4 rivets on each nozzle petal and 2 rivets on each sealing petal is the signature of WS-10.
J-20 5th Gen Fighter Thread VI
- Thread starter siegecrossbow
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Canard vortices probably kick in fully only at high AOA. The Eurofighter AMK re-design shows that long-coupled + lerx + delta does work.
@Bltizo
Still going through previous responses, but let me mention again the J-20 isn't described as an air superiority aircraft, but rather as a heavyweight stealth fighter, which can "seize and maintain" air superiority, although I'll point out that air superiority and air superiority aircraft are two separate things.
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Let's point out the evidence first.
-J-20 has failed to show exceptional maneuverability in videos shown; best is a roughly 22-30 degree ITR turn at around 5000m of altitude, which is STR, and under afterburners as well.
-There's design docs from the original J-20 aerodynamic formula design that indicate why the LERX-Canard-LERX-Delta format was chosen, and it states that supermaneuverability was a goal.
-There's a document that says that the J-20 is a "heavy" stealth fighter, which is little more than a discussion of its weight class, but also that the J-20 is, in the order listed, aimed to seize air superiority, maintain air superiority, intercept enemy aircraft, then escort strike / bombers.
-The J-20 has WVR missile bays.
-But the J-20 also lacks a gun.
-The J-20 has weapons bays roughly comparable to the F-35, but it can't fit in current Chinese anti-ship and anti-radiation missiles, much less the PL-21/PL-XX that's designed for interception.
-Claims by PLAAF pilots have said that while the J-20 has decent (not bad, good, etc) performance subsonically, it has excellent performance supersonically.
-Claims by PLAAF pilots have said that the J-20 apparently beat Chinese domestically produced fighters in speed testing, implying that it has a higher top speed than any other Chinese aircraft in production.
This is essentially the direct evidence. More indirect evidence goes to the changing nature of modern warfare.
-The F-35, for instance, is not designed to out-dogfight an F-16 or match the F-22 in agility. It is designed for excellent ITR, but its STR is known to be questionable.
-Modern WVR missiles make it extremely difficult for dogfighting to be anything other than attritional warfare, given super-agile IR seekers that can reach 20km of range.
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The biggest difference in our perspectives is that I'm trying to guess at what modern stealth vs stealth warfare is going to look like in the future, i.e, I'm working more from the indirect evidence given.
Your point is that the design docs claim that the J-20 is designed to be supermaneuverable, when, first, supermaneuverability refers specifically to maneuvers in the post-stall range (i.e, ITR), and second, high maneuverability in a traditional dogfight setting is of questionable benefit in modern warfare when WVR missiles are making the WVR sphere suicide. From this perspective, we can reread what the evidence is showing us.
-The J-20 is designed for supermaneuverability. But that's an ITR factor (and 22-30 degree ITR has been demonstrated at altitude), and ITR is less relevant in dogfighting than STR.
-The J-20 is described as good, i.e, not outstanding as the F-22 or Su-57 might be, in terms of subsonic maneuverability.
-The J-20 has failed to show exceptional subsonic maneuverability during airshows and so on.
-The J-20 is described as having outstanding supersonic maneuverability and very high top-speeds.
Going from this, we can suspect that dogfighting is addressed, but not a priority on the J-20.
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But then again, we get back to repeating ourselves. You want the J-20 to be outstanding as a dogfighter. I don't care whether the J-20 is an outstanding dogfighter as long as it's a reasonable threat to the F-22 (in numbers) and capable of getting strong K
vs the F-35.
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Please Inst ... stop this again and again opening up old issues. It is annoying and must stop.
Take this as a warning
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Not really sure if this could be regarded reliable.
Hyperwarp
Captain
That is very out of date.
The thrust range of the WS-10 was displayed during a Zhuhai airshow (2014?) to be between 12,000 kgf and 14,000 kgf. That means max thrust of 137 kN. I recall @Interstellar saying at PDF that the 137 kN verision is the WS-10IPE (correct me if I am wrong).
Equation
Lieutenant General
So I think we heard through leaks that WS-10B was a hair under its goal of 135kN. Given that, I would think that it makes very little sense to have an IPE at only 137kN.
So in order to justify testing J-20 for a new engine (WS-10), it would have to either be a political reason or it would have to be because it brought significant advantages in performance. Given China's excellent relationship with Russia now, and given that China no longer feels "reliant" on or "chocked" by AL-31 since it can make its own comparable engine, I would say that there is no political reason to switch engines now. Let's examine the possibilities as they pertain to the performance aspects:
1. The new WS-10X is a variant with comparable wet performance to the AL-31FM2 but with significantly better dry performance.
The likelihood of this scenario is increased by the assumption that the best known thrust for operational WS-10 is 134kN on WS-10B. So it is likely that a next-in-line variant wouldn't jump too far above that in wet thrust, keeping it in the mid-low 140kN range. However, is it worth the trouble of engine testing to integrate a variant only for some dry thrust increase to enhance range and supercruise?
2. The new WS-10X is a variant that comes with enhances thrust at the expense of engine lifespan.
The likelihood of this scenario is increased by the fact that it is likely the easiest way to improve thrust, by not really advancing technology, but sacrificing A for B on the same level of technology. However, is it worth the trouble of testing and integrating a new engine? This sounds like more of a last reserve option if conflict is seen to be imminent and so far, we the plebeians, don't see that. Is it wise for China to spend effort on side-ways development of temporary stopgap products when the effort could be spent on true advances?
3. The new WS-10X is an enhanced variant, superior in every way to older variants and to the AL-31FM2 that is supposedly on J-20.
Is this the long-rumored but never substantiated 155kN WS-10G? If WS-10B's 134kN was the last best engine, then that would be quite a jump in performance. It would certainly be worth the effort of engine testing and to happily begin serial production beyond LRIP until 2025's WS-15. Of course the engine could be superior to AL-31FM2 but not so much as 155kN (which would provide 20kN more to the final thrust) but we then need to revisit the question posed in 1 and that's how much of a performance boost is worth testing a new engine? It's not 2 or 3 kN...
Image confirms J-20 fighter assigned to PLAAF combat unit at Wuhu
Andreas Rupprecht, Mainz - Jane's Defence Weekly
01 August 2019
Chinese state-owned media have for the first time released an image of a J-20 fighter bearing the serial number of a known combat unit of the PLAAF. Source: Via cctv.com
Chinese state-owned media have for the first time released an image of a Chengdu Aircraft Industry Group (CAIG) J-20 fifth-generation multirole fighter bearing the serial number of a known combat unit of the People’s Liberation Army Air Force (PLAAF), suggesting that the aircraft is ready for frontline service.
The image, which was released by state broadcaster China Central Television (CCTV) in late July, shows the aircraft bearing the number 62001, indicating that it has been assigned to the PLAAF’s 9th Air Brigade based at Wuhu, which operates under the PLA’s Eastern Theatre Command.
Commercial satellite imagery captured in March 2019 showed three J-20s at Wuhu Air Base, suggesting that the aircraft have been operating there since early 2019 or late 2018. It is likely that the fighters are replacing the Su-30MKKs assigned to the 9th Air Brigade, which is believed to be one of the premier fighter units within the PLAAF.
Wuhu Air Base is situated near the Yangtze River approximately 280 km inland from Shanghai. The base is home to the 7th and 9th Air Brigades. The 9th Air Brigade received the Su-30MKK in 2001.
Assigning the J-20 to such a combat unit is a significant move because the two previous PLAAF units known to operate the J-20 were related to operational evaluation and tactical training.
As Jane’ s previously reported, the 176th Air Brigade at Dingxin Air Base is the operational test unit used to evaluate the J-20 and develop tactics, and the 172nd Air Brigade at Cangzhou Air Base is the initial training unit for training instructors and developing training material.
Andreas Rupprecht, Mainz - Jane's Defence Weekly
01 August 2019
Chinese state-owned media have for the first time released an image of a J-20 fighter bearing the serial number of a known combat unit of the PLAAF. Source: Via cctv.com
Chinese state-owned media have for the first time released an image of a Chengdu Aircraft Industry Group (CAIG) J-20 fifth-generation multirole fighter bearing the serial number of a known combat unit of the People’s Liberation Army Air Force (PLAAF), suggesting that the aircraft is ready for frontline service.
The image, which was released by state broadcaster China Central Television (CCTV) in late July, shows the aircraft bearing the number 62001, indicating that it has been assigned to the PLAAF’s 9th Air Brigade based at Wuhu, which operates under the PLA’s Eastern Theatre Command.
Commercial satellite imagery captured in March 2019 showed three J-20s at Wuhu Air Base, suggesting that the aircraft have been operating there since early 2019 or late 2018. It is likely that the fighters are replacing the Su-30MKKs assigned to the 9th Air Brigade, which is believed to be one of the premier fighter units within the PLAAF.
Wuhu Air Base is situated near the Yangtze River approximately 280 km inland from Shanghai. The base is home to the 7th and 9th Air Brigades. The 9th Air Brigade received the Su-30MKK in 2001.
Assigning the J-20 to such a combat unit is a significant move because the two previous PLAAF units known to operate the J-20 were related to operational evaluation and tactical training.
As Jane’ s previously reported, the 176th Air Brigade at Dingxin Air Base is the operational test unit used to evaluate the J-20 and develop tactics, and the 172nd Air Brigade at Cangzhou Air Base is the initial training unit for training instructors and developing training material.
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