US F/A-XX and F-X & NGAD - 6th Gen Aircraft News Thread

Tomboy

Senior Member
Registered Member
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lifespan, current battlespace, I think further improvements in X-band stealth (stealthy augmenters, exhaust design etc) only result in very minor benefits for fighter-sized aircraft. Far more important will be the electronic warfare space, which favours greater numbers of EW platforms and CCAs. Plus the Chinese Air Force expects to have numerical superiority and to be the one with the initative conducting offensive missions in the Western Pacific, so rear-aspect stealth should be secondary.
I disagree with this, more and more modular and distributed advanced radars being introduced, wideband stealth is extremely important going forward from now on regardless of being the attacker or not. Stealthy augmentors and advanced exhaust designs not only affect X band stealth but also aids in other critical aspects such as IR management. You are far underselling the benefits of these and they aren't even further/future improvements, USAF 5th generation fighters have them as standard from the 00s.

The most likely reason why it was not included with WS-10Cs is simply Chinese material science at the time could not have accomplish this feat as this requires high temperature resistence ceramic RAM and also causes some degree of thrust loss which Chinese engines cannot afford as it was initially barely sufficient in thrust for J-20. WS-15 and WS-19 is expected to have these features along with everything else that comes after for 6th generation fighters.
I recall a Pentagon/USAF comment that it is only a 10% thrust difference between Chinese and American engines.
There are also alot more to engines than static thrust like fuel consumption, hot section lifespan, reliability and performance curve. Chinese engines until very recently were both low performance and low lifespan compared to the best American engines.
 

AndrewS

Brigadier
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So China is ahead in fighter design (and i think we can agree that if someone would have said 10 years ago or even 5 years ago that China will lead the world in fighter design today, most of us we would have seen them as loony fanboys) with two 6th gen airframes and two UADFs which are basically light 6th gen fighters, ahead in avionics since everything suggest widespread GaN radar use, but somewhat behind in engines compared to US. Hopefully the engine hurdles will be overcome too so by next decade China will be at least on par if not puling ahead on engines too.

Like i keep saying, China's current general lead in fighters is theirs to lose, so it will be disappointing if they don't fly a 6th gen carrier fighter before the FA-XX.

It's a GaN on SiC radar on the J-20. So technologically, this is a bit ahead of only GaN.

I think in 2022, it was clear that China would likely pull ahead, as per the USAF briefing which mentioned China developing capabilities 4x faster and having a 20x cost advantage in equivalent hypersonic weapons in the Western Pacific.
 

AndrewS

Brigadier
Registered Member
I disagree with this, more and more modular and distributed advanced radars being introduced, wideband stealth is extremely important going forward from now on regardless of being the attacker or not. Stealthy augmentors and advanced exhaust designs not only affect X band stealth but also aids in other critical aspects such as IR management. You are far underselling the benefits of these and they aren't even further/future improvements, USAF 5th generation fighters have them as standard from the 00s.

But when you have many more airborne radars, it will start to look like a line of aircraft against another line of aircraft.

Or potentially a circle or a v-shaped formation of aircraft.

And given that China will have a significant numerical advantage in the Western Pacific, how will the opposing side manage to get round the side and get a rear-aspect view?

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For the US, it's important to have good rear-aspect stealth (whether radar or infrared), because:

1. Previously, they used to plan on operating over Mainland China, so rearward stealth mattered.
2. Currently, there were/are not that many aircraft in the air, so it is possible for an opponent to get into a rearward position.
3. In the future, they can expect to be significantly outnumbered in the Western Pacific and have Chinese aircraft approach from the rear.

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In comparison, Chinese fighters face a bunch of scattered islands in the Western Pacific (which includes Japan and the Philippines) and aircraft carriers. Chinese fighters have no need to overfly hostile landmasses and expose their rear-aspects. Aside from powered standoff missiles, very low-cost glide bombs with a 120km+ range can pretty much cover every land target, with the aircraft launching safely offshore.


The most likely reason why it was not included with WS-10Cs is simply Chinese material science at the time could not have accomplish this feat as this requires high temperature resistence ceramic RAM and also causes some degree of thrust loss which Chinese engines cannot afford as it was initially barely sufficient in thrust for J-20. WS-15 and WS-19 is expected to have these features along with everything else that comes after for 6th generation fighters.

There are also alot more to engines than static thrust like fuel consumption, hot section lifespan, reliability and performance curve. Chinese engines until very recently were both low performance and low lifespan compared to the best American engines.

I think the the WS-10C having "barely sufficient" thrust is an exaggeration.

On the ground, it just means a slightly longer takeoff run.
In the air, the tradeoff is increased fuel burn for the same cruise speed.
At afterburner, the loss in maximum speed is marginal given the non-linear relationship between thrust and air resistance.

In any case, the lower thrust of the engine can be mitigated, given the very large internal fuel volume of the J-20 and by using external drop tanks.

I think it was just that the designers decided that improvements in rearward stealth (whether IR or radar) weren't that useful and didn't justify the additional cost and also loss in thrust.

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And look at the J-36, which does prioritise all-aspect, broadband stealth with all-moving flexible wingtips.

(That is because it will be operating 3000km+ offshore, where the Chinese Air Force won't have a huge numerical superiority, and will probably have opposing aircraft such as the F/A-XX approach from the rear)

Given that the US doesn't have any development aircraft (not demonstrators) with this feature, China is definitely ahead in this aspect of stealth for 6th gen air superiority aircraft
 
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Tomboy

Senior Member
Registered Member
But when you have many more airborne radars, it will start to look like a line of aircraft against another line of aircraft.

Or potentially a circle or a v-shaped formation of aircraft.

And given that China will have a significant numerical advantage in the Western Pacific, how will the opposing side manage to get round the side and get a rear-aspect view?
Fighters conduct operations normally in circular patrol patterns, which means at some point your rear is going to be facing toward the direction enemy is expected to be. A pacific war is also likely so large in scope as it gets beyond the first and second island chain that enemy sensors could possibly come from anywhere with fighters and support assets stretched thin across the vast ocean. Even if we assume the enemy is only ideally coming from a single direction, retreating after expending your stores will also leave you vulnerable to attacks and detection. While I'd agree with your reasoning assuming the conflicts stays within the Chinese coastal regions and first island chain, this is getting more and more unlikely, for combat beyond the first island chain all aspect wideband stealth and IR stealth should be a priority.

I think the the WS-10C having "barely sufficient" thrust is an exaggeration.

On the ground, it just means a slightly longer takeoff run.
In the air, the tradeoff is increased fuel burn for the same cruise speed.
At afterburner, the maximum speed loss is marginal given the non-linear relationship between thrust and air resistance.

In any case, the lower thrust of the engine can be mitigated, given the very large internal fuel volume of the J-20 and by using external drop tanks.
Remember that the J-20 was originally designed for the 16-18tf class WS-15, anything less that that would've been considered underpowered for the airframe. Even the latest WS-10C2 is rumored to just be scratching the original design thrust of WS-15 nevermind the original WS-10Cs.
 

AndrewS

Brigadier
Registered Member
Fighters conduct operations normally in circular patrol patterns, which means at some point your rear is going to be facing toward the direction enemy is expected to be. A pacific war is also likely so large in scope as it gets beyond the first and second island chain that enemy sensors could possibly come from anywhere with fighters and support assets stretched thin across the vast ocean. Even if we assume the enemy is only ideally coming from a single direction, retreating after expending your stores will also leave you vulnerable to attacks and detection. While I'd agree with your reasoning assuming the conflicts stays within the Chinese coastal regions and first island chain, this is getting more and more unlikely, for combat beyond the first island chain all aspect wideband stealth and IR stealth should be a priority.

If I take Japan as the pacing scenario, the ideal situation would be to conduct daily airstrikes against the ~10 major airbases in Japan for example. You can expect the J-20s to be escorting or conduct air sweeps.

In such a scenario, there will barely be any opposing aircraft in the air.

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It's not credible for any existing fighter to sustain 3000km operations from China to the 2nd Island Chain.
That is what the J-36 is for.
 
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