Photos and analysis of China's J-20 fighter as it nears first flight

[Steve Pace]

Since the J-20 appears to be more than 70 ft (21.3 m) long, I believe it is to be a fighter-bomber. -SP

 

[brunobardini]

Thank's a lot overscan,i'm french, "nobody's perfect".
This fist one is especially for flateric if i remember his passion "YF-23"

 

[Avimimus]

Avimimus - Mr. Aboulafia openly acknowledges the shortcomings of his "quickie" analysis and IMO was not trying to make some over arching statement befitting airpower for every country.

Also the reason his perspective might "appear" American influenced is that America has had more actual combat sorties since WWII (Korea, Vietnam, Kosovo, Gulf I & II, A-stan, etc.) then every other nation on earth combined. America has the most integrated, overwhelming tactical and strategic airpower overmatch over the past fifty years and has developed operational theory that has literally "written the airpower handbook".

Now is this some magical guarantor of future superiority, no of course not, but any airpower analysis will be heavily influenced by American thought.

I'm not surprised - it looked like a well informed approach. I didn't intend to call into question his capabilities either. It is just a bit dangerous, as on these people do try to generalize such reports to every situation and country (and one also gets very fuzzy notions like "5th generation" floating around).

I can't disagree with the logic for American influence - although I once remember a Russian article that pointed out the fact that the U.S. has (mercifully), not had to fight a war on its own soil in 150 years. So, experience may be primarily strategic and expeditionary in nature. It also explains the occasional "impracticalness" that sometimes appears.

Anyway, I also don't doubt that the United States will maintain a conventional superiority. There is a lot of global irritation over economic and political interference, but few around the world have an interest in the United States completely losing its military position (even if there are interests in it losing economic or political control). The only possibility would be if the government and democratic process were to lose their legitimacy internally (which might lead to more militarism anyway).

 

[Abraham Gubler]

The J-20 looks extremely aft loaded. The centre of lift from those wings is going to be around ¾ down the length of the aircraft! Those canards will need to be lift generating surfaces unless the forward half of the aircraft is basically empty. I think we can rule it out as any kind of a bomber if the bomb bay is located forward of the wings because dropping bombs would so significantly change the centre of gravity of the aircraft.

 

[Sundog]

The J-20 looks extremely aft loaded. The centre of lift from those wings is going to be around ¾ down the length of the aircraft! Those canards will need to be lift generating surfaces unless the forward half of the aircraft is basically empty. I think we can rule it out as any kind of a bomber if the bomb bay is located forward of the wings because dropping bombs would so significantly change the centre of gravity of the aircraft.

Most modern canard fighter designs are slightly stable to neutrally stable before the canard is added. Here's an image showing approximates, but it's difficult to assess aerodynamic centers without good plan views. But I don't see the J-20 having anymore problems with cg and dropping weapons than the F-22. Now in this image, I just guessed the angle graphically, but land based aircraft usually have the c.g. somewhere between ten to fifteen degrees in front of the main gear contact point. It seems the c.g. to ac relationship will be just fine for a slightly unstable fighter design based on what I'm seeing.

 

[Abraham Gubler]

But I don't see the J-20 having anymore problems with cg and dropping weapons than the F-22.

Well the F-22 has the CG around level with the aft 1/3 of the bomb bay. The J-20 has the bomb bay well forward of the CG (using the main gear yard stick). Also look at how far forward of CG the nose is compared to the F-22 (or F-35). Either the J-20 has far heavier engines or this nose is relatively empty. If it’s a light nose then there aren’t the processors in their to give it 5th generation level situational awareness.

 

[Firefly 2]

But I don't see the J-20 having anymore problems with cg and dropping weapons than the F-22.

Well the F-22 has the CG around level with the aft 1/3 of the bomb bay. The J-20 has the bomb bay well forward of the CG (using the main gear yard stick). Also look at how far forward of CG the nose is compared to the F-22 (or F-35). Either the J-20 has far heavier engines or this nose is relatively empty. If it’s a light nose then there aren’t the processors in their to give it 5th generation level situational awareness.

Seems logical enough. But this is just a prototype. Could this change as the aircraft is developed? The YF22 underwent numerous changed before becoming the Raptor.

 

[saintkatanalegacy]

if it's using WS-10(which is kinda short)

then there would enough room to actually place the bomb bays at the center of gravity...

if it's using the WS-15(which is the longer one)

then the bomb bays should be placed at a forward position...

(c) paralay

 

[Abraham Gubler]

Seems logical enough. But this is just a prototype. Could this change as the aircraft is developed? The YF22 underwent numerous changed before becoming the Raptor.

They didn't change the basic configuration of the aircraft. If you are going to fly a prototype without the weight of mission systems you usually fit lead bars or similar to compensate for them.

 

[donnage99]

What I find amusing is that while the inlet design of the j-20 looks alot like the wind tunnel models that have been released publicly, most pictures that dominates magazines (including chinese magazines) uses this model that has the inlets that looks like some tech from Boeing ATF bid has been successfully transfered over.

 

[rousseau]

Hmmm
I believe Chinese are eager to use ride-wave theory as concept of their Fighter indeed.
But I highly doubted they really comprehended it right
The word "blow" I used above could be accurate but on DSI it should be replaced as "press".

 

[saintkatanalegacy]

interesting...

could work for variable compression and inlet mass flow scheduling etc. though I reckon they chose the DSI configuration with maintenance, weight savings and cost in mind.

it should be able to perform like an axissymmetric inlet(half-cone with splitter plate) like on the Mirage with engine tolerance taking care of alpha and beta sensitivity while the cone is doing the necessary compression and shock. the AL-31 family is quite known to be forgiving after all...

for a fixed intake, it would a compromise among subsonic, transonic and supersonic performance and see what best suits the mission profile and requirements. you have to give them credit for making extensive experiments with DSI research though

 

[flateric]

http://www.kanwa.com/mrdt/showpl.php?id=836

my humble effort to understand GoogleTranslator output

Andrei Chang: Within weeks we will see the flight of Chinese J-20

KDR Chengdu Reuters: Chinese Defense Review today, the spokesman Andrei Chang told the media: If the weather is all normal, the world will see the J-20 flight within a few weeks. In fact countdown has already begun.

Andrei Chang re-emphasized using a J-20 engine improvements made in China. Russia has never sold 117S to China. The current range of the [advanced Russian] engine is not exported to China. T-50 uses 117 engine instead of 117S. J-20 is also not equipped with AL31F or AL31FN engine. Russian journal of shape memory engine to find the heart beat of their own understanding (?).

About 117 engines, they are also should be tested further, and are not completely finalized. Andrei Chang that the T-50 can not be fielded in 2013.

 

[saintkatanalegacy]

Russian journal of shape memory engine to find the heart beat of their own understanding (?).

hmmm... perhaps it meant that the turbine geometry is variable and automatically adjusts itself

 

[amsci99]

Russian journal of shape memory engine to find the heart beat of their own understanding (?).

hmmm... perhaps it meant that the turbine geometry is variable and automatically adjusts itself

The correct translation is merely 'Pinkov' the editor of Kanwa Defense Review asserting his former claims that it is not powered by the 117 or the AL-31 series as he knows the configuration and shapes of various Russian turbo engines better than he knows the inner workings of his heart.

 

[overscan (PaulMM)]

My "Truckology" comparison suggests J-20 is 22.29% longer than a J-10.

Given my preferred estimate of 16.42m for J-10 length, the J-20 comes out at 20.08m.

If the smaller 15.5m figure is correct, that makes the J-20 18.95m.

 

[PAK FA]

ugh this could be a sort of active way to blow boundary layer up, however, since the

I have read your explanation and i like it a day ago i read an article about DSIs however i do not understand something if the bump is fixed, the position of the sonic shock is fixed, on aircraft like the SR-71 the VG inlet moves the shock cone of the inlet to adjust as speed increases, on the MiG-29 inlet for example the shock waves are create ahead of the lower lip so no supersonic flow enters the intake, how can you create a VG DSI inlet if the inlet will make the sonic shock wave inside the intake duct?
On a mirage III the half shock cone of its inlet moves ahead and aft and basicly is similar to the bump of the DSI.

I know nozzles will change the diameter of the nozzle from convex to concave depending in the nature of the flow if it is supersonic or subsonic.
but then why raking an inlet? just change the concavity or convexity of the inlet duct and there is no need of shock cone or shock ramps, i do not understand can you elaborate?

 

[brunobardini]

INTERSTING NEWS on I TELE (CANAL PLUS +)
J-20 hunter bomber will not be operational before several years.(French experts one french TV).
Probably did they forget the number of persons on the tarmaks?
They have spys and THALES net filters and a lot of retroenginiery.
For to their space program to launch their russian rocket there were 65000 persons with russians and french engineers in the first and second shot. (and their space quest is a question of marketing and communication not space research, in "France" for launching ARIANE V, 500 people are nesessary.said experts and Jean-François Clervoy on ARTE (c'est dans l'air).
To meditate!!!!!!

But for the experts they still excavate the dustbins and are still unable of ratraper the knowledge of the SNECMA of Rolls-Royce or of ONERA.

 

[GeorgeA]

This is on the front page of the Wall Street Journal today, so the story has crossed over into the mainstream media. Will be interesting to see if the "Gates blinded by his anti-F-22 jihad" story sticks.

 

[sferrin]

This is on the front page of the Wall Street Journal today, so the story has crossed over into the mainstream media. Will be interesting to see if the "Gates blinded by his anti-F-22 jihad" story sticks.

It should. He was. Or rather, I think one of his advisors (Gordon England) fed him a bunch of biased BS and Zero took the opportunity to kill a weapon system (because that's what liberals do). Gates was merely the one who pulled the lever on the guillotine.

 

[Yamachoma]

Hi All!

I registered in hope to find Nazi UFO stories before Christmas then I saw this thread, People in UK are also interested in our J20?

an video of some sort of test is also attached

http://www.youtube.com/watch?v=LlkUCNlxA2w&feature=player_embedded

 

[saintkatanalegacy]

ugh this could be a sort of active way to blow boundary layer up, however, since the

I have read your explanation and i like it a day ago i read an article about DSIs however i do not understand something if the bump is fixed, the position of the sonic shock is fixed, on aircraft like the SR-71 the VG inlet moves the shock cone of the inlet to adjust as speed increases, on the MiG-29 inlet for example the shock waves are create ahead of the lower lip so no supersonic flow enters the intake, how can you create a VG DSI inlet if the inlet will make the sonic shock wave inside the intake duct?
On a mirage III the half shock cone of its inlet moves ahead and aft and basicly is similar to the bump of the DSI.

I know nozzles will change the diameter of the nozzle from convex to concave depending in the nature of the flow if it is supersonic or subsonic.
but then why raking an inlet? just change the concavity or convexity of the inlet duct and there is no need of shock cone or shock ramps, i do not understand can you elaborate?

the supersonic shock doesn't have to be inside the duct per se

the pores in the bump are placed ahead of the duct and generates shock

moving the bump forward and backward in a curved duct adjusts compression by decreasing and increasing the duct's cross section

though I think doing that would require insane engineering... since you're manipulating a bump that would also require manipulating the duct's already curved geometry which means the surface should be somehow elastic... which is why I reckon the intake is fixed

 

[PAK FA]

the supersonic shock doesn't have to be inside the duct per se

the pores in the bump are placed ahead of the duct and generates shock

moving the bump forward and backward in a curved duct adjusts compression by decreasing and increasing the duct's cross section

though I think doing that would require insane engineering... since you're manipulating a bump that would also require manipulating the duct's already curved geometry which means the surface should be somehow elastic... which is why I reckon the intake is fixed

I understand that but then you loose all the advantages of the fixed bump, simplicity and not moving parts and the bump is not as stealthy as a flat surface as the one seen on the F-22 chines

 

[Matej]

Hi All!

I registered in hope to find Nazi UFO stories before Christmas then I saw this thread, People in UK are also interested in our J20?

an video of some sort of test is also attached

Welcome here. Thanks for the video, its the high speed taxi test. But I will disappoint you - you will never find here that kind of fiction stupidity like the Nazi UFO stories, this forum is dedicated to the real aerospace projects.

 

[Deino]

Some suggest a first flight tomorrow 6. January !!

Deino

 

[paperforce]

I also came across this today in doing some research on 3d models for a steam punk game.
http://www.creativecrash.com/marketplace/3d-models/aircraft/military/fighter/c/-3d-model-china-chengdu-j-20-fighter-jet
some great 3d models of the j-20

 

[Steve Pace]

It must be a heavy airplane, or it's on a short runway, since it has two 'chutes. -SP

 

[Matej]

One rumour is that they were almost unable to do the high speed taxi tests with the early J-10 with the front gear leg in air because the insufficient length of the runway in Chengdu. So it can have the influence.

 

[Foxglove]

Deino, the caption under the second photo you last uploaded reads: J-20 landing. Now correct me if I'm wrong, but if logic doesn't fail me, landing means a given object has been airborne?

 

[Yamachoma]

if it's using WS-10(which is kinda short)

then there would enough room to actually place the bomb bays at the center of gravity...

if it's using the WS-15(which is the longer one)

then the bomb bays should be placed at a forward position...

(c) paralay

The Room is reserverd for WS-15， see the other one: 2002,

It was just officially explained on CCTV

Public Codename for J20 in China : Silk Ribbon/Black Silk Ribbon,

Also, according very early posts and current posts back to 2008 from both public researchers and some offical news, the J20 has the following Characteristics.

Inlet: Adjustable DSI
Flight Control: Optical, Differencial All movable tail to enhance post stall manuevers
Airframe : Co Plane Lifting Body（Vortex from angled canard is utilized), Short Coupled Canard, Adjustable Strake？
Stealth: Plasma on some sections, New Material to subdue sourceless detections.

PLAAF Normal General Naming Stadard:

J : Fighter
L: Trainer
Q: Ground Attack
H : Heavy Bomber/Refuel/Heavy Support
JH: Fighter Bomber
Z: Helicopter
Y: Transporter/AWAC/Electronic/Observation
E: Other Electronic/AWAC

FB: Export
Su/IL/Tu : Russian Imported Planes

Rumoured Cockpit 1

Rumoured Cockpit 2 for 2002 【2002 is Backopening】， not for f35

NOTE: IT HAS BEEN FOUND BY USERS HERE THAT THIS ONE IT IS ACTUALLY A F35 JSF FIGHTER COCKPIT
WITHE THE LINK [http://www.youtube.com/watch?v=sHJMIOlHt1U]

Rumoured Prototype Cockpit 3 trainer

 

[Yamachoma]

Hi All!

I registered in hope to find Nazi UFO stories before Christmas then I saw this thread, People in UK are also interested in our J20?

an video of some sort of test is also attached

Welcome here. Thanks for the video, its the high speed taxi test. But I will disappoint you - you will never find here that kind of fiction stupidity like the Nazi UFO stories, this forum is dedicated to the real aerospace projects.

I should correct the term: Nazi built Saucer Like Flying Objects near the end of the WWII

 

[Matej]

Thats much better.

 

[Orionblamblam]

Deino, the caption under the second photo you last uploaded reads: J-20 landing. Now correct me if I'm wrong, but if logic doesn't fail me, landing means a given object has been airborne?

If the plane is *landing,* that means it was still airborne when it popped the drogue chutes. That seems a tad unwise. Might be a high-speed taxi test that got as far as rotation, then popped drogues.

 

[flateric]

Rumoured Cockpit 2 for 2002 【2002 is Backopening】， not for f35

before posting BS, check it twice (said I to myself)
gosh, they almost copied everything...but this is definitely not a flying vehicle - note, for example, lack of canopy lock units

 

[Steve Pace]

Isn't January 6 in China? -SP

 

[Deino]

Some strange obeservations on the pictures from today ... !

With the picture on the bottom I thought to be sure that's the AL-31FN ... but now ... looks very strange and much like the WS-10A.

Otherwise I can't think that they already have both prototypes finished.

Let's wait and see ....

 

[Foxglove]

A handful of pics I found on the paralay site, don't think I've seen them here before. In the second picture the shape of the headrests suggests they've adapted the J-10 ejection seat for the J-20.
Deino, the exhausts do look different(colour, texture). There are two options here: these are pics of two different aircraft and 2001 and 2002 have been fitted with different engines( the bort number in the top pic is illegible) or 2001 has already had two pairs of engines test-fitted.

 

[LowObservable]

Deino

The exhaust differences are mystifying. Wait and see is probably the best choice right now.

 

[Colonial-Marine]

Back before they were revealed I wasn't expecting either 5th gen fighter the Russians or Chinese were supposedly working on to make the F-22A look like a small aircraft.

 

[fduch]

Rumoured Cockpit 2 for 2002 【2002 is Backopening】， not for f35

http://www.youtube.com/watch?v=sHJMIOlHt1U&feature=player_embedded