Shenyang FC-31 / J-31 Fighter Demonstrator

this is absolutely NOT to start a tvc argument again, BUT

as we've all noticed that the engine nozzles don't quite fit snugly into their nacelles on the j-31, and as the vtol f-35b is the only other aircraft in development that has a round engine nozzle that also fits somewhat loosely to a round engine nacelle, could it be that the j-31 is designed to be capable of 3d tvc, or even vtol? i've looked at the pics so long that i've convinced myself???

AssassinsMace said:

If the photographer here is in the same postion this might be an accurate measure. I think the poster in another site where I got this from said 17m-18m?

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It looks as though the J31 is parked much closer to the edge of the concrete and the J20 parked closer to the buildings.
I have looked at the one object I can see, which should be roughly the same size on both planes, the Cockpit canopy.
The one on the J31 picture is about twice the size of that on the J20 which indicates it is far nearer the photographer than the J20.

several meter closer position wont make a real difference for this kind of telephoto lens. it's good that the building behind is of the same proportions in both images.

including several percent of possible errors i would put j31 projected length to between 16,5 and 17,5 meters.

For a carrier that's really the sweetspot size-wise. to get the best out of avionics, enough fuel, yet not take up the whole damn deck. But it certainly isn't a small nor should be a lightweight plane. Non LO plane of previous generations of those dimensions would weigh some 10-12 tons. LO plane today is going to approach 13-14 tons, probably. Could be even more if it has A LOT of radar absorbing material, though that is unlikely as today's fighter design approach seems to confine skin RAM to very short radar bands.

SampanViking said:

It looks as though the J31 is parked much closer to the edge of the concrete and the J20 parked closer to the buildings.
I have looked at the one object I can see, which should be roughly the same size on both planes, the Cockpit canopy.
The one on the J31 picture is about twice the size of that on the J20 which indicates it is far nearer the photographer than the J20.

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Good catch there.

Actually, that would mean the J-31 is nearer to the building and farther away from the camera compared to the J-11B.
Assuming the canopy size of the J-31 aircraft is 15% smaller than the J-11B and using the estimated 17m length, my rough calculation (taking into account the above discrepancy) would be that the size of the J-31 is about 2m longer than the estimated size of 17 m.

Re: this is absolutely NOT to start a tvc argument again, BUT

Subedei said:

as we've all noticed that the engine nozzles don't quite fit snugly into their nacelles on the j-31, and as the vtol f-35b is the only other aircraft in development that has a round engine nozzle that also fits somewhat loosely to a round engine nacelle, could it be that the j-31 is designed to be capable of 3d tvc, or even vtol? i've looked at the pics so long that i've convinced myself???

Click to expand...

31001 would be seriously unbalanced if one of the engines failed in VTOL flight. There is realy no place for a twin engined V/STOL or STOVL, even if you think, which I don't, that there is still a place for single engined fighter aircraft of this kind.

P.S. people are writing about comparison with J-20 while the photograph shows a Flanker.

Re: this is absolutely NOT to start a tvc argument again, BUT

delft said:

There is realy no place for a twin engined V/STOL or STOVL, even if you think, which I don't, that there is still a place for single engined fighter aircraft of this kind.

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so, 3d tvc, then, or is it just that the gap between the engine nozzles and the engine nacelles is due to the smaller diameter of the test engines?

Re: this is absolutely NOT to start a tvc argument again, BUT

delft said:

31001 would be seriously unbalanced if one of the engines failed in VTOL flight. There is realy no place for a twin engined V/STOL or STOVL, even if you think, which I don't, that there is still a place for single engined fighter aircraft of this kind.

P.S. people are writing about comparison with J-20 while the photograph shows a Flanker.

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Well now master delft, two things we agree on?

1.No need for STOVL Fighter Aircraft!

2. That J-20 sure does look like a Flanker.

Right, I saw a J-11B with all its shape and yellow primer and I still ended up typing J-20.

Re: this is absolutely NOT to start a tvc argument again, BUT

Subedei said:

so, 3d tvc, then, or is it just that the gap between the engine nozzles and the engine nacelles is due to the smaller diameter of the test engines?

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I suspect the second, but the first is possible. Perhaps both. The thrust loss due to the use of 3d tvc nozzles is less than with the 2d tvc. But I don't see that this gap is necessary for the 3d tvc.

Re: this is absolutely NOT to start a tvc argument again, BUT

delft said:

I suspect the second, but the first is possible. Perhaps both. The thrust loss due to the use of 3d tvc nozzles is less than with the 2d tvc. But I don't see that this gap is necessary for the 3d tvc.

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Wow! twice in one day, our planets must be lined up.