J-20 5th Gen Fighter Thread V

[dingyibvs]

A higher wing sweep seems inconsistent with a naval design though. I'm also not certain that coupling distance has changed. Another possibility that might make more sense if there's a wing sweep change, though I think a rather unlikely one, is that there will be a J-20B variant meant for the WS-15 which will have drastic aerodynamic revisions, and that the current J-20 design was always optimized for the AL-31s. That would leave the current J-20 a holdover bastard design however, assuming that one variant couldn't be converted to the other. A third possible option might be that this is in fact not a J-20 but perhaps some kind of interim 6th generation design. Anyways, it would be nice if we could get a better picture...or at least a bigger one...

But adding wing area to the leading edge while keeping the wingspan the same is exactly what the Su-33 did. The trick is to add the additional area mainly to leading edge slats. Granted, I'm not an expert in this area, so perhaps others can correct me. As for the canards, they did not move, the wings extended further up, thus making the coupling closer.

 

[dingyibvs]

I have three theories:

1. a random RCS-experiment on a design loosely resembling the J-20

2. indeed a modified J-20 maybe related to the final engine WS-15.

3. what if this is a RCS model hidden under a tarpaulin and assisted by certain structures to make it look different ?

Deino

1) Why would you park a RCS experiment outside? Those things are usually almost glued down to the lab floor.

2) They designed the bird with WS-15 in mind, can't imagine it requiring such extensive modifications to fit them.

3) A tarp doesn't explain the shortened tails.

To me, it's the naval J-20 (J-25?) until proven otherwise.

 

[Deino]

1) Why would you park a RCS experiment outside? Those things are usually almost glued down to the lab floor.

2) They designed the bird with WS-15 in mind, can't imagine it requiring such extensive modifications to fit them.

3) A tarp doesn't explain the shortened tails.

To me, it's the naval J-20 (J-25?) until proven otherwise.

1. Not too uncommon .. also spotted before and several US-birds were tested outside too.


2. Indeed a good argument, but it was just an attempt to explain.

3. Are these really shorter ? IMO that image is so much blurred, that You can't really see anything but the different wing geometry.

.... concerning a naval design: YES, also an option, but then I would have expected an even wider wing.


Overall it is a very strange model ... maybe the tails are missing ??

 

[Tyloe]

From the image it looks like a single engined version. But, Sean O'Connor (SoC) commented at CDF that the dimensions of this RCS model was almost the same as the J-20 length and width wise. If it were a single engine version in J-10, J-11 type mix I'd expect this RCS model to be smaller but that doesn't appear to be the case. SoC said the actual image is larger than the one we have access to online.

Did he consider the shadow of the building with the aircraft? It could be much smaller than his estimate. With the colour of the bird, it could give a misrepresentation from sat photo.

 

[Totoro]

there's not enough information to conclude anything.

it could be some unused j-20 configuration. so we might be looking at old, test mockup which was hauled out for whatever purposes.

it could be a mockup for research of future, new variant. be it naval variant or strike variant. those variants if indeed exist on paper may or may not ever fly.

it could be mock up for some generic demonstration programme - to validate software simulation, so not something that will ever fly.

it could be a mockup for messing with the foreign intelligence, put outside on purpose.

it could be a prop for a movie, which by some strange coincidence ended up on a RCS range.

or a dozen more reasons that we can't think of right now.

 

[latenlazy]

But adding wing area to the leading edge while keeping the wingspan the same is exactly what the Su-33 did. The trick is to add the additional area mainly to leading edge slats. Granted, I'm not an expert in this area, so perhaps others can correct me. As for the canards, they did not move, the wings extended further up, thus making the coupling closer.

But they didn't change the sweep angle. A higher sweep angle lowers your lift coefficient at low speeds, especially for a delta. I also don't think the wings extended further up, I suspect that's just a really fuzzy image with a poorly distinguished shadow.

1) Why would you park a RCS experiment outside? Those things are usually almost glued down to the lab floor.

2) They designed the bird with WS-15 in mind, can't imagine it requiring such extensive modifications to fit them.

3) A tarp doesn't explain the shortened tails.

To me, it's the naval J-20 (J-25?) until proven otherwise.

1) You need to do outdoor testing too.

2) It may be they're pursuing different aerodynamic optimizations with a more powerful engine. Not the first time China has made aerodynamic changes between versions.

3) Unless the tarp is covering a bigger area than the plane.

EDIT: Looking at Deino's side by side it could be that this is a J-20 that's actually typical, but the photo is just so poor quality we think we're seeing changes that aren't there.

 

[kriss]

Seems the photo is taken from an angle instead of from direct above. The scale could be twisted and all our theory may based on wrong information.

 

[dingyibvs]

Deino's photo clearly enlarges the new J-20 pic. You can see the wings of the new J-20 sticking just over the red lines while the wings of the old J-20 are just short of them. Shrink the new J-20 a bit so the wingspans match, and you can see that it's indeed a bit shorter.

I stand corrected on the outdoor RCS testing question.

If you kinda tilt your head and look at Deino's pic closely, comparing the top and bottom pics, the new J-20's trailing edge seems a bit more swept, no? While it's true that a higher sweep decreases lift, increasing the wing area can also increase lift, as well as a closer coupled canard. Who knows what design trade offs could've happened?

In the end though, I suspect you're right, it's just too blurry of a photo to tell anything for sure.

 

[Hyperwarp]

rough sketch....

 

[Broccoli]

To me it looks like the canards are more swept.