PLA next/6th generation fighter thread

[Gloire_bb]

Another hypothesis, one that is more optimistic, is that the PLAAF wants ~70T of total thrust for the 6th-gen aircraft, hence has 3 engines, as even with VCE, one needs 3 engines to get that much thrust.

Flying aircraft meant for 45/70t thrust with 24/40t thrust is kinda pointless. It'll fly like a brick.
At best you can get a scaled down demonstrator.

Also, you don't need VCE to get 20t thrust; there were such engines since 1960s. it's a heavier aircraft, just build a bigger engine.

If it's wc-10, aircraft is most probably meant for ws-15 first and foremost.

 

[sunnymaxi]

@Blitzo is saying that if the PLAAF were very confident in China's aeroengine industry to deliver a 20T+ VCE then they would have designed a plane that assumes they could eventually get there, and hence a twinjet design (since 3x engines = 50% more fuel consumption, a reduced weapons volume, and more airframe weight).

WS-15 maximum take off thrust will be 16-17 tons.. taking minimum. if they designed such kind of engine so 19-20 ton bigger engine shouldn't be the problem. you don't need VCE just build a bigger WS-15 engine to power such a huge aircraft.

 

[Michaelsinodef]

@Blitzo is saying that if the PLAAF were very confident in China's aeroengine industry to deliver a 20T+ VCE then they would have designed a plane that assumes they could eventually get there, and hence a twinjet design (since 3x engines = 50% more fuel consumption, a reduced weapons volume, and more airframe weight).

Another hypothesis, one that is more optimistic, is that the PLAAF wants ~70T of total thrust for the 6th-gen aircraft, hence has 3 engines, as even with VCE, one needs 3 engines to get that much thrust.

70T of total thrust, by the way, would be 2,000kg more thrust than the B-52 bomber. It would enable the carriage of an extremely large fuel, weapons, and sensor payload while still retaining excellent kinematics.

Would such an engine actually allow a 60 ton MTOW plane to have somewhat or even better performance than the J20 (say comparable top speed and super cruise?).

On the other hand, if it's more like 50 ton MTOW (about 25% more weight than J20?), then yes, I do think what he is saying makes more sense.

 

[Blitzo]

Until you know what the design requirements are, this is a strange assumption to be making.

nobody knows if 3 engines is a good thing or not because none of us know what the future air combat looks like. If they do end up using 3 engines, that is more revealing of what they think the future air combat looks like rather than anything else. Or even possibly this just indicates they intend to procure much much fewer of J-XD compared to J-20.

plaaf could entirely get it wrong here by ordering a fighter jet that is too large. We just don’t know.

and usaf may end up picking a design that shows entirely different goals.

You are making this all about engine when it should be a question of how large the aircraft is and how that fits into their overall plan.

I'm not making this all about engines -- rather I am asking people to consider the less appetizing possibility/cause for a hypothetical three engine configuration.

The implicit assumption that a three engine configuration was chosen for the purpose of being more capable, implies that their powerplants and engine industry are of sufficient competitiveness with global peers such that it is unable to attain the requirements of the aircraft they want even with globally competitive engines.

I'm saying that there is a very real and likely possibility that it is because the aircraft itself is not uniquely or disproportionately more capable, but rather their engine industry is unable to meet the capability to power the aircraft with two engines.

 

[AndrewS]

I agree sustaining operations at Guam distance will have a lot of advantages, but there could be other ways to achieve that than maxing range of 6th gen fighter. In term of a 6th-gen FOC, 2030 era all of Pacific conflict, by then China will have additional carriers, long range strike, UCAVs, aerial refuelling, all in much greater quantity than today, plus a large cargo drone fleet, swarming drone dispensers, much better AI targeting, and next gen hypersonic and potentially global prompt strike.

My view is that the 1IC will be secured by 2030, just from the systems already in production today.

Hence they are better off developing the J-XD for operations to the 2IC.

---
For operations to the 2IC, hypersonic missiles with a 3000km range are going to be expensive so they'll always be comparatively rare.
In comparison, jet-powered cruise missiles, piston-engine cruise missiles and potentially CCAs with a range of 3000km will be far lower cost.

But for these lower cost munitions to be effectively used, you need something like air superiority.

then organically use 1IC to push dominance umbralla to Guam.

What does this actually mean?

I think we need to avoid the American mistake of forgeting combat doesn't end when you get there, that's when combat starts. In a 6th gen UCAV heavy networked enviroment it makes no sense to just have a single platform be able to reach 3000 km while others can't. It makes more sense to maximize combat and defensive potential of the manned 6th gen platform while uniformally extending the range across all aircraft.

Yes, the CCAs and missiles also need to have a range of 3000km.

 

[Michaelsinodef]

I'm not making this all about engines -- rather I am asking people to consider the less appetizing possibility/cause for a hypothetical three engine configuration.

The implicit assumption that a three engine configuration was chosen for the purpose of being more capable, implies that their powerplants and engine industry are of sufficient competitiveness with global peers such that it is unable to attain the requirements of the aircraft they want even with globally competitive engines.

I'm saying that there is a very real and likely possibility that it is because the aircraft itself is not uniquely or disproportionately more capable, but rather their engine industry is unable to meet the capability to power the aircraft with two engines.

While that is indeed a possibility.

But it kind of would go against a lot of info that we have gotten in recent years about jet engine progression in China.

Imo, that idea/hypothesis isn't up there to be some 'new base scenario/hypothesis' (a possibility yes, but not big enough to be the base, in case of it actually being 3 engine).

 

[Blitzo]

While that is indeed a possibility.

But it kind of would go against a lot of info that we have gotten in recent years about jet engine progression in China.

Imo, that idea/hypothesis isn't up there to be some 'new base scenario/hypothesis' (a possibility yes, but not big enough to be the base, in case of it actually being 3 engine).

It wouldn't actually go against the info about jet engine progression in China, because while we are all aware they have been making progress, whether the progress is sufficiently globally competitive is a very open question and far from guaranteed.


Anyone who's been doing PLA watching for an extended period of time has known how much the PRC aeroengine/rest of aircraft mismatch has been a consistent pattern. It is very possible this mismatch may continue, or even be exacerbated, for the 6th generation of fighters. It will take a until until we reach a point where PRC aeroengine industry as a whole is at scale sophistication where they don't deserve that level of doubt (think PRC radar industry, or BEV or solar industry etc).

 

[tphuang]

I'm not making this all about engines -- rather I am asking people to consider the less appetizing possibility/cause for a hypothetical three engine configuration.

The implicit assumption that a three engine configuration was chosen for the purpose of being more capable, implies that their powerplants and engine industry are of sufficient competitiveness with global peers such that it is unable to attain the requirements of the aircraft they want even with globally competitive engines.

I'm saying that there is a very real and likely possibility that it is because the aircraft itself is not uniquely or disproportionately more capable, but rather their engine industry is unable to meet the capability to power the aircraft with two engines.

I don't know if that's the implicit assumption, but rather we should wait for the aircraft to come out and judge.

Even if it's larger, that does not mean it's "better". With 3-engine and larger aircraft, you are implicitly going to be buying fewer of them. Which places heavy burden on the capabilities of UCAVs that are expected to operate with them.

Having a 3-engine 6th gen aircraft that might have 3000 km range really seems to raise the expectation on the range and payload of H-20. That has its own implications.

 

[Blitzo]

I don't know if that's the implicit assumption, but rather we should wait for the aircraft to come out and judge.

Even if it's larger, that does not mean it's "better". With 3-engine and larger aircraft, you are implicitly going to be buying fewer of them. Which places heavy burden on the capabilities of UCAVs that are expected to operate with them.

Having a 3-engine 6th gen aircraft that might have 3000 km range really seems to raise the expectation on the range and payload of H-20. That has its own implications.

I'm very much in agreement for waiting for the aircraft to come out -- and again, I am cautiously skeptical at the idea of J-XD having three engines to begin with.

What I am saying people should do however, is to keep at the forefront of their minds that having three engines may not be a "good" thing (i.e.: reflect higher requirements or capabilities or size on an individual per aircraft basis) but may well be reflective of a "bad" thing (PRC aeroengine industry limitations).

 

[tphuang]

J-20 project would indicate they are entirely willing to live with underpowered engine for a long time.

We can kind of guess what WS-15 will be able to do in the 10 year future, probably around 20t in thrust after one major upgrade. 2 of them will be 40t. If we apply another 20% increase on that for next generation engine, that would get us close to 48t for 2.

if PLA thinks that J-XD's MTOW is under 50t, then it would be a bad sign for it to use 3 engines.

But if PLA needs its MTOW to be > 60t, then I don't see how 2 engine is realistic.

Let's do a hypothesis here, if PLA desires a 70t aircraft, then would 2 engine be a realistic configuration?

Without knowing what PLA's requirements are, you cannot say if it's reflective of aeroengine limitations.

If I see 3 engines, then I would expect this aircraft to be huge.

If I see 2 engines, I would expect it to be a little bigger than J-20.