Although not strictly J-20 related, since it keeps getting mentioned on this thread...SCMP was bought by Alibaba last year. So it hardly counts as an anit-China paper! It was owned by some friends of mine before that, who if anything are slightly pro China. Of course that does not mean the reporting is any better for it. But there is plenty of inaccurate reporting without having to resort to inaccurately saying SCMP is anti-China. It simply has a reporter who, like us, uses what she can find (except her grasp of details is far lower than this forum's members!).
J-20 5th Gen Fighter Thread VI
- Thread starter siegecrossbow
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SCMP has always tried to maintain a diversified set of views in its editorial decision making and reporting. That said, their reporting on Chinese military matters has never been very good, and I imagine a big reason why is that it’s very difficult to get reliable Chinese military industry insiders as sources when this sector is state managed and the information is so sensitive and controlled. In such an information scarce beat the people who do have a lot to say are either themselves more likely to be misinformed, or else have some kind of ulterior interest or narrative they want to push. At the same time, a newspaper’s business is to push content, so they’re going to end up publishing whatever they can get.
SCMP is not as anti-China as you would expect, although I do have skepticisms for the "anonymous" sources like you do. I just want to hear how y'all will argue against what has been stated in the article, especially the accusation that J-20 can't really supercruise.
The supercruise claim in the article is just a recycled belief that comes from a simplistic laymen understanding of how supercruise is achieved. It’s not a claim built on any actual understanding of physics. The truth is you can’t tell anything about whether a design can cruise at supersonic speeds with just its dry thrust by looking only at how powerful the engines are or looking at the T:W ratio.
In an atmosphere all objects hit their top speed when the force propelling them forward matches the force of air resistance pushing them back, so that their acceleration nets to zero (if this sounds familiar to some people that’s what terminal velocity is).*** Thrust tells you how much force you have to push an object forward, *but* it doesn’t tell you how much air resistance that object will need to overcome. The force of air resistance goes up as the speed of the object increases, but *how* much it goes up by depends on the density of the air, a drag coefficient which is defined by the *specific* shape of the object, and the frontal area of the object along the face it is traveling forward in.
If you have two objects of the same volume but they’re shaped differently (and maybe have different surface treatments), some combination of different frontal area and different drag coefficients means that one can have a lower air resistance curve than the other at the same speed, and can thus hit a higher top speed with the same amount of thrust (I’ll leave air density and altitude out of this explanation, but if you jut think about it a bit how they factor in is pretty straightforward). There’s an additional complication once you hit the transonic and supersonic regime because the drag coefficient changes, but the same principles hold. What this means for our particularly discussion here is that if a combination of the J-20’s drag coefficient in the supersonic regime and frontal area keeps the overall force of air resistance lower than the total amount of dry thrust its engines can generate, it can supecruise (or, if we define supercruise more narrowly being able to effectively engage in cruise flight in the supersonic regime, it can go supersonic without afterburners).
Seeing as the drag coefficient can’t be eyeballed, no one can know with any claim to honest fact whether the J-20 with interim engines can supercruise unless someone sticks a J-20 model into a wind tunnel or a CFD simulation and tells us that to be the case with very detailed aerodynamic analysis. What we *can* say is that even if it can supercruise, or at lesser reach supersonic speeds, with its interim engines it can probably supercruise better with more powerful engines, and whatever its performance in that envelope of flight is right now it would almost undoubtedly be better with better engines. In addition, we do know that at least the original design study of the J-20 said its basic design would allow supercruise with weaker engines, and we now have at least some circumstantial evidence from the stories about these traininf exercises that the J-20 can indeed hit supersonic speeds with just its dry thrust, and perhap employ effective supersonic maneuvers for combat powered under dry thrust.
The other stuff in the article you shared about “setbacks” because the intended engines aren’t ready is just (I would go as far as to say shameless, disingenuous, and morally self indulgent) spin over basic information that’s already been known about for years (except the claim referencing back to the SCMP piece about the WS-15 exploding during testing in 2015, which we’re all still a bit dubious about since we don’t have ways of substantiating the claim), hence the dismissive response of many members in this forum.
***There’s an additional factor that can limit top speed with objects powered by jet engines, where the speed of the airstream going into the engine inlet matches the speed of the airstream the engine can push out, since if the speed of the airstream going in is as fast as the speed of the airstream going out then no more work (and thus thrust) can be extracted from the airstream, but we can ignore that when discussing most jet fighters that are designed to go supersonic.
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Oh okay I had no idea it did have a gun port. Guess I bought into the bogus claims by the typical crowd.
The article being discussed is actually a Business Insider piece that uses some reporting from another SCMP piece and puts some colour around it.
Many of us have selective memory. There are plenty of media outlets we would generally regard as pro-west and anti-russia, china, etc but they can and have been unrealistically harsh and unfair on western military projects. They've done it to the F-35 and even the F-22 before that. Occasionally journalists who have been exaggerating the abilities and threat of a nation's military sometimes turn 180 degrees and put up a piece about how weak and ineffective the same military is. It's just a way to hedge the bet and play to all sides of the spectrum and get most attention and audience whether it's praise, hate, confirming one's dogma or questioning it. It is how most media works (state run or otherwise). None of them can be considered reliable and none of them are academic in nature so are about as good as toilet paper.
Whatever the developments, revelations, outcome of war etc, these media slimebags will always point to one or many of their articles and say we told you so. They WERE really scary and strong/ weak and hyped up.
Whatever the developments, revelations, outcome of war etc, these media slimebags will always point to one or many of their articles and say we told you so. They WERE really scary and strong/ weak and hyped up.
timepass
Brigadier
China appears to have rushed its J-20 stealth fighter into service with an 'embarrassing' flaw
"Chinese state media announced on Friday that the Chengdu J-20 stealth jet had officially entered into service as a combat-ready platform - but inside sources say it's a long way from fighting fit and has an embarrassing flaw.
Citing military sources with knowledge of the J-20's development, the South China Morning Post reported that the jets that entered service didn't feature the engines China custom-built for the platform but used older ones instead.
The result is an under powered, less stealthy jet that can't cruise at supersonic speeds and is therefore not a true fifth-generation fighter."
"Chinese state media announced on Friday that the Chengdu J-20 stealth jet had officially entered into service as a combat-ready platform - but inside sources say it's a long way from fighting fit and has an embarrassing flaw.
Citing military sources with knowledge of the J-20's development, the South China Morning Post reported that the jets that entered service didn't feature the engines China custom-built for the platform but used older ones instead.
The result is an under powered, less stealthy jet that can't cruise at supersonic speeds and is therefore not a true fifth-generation fighter."
Thanks a lot, man! Really Appreciate it!
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