Chengdu J-20 pictures, analysis and speculation Part I

[dannydale]

I think it's pretty obviously shooped.

What makes you think so?? ???

compare it to the previous picture of that

the side bays are gone

when I did the image analysis before, the serrated edges of the bays are gone in the bottom shots and was replaced by "blocks" and only the center line was left

this is an indication of heavy blurring

I was referring to the crazy blue background color and the white 'matte' edge effects, actually. See attached 500% blowup of the canard area from the first pic. I could reproduce that effect by repainting that weird electric blue over a hazy background sky, then applying a bit of blur and noise filters and saving as jpg.

 

[Trident]

That, and the fact that the background colour is so unnaturally uniform - no gradient toward the horizon at all.

 

[Deino]

Is this new ?? ???

 

[sferrin]

As in a new pshop job?

 

[Steve Pace]

Is this new ?? ???

Two images joined together - notice the vertical line in the center. -SP

 

[Deino]

Oh, come on !

That was not the point and surely I see that these are two pictures.
The question is, where they taken during the preparations for or even the first flight on 11. January or are they new ?

Deino

 

[Steve Pace]

One thousand pardons! -SP

 

[Trident]

New, in that we've not seen them before, or new in the sense that they were not taken during the known, previous outings of the aircraft? Personally, I think its the former: the panels in primer suggest the pictures were taken before the first flight, but I don't remember seeing them earlier.

As far as I can tell, they don't look photoshopped.

 

[SOC]

They should be new old pictures. New in the sense that we haven't seen them yet, and old in that the aircraft still has the taxi-trial engine nozzles fitted and spots of primer.

 

[Deino]

In fact they seem to be "newly" released old pictures ... here are some more:

http://www.top81.cn/top81bbs/thread.php?cid=1&rootid=2900936&id=2900936

Deino

 

[flateric]

blue - F-22A, red - J-20

1). canopy profile from CATIA F-22A drawings compared to Gao Shan color 3-view (unrotated and rotated to match Gao's canopy frame angle)
I somewhat presume that Gao Shan surely had access to much more hi-res photos than we ever saw...
2). the same compared to famous VIP vizit photo (canopy rotated in AutoCAD, ajusted to canopy frame size, unrotated)

PPG should watch their security better...

 

[sferrin]

blue - F-22A, red - J-20

1). canopy profile from CATIA F-22A drawings compared to Gao Shan color 3-view (unrotated and rotated to match Gao's canopy frame angle)
I somewhat presume that Gao Shan surely had access to much more hi-res photos than we ever saw...
2). the same compared to famous VIP vizit photo (canopy rotated in AutoCAD, ajusted to canopy frame size, unrotated)

PPG should watch their security better...

People there should be fired and the company fined within an inch of it's life. This kind of incompetence shouldn't be tolerated.

 

[chuck4]

Even if the chinese didn't arrive at this canopy solution without outside inspiration, they don't exactly need to do a whole lot more espinage than opening copies of "Airforce" magazine. So let's not hyperventilate

 

[sferrin]

Even if the chinese didn't arrive at this canopy solution without outside inspiration, they don't exactly need to do a whole lot more espinage than opening copies of "Airforce" magazine. So let's not hyperventilate

If all it was was the shape I wouldn't care. Go look at the photos out there of it open. Even some of the unique details of the F-22's canopy are copied. In other words they didn't simply eyeball it. Sticking your head in the sand won't change that.

 

[SOC]

Gao Shan color 3-view

Which one is that?

 

[flateric]

So let's not hyperventilate

there was no any sense to precisely copycat exact shape of canopy unless they had ready technology chain description and documentation of one specific Sierracine / PPG Ind. produced transparency for other stealth aircraft
needless to say these items are not subject of Air Force Magazine publications

 

[flateric]

Which one is that?

http://club.china.com/data/thread/1011/2722/43/73/7_1.html

 

[LowObservable]

Agree on the hyperventilation.

If everyone who's been compromised by the Advanced Persistent Threat since the mid-1980s was fired, the defense industry would get awfully quiet.

And even the APT will get you only so far. I think it would be fair to call the F-22 canopy craft-built.

 

[sferrin]

I think it would be fair to call the F-22 canopy craft-built.

Really? Might I suggest a new set of bifocals are in order?

 

[Spring]

Even if the chinese didn't arrive at this canopy solution without outside inspiration, they don't exactly need to do a whole lot more espinage than opening copies of "Airforce" magazine. So let's not hyperventilate

Agree, and IMO all this discussion over the canopy 'copycat' is vague and insubstantial .

Anyway, I just have seen the plane take off, can somebody confirm my impressions that it take off climb was low?, the canards demand was very high as well, I'm impressed for their deflection, is that deflection needed?

BTW, I have seen a device in the rear section of the plane in the dorsal part of the fuselage above and between the engines, seems to be a retractable device, what is that?

 

[Dragon029]

I was under the impression that that was a drogue chute dispenser, but perhaps my eyes were decieving me.

 

[sferrin]

Even if the chinese didn't arrive at this canopy solution without outside inspiration, they don't exactly need to do a whole lot more espinage than opening copies of "Airforce" magazine. So let's not hyperventilate

Agree, and IMO all this discussion over the canopy 'copycat' is vague and insubstantial .

Sounds like you could use a new pair of goggles too.

 

[Deino]

Reportedly from yesterday ... 3 months after the first flight ! ???

 

[sferrin]

What is that, the Loch Ness monster?

 

[Deino]

What is that, the Loch Ness monster?

No ... it's the Yeti !

Now better ... ?? ;D

 

[SOC]

Oh you didn't know? That's the tail-sitter VTOL version ;D

 

[RSF]

What is that, the Loch Ness monster?

No ... it's the Yeti !

Now better ... ?? ;D

Excellent photos Deino, thanks!

Rumor has it that this J-20 is #2002 vs. the first flight serial #2001. It will be interesting if we see the same slow build up of released photos like last time....

 

[Deino]

Reportedly from yesterday

http://www.youtube.com/watch?v=Ra4_ZYoW1lY

Deino

 

[chuck4]

So let's not hyperventilate

there was no any sense to precisely copycat exact shape of canopy unless they had ready technology chain description and documentation of one specific Sierracine / PPG Ind. produced transparency for other stealth aircraft
needless to say these items are not subject of Air Force Magazine publications

The whole point is they must have already perfected a radar reflecting transparency, or else they there is no point to trying to build a stealthy jet with a transparent canopy. Once they have a radar reflecting transparency, the next point is to shape the canopy made from it in a way such that it's radar referring properties match the rest of the plane. Here shape IS everything. Either you think they stole the radar reflecting transparency, a point that, even if true, is no news since the existence of this transparency is already long implied by the the known existence of j-xx program; or you think they stole the shape, which is about a bland a charge as saying they stole the color of the tyres.

 

[sferrin]

So let's not hyperventilate

there was no any sense to precisely copycat exact shape of canopy unless they had ready technology chain description and documentation of one specific Sierracine / PPG Ind. produced transparency for other stealth aircraft
needless to say these items are not subject of Air Force Magazine publications

The whole point is they must have already perfected a radar reflecting transparency, or else they there is no point to trying to build a stealthy jet with a transparent canopy. Once they have a radar reflecting transparency, the next point is to shape the canopy made from it in a way such that it's radar referring properties match the rest of the plane. Here shape IS everything. Either you think they stole the radar reflecting transparency, a point that, even if true, is no news since the existence of this transparency is already long implied by the the known existence of j-xx program; or you think they stole the shape, which is about a bland a charge as saying they stole the color of the tyres.

Might I refer you to post #258.

 

[LowObservable]

Sferrin - The point is that the shape of the canopy or its frame is immaterial. The design could be copied from a photo or multiple photos.

The technology challenge of the F-22 canopy involved processes that made it possible to build such a shape with the correct structural, electromagnetic, thermal and optical qualities. There is no way to tell from photos whether the J-20 canopy meets such specs, or how it does so, or how it is made to do so. To imply that it's the result of espionage or negligence by the contractor is unfounded. You simply can't tell.

So your banging away about "bifocals" is irrelevant, and frankly makes you look foolish. I suggest that you retract.

 

[sferrin]

Sferrin - The point is that the shape of the canopy or its frame is immaterial. The design could be copied from a photo or multiple photos.

The technology challenge of the F-22 canopy involved processes that made it possible to build such a shape with the correct structural, electromagnetic, thermal and optical qualities. There is no way to tell from photos whether the J-20 canopy meets such specs, or how it does so, or how it is made to do so. To imply that it's the result of espionage or negligence by the contractor is unfounded. You simply can't tell.

So your banging away about "bifocals" is irrelevant, and frankly makes you look foolish. I suggest that you retract.

Are you suggesting they slavishly copied details thus far unique to the F-22's canopy simply because they saw them in the pictures, didn't know what they were for, and said to themselves, "well hell, we don't know what that does but it must need it so stick it on"? Seriously? Given the progress they've made in other areas of industrial espionage why do you think it would be such a stretch in this instance? If they can steal the designs for nuclear warheads (given the supposed security surrounding them) I don't see why ripping off a canopy design from the manufacturer is such an impossibility.

 

[quellish]

Are you suggesting they slavishly copied details thus far unique to the F-22's canopy simply because they saw them in the pictures, didn't know what they were for, and said to themselves, "well hell, we don't know what that does but it must need it so stick it on"?

Copying an F-22 canopy designed to counter a specific set of threats is not going to be helpful for an aircraft intended to counter a very different set of threats.

 

[sferrin]

Are you suggesting they slavishly copied details thus far unique to the F-22's canopy simply because they saw them in the pictures, didn't know what they were for, and said to themselves, "well hell, we don't know what that does but it must need it so stick it on"?

Copying an F-22 canopy designed to counter a specific set of threats is not going to be helpful for an aircraft intended to counter a very different set of threats.

I'd be surprised if it were that specific. You'd be changing canopies everytime the other guy came up with something new or you flew against a different threat.

 

[quellish]

I'd be surprised if it were that specific. You'd be changing canopies everytime the other guy came up with something new or you flew against a different threat.

The physics are pretty straightforward, and not very open to interpretation or rhetoric. The F-22 and its canopy are designed to have reduced signatures in bands Red, Blue, White and Purple (these are hypotheticals). The J-20 has features which are optimized for a reduced signature in bands Paisley and Plaid. An F-22 canopy on an aircraft that's Plaid would clash. It would stand out. It would be a big "shoot me" sign. Or at least call the fashion police.

 

[sferrin]

I'd be surprised if it were that specific. You'd be changing canopies everytime the other guy came up with something new or you flew against a different threat.

The physics are pretty straightforward, and not very open to interpretation or rhetoric. The F-22 and its canopy are designed to have reduced signatures in bands Red, Blue, White and Purple (there are hypotheticals). The J-20 has features which are optimized for a reduced signature in bands Paisley and Plaid. An F-22 canopy on an aircraft that's Plaid would clash. It would stand out. It would be a big "shoot me" sign. Or at least call the fashion police.

Yes, the physics are straight forward but the laws of nature are the same for both sides. If the treatment of the F-22's canopy is as specific as you claim they'd have to swap out canopies everytime the threat changed. Clearly that is not the case.

 

[quellish]

Yes, the physics are straight forward but the laws of nature are the same for both sides. If the treatment of the F-22's canopy is as specific as you claim they'd have to swap out canopies everytime the threat changed. Clearly that is not the case.

No. The F-22, and it's canopy, are designed for a specific range of threats, and the frequencies and polarizations those threats use. It is for all practical purposes impossible to design for low observables across every frequency. These are easily understood concepts, grounded in physical law, and well defined in the open literature. For example, an inlet screen designed to be less observable to X-band radars is going to be nice and bright to C-band, even if some X-band frequencies are harmonics of C-band frequencies.

I do not see what is unclear about this. There is nothing about the above that would necessitate a "swap out canopies everytime the threat changed" . That statement is either the result of being very misinformed, or intentionally incendiary. If this is a case of the former, perhaps we should add links to the ARRL Handbook and some form of the radar range equation to the Useful Links section of the forum. The latter is not something I can help with.

But to respond more directly, if the F-22 was facing AEGIS as a threat, yes, they would change the canopy and a lot of other things. Clear enough?

 

[sferrin]

No. The F-22, and it's canopy, are designed for a specific range of threats, and the frequencies and polarizations those threats use. It is for all practical purposes impossible to design for low observables across every frequency.

No kidding.

These are easily understood concepts, grounded in physical law, and well defined in the open literature.

Yes, very easily understood which is I why I'm puzzled that you seem to keep missing it.

For example, an inlet screen designed to be less observable to X-band radars is going to be nice and bright to C-band, even if some X-band frequencies are harmonics of C-band frequencies.

Yep.

I do not see what is unclear about this. There is nothing about the above that would necessitate a "swap out canopies everytime the threat changed" .

You can't have it both ways. You can't be so defined that in only works for specific systems in specific bands yet so broad that you can use the same canopy against all of them.

 

[quellish]

You can't have it both ways. You can't be so defined that in only works for specific systems in specific bands yet so broad that you can use the same canopy against all of them.

Again, I don't see what the problem here is. The F-22 is designed for (hypothetically):
J-band
I-band
E-band
X-band
Hokey Pokey-band

The J-20 is not designed for any of those wavelengths. It only sees those bands as friendly. Instead, it's almost completely designed for signature reduction in:
Pa-band
Kt-(sunshine)-band.

These two sets do not intersect. Signature reduction methods for one of these sets does not work for the other. If you are still saying otherwise, or that an aircraft can only be designed for ONE band still, that is not an issue I can help you with.

 

[sferrin]

You can't have it both ways. You can't be so defined that in only works for specific systems in specific bands yet so broad that you can use the same canopy against all of them.

Again, I don't see what the problem here is. The F-22 is designed for (hypothetically):
J-band
I-band
E-band
X-band
Hokey Pokey-band

The J-20 is not designed for any of those wavelengths. It only sees those bands as friendly. Instead, it's almost completely designed for signature reduction in:
Pa-band
Kt-(sunshine)-band.

These two sets do not intersect. Signature reduction methods for one of these sets does not work for the other. If you are still saying otherwise, or that an aircraft can only be designed for ONE band still, that is not an issue I can help you with.

Actually YOU'RE the one who's been saying that. The idea that the coatings on the F-22's canopy defeat ONLY foreign radars is ludicrous. I hate to burst your bubble but the coatings aren't THAT specific. The well documented fact that US fighters have just as much difficulty tracking the F-22 (you know, because the canopy doesn't show up like a christmas tree on their radars as you claim it should) suggests that reality is more in line with what I've been saying. This is also why China would want to copy the canopy. You can continue to regurgitate words you clearly don't understand but that isn't going to bend reality to your will. Sorry.