Not a fighter.Sad JH7A noises in the distance.
J-20 5th Generation Fighter VII
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Quadruple negative here? Took me a while to figure out!
Not sure if this has been posted before:
Amazing picture.. what is the source? Any chance to have the hi-res version.
Looks like a rendering to me.
SteelBird
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Is it only me that I think China designed aircrafts usually have rather narrow wingspan compared to their western and Russian counterparts (J-8, J-10).Quadruple negative here? Took me a while to figure out!
Not sure if this has been posted before:
Not just narrower wing spans but also longer fuselage. This is to achieve comparable supersonic performance without matching engines.
I don’t think the J10 lacked comparable engines to other single engine fighter of the era. The J20 may lack comparable engines for now, but I doubt it would have been designed around subpar engine.
It seems to me chinese designed aircraft favor low aspect ratio, high leading edge sweep back, near pure delta wings, compared to American and Russian designs that favor higher aspect ration, lower leading edge sweep back, cropped delta wings.
delta wings tend to provide higher fuel capacity, higher instantaneous turn rate, but lower sustained turn rate compared fo otherwise comparable cropped delta.
In air combat terminology, chinese fighters may favor agility over maneuverability,
It seems to me chinese designed aircraft favor low aspect ratio, high leading edge sweep back, near pure delta wings, compared to American and Russian designs that favor higher aspect ration, lower leading edge sweep back, cropped delta wings.
delta wings tend to provide higher fuel capacity, higher instantaneous turn rate, but lower sustained turn rate compared fo otherwise comparable cropped delta.
In air combat terminology, chinese fighters may favor agility over maneuverability,
But it should be noted in this wingspan discussion that the J-8 is heavily based on the Mig-21 and more or less a twin engine Mig-21 with some Mig-23. The only other shorter wingspan fighter is the J-20 and that is partly to try and minimise surface area.
Raises the question (which the right experts surely know well) of why the F-22 and Su-57 both went with huge wings. Does it not have an affect on observability? How could it not in the right angles? Was it all just a compromise between excellent kinematic performance and stealth which the Raptor excels well enough at to not worry about the short moments its giant wings would be spiking RCS? The F-35A and B both have smaller wings. B due to VTOL and C has massive ones because of conventional takeoff from carriers might require that extra lift.
It's probably quite obvious to those experts that the J-20's design is optimised for supersonic flight and agility over maneuverability. The long arm canards, longer length, shorter wingspan, sweep angle, and how far stretched back those vertical stabilisers are for high AOA. Supersonic performance certainly places more emphasis for BVR - improving missile launch and positioning of aircraft. Once it gets close and bleeds energy from turns, it exits its optimal range. Which sort of explains why it doesn't even bother with a gun. It isn't to be used WVR. With low enough RCS and against less than top end adversary aircraft, it can still make use of stealth for longer WVR missiles.
Raises the question (which the right experts surely know well) of why the F-22 and Su-57 both went with huge wings. Does it not have an affect on observability? How could it not in the right angles? Was it all just a compromise between excellent kinematic performance and stealth which the Raptor excels well enough at to not worry about the short moments its giant wings would be spiking RCS? The F-35A and B both have smaller wings. B due to VTOL and C has massive ones because of conventional takeoff from carriers might require that extra lift.
It's probably quite obvious to those experts that the J-20's design is optimised for supersonic flight and agility over maneuverability. The long arm canards, longer length, shorter wingspan, sweep angle, and how far stretched back those vertical stabilisers are for high AOA. Supersonic performance certainly places more emphasis for BVR - improving missile launch and positioning of aircraft. Once it gets close and bleeds energy from turns, it exits its optimal range. Which sort of explains why it doesn't even bother with a gun. It isn't to be used WVR. With low enough RCS and against less than top end adversary aircraft, it can still make use of stealth for longer WVR missiles.
During the transient moments when the RSS spike because the wings aligned with radar, the RCC would spike so much making the wings 50% bigger or smaller would make no practical difference to observability.
Whether the effective lifting area of F-22 and Su-57 are truly much bigger than that of the J-20 may be harder to tell. What is the fuselage lift generated by each of the three aircraft during cruise and high AOA? What is the total lift vs drag of the three aircraft? It could well be that the ratio of lift generated by different parts of the plane is different due to their different layouts.
Whether the effective lifting area of F-22 and Su-57 are truly much bigger than that of the J-20 may be harder to tell. What is the fuselage lift generated by each of the three aircraft during cruise and high AOA? What is the total lift vs drag of the three aircraft? It could well be that the ratio of lift generated by different parts of the plane is different due to their different layouts.
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Ultimately you can’t look at wing area alone. The actual lift is a function of wing area*lift coefficient, the latter of which would need to be experimentally determined because it’s determined by the relationship between the object’s shape and the free stream.
I have a semi-credible rumor implying that J-20 with WS-15 engines is ready to roll out soon. I've shared the post with Deino so he could vouch for its authenticity. Not linking it here directly.
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