Shenyang / Chengdu 6th Gen Demonstrators?

Trijets had some history. Some of it was overwater. But there was also United's "Denver rule": the ability to reach either coast out of Denver on a hot day. East was just a long way and a heavy take-off, West was minimum safe altitude over the Rockies if you lost an engine.
As for this thing... could be a lot of reasons.
de Havilland too?
 
I wouldn't bet on it being a tech demonstrator. J-10 and J-20 were both prototypes reasonably close to production configuration.


That statement really is not aging well...
Well is it more of a YF-22 or first EMD flight of F-22 in 1997? it looks like the latter to me just by the radome alone. Just as with the J-20/J-35 there will be many tweaks and mods they will do to it as testing and maturation happens before they settle on a final design
 
What were the arguments/reasons for trijets?
Smaller Shorter routes over water, plus hot and high performance.



There are lots of interesting design choices on this aircraft...

View attachment 753717
Dual mains and nose like the Su34, so I suspect it's more of a striker than an air-to-air monster (Su27/F-15 analogue).


wing area 95 m2
volume 75 m3
volume of weapon bay 16.3 m3 (20%)
3 RD-33 x 9500 kgf = 28500 kgf
maximum take-off weight 45 tons

the most likely role is a front-line bomber, an analogue of the Su-34
Agreed.


Could the top intake be for the middle engine? A more advanced engine might still be in development and the third engine will only be used for the demonstrator? I don't think this is likely as it would require a redesign of the internal structures and would likely negate whatever data that was gathered in the test program.

This thing should be nicknamed Mothra.
Yes, it's pretty clear that there's 3 engines on that beast.



I think we can agree on cruiser; I am just not seeing why air targets would justify such a long ranged design. That would be a lot of effort to kills some E-2s, or alternatively pick a fight with tankers near Guam. Why would range be necessary over Japanese or Philippine islands, let alone Taiwan?
I would not want to go anywhere near Guam in a plane with all the defenses there.

I suspect that some of the capabilities are loitering VLO over Japan or the PI.


That was a very non-useful design, the bomb tended to get carried along in the wake of the plane, for an unpredictable distance. While that can be addressed with guided bombs these days, it's very clear that the plane has 3 engines.
 
The 3 engines deal is really puzzling, is it because two engines are not powerful enough? Why is the nose so thick, is it a side by side cockpit like the su-34? Are those glass pieces windows? Or sensors??
It's easier to add an engine than get more thrust (reliably) developing a new engine. New engines always have teething problems. So if they are just looking for more thrust on a short timeline, it's relatively easy to produce three engines that are mature than tie yourself to new engine production if it isn't ready.
Might have started with a twin and said, that won't cut it and we don't want to wait until engine-X is ready. Let's keep the bays for 1 & 3 sized to fit engine-X if it's ready, and in the meantime, let's start producing it with three of these engines we're comfortable with.
That's my guess anyway.
 
It's easier to add an engine than get more thrust (reliably) developing a new engine. New engines always have teething problems. So if they are just looking for more thrust on a short timeline, it's relatively easy to produce three engines that are mature than tie yourself to new engine production if it isn't ready.
Might have started with a twin and said, that won't cut it and we don't want to wait until engine-X is ready. Let's keep the bays for 1 & 3 sized to fit engine-X if it's ready, and in the meantime, let's start producing it with three of these engines we're comfortable with.
That's my guess anyway.
That's one hell of a redesign, though...
 
It's easier to add an engine than get more thrust (reliably) developing a new engine. New engines always have teething problems. So if they are just looking for more thrust on a short timeline, it's relatively easy to produce three engines that are mature than tie yourself to new engine production if it isn't ready.
Might have started with a twin and said, that won't cut it and we don't want to wait until engine-X is ready. Let's keep the bays for 1 & 3 sized to fit engine-X if it's ready, and in the meantime, let's start producing it with three of these engines we're comfortable with.
That's my guess anyway.
There may be other advantages. Like the ability to "distribute" air intakes along the top and bottom of the plane, thus reducing RCS for each in general.
 
This feels to me like a striker - three engines for high supercruise without afterburner, probably designed to launch a couple of/single hypersonic weapon(s) and also explains the large passive sideways-looking EO/IR sensors, perhaps indicating a maritime strike role.

Note I say striker rather than bomber - I feel that the internal space is insufficient for really long range and the PLAAF probably aren't that worried about intercontinental ranges, unlike the USAF. China has the distance advantage in that regard needing only to project power regionally - think Tu-22M Vs B-52. Plus the hypersonic missile provides ample stand-off range, it might even be an air-breathing hypersonic weapon they have in mind.

So I'm leaning towards this being a H-6 replacement trading speed and stealth for range.
 
i think this is going to be a strike fighter, its huge and maybe they want to use the middle engine for testing
 
There may be other advantages. Like the ability to "distribute" air intakes along the top and bottom of the plane, thus reducing RCS for each in general.
size of intakes does not scale relatively to RCS as long as the engine is well hidden. Having breakage in your skin will hurt surface radar waves management and contribute to larger RCS. You want all your intakes to be either all below or above depending the operating altitude so that the smooth skin surface can be shown to enemy radars.

The design points to a compromise to stealth to gain in other attributes. Aircraft design is a collection of compromises.
 
Just frantically caught up with this thread last 7 pages after getting the news from The war zone. Damn interesting, this is Christmas a day after Christmas. The chinese are not wasting a single minute, in mad rush toward a 6th generation combat plane.

Funny to see the old F-111A / F-111B duality returning : big striker & long range interceptor. Maybe McNamara wasn't completely dumb and wrong after all ? (runs for cover, seeing myself out).

A pity the F-22 production line wasn't extended through FB-22, the latter might have been very welcome to counter J-20 and those new beasts.

 
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Incredible that if we remove one engine and cut off the "neck" of the SAC J-XD planform, we can arrive at this design that Boeing thought out... 20 years ago! Convergent engineering indeed.
The Boeing 988-123 is detailed in a NASA report linked to in this thread. You will find it is designed to be a highly manoeuvrable strike aircraft designed for a joint force customer (USAF and USN).
1735293383225.png
 
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Incredible that if we remove one engine and cut off the "neck" of the SAC J-XD planform, we can arrive at this design that Boeing thought out... 20 years ago! Convergent engineering indeed.

View attachment 753832
Given how all stealth ultimately aims for hopeless diamond (while hopefully be still flying), VLO world will be probably about as diverse as world of WW1 bolt action rifles.
 
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The air intakes are mysterious too why go to F-22 style intakes when the J-20 has the F-35 intakes? I wonder also if the new aircraft features S-shaped ducts to hide the engines? I suppose only time will tell.
 
it is a bit meaning of strategic fighter
The air intakes are mysterious too why go to F-22 style intakes when the J-20 has the F-35 intakes? I wonder also if the new aircraft features S-shaped ducts to hide the engines? I suppose only time will tell.

DSI like F-35 is unproven or might be inefficient beyond M2.0.

Carret with diverter is relatively complex but provides more robust performance in higher Mach
 
Given how all stealth ultimately aims for hopeless diamond (while hopefully be still flying), VLO world will be probably about as diverse as world of WW1 bolt action rifles.
Yep. Ultimately SAMs and radars and whatnot works the same way for everyside, so the method for avoiding detection stays the same.
 
The air intakes are mysterious too why go to F-22 style intakes when the J-20 has the F-35 intakes?
With the strake / LERX above then a F-35 or J-20 style DSI intake simply wouldn't work because it diverts the boundary later in two directions but the top one of them is blocked off here, so the flow would end up being ingested by the intake. Hence a more traditional Super Hornet style double diverter Caret intake.
 
I'm interested by a few details.

The combination of 2 x Caret and 1 x DSI intake is odd - I thought immediately that the Caret intakes suggests speeds above Mach 1.8 would be in play but then the top DSI inlet makes less sense.

Despite the radically different shape it does have something of a J-20 feel about it, so I wonder if there is some elements of commonality under the skin.

My gut feeling is this is something conceptually like the Sukhoi T-60 but designed with a greater understanding of stealth, but then I can't see the need for three engines. T-60 made do with 2 AL-31F for 60,000kg class aircraft. Maybe 3 x WS-19?

Brute force supercruise? But then why not make it longer and more slender?

T-60 early version:

Gc58mPAWIAACHko.jpg
 
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With the strake / LERX above then a F-35 or J-20 style DSI intake simply wouldn't work because it diverts the boundary later in two directions but the top one of them is blocked off here, so the flow would end up being ingested by the intake. Hence a more traditional Super Hornet style double diverter Caret intake.
Maybe the DSI has a bleed area somewhere along the bump?
 
Brute force supercruise? But then why not make it longer and more slender?
But then now you run into problems at low speed being just a flying wing with no horizontal or vertical tails

On another note, I wonder why the control surfaces actuator fairings are angled completely tilted from the air flow direction. Is there a particular structural/mechanical challenge here or they double as some novel lifting devices?
 
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My gut feeling is this is something conceptually like the Sukhoi T-60 but designed with a greater understanding of stealth, but then I can't see the need for three engines. T-60 made do with 2 AL-31F for 60,000kg class aircraft. Maybe 3 x WS-19?

View attachment 753834

Some thoughts:

Third engine for endurance over the island chains/distant strike

Third engine for electrical power for Radar/ DEW/ECM/ECCM

Third engine for BLC for carrier takeoff and landing, fluidic control, or - even more out there - laminar flow?
 
But then now you run into problems at low speed being just a flying wing with no horizontal or vertical tails
That perfectly describes what SAC design is now.

I guess the problem with stretching is that the exhaust would be in a very uncomfortable position. Either the intake duct is too long or the underfuselage inlet is in some weird carved-out section ala Xmas tree fighter, and I guess SAC wasn't willing to take the leap.
 
As Chris pointed out, this seems consistent across different pictures.

I think this might be a fake canopy painted black where the cockpit is located to fool observers.
IMG_8245-1.jpeg
The aircraft might have small slits like the ones seen on the B-21.

Fully movable wingtips on the other aircraft:
Gfu6EEibkAEpou1.jpg
 
I'm away from all my files (which at that time were paper) but I seem to vaguely recall from back in the 1990s a bloke with the handle 'Agent-X' reporting a sighting of a vehicle of similar size and planform to this Chinese machine from one of the viewing points around Groom Lake.

Agent-X might even be on SPF.

Chris
 
*spills drink ...AGAIN* What ?! 3 of them? Is that was Xian was rumoured from knowledgeable folks to fly too? Mao almighty...:D
 
*spills drink ...AGAIN* What ?! 3 of them? Is that was Xian was rumoured from knowledgeable folks to fly too? Mao almighty...:D
I believe the Xi’an thing turn out to be AWACS Y-20 that flew earlier today. Since I heard the original rumour stated that XAC will fly something, just not what people expected. With how excited people for H-20 this would fit the bill
 
The designations being used are J-XDS (Shenyang) and J-36 (Chengdu).

There is a lot of speculation flying around an "insider" post saying that we've seen two of the "tea cups" from the "tea set" but not the "tea pot". Meaning like NGAD this is a family of systems and we haven't see the most important one yet.
 
Them side looking radars kinda point to air to air role

As for 6gen we haven't got any definition as to what defines 6th gen . also note that for F35 , that supercruise requirement for 5th gen went AWOL

For now its a fit funny as non existing NGAD is 6gen , but anything flying can't posibly be.
 
1735299812225.png

"There will not be a bid for (the Chinese) sixth generation fighters. Both of them have completely different designated roles while complimenting each other. CAC’s sixth generation prototype is a triple powerplant (designed for) “long range combat”, emphasizing on high stealth, large combat range, high speed and high munition carrying capacity. SAC’s sixth generation prototype is a dual powerplant (designed for) “sea-air twinning (probably has a carrier-based version?)”, emphasizing on stealth, supermaneuvrability, large combat range, high AAM carrying capacity. CAC’s prototype is around 26 meters long, (while) SAC’s prototype is around 21 meters long!
 
During the 2000s a medium size/medium range supersonic stealth fighter bomber concept (JH-XX? Project 176?) was studied by the 601 Institute. It featured a tailless swept wing design with a twin seat cockpit. A mock-up (head section?) was constructed at SAC during 2013. A recent rumor (August 2022) suggested that the JH-XX project might have progressed into the prototype manufacturing stage at SAC. The latest images suggested that another new 6th generation fighter prototype besides J-36 (see above) flew for the first time on December 22, 2024 over the sky of Shenyang. The aircraft appears more like a multirole stealth fighter (J-XX) rather than a traditional fighter bomber. It features tailless "lambda" shaped swept wings with two movable tail fins with adjustable slant angles, depending on the flight situations of the aircraft. This "adjustable tail fin" design has two main positions: the "horizontal" position allows J-XX to achieve maximum stealth and minimum drag, while the "vertical” position allows J-XX to achieve maximum maneuverability. J-XX also features two DSI engine intakes underneath the wings with an internal weapons bay in between. An EOTS is installed underneath the nose. The aircraft could be powered by two WS-15 turbofans, but it is unclear whether they have TVC nozzles or not. Compared to J-36, J-XX appears slightly smaller but is also capable of flying various air-to-air and air-to-ground missions. Currently it is unclear whether J-36 and J-XX will enter the service with PLAAF together or they will compete against each other.
Huitong on J-XDS (Shenyang)

 
If you want to validate your tailless and finless aircraft and get performance into the flight regime you might want.....

You might be waiting for new engines.....

You might cludge an existing engine as an extra to that thrust and bingo. You can fly a research tool that proves your FCS works, check it against all those models in software and even get other stuff done. All while you wait for the promised new engines......
 

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