It’s the only known aircraft to have performed the tumble climb. It has good controllability at high AOA. If they didn’t want that then they wouldn’t have used ventral strakes.
J-20 5th Gen Fighter Thread VIII
- Thread starter Blitzo
- Start date
It’s the only known aircraft to have performed the tumble climb. It has good controllability at high AOA. If they didn’t want that then they wouldn’t have used ventral strakes.
It’s been like 13 years since we all read Dr Song’s paper. Hey did all our Chinese get better since then.
Do they have TVC? If not how are you so sure?
That looked more like a failed attempt at a clean unloaded roll than some sort of deliberate maneuver to me. J-20s have a tendency to deviate their longitudinal axis from their velocity vector when rolling, aka "tumbling", and to my understanding this isn't a good thing because it hinders roll rate and bleeds off more energy
Do you have a video of the J-20 pulling high AOA? I can't seem to find any where it does, at least compared to the F-22 and Su-57 which can both casually pull 90+ degrees
No variant of J-20 has TVC. The design is not optimized for low speed turning but can more than hold its own against traditional 4th gen.
If you are gonna complain about bleeding energy then nothing loses energy more than cobra or falling leaf. The point is to demonstrate control authority at high AOA, not for use in combat.
lcloo
Major
Agreed The bold parts points to the design priority of J20. Dog fighting is not a priority for a 5th stealth fighter. J20 is designed to kill the opponent at distance of more than 200km away, it was not designed to enable some stunt not likely be used in actual aerial engagement.
Doing cobra or a flat spin is unneccesary and asking for this ability is in wrong direction.
and what happens when a raptor shows up?
I was saying that I don't think the tumble climb was an intentional maneuver that demonstrates control authority at high AOA, but the study you quoted is interesting, and suggests that maybe it was indeed intentional.
Literally no one talked about dogfighting except you. I hate how whenever the J-20's maneuverability is called out, and rightfully so because it's simply not nearly as maneuverable as the F-22 and Su-57, everyone gets insecure and starts talking about how dogfighting isn't useful anymore to try and defend it. You realize that maneuverability isn't just used in dogfighting right?
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Maneuverability is not just low speed high alpha maneuverability, it also includes high velocity maneuverability for which the J-20 excels at. One circle/two circle fights in traditional air combat does not happen anymore. Important aspects of aerial combat are sensor fusion and first shoot, first kill capabilities. Nose pointing and supersonic maneuverability are more important for those kind of fights.
Has it ever demonstrated its high velocity maneuverability? If we're talking about nose-pointing, then I believe it doesn't have a notable sustained turn rate, nor minimum turning radius, at least compared to the raptor's from what was shown. Hopefully the upcoming changchun airshow proves me wrong.
To clarify, are you asking about what J-20 has demonstrated, or what its actual maneuverability should be?
Others have already explained to you how restrained and conservative the PLA is in displaying the kinematic performance of their aircraft (not just J-20, but also Flankers, and J-10s) at airshows.
If you are hoping for demonstration, then you will need to accept you're never going to see it.
The design paper said there were considerations for dogfighting in the design. That was what was discussed in the decision to go with canards and to go with a risky complex vortex generation system, to maximize lift, aka turning performance, despite expectations of inferior engines.
The SU-27 doesn’t need TVC for some post stall maneuvers. Canards preserve control authority at post stall angles so if the canards are designed for pitch control (aka they have sufficient surface area to steer nose pointing like the J-20 and Eurofighter) they should be able to do post stall maneuvers. Whether that’s optimal is a different question, but in general post stall maneuvers aren’t useful in modern dogfighting. Post stall is a last ditch move and if you don’t land your kill after executing a post stall maneuver you’re basically dead (as the Indian Air Force found out with their Su-30MKIs).
Even if you’re not overanalyzing and these are actual issues in the flight display why does that matter? If a fighter is flying at airshow speed and altitude it’s basically dead anyways.
They both try to preserve and recover energy and dash out of the phone booth to do so because whoever loses energy advantage first will probably lose? Neither are going to choose to do a hard bleeding turn for more than one shot because whoever wastes their potential energy first will be a sitting duck for the other?
You clearly didn’t read the original design paper for the J-20. At least do that much before you “call out” the J-20’s maneuverability. You’re the one being insecure here. Maybe also learn how maneuverability works in real fighter combat. Low energy envelopes are where you go to die, so low speed low altitude performance is actually pretty unimportant?
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