Shenyang / Chengdu "6th Gen" Aircraft - News and Analysis

[FighterJock]

My thoughts too Sferrin, with the two main weapon bays you can forget about a centre line hardpoint for external ordinance/fuel tanks.

 

[Sferrin]

My thoughts too Sferrin, with the two main weapon bays you can forget about a centre line hardpoint for external ordinance/fuel tanks.

You could always do it like the F-105 and have the centerline pylon be ON the weapons bay door.

 

[Scott Kenny]

New look at the underside of the J-XDS/SAC 6th gen (although some detail has been lost due to AI enhancement!).

Via ACuriousPLAFan/SDF:

View attachment 814305

View attachment 814306

Those inlets look really weird from that angle. Doesn't look right for a DSI, doesn't have the spacing needed for a caret, ...

Really wish they'd gotten a picture with the underside of the aircraft more exposed to the sun. Just a slightly bigger bank angle is all I'm asking!

So we'd be able to see any contours on the underside of the nose.

Two bays... but I do wonder - centreline external hardpoint?

Combined response:

Wouldn't it create clearance issues for the stores in the bays?

It may, but picture a buddy-fueling tank on the centerline. So your side bays are likely filled with fuel tanks anyways.

Plus they may stick on an asymetric camera pod for weapons release testing.

 

[Deino]

Interesting observation on the SAC J-XDS prototype(s) via Syrida2887/SDF:

"Some changes have been noticed: the silver part of the joint between the tail nozzle and the fuselage disappeared, which should be the result of some measures to optimize the thermal infrared signal? (And the length of the convergent deflection plate of 2D TVC seems to longer.)!

According to some people, the new prototype may have changed the engine from the vector version of WS-10 to the vector version of WS-15."

I know that KI-enhancements, whether intentional or automatically aren't really helpful & often obscure more details than they clarify, but this could indeed point to either a 2. prototype or an engine change: the silver ring (aka WS-10C) vs now an all-black nozzle (aka WS-15).

I know it's no proof at all, but it could be an explanation and especially the clearly longer and larger nozzles are another hint towards an engine change!

 

[donnage99]

OR.... it's just AI screwing up the details

 

[Deino]

OR.... it's just AI screwing up the details

Or it is an 100% AI ?? ... I think we nowadays have to keep this option in mind whenever we see something new.

However, would an automatic AI-enhancement result in such larger longer nozzles even if not intentionally manipulated?

AI is currently holding us hostage—in more ways than one!

 

[Avimimus]

With regard to a hypothetical centre-line hardpoint, I do honestly suspect that you may all be right to discount it.

Nevertheless, I still want to think it through some more:
- The centre-line trough is rounded so that it could probably fit a missile of the right diametre in a semi-conformal hardpoint.
- The side-bays are far enough apart that they might be able to open around the missile (considering that its maximum diametre would be achieved very close to where the bay door begins.
- Given that the weapon in question would likely be a large stand-off weapon it might also be expected to be fired prior to the use of internally mounted weapons.
- It would allow carrying a single outsized weapon, making it possible for the design to augment the J-36 mission profile if necessary (in spite of its presumably shorter main bays).

So these are the reasons why I've hesitated to discount it entirely.

It might be interesting to try to estimate the diametre of that trough between the weapon bays. That said, the possibility can likely be discarded due to the placement of the antennas behind the trough (which, when taking into account the landing gear strut, doesn't add that much length - although I suppose it would still add diametre and perhaps the antennas are a bit higher up rearward facing ones that could allow a cold dropped missile to be close to them without too much trouble).

 

[Avimimus]

However, would an automatic AI-enhancement result in such larger longer nozzles even if not intentionally manipulated?

Yes, we can trust nothing.

That said, the J-36 prototypes have been testing multiple nozzle configurations - so it lends a degree of plausibility that the J-XDS prototypes might as well. Does this suggest a second J-XDS prototype I wonder? There was that photo apparently showing it flying alongside two CCAs, so the flight testing process might be further along than we think (or at least the PLAAF wants us to think it is further along).

 

[Schwerter_105]

With regard to a hypothetical centre-line hardpoint, I do honestly suspect that you may all be right to discount it.

imo the idea makes sense to some degree, but the specific geometry of that trough (or at least from what we can currently see from post 2997) doesn't really lend itself all that well to conformal storage, as it seems a bit too wide and shallow. If we're talking about something with a non-circular cross-section (say something akin to JSM/LRASM/Kh59MK2/AKF98, something with a rounded rectangular or trapezoidal cross-section) then it may well be suited for the trough geometry but for round munitions not so much I think.

But again since we're talking about 6th gen jets here which probably should have relatively good stealth even with such external stores, assuming that the munitions itself will be designed to fit the jet and have stealth design features itself is certainly not out of the question. I remember reading about a number of US design teams study stealth munitions with conformal storage in the 70s or 80s (Northrop and maybe boeing?). If nothing else, I'd certainly be interested to see what would ultimately come of such a design path.

 

[snne]

Really wish they'd gotten a picture with the underside of the aircraft more exposed to the sun. Just a slightly bigger bank angle is all I'm asking!

 

[Scott Kenny]

Thank you but I specifically wanted the light at the angle in that photograph I had quoted to check for any odd shadows on the side of the nose.

Like how we saw a pretty pronounced hook on the wing shape of the B-21s with a bright leading edge, a shadow, and then a bright "belly" to the wing.

 

[donnage99]

Or it is an 100% AI ?? ... I think we nowadays have to keep this option in mind whenever we see something new.

However, would an automatic AI-enhancement result in such larger longer nozzles even if not intentionally manipulated?

AI is currently holding us hostage—in more ways than one!

I would say the lack of edge alignment is suspect.

 

[Waterb-Doge]

Those inlets look really weird from that angle. Doesn't look right for a DSI, doesn't have the spacing needed for a caret, ...

Really wish they'd gotten a picture with the underside of the aircraft more exposed to the sun. Just a slightly bigger bank angle is all I'm asking!

So we'd be able to see any contours on the underside of the nose.

I got these on X last year, might help.

 

[Scott Kenny]

I got these on X last year, might help.

Thank you!

 

[SUPER=BUG]

I personally feel that the 2024 versions of the J36 and J-XD both use the WS-10C engine, and then at some point in 2025 they switched to the latest WS-15 engine. I think Deino's analysis makes a lot of sense. Of course, we can't rule out that the J-XD, considering future aircraft carrier environments, might have a WS-15 that looks different because of some extra anti-corrosion treatment.

 

[SUPER=BUG]

Has a photo from this angle been posted? Of course, it's an old photo.

 

[djfawcett]

Not sure how I missed this earlier:

3x 30-35klb engines would give the J-36 a TWR of about 1.27:1 at 50% fuel. (~105klb MTOW, ~82,500lbs at combat maneuvering weight. ~55k empty, 25k fuel, 2500lbs AAMs)

An F-16C-50/52 is looking at a TWR of about 1.18 in the same situation of 50% fuel and 4x AMRAAM+2x AIM9

The F-22 has a TWR of about 1.25 with 50% fuel and 6x AMRAAMs+2x AIM9

I don't think the J-36 is going to have any trouble at all regaining energy after a turn in a dogfight.

Sorry for the late reply. I just saw this post.

This analysis is flawed. You must be assuming the dog fighting is going to be at sea level. The available thrust is directly related to altitude and free stream velocity. Hence, all of your thrust to weight ratios are incorrect. Moreover, the drag loses are far greater on a large delta (J-36) than on a 16c or 22. The 36 may recover, but what is the delta T during recovery. I suspect the 22 will waste it in a turning fight if it does not blow its tail off BVR.

 

[Scott Kenny]

Sorry for the late reply. I just saw this post.

This analysis is flawed. You must be assuming the dog fighting is going to be at sea level. The available thrust is directly related to altitude and free stream velocity. Hence, all of your thrust to weight ratios are incorrect. Moreover, the drag loses are far greater on a large delta (J-36) than on a 16c or 22. The 36 may recover, but what is the delta T during recovery. I suspect the 22 will waste it in a turning fight if it does not blow its tail off BVR.

If I had access to thrust-at-altitude charts or tables I'd have used those.

As is, I've been assuming roughly-equal bypass ratios between the different engines so that their thrust fall-off with altitude is roughly equal.

 

[Manuducati]

I suspect the 22 will waste it in a turning fight if it does not blow its tail off BVR.

Never gonna happen. The J-36 is tail-less.
(Sorry, I couldn't resist )

 

[Avimimus]

Sorry for the late reply. I just saw this post.

This analysis is flawed. You must be assuming the dog fighting is going to be at sea level. The available thrust is directly related to altitude and free stream velocity. Hence, all of your thrust to weight ratios are incorrect. Moreover, the drag loses are far greater on a large delta (J-36) than on a 16c or 22. The 36 may recover, but what is the delta T during recovery. I suspect the 22 will waste it in a turning fight if it does not blow its tail off BVR.

I'd wonder, in that case, what the T/W ratios should be (also noting that there is huge uncertainty regarding the denominator here).

Also, I think it is worth noting that WVR in this era would likely involve a single turn, followed by acceleration to get the best launch conditions for a missile. So sustained turn rate for gun fight isn't likely going to be a factor.

Anyway, my main interest is in the supersonic L/D ratio and speed retention/recovery at relatively low angles of attack. The potential performance of the J-36 in BVR (particularly kinetic defense)... is a much more interesting question.

 

[Alfa_Particle]

I suspect the 22 will waste it in a turning fight if it does not blow its tail off BVR.

I suspect you’re worrying about the wrong tailless aircraft here if we’re talking WVR or just kinematics in general.

 

[Nicolas10]

This looks mean!

 

[donnage99]

I suspect you’re worrying about the wrong tailless aircraft here if we’re talking WVR or just kinematics in general.

let's not go down the unhinged debate of 6th gen somehow outmaneuver a conventional tail design of 4th or 5th gen given all things equal entering the visual range (ruling out energy, electronic, and geometric advantages).

the f-35's DAS basically usher in the new era of dogfight that no longer requires turn and burn. 2 platforms with DAS like capability will most likely ensure mutual destructions.

6th gen (rightfully) gives up on the traditional dogfighting maneuverability in the same way 4th gen gave up pure top speed of previous gen.

 

[Ainen]

the f-35's DAS basically usher in the new era of dogfight that no longer requires turn and burn. 2 platforms with DAS like capability will most likely ensure mutual destructions.

F-35 doesn't even carry a heatseeker inside, and it's close in weapon is its gun.
I.e. no, it's turn or burn.

6th gen (rightfully) gives up on the traditional dogfighting maneuverability in the same way 4th gen gave up pure top speed of previous gen.

It would be rather amusing should F-47 end up maneuverable, and will beat digested food out of designs, born at the dawn of fbw.

Earliest 4th gen designs were as fast or faster than their 3rd-gen predecessors. The gradual loss of max speed started later, and to this day didn't become a definitive trend. Rather, it settled down for different compromises.

 

[donnage99]

F-35 doesn't even carry a heatseeker inside, and it's close in weapon is its gun.
I.e. no, it's turn or burn.

huh? why would DAS like system need a heat seeking type of missile to work? and we're talking 6th gen aircraft in the context of DAS similar or superior equivalence. Why would the f-35's internal weapon carriage be relevant?

 

[Ainen]

huh? why would DAS like system need a heat seeking type of missile to work?

Well, the irrelevance of WVR - even if true, as there are multiple caveats - is applicable only to specialized WVR weapons.
For offbore ARH weapon shots, for starters, you really want to feed a 3rd coordinate(which DAS does not provide), and overall, their close-in performance is comparatively limited.
Which is why WVR weapons still exist.

and we're talking 6th gen aircraft in the context of DAS similar or superior equivalence. Why would the f-35's internal weapon carriage be relevant?

If the argument is completely broken in it's very first example ("F-35's DAS usher in a new era of dogfight that no longer requires turn and burn") - applying the wrong lesson further won't make it right.
For example, if F-35 gets off-bore DAS AMRAAM shot at F-47, but the latter's RCS alone prevents seeker lock, engagement doesn't seem to be off to a good start.

 

[tico]

The configuration of the F-47 clearly prioritizes maneuverability. The J-50 should also boast solid agility, but it seems to have ditched the side weapon bays. WVR dogfights are likely the job for these two drones. These UAVs carry a lot of weight in this setup， unlike smaller CCAs, they were most likely co-developed with the J-36 and J-50 as a unified system from day one.

 

[donnage99]

Well, the irrelevance of WVR - even if true, as there are multiple caveats - is applicable only to specialized WVR weapons.
For offbore ARH weapon shots, for starters, you really want to feed a 3rd coordinate(which DAS does not provide), and overall, their close-in performance is comparatively limited.
Which is why WVR weapons still exist.

If the argument is completely broken in it's very first example ("F-35's DAS usher in a new era of dogfight that no longer requires turn and burn") - applying the wrong lesson further won't make it right.
For example, if F-35 gets off-bore DAS AMRAAM shot at F-47, but the latter's RCS alone prevents seeker lock, engagement doesn't seem to be off to a good start.

why do you assume that the missile can only engage with a seeker lock from the missile's own radar?

 

[Alfa_Particle]

let's not go down the unhinged debate of 6th gen somehow outmaneuver a conventional tail design of 4th or 5th gen given all things equal entering the visual range (ruling out energy, electronic, and geometric advantages).

You're kidding, right? Tailless fighters can absolutely be as (if not even more) maneuverable than traditional tailed designs. This was already demonstrated by the X-36 and ICE. Your premise doesn't make sense in the way that 6th gens will inherently utilise much more advantageous aerodynamic geometries.

But let's look at the "J-50" as an example. Tailless, massive LERX-integrated nose, lambda wings with AMWs and 8 other individually controllable trailing edge control surfaces (not to mention leading edge slats), thrust vectoring, and who knows what else (active flow control?). In terms of relaxed stability it's already head and shoulders above conventional designs. There's absolutely no reason that it wouldn't be as maneuverable as conventional fighters.

6th gen (rightfully) gives up on the traditional dogfighting maneuverability in the same way 4th gen gave up pure top speed of previous gen.

You're misunderstanding this. One of the core capabilities that 6th gens are pursuing are even more robust sustained turn rates at high speed and high altitudes compared to 5th gens in order to secure the best firing position for BVR engagements. This ironically encourages very low wing loading/highly blended wing-body designs, which ultimately yields to exceptional lift coefficients. Add the inherent ultra-relaxed stability nature of tailless designs, and voila. A "natural" dogfighter with an exceptional instantaneous turn rate and kinematic profile.

 

[Ainen]

why do you assume that the missile can only engage with a seeker lock from the missile's own radar?

I think that's the case for all modern aa weapons; the only exception I can think of is starstreak/martlet, but those are only for helicopters, and in any case they're super directional...

P.s. my understanding is that verticals problem is not so much maneuverability(it affects certain maneuvers, but there are workarounds), but rather stability, especially supersonic.

 

[donnage99]

You're kidding, right? Tailless fighters can absolutely be as (if not even more) maneuverable than traditional tailed designs. This was already demonstrated by the X-36 and ICE. Your premise doesn't make sense in the way that 6th gens will inherently utilise much more advantageous aerodynamic geometries.

did the x-36 and ICE demonstrate maneuverability superior to that of traditional tail design? (the aspect of maneuverability strictly relevant to close in dogfight)

But let's look at the "J-50" as an example. Tailless, massive LERX-integrated nose, lambda wings with AMWs and 8 other individually controllable trailing edge control surfaces (not to mention leading edge slats), thrust vectoring, and who knows what else (active flow control?). In terms of relaxed stability it's already head and shoulders above conventional designs. There's absolutely no reason that it wouldn't be as maneuverable as conventional fighters.

Any actual research paper to demonstrate that these features yield a platform superior in maneuverability to traditional wing tail platform or these features are there to provide fighter like performance for a tailless fighter at supersonic speed?

You're misunderstanding this. One of the core capabilities that 6th gens are pursuing are even more robust sustained turn rates at high speed and high altitudes compared to 5th gens in order to secure the best firing position for BVR engagements. This ironically encourages very low wing loading/highly blended wing-body designs, which ultimately yields to exceptional lift coefficients. Add the inherent ultra-relaxed stability nature of tailless designs, and voila. A "natural" dogfighter with an exceptional instantaneous turn rate and kinematic profile.

you're misunderstanding this. I specifically refers to WVR engagement which requires characteristics within the encompassing term maneuverability, though overlapping with BVR engagement type of maneuvers, are also distinctly different. I even specifically set the condition as eliminating geometric, energy advantages that a platform such as 6th gen fighter, being stealthier, with better sensors, higher altitude as well as better kinetic performances at high altitude, and better supersonic performance would yield right at the merge.

 

[donnage99]

I think that's the case for all modern aa weapons; the only exception I can think of is starstreak/martlet, but those are only for helicopters, and in any case they're super directional...

P.s. my understanding is that verticals problem is not so much maneuverability(it affects certain maneuvers, but there are workarounds), but rather stability, especially supersonic.

you don't think future platform can cue a missile with a 360 degree tracking/targeting system the entire engagement envelope while maintaining positional and energy advantage?

 

[Ainen]

you don't think future platform can cue a missile with a 360 degree tracking/targeting system the entire engagement envelope while maintaining positional and energy advantage?

It is the opposite to the direction they move in, and it's in any cas is beyond the event horizon.

On currently known platforms, it's likely possible on su-57/j-36/b-21, but to my knowledge, it wasn't even considered; why? Onboard guidance and autopilot is all round superior.

In the end, F-35 example is telling; it's often used as example, yet it's in fact a very maneuverable 9g jet, which is built for anything but for exploiting high offbore WVR missile combat.
And if there's any such aircraft remaining in modern world, it's the rafale... which isn't particularly new, and is unique, rather than representative of the general trend.

 

[donnage99]

It is the opposite to the direction they move in, and it's in any cas is beyond the event horizon.

On currently known platforms, it's likely possible on su-57/j-36/b-21, but to my knowledge, it wasn't even considered; why? Onboard guidance and autopilot is all round superior.

In the end, F-35 example is telling; it's often used as example, yet it's in fact a very maneuverable 9g jet, which is built for anything but for exploiting high offbore WVR missile combat.
And if there's any such aircraft remaining in modern world, it's the rafale... which isn't particularly new, and is unique, rather than representative of the general trend.

we're talking WVR, not at the edge of sensor effective detection range. the launching platform can also climb (if they don't already come in with positional advantage already being stealthier with better sensors and electronic warfare suit) to extend the event horizon will provide tracking off boresight

again, you're married to the f-35 i'm not. I'm using its system as a base reference for aircraft much superior, a generation ahead in sensor performance. And G pulling isn't just strictly relevant for WVR. BVR maneuvers can be very aggressive to gain positional advantage in term of both energy and stealth. Stealth platform can aggressively reposition itself to regain undetectability or untrackability once its sensors picked up that it's being detected/tracked/

 

[Sferrin]

This looks mean!

What does?

 

[Nicolas10]

What does?

The plane on the picture the post just before mine.

 

[Sferrin]

The plane on the picture the post just before mine.

Ah. The hazards of the ignore list.

 

[Alfa_Particle]

Ah. The hazards of the ignore list.

Ah, seems like someone just can't handle different opinions. A hazardous trait.

 

[SUPER=BUG]

【啥是大运？-哔哩哔哩】 https://b23.tv/b6la3GG

This can be considered an official announcement. In the Easter egg at the end of the video, the crew's conversation hints at the Y-20's role in air refueling for the H-6 and the sixth-generation aircraft (J36).

 

[Sferrin]

Will they sell us some? We could use a decent tanker. (Especially since the USAF, in its infinite wisdom, retired the KC-10s.)