I think that this one is just temporarily applied to first J-20s, God knows for what reasons. In future if Chengdu takes care of LO in rear hemisphere J-20 and WS-15 (or whatever will equip it) should receive chevrons and high-temperature LO coatings like F119/F135/Izd.30 nozzles.
Chinese Engine Development
- Thread starter jackbh
- Start date
I use to believe hard facts:
- 2001 has started taxi tests with bare metal nozzle that - suddenly - became silver (while didn't change configuration and external shape at all). So what, did they change engines tested while taxi for new to fly for the first time? Or just painted them over?
- closer look shows that 'chevrons' at the intersection of petals and cowling are not physical objects and just ...plain paint or coating...no panel lines at serrated pattern here, just something sprayed over in zigzag
- soon in course of flight program we started to see paint scrubbed - just in the place where petals move one over other that proves that it's something that is not thick and stable to mechanical forces.
Quickie
Colonel
I'm referring to the petals themselves and NOT the zigzag patterns which are of a different colour, a dull grey.
I've already explained it's not possible to paint over that kind of coating. Just look at the instructions. Too many layers of coating and primers. It can easily crack and peel over.
Coating System
VHT provides a multi-high performance coating system for the ultimate in protection and quality. The system includes surface preparation, primer, paint and clear coat.
Prep SP445 Prep Spray
Prime SP118 FlameProof™ Primer
Coat SPXXX FlameProof™ Color
Finish SP115 FlameProof™ Clear
My issue was with the idea of painting over the USUAL jet engine nozzle. I did already try to make this clear in my previous post.
" I don't believe the petals, the usual type and NOT the heat resistance type I mentioned earlier, can be simply painted over. "
I can imagine that, if the J-20 petals are of the high heat resistance type, they can be sprayed over with a VERY THIN layer of (preferably heat resistance) paint, but I'm more towards the idea that a fine surface layer of the desired material of maybe a few microns thick can be manufactured in the factory for aesthetic reason, or more likely, for functional reason i.e. to reduce the heat signature further.
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MiG-29
Banned Idiot
Thank you
sawtooth patterns are dull grey? i see here real zigzag pattern to the left and imitated with paint to the right - they are not even correlated to width of nozzle panels, readily seen showing through the paint
meanwhile, high-fidelity mockup has pronounced staggered zigzag pattern lines at both places
well, that's exactly what we see, no? it's cracking and peeling over
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Quickie
Colonel
Whatever colour you make it out to be, I'm not interested as I never intended to discuss on it.
I see no cracking or peeling. Just the silver coming off a bit at the aft of the petal.
Look, if you believe the usual engine nozzle petal can simply be painted on, then good for you. You don't have to get everyone to agree with you.
My contention is still the same as that of which I've explained in my previous post. i.e.
I see no cracking or peeling. Just the silver coming off a bit at the aft of the petal.
Look, if you believe the usual engine nozzle petal can simply be painted on, then good for you. You don't have to get everyone to agree with you.
My contention is still the same as that of which I've explained in my previous post. i.e.
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The nozzle is just optimized for the plane to reduce IR and RCS. What the engine is? No idea but it does have exact fuel dump as AL31F... I think it is the chinese approach to add Chinese components which the already mastered. We will not see or know when parts are replaced. I often see the discussion about engine types. These planes have different requirements so you cannot judge from the outside what is in it.
broadsword
Brigadier
PLA's aero-engine development shows good momentum
(People's Daily Online)
08:41, April 08, 2013
"The Y-20 transport aircraft of the Air Force of the Chinese People's Liberation Army (PLA) will eventually be mounted with China's independently-developed engines," Chen Maozhang, expert of Chinese aero engines and academician of the Chinese Academy of Engineering, said in a recent interview.
"The research and manufacture project is currently going very well," Chen added. Chinese engineers and technicians are expected to develop and manufacture a new generation of "Taihang" engines.
In Chen Maozhang's viewpoint, "Taihang" bears landmark significance because it not only marks the transformation of Chinese aero-engine research and development from the turbojet engine to the turbofan engine, but also realizes the progress of Chinese aero-engine from medium thrust to high thrust. With the "Taihang" engines, the engine research and manufacture in related fields will move forward on this basis.
"Taihang" engines are the power units of Chinese military aircraft. The improved "Taihang" engines will be used to drive other major combat equipment of the Navy and the Air Force of the PLA. In the future, the improved thrust-augmented model with high by-pass ratio will be fitted to bombers while the non-thrust model with high by-pass ratio will be used for massive transport aircraft like Y-20 and others.
The gas turbines for ships derived from "Taihang" engines will be used as the main drive for large surface ships like destroyers. According to Zhang Enhe, chief designer of the "Taihang" engines, the "Taihang" has provided supports for China to take a path of independent development of aero engines and to realize the 3rd-generation power unit for China's fighter aircraft. It speeds up the leap forward of PLA's aviation weaponry and armament.
The "Taihang" engine has a thrust-weight ratio of 8, which means it can generate the thrust power 8 times of its own weight, which has reached the world's advanced level. Although the "Taihang" engine still has a large room for improvement when comparing with the U.S. F-119 engine with a thrust-weight ratio of 10, nevertheless, as Chen Maozhang put it, "the research and development of engine is a process of constant improvement. It usually requires more than a decade or even 2-plus decades to complete the process from the finalized design to maturity. The 'Taihang' is moving steadily ahead".
Overseas Edition of People's Daily