Chengdu next gen combat aircraft (?J-36) thread

[Andy1974]

Even if the J-36 initial capability is fully limited to only carrying PL-17 missiles internally, and even if it gets its targeting from a KJ-700 it will still be totally lethal against today’s threats.

In its most simplest form, without even power hungry radars, it can still be utterly decisive just by carrying PL-17 internally and shooting based on external input.

It can do this with WS-10C engines, never mind WS-15 or VCE.

Therefore there should be no engine delay at all, and as I just explained there is no need for power hungry electronics for a stealthy shooter scenario, meaning it can be introduced to service very fast.

Full capabilities might be a decade away, but now it can just be a PL-17 truck.

 

[burritocannon]

can we stop talking about missiles in the j-36 thread? is this a place to share what we know about the j-36 or a place to share your daydreams? i really could care less about the latter.

 

[AndrewS]

If you think J-36 design philosophy is to operate way out on its own instead of within an interlinked network, then you don't understand anything at all. Then again, you are also asking about SM-6, which was originally a SAM not AAM, so I guess that goes without saying.

Within the 1st Island Chain, I expect to see in the air realm, in order of expendability/cost/numbers:

1. Piston-engine cruise missiles for ground attack. Very low cost
2. Jet-engine cruise missiles / Valkyrie-type CCAs. Low Cost
3. Larger reusable CCAs. Medium Cost
4. 5th Gen Fighters. J-20 and J-35. Higher Cost.
5. 6th Gen Aircraft. Predominantly J-XDS, but some J-36.
6. AWACs

All these elements will be integrated into a seamless battle network, where the cheapest and most expendable units are used first for the appropriate mission.

We will also see cruise missiles and short/medium-range ballistic/hypersonic missiles being launched from trucks in mainland China.

---

But when you're operating 3000km away at the Second Island Chain, almost all of these air elements will be unavailable. So it will look more like this:

1. Some CCAs
2. J-36
3. H-6 Bombers
4. AWACs

You can see that this will be a very "sparse" battle network with very few launch platforms available.

---

I'm pointing out that the original SM-6 has been converted from a SAM to having a ship/ground-attack role.
And that this was accomplished with a software update, not by changing the hardware.
This should be a straightforward and low-cost thing to do.

As the other guy pointed out, it's possible to modify missiles to service other roles, but expecting them to work just out of the box is ridiculous. There is a reason the AAM/AGM distinction exists and it's not because you are smarter than every air force in the world. Like he also said, you're just arguing for the sake of arguing. I'd advise cutting it out before Deino logs back in; he was already annoyed.

I agree that in an ideal world, you would use a dedicated AAM for air targets and an AGM for ground targets.

But in a world where the weapons loadout is limited, a software update to give an AAM a ground-attack option would be useful and should be an inexpensive software update.

 

[a985010812]

即使歼-36的初始能力完全限于内部携带霹雳-17导弹，即使它由空警-700瞄准，它对当今的威胁仍然具有致命性。

在其最简单的形式下，甚至没有耗电的雷达，它只需内部携带 PL-17 并根据外部输入进行射击，仍然可以具有绝对的决定性。

它可以使用 WS-10C 发动机来实现这一点，更不用说 WS-15 或 VCE 了。

因此根本不应该有发动机延迟，而且正如我刚才解释的那样，隐形射击场景不需要耗电电子设备，这意味着它可以非常快地投入使用。

全面的能力可能还需要十年的时间，但现在它可能只是一辆 PL-17 卡车。

could u tell more about WS17?

 

[Wrought]

Within the 1st Island Chain, I expect to see in the air realm, in order of expendability/cost/numbers:

1. Piston-engine cruise missiles for ground attack. Very low cost
2. Jet-engine cruise missiles / Valkyrie-type CCAs. Low Cost
3. Larger reusable CCAs. Medium Cost
4. 5th Gen Fighters. J-20 and J-35. Higher Cost.
5. 6th Gen Aircraft. Predominantly J-XDS, but some J-36.
6. AWACs

All these elements will be integrated into a seamless battle network, where the cheapest and most expendable units are used first for the appropriate mission.

We will also see cruise missiles and short/medium-range ballistic/hypersonic missiles being launched from trucks in mainland China.

---

But when you're operating 3000km away at the Second Island Chain, almost all of these air elements will be unavailable. So it will look more like this:

1. Some CCAs
2. J-36
3. H-6 Bombers
4. AWACs

You can see that this will be a very "sparse" battle network with very few launch platforms available.

---

I'm pointing out that the original SM-6 has been converted from a SAM to having a ship/ground-attack role.
And that this was accomplished with a software update, not by changing the hardware.
This should be a straightforward and low-cost thing to do.




I agree that in an ideal world, you would use a dedicated AAM for air targets and an AGM for ground targets.

But in a world where the weapons loadout is limited, a software update to give an AAM a ground-attack option would be useful and should be an inexpensive software update.

If you're up against a peer opponent then your sparse network will get eaten alive by their full network, which is why you need tankers, forward bases, and/or carriers to project your own full network out to the relevant battlespace. And if you lack sufficient control within FIC to push your vulnerable support assets up that far, then the answer is to focus on securing that control instead of trying to half-ass a sparse SIC network.

And you missed the point that converting SAMs for ground attack is different from converting AAMs for the same. S-300 for example has also been used in that role. But aside from some brief experimenting with AIM-9X, nobody uses AAMs as AGMs. USAF did not invest in a very diverse AGM arsenal because they lacked AAMs to convert.

 

[Tomboy]

The F-35’s cooling capacity issues have nothing to do with an absence of VCEs and everything to do with a failure to set appropriate requirements for future growth margins for an already volume constrained airframe. VCEs are only talked about as critical for the F-35 to expand cooling capabilities because they’re being offered as a workaround for that first order failure to set appropriate requirements.

There are many many ways to build cooling capacity into an airframe, and VCEs are not the most central factor to that equation. The J-36 has much larger volume and a third engine for a reason. The volume alone (especially the fuel fraction) provides much greater inherent heat sink capacity and the third engine provides much greater heat dumping ability. With or without VCEs the J-36 is already designed to have a much greater amount of cooling capacity than any other fighter in service or development today. If the J-36’s requirements are set to enable its primary system capabilities using WS-15s then the J-36 will perform fine with WS-15s. VCEs are not the critical enabler but the cherry on top here.

WS-15 was not designed with 6th generation air combat in mind and IMO is likely to run into the same issue as the F-135. According to this paper below:

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From the results although fuel system is a big part of thermal management however EFA(Engine fan air) also represents a big chunk of cooling capacity, VCE are designed to provide a large advantage over conventional turbofans in this regard. If J-36 is making potentially big compromises here for WS-15, which I hope isn't the case. As a shift in air combat philosophy, J-36 should be designed to the maximum capability it's intended VCE engines can provide it and not tailored to legacy tech like WS-15. I don't see a reason to rush J-36 into service, USAF's F-47 isn't going to enter service soon anyways as their VCE engine won't be able to make first flight until the late 2020s. China isn't interested on starting a war in the near future either and without 6th gen competition from the US, J-20As and J-35 do perfectly well to keep the US at its bay. @sunnymaxi mentioned that Chinese efforts on VCE technology have been progressing well and should be expected in the next 5-7 years for a service date before mid-2030. Which to me sound perfectly reasonable for a 6th generation aircraft.

 

[latenlazy]

WS-15 was not designed with 6th generation air combat in mind and IMO is likely to run into the same issue as the F-135. According to this paper below:

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View attachment 154025View attachment 154026
From the results although fuel system is a big part of thermal management however EFA(Engine fan air) also represents a big chunk of cooling capacity, VCE are designed to provide a large advantage over conventional turbofans in this regard. If J-36 is making potentially big compromises here for WS-15, which I hope isn't the case. As a shift in air combat philosophy, J-36 should be designed to the maximum capability it's intended VCE engines can provide it and not tailored to legacy tech like WS-15. I don't see a reason to rush J-36 into service, USAF's F-47 isn't going to enter service soon anyways as their VCE engine won't be able to make first flight until the late 2020s. China isn't interested on starting a war in the near future either and without 6th gen competition from the US, J-20As and J-35 do perfectly well to keep the US at its bay. @sunnymaxi mentioned that Chinese efforts on VCE technology have been progressing well and should be expected in the next 5-7 years for a service date before mid-2030. Which to me sound perfectly reasonable for a 6th generation aircraft.

50% larger airframe means 50% more heat sink capacity and 3 engines vs 2 also means 50% more heat dumping capacity *all else held equal*. This would be relative to the J-20. Relative to the J-36 we are talking 200% more heat sinking and dumping capacity (3 times the volume and 3 engines vs 1). Heat capacity and heat dumping rates are linear functions. This is basic thermodynamics. Referring to charts without applying basic physics and engineering principles here will not lead to accurate inferences.

Whether the engine is a VCE is not the critical limiter. The extra heat sinking and dumping capacity from going with a VCE is actually no different from if the engine had a higher bypass ratio. The relevant physical factor here isn’t the variable cycle, but the mass flow volumes of bypass air acting as a heat sinking and dumping medium. You are trying to make VCEs seem like an exotic component of the overall thermal management system when they’re actually not.

If you’re trying to rationalize backwards why the J-36 shouldn’t enter service without VCEs just remember that there are a whole range of tactical employment questions involved in developing a new combat doctrine that you should want to answer as soon as possible if you want to be able to field mature capabilities. Weapons development is not just equipment pageantry.

 

[4Tran]

From the results although fuel system is a big part of thermal management however EFA(Engine fan air) also represents a big chunk of cooling capacity, VCE are designed to provide a large advantage over conventional turbofans in this regard. If J-36 is making potentially big compromises here for WS-15, which I hope isn't the case. As a shift in air combat philosophy, J-36 should be designed to the maximum capability it's intended VCE engines can provide it and not tailored to legacy tech like WS-15. I don't see a reason to rush J-36 into service, USAF's F-47 isn't going to enter service soon anyways as their VCE engine won't be able to make first flight until the late 2020s. China isn't interested on starting a war in the near future either and without 6th gen competition from the US, J-20As and J-35 do perfectly well to keep the US at its bay. @sunnymaxi mentioned that Chinese efforts on VCE technology have been progressing well and should be expected in the next 5-7 years for a service date before mid-2030. Which to me sound perfectly reasonable for a 6th generation aircraft.

While it isn't necessary for the J-36 to be put into service earlier, it does still serve an advantage. If China were to field a significantly technologically superior fighter over everyone else, then it will radically change the rhetoric vis-a-vis the Taiwan question. In Taiwan itself, it might fully silence the pro-independence movement.

Another significant factor is that it can change Japan's stance. Currently, they are the only Asian power in the region with both the strength to affect the Taiwan scenario and where the anti-PLA rhetoric. They are rapidly ramping up military spending but the Japanese hawks can face a big setback if China is seen to have a decisive military edge. Right now, US Indo-Pacific Command relies heavily on its allies in order to be competitive in the West Pacific. The support from these allies is dwindling, and the J-36 is fielded years before the F-47, it has the potential of removing it altogether.

 

[Tomboy]

50% larger airframe means 50% more heat sink capacity and 3 engines over 2 also means 50% more heat dumping capacity *all else held equal*. Heat capacity and heat dumping rates are linear functions. This is basic thermodynamics. Referring to charts without applying basic physics and engineering principles here will not lead to accurate inferences.

Whether the engine is a VCE is not the critical limiter. The extra heat sinking and dumping capacity from going with a VCE is actually no different from if the engine had a higher bypass ratio. The relevant physical factor here isn’t the variable cycle, but the mass flow volumes of bypass air acting as a heat sinking and dumping medium. You are trying to make VCEs more exotic for the overall thermal management system than they actually are.

If you’re trying to rationalize backwards why the J-36 shouldn’t enter service without VCEs just remember that there are a whole range of tactical employment questions involved in developing a new combat doctrine that you should want to answer as soon as possible if you want to be able to field mature capabilities. Weapons development is not just equipment pageantry.

J-36 is projected not only have 50 percent more electrical capacity over the J-20 or even twice the capacity, instead it's projected to have many times the electrical capacity of a 5th generation aircraft. You can't just put a higher bypass turbofan on the J-36 without ruining supercruise efficiency which also is part of the design, VCE could deliver high cooling capacity and efficiency while subsonically cruising while delivering very high supercruise efficiency when needed which is why VCE is called for 6th generation designs. For more efficient dumping heat into the engine, you need engines designed to take hotter fuel then potentially what the WS-15 is designed for while next generation engine would definitely be designed to do

As for developing tactics, I don't see why not to just push out a few LRIP WS-15 powered J-36 to FTTB units to develop new doctrines and not instead start pushing out hundreds of half-baked J-36s with WS-15s as soon as you can as some members here are suggesting. What I'm suggesting is put J-36 into LRIP with WS-15 for a few test units, but they should not start serial production of this type before it is fully ready like what they did with the J-20.

 

[Nevermore]

I predict that Chinese variable cycle engines are unlikely to enter service by 2035. So in order to ensure the timely service of the J-36, it is reasonable to use WS10 or WS15 first.