PLA next/6th generation fighter thread

[iewgnem]

That would require an amphibious operation which is still risky.

Plus that new base would take time to make operational and then have to be continuously supplied.

6th gen won't reach FOC until the 2030s at the earliest, so we have to look at it not from today's naval, amphibous and airforce makeup but from one that's 5-10 years in the future, at which point the power differential between China and US will be much bigger than today.

In the context of full scale war with the US in the 2030s in which all US bases come into play, I think the likelihood of PLA amphibious operation against Pacific islands is not only possible, it's likely, or necessary

 

[AndrewS]

I don't know what their requirements are. I was expecting something closer to 2500km for J-XD and the longer ranged stuff is reserved for H-20.

But if they are actually going to put 3 engines on J-XD, then that hypothesis goes out of the window. Then, they are happy with J-20 and J-35 for within 1500 km. J-XD is then designed to operate up to 2IC or even further if they can get refueled.

Consider all the options China has to project power to a distance of 1500km for the 1IC by 2030.

a) 2000 fighters, of which 1000+ are 5th gen
b) DF-17/DF-16
c) CJ-10 class cruise missiles launched from missile trucks or from H-6s
d) potentially very large numbers of piston-engine cruise missiles

That's almost certainly sufficient to obtain and keep air superiority.

What would a J-XD with a range of 2500km add to the 1IC?

So the next step is to develop capabilities for the 2IC and beyond.

 

[leibowitz]

Just flipping through all the debate here. @Blitzo is your thesis that the Chinese aeroengine industry should be able to produce a 20T class fighter engine in a timeframe sufficient for a twin engine J-XD to be viable, and if J-XD is three engined then that means the PLAAF does not have that confidence?

 

[AndrewS]

6th gen won't reach FOC until the 2030s at the earliest, so we have to look at it not from today's naval, amphibous and airforce makeup but from one that's 5-10 years in the future, at which point the power differential between China and US will be much bigger than today.

In the context of full scale war with the US in the 2030s in which all US bases come into play, I think the likelihood of PLA amphibious operation against Pacific islands is not only possible, it's likely, or necessary

Let's go with your scenario in the 2030s.

How many bases (presumably in the Ryukyus Island Chain) could China realistically conduct an amphibious operation and then hold and resupply? 1?

If China only develops a shorter-range J-XD, then you're looking at a single base versus Guam.

It's a 1vs1 match up, where there is no obvious winner. And we haven't even considered that each US aircraft carrier is essentially an airbase.

---

In comparison, if a J-XD is developed with the range to conduct sustained operations over Guam (3000km away), then you're looking at [20+ Chinese airbases] versus [Guam and perhaps 3 aircraft carriers]

So Guam would be under continuous attack and non-functional as a airbase

US aircraft carriers would also be at great risk if they approach to 3000km, and US Navy aircraft would not be able to conduct air superiority missions to 3000km.

 

[Blitzo]

Just flipping through all the debate here. @Blitzo is your thesis that the Chinese aeroengine industry should be able to produce a 20T class fighter engine in a timeframe sufficient for a twin engine J-XD to be viable, and if J-XD is three engined then that means the PLAAF does not have that confidence?

I wouldn't say it is that specific, rather my caution is that if J-XD ends up being three engined, people should understand that being three engined has a high likelihood of being due to anticipated engine deficiencies rather than due to a greater requirement of J-XD itself.


Or to reiterate from an earlier post -- "there are certain people who seem to view the idea of J-XD being three engined as a "good thing" while I am cautioning that if anything it may be a "bad thing" (if one wants to be more simplistic in the phrasing from a "muh PRC stronk" pov)"

 

[leibowitz]

I wouldn't say it is that specific, rather my caution is that if J-XD ends up being three engined, people should understand that being three engined has a high likelihood of being due to anticipated engine deficiencies rather than due to a greater requirement of J-XD itself.


Or to reiterate from an earlier post -- "there are certain people who seem to view the idea of J-XD being three engined as a "good thing" while I am cautioning that if anything it may be a "bad thing" (if one wants to be more simplistic in the phrasing from a "muh PRC stronk" pov)"

Thank you. That's a good conservative viewpoint. Are there any other hypotheses for a third engine, besides that one?

 

[Michaelsinodef]

I wouldn't say it is that specific, rather my caution is that if J-XD ends up being three engined, people should understand that being three engined has a high likelihood of being due to anticipated engine deficiencies rather than due to a greater requirement of J-XD itself.


Or to reiterate from an earlier post -- "there are certain people who seem to view the idea of J-XD being three engined as a "good thing" while I am cautioning that if anything it may be a "bad thing" (if one wants to be more simplistic in the phrasing from a "muh PRC stronk" pov)"

I still don't completely follow.

Why can't it be because the PLAAF wants such a big increase in capabilities (range, cruising speed, radar size, missile bay size), which translates to a very big increase in MTOW over the J20 (say from the 40ish to 60 tons)?

In which case, a 3rd engine would be needed, even if the next gen engine after WS15 could probably 20-30% more trust than the WS15.

 

[tphuang]

I wouldn't say it is that specific, rather my caution is that if J-XD ends up being three engined, people should understand that being three engined has a high likelihood of being due to anticipated engine deficiencies rather than due to a greater requirement of J-XD itself.


Or to reiterate from an earlier post -- "there are certain people who seem to view the idea of J-XD being three engined as a "good thing" while I am cautioning that if anything it may be a "bad thing" (if one wants to be more simplistic in the phrasing from a "muh PRC stronk" pov)"

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.

 

[iewgnem]

Let's go with your scenario in the 2030s.

How many bases (presumably in the Ryukyus Island Chain) could China realistically conduct an amphibious operation and then hold and resupply? 1?

If China only develops a shorter-range J-XD, then you're looking at a single base versus Guam.

It's a 1vs1 match up, where there is no obvious winner. And we haven't even considered that each US aircraft carrier is essentially an airbase.

---

In comparison, if a J-XD is developed with the range to conduct sustained operations over Guam (3000km away), then you're looking at [20+ Chinese airbases] versus [Guam and perhaps 3 aircraft carriers]

So Guam would be under continuous attack and non-functional as a airbase

US aircraft carriers would also be at great risk if they approach to 3000km, and US Navy aircraft would not be able to conduct air superiority missions to 3000km.

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.

So in a 6th gen, drone heavy and ultra long range hypersonic strike environment, if the goal is to achieve air dominance at Guam distance, 6th gen combat radius requirement could be set to around 1500 km, i.e. eastern Phillipines, maximize ability to secure 1IC bases, use a combination of hypersonic and aerial refueling to extend range to and supress US ops at Guam distances, then organically use 1IC to push dominance umbralla to Guam.

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.

 

[leibowitz]

I still don't completely follow.

Why can't it be because the PLAAF wants such a big increase in capabilities (range, cruising speed, radar size, missile bay size), which translates to a very big increase in MTOW over the J20 (say from the 40ish to 60 tons)?

In which case, a 3rd engine would be needed, even if the next gen engine after WS15 could probably 20-30% more trust than the WS15.

@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.