficult to understand ! Don't You want to or do You prefer to ignore the fact??

You take two images of a J-20 and a Flanker, size them roughly by eyeballing to the same nozzle diameter and come to the conclusion that the J-20 is overall longer while on the other side You have a - YES I admit - blurred image of both a Flanker and a J-20 side by side and the J-20 is clearly shorter. How could it be then larger ????

That's impossible.

If you see someone post one image on top of another, that is a clear indication that it is inaccurate. Some posters don't seem to understand the frame of reference ...

 

[j20blackdragon]

Why is that so difficult to understand ! Don't You want to or do You prefer to ignore the fact??

You take two images of a J-20 and a Flanker, size them roughly by eyeballing to the same nozzle diameter and come to the conclusion that the J-20 is overall longer while on the other side You have a - YES I admit - blurred image of both a Flanker and a J-20 side by side and the J-20 is clearly shorter. How could it be then larger ????

That's impossible.

First, it's not my image. I found it on the internet.

Second, explain how the overlay can be wrong if the nozzle size and angle of the AL-31 have been equalized?

Third, did you not "eyeball" a small and blurry satellite photo and draw the yellow lines yourself?

Fourth, what if the Chinese Flanker is slightly larger than the Russian Flanker? Now we're thinking outside of the box.

 

[Deino]

First, it's not my image. I found it on the internet.

Second, explain how the overlay can be wrong if the nozzle size and angle of the AL-31 have been equalized?

Third, did you not "eyeball" a small and blurry satellite photo and draw the yellow lines yourself?

Come on, what a lame argument !

I admitted that image is blurred and I also admitted that there is an error included but that error is for both the same since the blur is the same. So again even a blurred image showing a smaller horse standing beside a larger elephant does not make the horse larger if You use two different images in two different positions at different angles with just being sized to the same size by guess.

Again: explain how could a smaller thing become larger only by using different images ?

Deino

 

[Figaro]

First, it's not my image. I found it on the internet.

Second, explain how the overlay can be wrong if the nozzle size and angle of the AL-31 have been equalized?

Third, did you not "eyeball" a small and blurry satellite photo and draw the yellow lines yourself?

Fourth, what if the Chinese Flanker is slightly larger than the Russian Flanker? Now we're thinking outside of the box.

Then you’re wrong. It’s just an internet image and yet you use it to prove your point. The fact is satellite imagery has indicated the J-20 is shorter in length than the flanker series by over a meter. The consensus for the J-20 is 20 to 20.3 meters. If you want to be incorrect ... the. Go ahead. I don’t k why you are so insistent on it’s lengh

Come on, what a lame argument !

I admitted that image is blurred and I also admitted that there is an error included but that error is for both the same since the blur is the same. So again even a blurred image showing a smaller horse standing beside a larger elephant does not make the horse larger if You use two different images in two different positions at different angles with just being sized to the same size by guess.

Again: explain how could a smaller thing become larger only by using different images ?

Deino

These J-20 fanbois can’t even get the length of their aircraft right

There's nothing wrong with doing a 'nose to nozzles' measurement because the majority of the weight of the plane is from nose to nozzles.

The F-22 is actually quite small when you remove the horizontal stabilizers.

The J-20, on the other hand, has a big fuselage, increasing weight.

Furthermore, if you look at the above pictures, you also realize how small (and swept back) the J-20's wings are. Remember that lift is the elevating force which should equal or better an aircraft's weight, and less wing area lowers lift. Swept back wings (while efficient at high speeds) also lower lift at low speeds. The Concorde was notorious for taking off at high speeds and requiring extra long runways because of the sweep angle of the wings. The J-20 is supposed to have short take-off capabilities. Remember the '4S' capabilities?

You can also increase lift by increasing velocity. But for that you need powerful engines and high thrust to weight ratio, which you probably can't do with underpowered AL-31 or WS-10.

That's why the J-20 is such a conundrum.

Why is the plane so big?
Why are the wings so small and swept back?
Where is the WS-15 to power this giant plane?
I have no idea.

There's nothing wrong with doing a 'nose to nozzles' measurement because the majority of the weight of the plane is from nose to nozzles.

The F-22 is actually quite small when you remove the horizontal stabilizers.

The J-20, on the other hand, has a big fuselage, increasing weight.

Furthermore, if you look at the above pictures, you also realize how small (and swept back) the J-20's wings are. Remember that lift is the elevating force which should equal or better an aircraft's weight, and less wing area lowers lift. Swept back wings (while efficient at high speeds) also lower lift at low speeds. The Concorde was notorious for taking off at high speeds and requiring extra long runways because of the sweep angle of the wings. The J-20 is supposed to have short take-off capabilities. Remember the '4S' capabilities?

You can also increase lift by increasing velocity. But for that you need powerful engines and high thrust to weight ratio, which you probably can't do with underpowered AL-31 or WS-10.

That's why the J-20 is such a conundrum.

Why is the plane so big?
Why are the wings so small and swept back?
Where is the WS-15 to power this giant plane?
I have no idea.

Your last 4 lines indicate you know nothing about the J-20 at all. I think Dave Mujumundar and Kyle Mizokami even know even more about it than you do. Seriously, go read up the facts and stop embarrassing yourself with these ignorant posts. Using terms such as “big”, “small”, and “giant” prove my point. The most surprising thing is that you have J-20 in your name. The J-20 is not a “conundrum” at all; if you even glance at the Wikipedia page, you’ll see why they designed it the way they did. Or even better, go and read up Dr. Song’s aerodynamic paper.

 

[j20blackdragon]

Explain how the overlay is wrong if the author equalized the size and angle of the nozzles. Still no answer?

 

[Figaro]

Explain how the overlay is wrong if the author equalized the size and angle of the nozzles. Still no answer?

Oh come on ... there’s something called a frame of reference for any photo. Thats why satellite imagery is much more conducive than simply aligning 2 images and assuming they were taken at the exact same angle ... which they’re not. And once again, the J-20 is not a “giant” plane. Let’s stop playing around with kids terms shall we ...