My guess is the air frame is generating so much lift it doesn't need to?
J-20... The New Generation Fighter III
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My guess is the air frame is generating so much lift it doesn't need to?
MiG-29
Banned Idiot
You know , I did had a conversation once with a fellow who knows a lot about Rafale he more or less explain me why Rafale has that configuration , after extensive analysis of both Rafale and Eurofighter we could see Rafale was the better dogfighter , if you mean the Swiss report about Rafale and Eurofighter fighter bid i can posted to you again.
The conclusion has been Rafale is the better dogfighter and Eurofighter the better supercruiser, Eurofighter is more like a XB-70 and J-20 is the same, however J-20 has the great advantage over both designs in the fact it does not carry any weapons externally, which potentially could mean as good as Rafale and Eurofighter.
Close coupled canard will definitively increase lift at high AoA but a long coupled canard like the ones in J-20 will reduce drag, add the lerx and potentially the lift generated by J-20 is potentialy very high; at cruise flight it will be good too.
J-20 is more or less a hybrid of Eurofighter and Rafale in terms of canard wing and fuselage design.
What Song`s paper is saying that canards have to be at the same level of the wing for stealth (you can see that on american JSF concepts with canards) however Rafale`s canards show that having the canard above wing level is okay from the aerodynamic point of view, the Chinese went half way with HIMAT type canards, more or less a compromise between stealth and aerodynamics.
Like Rafale, J-20 has LERXes and wing fuselage blending, but it has a a long coupled canard like Eurofighter, but unlike these two fighters it has no external weapons and warload so this will help it to retain a very high agility loaded, something that does not happen with Eurofighter or Rafale.
The other novelty on J-20 is the V tail, which it self is not new since even F-18 uses it, but this adds some lift generation.
Like Rafale, J-20 also has wing fuselage KARMAN junctions, to reduce drag.
So what the Chinese did was a fighter that compromises in canard position, but thanks to weapons bays, LERX and V tails regains more lift add the wing fuselage blending and it increases lift even more.
The French optimized Rafale making for a very good jet, but it has a critical flaw, it carries weapons externally, thus it needed to be very good in lift generation, but it paid the price in stealth and drag by carrying its weapons externally.
The Rafale as a clean aircraft is a very good design, with mid wings to reduce drag and high close coupled canards, but once it carries them all advantages are highly reduced.
So what you have to see is the way the Chinese have delt with compromises in order to balance stealth with agility
Now F-22 also does not use too much rivets, in fact the aft fusalege of F-22 is welded and F-35 has in a great deal reduced rivets use too.
Read source
Electron beam welding reduces the need for fasteners in some fuselage components by up to 75%, which reduces weight, simplifies the assembly process, and avoids the costs associated with fasteners. The reduction in the number of fasteners also means fewer openings for possible fuel leaks.
If you add TVC nozzles to J-20 then you will increase stealthiness and reduce drag further so the AoA will be increased and supercruise enhanced
So you can see J-20 is a modern jet
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Today's video embedded for your convenience once again:
[video=youtube;lKq1fZou_1Y]http://www.youtube.com/watch?v=lKq1fZou_1Y&feature=plcp&context=C4408bbdVDvjVQa1PpcFPH2_yNOJNNTOkdXV0fnzdA cFrcLVUZsuY%3D[/video]
Workers leveled a dirt mound that J-20 watchers usually stand on when they take pictures of the aircraft.
[video=youtube;lKq1fZou_1Y]http://www.youtube.com/watch?v=lKq1fZou_1Y&feature=plcp&context=C4408bbdVDvjVQa1PpcFPH2_yNOJNNTOkdXV0fnzdA cFrcLVUZsuY%3D[/video]
Workers leveled a dirt mound that J-20 watchers usually stand on when they take pictures of the aircraft.
Equation
Lieutenant General
Today's video embedded for your convenience once again:
[video=youtube;lKq1fZou_1Y]http://www.youtube.com/watch?v=lKq1fZou_1Y&feature=plcp&context=C4408bbdVDvjVQa1PpcFPH2_yNOJNNTOkdXV0fnzdA cFrcLVUZsuY%3D[/video]
Workers leveled a dirt mound that J-20 watchers usually stand on when they take pictures of the aircraft.
Watchers can always bring a step ladder next time.
I am sure they are using them, but as you state that forward fuselage provides lots of lift on its own, also you trim the aircraft to take away pressure, so I'm not quite sure how the FBW handles all that, you notice as siege noted earlier the canards are providing a lot of down force. As you increase the angle of bank you increase the g-load on the aircraft, and hence you have to increase pitch with aft stick. In a 60 degree bank you are pulling 2gs, so a 75,000 pound airplane would then weigh 150,000 pounds, so you have to increase pitch in order to maintain level flight, you usually have to add power as well. The Raptor will maitain 9.5 gs in a steady state as long as you can stand it, these new fifth gen birds have a high bar to measure up to, but those of you who have access to Raptor videos will note the whole airframe often dissappears in the vapor cloud. So I would guess the tallman is pulling 4 to 6 gs, we see vapor/static cloud, but not the whiteout that the Raptor produces, again to remind everyone, he's honkin this thing around, but it doesn't appear to be a max effort, but more photo op. No disrespect intended troupes, but they tend to ease into these things, and things that can break something are a no-no, when you only have one bird. Player have you found any more anecdotal evidence of more aircraft some where else, I don't really have any sources, and I think some of us on here suspect there are more than one, but I have yet to see any conclusive evidence of a little sister to 2001?
---------- Post added 03-11-2012 at 12:04 AM ---------- Previous post was 03-10-2012 at 11:53 PM ----------
I just love you guys, that could be a little obvious, I really hope you guys in the PLAAF will let us keep taking these videos, we just love this thing, I personally think this is the one of the brightest things they have ever done, and this gentlemen is how you sell airplanes to the common man. He can feel the pride of ownership, this is a chinese airplane, and I can't help but notice how excited the folks watching this airplane are about it. It does kinda look like a Kling-on bird of prey. I hope they do let the tall man tell about the flight testing, or maybe tall man is an actor and the pilot is short. I'd like to see two and three so we can see a little more serious flight display, well I better hit the hay, night all, thanks for all your insight, its a lot of fun to watch guys, I really love the pictures even more than the videos which are cool.
Hyperwarp
Captain
escobar
Brigadier
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While I have no clue as to siegecrossbow's quesion, I am fairly sure (by common sense) that the nose and body indeed generate so much more lift than other more normally structured planes...such that the canards always deflect to push down the nose...I know someone explained that they are not meant to push down the nose, but it looks to me to be doing just that.
---------- Post added at 06:15 AM ---------- Previous post was at 05:59 AM ----------
escobar
Brigadier
sorry but it's hard to believe there are 6 to 7 J-20s doing simultaneously different test.
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