Interesting. I thought the KJ-600 would be significantly bigger than the fighters, but it looked to be about the same size as the J-15.A rough size comparison.
J-XY/J-35 carrier-borne fighter thread
- Thread starter Deino
- Start date
Maybe more a testament to how big the fighters are.
Like the J-15 is 20 meters! Measure that out in real life, and then realize the E2 Hawkeye on US carriers is according to wiki about 18 meters long.
Oh and by the way, I used your model on the flanker to see just how wrong you were, and the results are… interesting to say the least. The following are your exact words, only with the figures and names changed.
Observe.
“for AL-31F, the max thrust without afterburner is [email protected]/(kN·h), and [email protected]/(kN·h) fuel consumption rate
That means a 6062kg/h fuel consumption for each engine at full thrust. For twin-engine SU-27 it's a doubled 12.1t fuel/h.
Let's assume the engines consuming would be average 80% of max fuel consumption rate during an operation, then it's 9.7t fuel consumption per hour.
Suppose the combat range is 1000km with a 20 minutes stay at the battle field, then a standard operation would take an about 2.5h interval. Then the total fuel consumption would be 24.25 tons.
With 17.5t empty weight and 33t MTOW and 24.25t fuel consumption/2.5h operation, the SU-27 would have 33-17.5-24.25=-8.75t max payload left, with the weight of the pilot and necessary redundant fuel included.”
This is not a very realistic number, is it now?
I think less fuel is needed when flying higher because of the thinner air. Turbofan engines also gives less thrust at higher altitude then at sea level.
Yes exactly, less air mass flow at the intake means less fuel needed for combustion (with a fixed air-fuel ratio) and less thrust. TSFC stays constant in the ideal world, so if less fuel is used then the thrust should also be lower
check #1884 and you'll find that I've made another unclaimed presumption that WS-19 burns only 60% fuel of the RD-93 does, that's why FC-31 would have a POSITIVE payload.
Maybe you could make a 40% fuel consumption off for AL-31 and recalculate the payload parameter for old Su-27?
can you plz elaborate. how can you compare 80's made engine with WS-19 ? even you know that, manufacturing and metallurgy process are way more efficient now.check #1884 and you'll find that I've made another unclaimed presumption that WS-19 burns only 60% fuel of the RD-93 does, that's why FC-31 would have a POSITIVE payload.
Maybe you could make a 40% fuel consumption off for AL-31 and recalculate the payload parameter for old Su-27?
I’m not wasting my time doing your work based on another completely unjustified claim mate. The method of estimation is wrong, that’s all there is to it. If you actually do want to get a somewhat accurate estimation then you’ll need detailed mission profile, L/D diagrams of the aircraft in question as well as thrust and TSFC diagrams of engines included. Without these information our calculations are merely guesswork, I even hesitate to call them educated guesses since the method of calculation is so far off the proper way of doing it.check #1884 and you'll find that I've made another unclaimed presumption that WS-19 burns only 60% fuel of the RD-93 does, that's why FC-31 would have a POSITIVE payload.
Maybe you could make a 40% fuel consumption off for AL-31 and recalculate the payload parameter for old Su-27?
p.s. having a positive payload based off your calculation is no indication that it’s anywhere near the ballpark of being correct, and while randomly changing the percentage of fuel consumption that you think should be used may give you results that look plausible, that does not indicate the results are in any way true. If I were you I’d simply stop this pointless and tbh fruitless campaign of trying to justify that the J-xy either doesn’t exist, isn’t the actual naval stealth jet or that it’s not up to the job. With nearly no public information to go off of you’ll merely make a fool of yourself and waste everyone (including yourself)’s time. Give it time, and when we have data then we can discuss.
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Nobody here would have the accurate performance data of military engines and aircrafts, so all the discussions here are based on simplified and inaccurate model. I don't think anyone would have the privilege to underrate the opinions of the other and declare a victory.
WS-19 is, or should be, definitely better than RD-93, but it would not be a fairy tale.
For the 4th gen. fighters, most payload were hung under their wings or main frame. But for the 5th gen. stealth fighter aircraft, the request to load all the fuel and weapons within internal tanks and weapon bays would request them to be bigger, with larger volume/size ratio.
Also, since all the Chinese military avion enterprises share most of the achievements of engine technologies, if WS-19 could be supposed to have such huge progress from RD-93, then why can't we suppose that the new batch of the WS-15 engines were also greatly increased in their performances?
FC-31 or 35 would be a legend only when you overestimate the performance of WS-19 but underestimate that of the WS-15.
WS-15 was always be estimated 15t thrust and 1.6t weight, with a T/W ratio of a bit less than 10.
But the most exaggerated estimation for WS-19 is 12t thrust and a same 1.06t weight as RD-93, a legendary TWR of 11.5!
Obviously, only in this way can the fc-31 surpass the j-20 in performance. But how could that be possible?
“Nobody here would have the accurate performance data of military engines and aircrafts, so all the discussions here are based on simplified and inaccurate model. I don't think anyone would have the privilege to underrate the opinions of the other and declare a victory.”
Exactly. There is no accurate data and there is literally no good way of modeling our current topic in the absence of accurate data, which has always been my point. This isn’t really about victory IMO, it’s about your claims being unjustified and your model being outright wrong. I’m trying to point this out, not to achieve any form of personal “victory”.
As for the performance, no one here
has claimed that the fc-31 has better range/payload/speed/TWR than the J-20, the way I see it it’s you who brings these up and makes an effort to deny them. If you have a problem with those who overstate the performance of fc-31 then go bring it up directly with them, instead of trying to prove that it’s not good with very little evidence in one direction or another. As I said, give it time and we can discuss when we have more data on our hands.
Now can we just accept that the calculations in question is fundamentally flawed and there’s currently no way of getting a reasonably good estimate of the range, fuel requirements and payload of the J-xy?
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