J20 Stealth Fighter

MiG-29SMT

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On J-20 we can see the limitations of copying western design ideas, the wing is too far aft, thus the trailing edge extension of the wing is much less streamlined than on F-22 or F-35 generation more turbulent flow due to thick wing trailing edges extensions


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F-16 has a quiet streamlined rear
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same is F-15
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MiG-29SMT

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Streamlined rear of MiG-29, thin and streamlined tail booms and pancake ideal for podded engine nacelles

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poor aerodynamic design, thick rear wing trailing edge extension, F-22 has better streamlined rear fuselage

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and less abrupt change from intake to rear nozzles
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MiG-29SMT

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J-20 high drag rear wing trailing edge back strakes, compared to the low drag MiG-1.44 aft strake
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pipebomb

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View attachment 133334

Streamlined rear of MiG-29, thin and streamlined tail booms and pancake ideal for podded engine nacelles

View attachment 133335

poor aerodynamic design, thick rear wing trailing edge extension, F-22 has better streamlined rear fuselage

View attachment 133337
and less abrupt change from intake to rear nozzles
View attachment 133338
Come on man, we have to keep in mind that mistakes are part of learning curve afterall its their first clean sheet design attempt. Indian lca have shortfalls in area ruling and we definitely learned from it. IMHO we need to cut them some slacks.
 

MiG-29SMT

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Come on man, we have to keep in mind that mistakes are part of learning curve afterall its their first clean sheet design attempt. Indian lca have shortfalls in area ruling and we definitely learned from it. IMHO we need to cut them some slacks.
correct, but here you have to see the compromises done to get the configuration.

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On X-36 the wing has a higher aspect ratio

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The wing and canard are coplanar for better stealth planform alignment

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Generally several early configurations are always studied each one offers advantages and disadvantages.

J-20 has relatively higher aspect canards than X-35 concepts for lower induced lift-drag, the canards have dihedral for better vortex canard wing interaction.

https://aviationhumor.net/the-joint-strike-fighters-program-history/
 

Super Flanker

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Presented in HD! J-20 Fantastic Technological Extreme Image Released This may be the coolest J-20 blockbuster you have ever seen!

J-20 5th Gen...
 

Super Flanker

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Finally a first clearer image of the J-20 engine testbed - as it seems an older 201x prototype - was posted. Even if still not clear of a TVC-variant of the WS-10C or already the rumoured WS-15, it anyway clearly reveals for the first time the nozzles.

(Image via @shawnhwang_)

#China #PLA #J20
An U/I RCS test site.
Notice the stealthy aircraft model.
 

Super Flanker

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Relax its a 1:1 of F-117 for Radar Spectroscopic Studies. Even Russians and US do that and we also do that.
Could you please elaborate the term "Radar Spectroscopic studies" in more detail?

Because I have searched on Google with regards to this Exact term and have found nothing with regards to it.

What is exactly? Like you study the Radar Cross Section or something?
 

scatterStorm

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Could you please elaborate the term "Radar Spectroscopic studies" in more detail?

Because I have searched on Google with regards to this Exact term and have found nothing with regards to it.

What is exactly? Like you study the Radar Cross Section or something?
Just google Radar Cross Section of J20, F22 etc. You will get it why 1:1 model is required.
 

scatterStorm

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correct, but here you have to see the compromises done to get the configuration.

View attachment 133463

On X-36 the wing has a higher aspect ratio

View attachment 133464

The wing and canard are coplanar for better stealth planform alignment

View attachment 133465

Generally several early configurations are always studied each one offers advantages and disadvantages.

J-20 has relatively higher aspect canards than X-35 concepts for lower induced lift-drag, the canards have dihedral for better vortex canard wing interaction.

https://aviationhumor.net/the-joint-strike-fighters-program-history/
I would like to add that USAF has gone back to the amazing studies conducted on X-36 airframe and high aspect non-vertical rudder or rudderless design for there NGAD 6th gen concepts. The F22 like very low aspect engine nozzles are going to be seen again on NGAD.
 

MiG-29SMT

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I would like to add that USAF has gone back to the amazing studies conducted on X-36 airframe and high aspect non-vertical rudder or rudderless design for there NGAD 6th gen concepts. The F22 like very low aspect engine nozzles are going to be seen again on NGAD.
TVC nozzles have limits, tailess aircraft also are limited. In reality vertical stabilizers will not go away.

As speed increases aircraft need vertical tail, flying wings are mostly subsonic, stealth aircraft can not use a lot thrust vectoring, thrust vectoring nozzles are mostly a post stall feature or a STOL need, at high speeds they can use them but very limited since the vector will go against the main flight path.


On YF-12 consider they eliminated part of the wing LEX /chines and they added 3 vertical tails.

Plus speed increases air friction heating up the airframe.
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on SR-71 they retained the chines and eliminated the ventral fins
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The next generation fighter might have chines
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but a more realistic one will need vertical tails

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MiG-29SMT

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Could you please elaborate the term "Radar Spectroscopic studies" in more detail?

Because I have searched on Google with regards to this Exact term and have found nothing with regards to it.

What is exactly? Like you study the Radar Cross Section or something?
In nature there is a simple rule
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Stealth is mostly propaganda, since matter and energy can not be destroyed, the electromagnetic waves are just scattered to a different direction by the angle of reflection
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Electromagnetic wave energy is either absorbed or reflected

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so to explain it simple, J-20 is detectable and it will depend upon the radar transmitting power the range it is detected
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Each shape has a different scattering pattern a sphere 360 degree, a corner reflector 60 degrees etc etc, however the size of two same shape bodies will have a different amount of energy reflected, for example a larger flat plate will scatter more energy than a smaller flat plate.

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If you look at the light spectrum each element only absorbs a limited amount of energy, they are the black lines that interrupt the color or colors of the light spectrum, in few words RAM is also propaganda, most energy is reflected, very little absorbed.

So to understand stealth is mostly dependant upon how much energy a radar emits, most radars on aircraft are weak, that is the reason stealth works, but the reality is get a more powerful radar it does not matter is PESA or AESA, a very powerful radar will detect stealth aircraft, a system of radars will do it better.
 

Super Flanker

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I think so that is this is a mock-up of the J-20 made by the US. This particular photo has been Taken from a Marine Corps airfield in North Carolina{I don't remember the exact Date though}
~

It's pretty common for the US military to use realistic rival aircraft for training purposes or even for realistic aggressive opposing-forces training.
~
{Here is another photo of the Mock-Up}=
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