Chinese Engine Development
- Thread starter jackbh
- Start date
Quickie
Colonel
You accept any random information from a random site as something of a fact?
I read through the first few paragraphs but can't continue anymore because the BS lightbulb keeps flashing on.
"From a testing perspective, the engine has also been found on several J-10Bs and J-20As." - referring to WS-13.
Has WS-13 been tested J-20 or J-10B ? That is news to me. I'd also point out that the article cites "sources" without clarifying who or what these sources are.
Many things like "WS-15 exploding during testing in 2015" is supposedly true. But it also misses some "rumors" of WS-15 already being tested on J-20. How can an engine that failed ground rig tests (catastrophically) be integrated into a cutting edge airframe. A J-20 crashing would have serious implications politically as well as socially for the Chinese.
One would have stopped reading the article once reading "cannot supercruise without using afterburner". This means that the author does not know what he/she is talking about. Equating super-cruising with high dry thrust is basic non-sense. Higher dry thrust means higher acceleration (changing of speed) without afterburner, lower dry thrust (AL-31, WS-10) ONLY means that the aircraft will take longer time to reach supersonic speed without using afterburner, but still can super-cruise. To sustain super-cruising, the only requirement is the dry-thrust being higher than the drag. Basic physics is that speed is not acceleration which the author seems have not learned in school. He/she certainly did not go to engineering college.
SamuraiBlue
Captain
Speed does not work like that.
Drag is resistance against acceleration. If you cannot accelerate beyond the speed of sound (Mach1) it means you cannot super cruise simple as that.
It's the same as top speed of a car.
For a car to reach a certain top speed the first thing it requires is a low weight to power ratio. Next you need enough power to push the plane to that speed.
Drag in real life is not just resistance against acceleration. It is a resisting force against motion including an object with constant velocity. It works similar to how friction would because it is essentially air friction or air particles pushing against the plane and since air is turbulent, there are forces involved there also. Just because an object does not have any thrust forces applied on it, it still gets slowed down by friction or drag. Surface friction varies depending on material surface properties and air friction varies depending on altitude, temperature, and pressure... speed of object is obviously going to factor in here and so will the lift characteristics of the airfoil. This is why our coefficients change depending on these factors and the problem is rather too dynamic to describe in a sentence.
The Su-27, J-11, J-10, J-20, J-16 and others can all go beyond mach 1. Therefore their engines can accelerate the fighter beyond mach 1. So when you say the following:
"If you cannot accelerate beyond the speed of sound (Mach1) it means you cannot super cruise simple as that."
Does that mean you can supercruise if you can accelerate to a speed that is above mach 1? Because those fighters can and we know su-27, J-11, J-10, and J-16 apparently cannot supercruise (this is from our speculation and absence of official statements saying they can). So what do you mean by the parts in bold?
You're actually using words to say absolutely nothing here. If you know, tell us how something can supercruise. Everyone here knows that if a plane cannot reach mach 1, it cannot supercruise. That is essentially the definition. In your second part you seem to suggest that supercruise is a function of thrust to weight. This is also an incomplete picture. You can have amazing thrust to weight but have the aerodynamics of a bus and almost no lift. That's going to hurt your ability to supercruise.
Taxiya is correct in saying that the author doesn't know shit if they are suggesting that something cannot supercruise without using afterburner. There is nothing wrong with what Taxiya wrote and I feel either you guys misunderstood or are just too dull for words because you failed to see what Taxiya meant. Very simple honestly. I'm seeing a pattern with people lol...
To hold your hands here's the answer. If someone says "cannot supercruise without using afterburner", it's a meaningless statement because supercruise means no afterburner so that statement doesn't work. Instead they ought to say "cannot supercruise". But including that second part proves they are not well informed about these subjects at all.
On the interesting points Taxiya raised about reaching supersonic speeds with only dry thrust. He is more or less correct except breaking the sound barrier imposes a dramatic increase in drag. This means the aerodynamics of the fighter comes into greater play. Since we don't know the specifics here and we can't eyeball it, it's impossible to say whether or not the flanker series can supercruise even if their engines are not stopping them from doing so.
For the J-20, it's even harder to know about its ability to supercruise and how effectively and efficiently it can do that. This author, failing to understand supercruise, proves they have even less of a clue and since no leaks are around, we can conclude that report to be utter BS. In fact the only "official" hints to J-20's ability is that it is optimised for supersonic flight and fights. It is also designed to counter F-22 and F-35, I think supercruising is very much on the cards here. But who knows. It seems to have much less drag and more lift than flankers and if Su-35 with 117S can supercruise apparently, then there should be no hindrance to J-20 even with AL-31 or WS-10.
Last edited:
SamuraiBlue
Captain
Without afterburner?
I doubt it and if it can't then it can't supercruise. Simple as that.
To maintain speed within constant resistance(drag) against a moving object means it requires constant acceleration.
Correct. This is why I described continued supersonic speeds as a different problem to just thrust to weight ie a thrust issue for these fighters.
Since we don't understand the aerodynamic profiles of flanker and J-20, we shouldn't speculate. This author of the article is in a more ignorant position.