New single engine stealth fighter by chengdu?

PiSigma · Mar 31, 2017

I forgot to say... J20 started out as a single engine design until the scope changed in the late 2000s. 601 was suppose to design the heavy fighter originally.

The reason scope changed was because it was decided that J10 was viewed as a success and that 611's design tech and engineering is seen as 10 years ahead of 601. Also with a new lightish fighter (J10) already a newer heavy one was thought more important so the project was given to 611 instead. So J20 evolved from the original light single engine 5th gen that 611 already started work on.
It is very possible they can go back to their original design and updating it based on J20 experience. But I don't know anything about a single engine 5th gen plane with them right now (not part of the two major projects I mentioned earlier).

Deino · Mar 31, 2017

PiSigma said:
I forgot to say... J20 started out as a single engine design until the scope changed in the late 2000s. 601 was suppose to design the heavy fighter originally.

The reason scope changed was because it was decided that J10 was viewed as a success and that 611's design tech and engineering is seen as 10 years ahead of 601. Also with a new lightish fighter (J10) already a newer heavy one was thought more important so the project was given to 611 instead. So J20 evolved from the original light single engine 5th gen that 611 already started work on.
It is very possible they can go back to their original design and updating it based on J20 experience. But I don't know anything about a single engine 5th gen plane with them right now (not part of the two major projects I mentioned earlier).

Pardon, but that's the first time I hear of that story. As far as I know the original JXX or whatever it was called in the beginning was always for a heavy , twin-engine type to replace the Su-27/J-11-series.

Or do You have any proof of that ?

PiSigma · Mar 31, 2017

Deino said:
Pardon, but that's the first time I hear of that story. As far as I know the original JXX or whatever it was called in the beginning was always for a heavy , twin-engine type to replace the Su-27/J-11-series.

Or do You have any proof of that ?

I mentioned it years ago ... Like probably around 2005 to 2007 I think. 601 lost the heavy fighter to 611 around then. The idea was 601 got experience with flankers so should be better... But they weren't.

Don't got evidence, all word of mouth from family members that work for 611 (then and now)

jobjed · Mar 31, 2017

Deino said:
Pardon, but that's the first time I hear of that story. As far as I know the original JXX or whatever it was called in the beginning was always for a heavy , twin-engine type to replace the Su-27/J-11-series.

Or do You have any proof of that ?

I think it's pretty reasonable what he said. Even without proof, it sounds very much like what we assume the PLAAF was thinking in the early 2000s.

Also, I don't think pisigma's suggesting the JXX project was about a single-engine 5th-gen fighter, only that 611 was prepared to lose the JXX project to 601 so they started an in-house single-engine design to preempt the loss of the dual-engine project. However, they managed to win the JXX project so they adopted their in-house single-engine design to a dual-engine heavy fighter.

Ironically, it sounds exactly like 601's logic for the FC-31; "Oh, we lost the heavy fighter project, let's preemptively make a light fighter project". Alas, it seems 601 has now lost both the heavy and and light.

Blitzo · Mar 31, 2017

jobjed said:
I think it's pretty reasonable what he said. Even without proof, it sounds very much like what we assume the PLAAF was thinking in the early 2000s.

Also, I don't think pisigma's suggesting the JXX project was about a single-engine 5th-gen fighter, only that 611 was prepared to lose the JXX project to 601 so they started an in-house single-engine design to preempt the loss of the dual-engine project. However, they managed to win the JXX project so they adopted their in-house single-engine design to a dual-engine heavy fighter.

Ironically, it sounds exactly like 601's logic for the FC-31; "Oh, we lost the heavy fighter project, let's preemptively make a light fighter project". Alas, it seems 601 has now lost both the heavy and and light.

I think it's this part which Deino is confused at:

I forgot to say... J20 started out as a single engine design until the scope changed in the late 2000s.

I find it very hard to think that J-20/J-XX began as a single engine design or proposal or requirement from the air force...

PiSigma · Apr 1, 2017

Blitzo is correct..J20 for 611 started out as a single engine plane to see how to improve j10 into a next generation plane, To keep their engineers brainstorming at first and see what they can do with it. All of this was about 1 year before J10's maiden flight, since ej10 designs were finalized by then.

Later it became an official project to develop it further by the air force. Around time J10 came out. Mostly because air force was happy with J10.

But very soon after that, the scope changed to current J20. You might remember this is also around the J11A to transition... Which would explain why air force would want 611 to develop their next heavy fighter instead.

Lethe · Apr 1, 2017

Totoro said:
It is absolutely normal and to be expected that China would be working on a single engined stealth fighter. Something needs to replace all those J10s eventually.

J-10s will need to be replaced eventually, but that does not mean they need to be replaced by a single-engine aircraft. I'm not convinced that China needs anything smaller than J-20 going forward.

PiSigma · Apr 1, 2017

Lethe said:
J-10s will need to be replaced eventually, but that does not mean they need to be replaced by a single-engine aircraft. I'm not convinced that China needs anything smaller than J-20 going forward.

Always need the high-low mix

J20 is pretty big, they will definitely need a smaller plane (5th gen). Might not be single engine, but if a future engine is powerful enough and reliable enough, I don't see why not.

Lethe · Apr 1, 2017

J-20 is a large aircraft, but then aircraft are getting larger and heavier across the board, a trend that was evident even before the shift to internal carriage for VLO purposes, and which seems likely to continue.

I don't think we should assume that the future for PLAAF necessarily resembles either the past, or the paths that are unfolding for other nations, where those paths are the product of specific financial and geopolitical circumstances, program histories, etc.

Richard Santos · Apr 1, 2017

PiSigma said:
Always need the high-low mix

J20 is pretty big, they will definitely need a smaller plane (5th gen). Might not be single engine, but if a future engine is powerful enough and reliable enough, I don't see why not.

Having high low mix use the same engine is an logistic advantage.

New single engine stealth fighter by chengdu?

PiSigma

"the engineer"

Deino

Lieutenant General

PiSigma

"the engineer"

jobjed

Captain

Blitzo

Lieutenant General

PiSigma

"the engineer"

Lethe

Captain

PiSigma

"the engineer"

Lethe

Captain

Richard Santos

Captain