b787 tends to either involve his wife or women (and his kids) in every single discussion for whatever reason ... not surprised he brought up these weird women comparisons.
J-20 5th Gen Fighter Thread VI
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vesicles
Colonel
I'm still waiting for that number...
@Figaro: we redid the numbers and it looks definitely like 73 m^2 wing area. We could be even more condescending: on stable aircraft, which as we understand the J-20 is not, canards add lift while canards subtract from lift. On unstable aircraft canards subtract lift while tails add lift.
Moreover, if you go about twenty to thirty pages back, we went over Chinese pilots using simulators of the J-20B. They were headily discussing the TVC on the J-20B. Most of this TVC bashing by Engineer and others is because China did not possess TVC technology, and now with the Su-35 and WS-15, China does possess TVC.
You have to remember, the J-20 will be the first operational canard aircraft with TVC, but the J-20 is not the first to have tested the paradigm. The Eurofighter experimented with TVC, but the project was ultimately shelved due to weight, maintenance, and cost issues. The X-36 aircraft by the Americans found that a tailfinless canard delta utilizing TVC had significant stealth, maneuverability, and drag advantages over conventional aircraft. This is where the J-20 is heading to, it's just that development is too delayed to seriously attempt the tailfinless variant.
Moreover, if you go about twenty to thirty pages back, we went over Chinese pilots using simulators of the J-20B. They were headily discussing the TVC on the J-20B. Most of this TVC bashing by Engineer and others is because China did not possess TVC technology, and now with the Su-35 and WS-15, China does possess TVC.
You have to remember, the J-20 will be the first operational canard aircraft with TVC, but the J-20 is not the first to have tested the paradigm. The Eurofighter experimented with TVC, but the project was ultimately shelved due to weight, maintenance, and cost issues. The X-36 aircraft by the Americans found that a tailfinless canard delta utilizing TVC had significant stealth, maneuverability, and drag advantages over conventional aircraft. This is where the J-20 is heading to, it's just that development is too delayed to seriously attempt the tailfinless variant.
Get ready to wait forever.
J-20 designers wanted to minimise frontal RCS so it makes sense to minimise surfaces that will reflect radar. Every aspect of this plane shows high attention to detail for the aim of achieving stealth. Even the rear aspect looks fine. It does need new petals though. Maybe something like the F-35's will show up when WS-15 is revealed.
Exactly why the TVC skeptics among us prefer no TVC unless they've really nailed it down. TVC probably isn't necessary for J-20. Every last Newton of thrust is though.
The size of what is arbitrarily called “wing” is not all that important. The important thing is the lift coefficient of the entire airframe and the maximum lift the airframe overall can generate. A plane with small wings but with a fuselage shaped to maximize its own lift coefficient could easily have better lift coefficient overall and higher maximum lift than a plane with big wings but with fuselage that provides little lift compare to its own drag.
Many modern fighters gets more than half of their lift from their fuselage. They can literally fly, and have flown, with their wings snapped off.
Unless you know the overall lift coefficient and maximum lift of the su-27 airframe vs j-20 airframe, you don’t have a real story to tell by eyeballing the size of the wings.
vesicles
Colonel
You see, the problem is someone claims that the wing area is the only thing that matters. Yet, he refuses to provide the actual evidence to back himself up.
I don't think the conversation is very constructive. Can we lay off the speculations and look at the discuss hard facts/images instead? Thanks.
Ougoah: I'd think the maintenance was the main r Ieason the Eurofighter skipped TVC. It's very wonky to work with, and while Western engines have exceptional MTBO, TVC means you'll have to do frequent maintenance with the TVC system. It also gives you more points of failure: a TVC system can lock up on you, leaving you with only one engine to work with.
Regarding measurements, if you do wingtip to wingtip, ignoring the pylons, you get 134 pixels. That gives you about 13.1 or 13.2 meters on the J-20's wingspan, but it does give you 21.5 to 21.83 meters on the J-20's length. On the plus side, we get a radome diameter of 1.3 meters, giving us either a 1 m^2 radar aperture based on 25% diameter reduction or a 1.2 m^2 aperture based on 10% diameter reduction.
For wing area, assuming it's 96 pixels from the front apex of the wing to the back apex, then adding 18 pixels for the trapezoidal area, then scaling by 14.7 * 14.7 / 134^2, we get about 77.8 square meters.
So yes, the J-20 is actually pretty large, on the scale of the Flankers. This implies that it has a larger volume than previously estimated, about 1% larger by area. But it also has a robust wing area to compensate. If weight is really as low as claimed, only at ~16000 kg, with fuel and weapons load at 12500 kg, we get 370 kg/m^2 loaded and 307 kg/m^2 at 60% fuel. These aren't bad abstract figures, but we still have the strangeness of "good" subsonic maneuverability.
Regarding measurements, if you do wingtip to wingtip, ignoring the pylons, you get 134 pixels. That gives you about 13.1 or 13.2 meters on the J-20's wingspan, but it does give you 21.5 to 21.83 meters on the J-20's length. On the plus side, we get a radome diameter of 1.3 meters, giving us either a 1 m^2 radar aperture based on 25% diameter reduction or a 1.2 m^2 aperture based on 10% diameter reduction.
For wing area, assuming it's 96 pixels from the front apex of the wing to the back apex, then adding 18 pixels for the trapezoidal area, then scaling by 14.7 * 14.7 / 134^2, we get about 77.8 square meters.
So yes, the J-20 is actually pretty large, on the scale of the Flankers. This implies that it has a larger volume than previously estimated, about 1% larger by area. But it also has a robust wing area to compensate. If weight is really as low as claimed, only at ~16000 kg, with fuel and weapons load at 12500 kg, we get 370 kg/m^2 loaded and 307 kg/m^2 at 60% fuel. These aren't bad abstract figures, but we still have the strangeness of "good" subsonic maneuverability.
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manqiangrexue
Brigadier
Ohhhhh, guys, I knew B787 was gonna start talking about ladies and his kids once he gets cornered on the relevant topic. Did I call it or did I call it? I'll refer you to this:
https://www.sinodefenceforum.com/j-20-5th-gen-fighter-thread-vi.t8169/page-66#post-480142
Hey, B787, do you home school your kids in math? With your mastery of numerics, I'd assume your lessons go like this: "Small + small = medium. Medium + medium = large. Medium + small = larger than medium. If you have some oranges and your sister has some oranges, together, you have a lot of oranges!" LOLOLOL
https://www.sinodefenceforum.com/j-20-5th-gen-fighter-thread-vi.t8169/page-66#post-480142
Hey, B787, do you home school your kids in math? With your mastery of numerics, I'd assume your lessons go like this: "Small + small = medium. Medium + medium = large. Medium + small = larger than medium. If you have some oranges and your sister has some oranges, together, you have a lot of oranges!" LOLOLOL
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