J-20... The New Generation Fighter III

jackliu said:

Ok, it seems you are stuck on drag = RCS. So how does this work?

Let's say at Mach 1.5, the canard stay flat, but it will generate drag from the air circulation.... so how will this effect stealth? Will the radar beam detect the excessive air around the canard?

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MiG is merely repeating a myth.

Stealth design calls for a conic region in front of the plane in which RCS remains low. For example:


For full aspect stealth, the aft region also has reduced RCS:


You can read more about it . If you want to see what the RCS for an actual plane looks like, has some plots showing the RCS profile of J-20 based on simulations.

In any case, an aircraft does not need to fly directly at a radar to be stealthy. An aircraft with its nose pointing away from a radar source is still stealthy, as long as the radar remains in the conic region. Similarly, the aircraft is still stealthy when flight control surfaces deflecting a few degrees. The effects on RCS will be negligible as long as deflection remains small. Large deflection such as 10° or 20° only occurs when the aircraft is maneuvering, which would mean the aircraft is already seen and any talk about RCS would be pointless.

MiG-29 said:

He says this

All aircraft experience a loss of control effectiveness at supersonic speeds. To generate the same maneuver supersonically as subsonically, the controls must be deflected further.

simple like that, if you want to believe up to you, more deflection higher RCS.

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That particular statement from Paul Metz has nothing to do with RCS. Furthermore, his statement refers to supersonic maneuvering, not cruise where RCS is important. Your claim that deflection of control surfaces cause increase in RCS is based upon a myth.

If correct that 2001 & 2002 are now both at Yanglian ... then this must be an older image or .... ????

(image from: )


Deino

Deino said:

If correct that 2001 & 2002 are now both at Yanglian ... then this must be an older image or .... ????

(image from:

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)
Deino

Click to expand...

But first of all, when or where was it confirmed that 2002 had gone to Yanliang? If it was indeed somewhat confirmed, then when was this current picture taken?

Player99 said:

But first of all, when or where was it confirmed that 2002 had gone to Yanliang? If it was indeed somewhat confirmed, then when was this current picture taken?

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Not sure about a confirmation and I need to correctmy post above, it was taken in May / June.

2003 prototype? It's too hard to tell at this point IMHO.

It just looks like a canopy with a cover over it, it could be any aircraft under there. To present that as evidence of another J20 is just trying too hard.

More J20 prototypes will undoubtably appear in due time. No need to force the issue. All we need to do is be patient.

plawolf said:

It just looks like a canopy with a cover over it, it could be any aircraft under there. To present that as evidence of another J20 is just trying too hard.

More J20 prototypes will undoubtably appear in due time. No need to force the issue. All we need to do is be patient.

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You can see the angular shape of the nose which is consistent of a stealth fighter. I don't think is some cover.

Engineer said:

MiG is merely repeating a myth.

Stealth design calls for a conic region in front of the plane in which RCS remains low. For example:

For full aspect stealth, the aft region also has reduced RCS:

You can read more about it

Please, Log in or Register to view URLs content!

. If you want to see what the RCS for an actual plane looks like,

Please, Log in or Register to view URLs content!

has some plots showing the RCS profile of J-20 based on simulations.

In any case, an aircraft does not need to fly directly at a radar to be stealthy. An aircraft with its nose pointing away from a radar source is still stealthy, as long as the radar remains in the conic region. Similarly, the aircraft is still stealthy when flight control surfaces deflecting a few degrees. The effects on RCS will be negligible as long as deflection remains small. Large deflection such as 10° or 20° only occurs when the aircraft is maneuvering, which would mean the aircraft is already seen and any talk about RCS would be pointless.

Click to expand...

For a more rigorous approach, stealth is not magic, it's just math:



Someone should just plug J-20's shape into MATLAB has see what happens. Everything else is just BS. The equations are simple, just FEM cost money and time. (the professionals at CAC (and probably CIA) has already done so and have reached their conclusions. CAC/PLAAF will not waste money on a non-stealthy stealth fighter, that's all we know)