J-20s that entered service are using the old WS-10B engines, not the WS-15

China rushed its first advanced stealth fighter jet into service ahead of schedule last year, using stopgap engines, in the face of rising security challenges in the region, the South China Morning Post has learned.

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But that means its capabilities will be severely limited, affecting its manoeuvrability and fuel efficiency as well as its stealthiness at supersonic speeds.

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However, the aircraft was equipped with inferior engines designed for earlier warplanes when it first joined the air force in March last year because “critical problems” with its tailor-made WS-15 engine, exposed by an accident in 2015, had not been fixed, two independent military sources told the Post.

“The WS-15 engine designed for the J-20 exploded during a ground running test in 2015,” one source said, adding that no one was injured in the accident.

“The explosion indicated the WS-15 is not reliable, and so far there is no fundamental solution to overcome such a problem … that’s why the J-20 is using WS-10B engines now.”

The WS-10B is a modified version of the WS-10 Taihang engine, which was designed for the country’s fourth-generation J-10 and J-11 fighters.

The explosion was confirmed by another source close to the military, who said the reasons it happened were complicated, with one being the quality control of its single-crystal turbine blades, the key component for such a powerful turbofan engine.

www.scmp.com...


The reason the Chinese decided to move ahead with the J-20 with the stopgap engines is because of their concerns with the US, Japan, India and South Korea. They feel with the other nations getting the fifth generation fighters (well, maybe not India just yet) in the area, the Chinese needed a fighter with some minimum capabilities. better to get something into service than to have the development drag on forever. Go with an 'A' model and then when the new stuff is ready, a 'B.'

What's interesting is the J-20 was spotted flying with the new engines. They might have had an issue still.

And, yes, the problem with the engines is still supposedly metallurgical in nature.

Whatever the cause, without the new engines, that means the J-20 can't supercruise.

Making high quality jet engines is a complex process, but I guess China will crack their problems by stealing tech and chucking money at the problem.

While I am no jet engine expert, from what I have read over the years the Russians have always struggled to get any parity with Western manufacturers.

Single crystal blades?Ceramic?

originally posted by: Blackfinger
Single crystal blades?Ceramic?

Nickel alloys.

Metals are polycrystalline, have grains. By carefully controlling the cooling of the melt you can control the growth of crystal zones, make single crystal parts.

a reply to: paraphi

The Russians have the engineering prowess to do great things, but none of the manufacturing or money to back them up and actually make any of them happen.

The Chinese, otoh, always struggle when it comes to engineering new ideas and solutions, but they have the money and manufacturing ability to crank out just about anything they can get their hands on the plans for.

It's why I'm sure that the DOD feels relieved any time the Russians and the Chinese have a falling out, as a true (think: England/Germany) alliance between the two would lead more or less to M.I.C. parity with the US very, very quickly.

a reply to: Barnalby

The Chinese, otoh, always struggle when it comes to engineering new ideas and solutions, but they have the money and manufacturing ability to crank out just about anything they can get their hands on the plans for. 

They have plenty of bright engineers. The problem is that a lot of industrial solutions involve a sort of arcane community knowledge gained by decades of trial and error, hit and miss, and even some luck.
It's why it has taken 30 years for them to start production of their Blackhawk clone even after we gave them several in the 80's. Even having the plans and the hardware, they lacked the institutional knowledge base required for production. In the case of jet engines, a lot is based on metallurgy. Even knowing the "recipe" doesn't necessarily get you the ability to produce it.

They're learning quickly, but they also have a ways to go. Same issues as everyone else. Time and money.

It also can work backwards with brain drain. As people retire or move to different fields, some industrial solutions in the US aerospace sector from the 60's has seen that sort of arcana disappear from the industry. We've spent billions of dollars and many years of effort relearning lessons that people forgot we had answers to already because those projects were for a different application which noone thought to research and/or were classified. Ask a patent department for a defense contractor how many times they've applied for a patent after years of in house research only to find a patent application already exists secretly which covers it.

So, just another HotRod with a lame 4 Cylinder under the hood.

See you in the clouds boys.

The Russians and Chinese face the same issues, talent yes but not the backup to actually make production models.

The big difference now is that the Chinese has huge amounts of cash to throw at the problem, the Russians don't.

The simple fact is that the west must not sit back and think we have any sort of lead on them now, all we have is a very small temporary advantage and that could disappear VERY quickly, whilst their 5th Gen designs aren't as polished as ours, look at the time it's taken them to advance.

If they seriously sit down and start collaborating properly then that lead is gone.

a reply to: GrumpyBollocks

As far as engines go, we're on the verge of making several advances that will put us even farther ahead, and will be difficult to go from where they are, to where we're about to be without the intermediate steps.

The saying you have to break some eggs to make a good omelette comes to mind..Exciting times for engine tech.And thats the unclassified stuff

a reply to: Zaphod58

Yes I've heard some VERY interesting whispers from different sources, one old acquaintance who's been with Rolls R&D and SNECMA has been doing many trips over the last few years to the US. He's regarded as one of the best in the field of metamaterials and novel alloys for engine usage, every time I see him he normally picks an engine design and explains how many years behind the bleeding edge it is.

He came back to the UK a few months back and we chatted about the Bloodhound car, 1000mph using an EJ200 and a rocket, his comment "what we had in testing two years ago would make that thing do that speed without the rocket and use less fuel"

As with all people in his industry and mine, vague hints are all that's shared, makes for good chats over coffee though

There is alot of stuff you can milli vanilli, but metallurgy is a tough one. The Chicom turbines are basically copies of Russian ones and those are not the best starting points for sure.

They will get it right eventually

originally posted by: Zaphod58
a reply to: GrumpyBollocks

As far as engines go, we're on the verge of making several advances that will put us even farther ahead, and will be difficult to go from where they are, to where we're about to be without the intermediate steps.

turbine-based combined cycle which will give you the advantage of low speed and hypersonic style ram/scramjets in one engine.

a reply to: FredT

That's one, if they can finally get it to work.

originally posted by: Zaphod58
a reply to: FredT

That's one, if they can finally get it to work.

Ive been behind on my AWST mags and was just picking through the recent developments so they seem optimistic. That would a huge game changer IMHO.

Took Ben King well over a year to get the AeroSpike on the Sr71 right.

Edit my bad..It was Ben Rich..Ex director of Lockheeds Skunk Works..

A new and improved engine designed to make China’s J-20 stealth fighter a world-class combat jet should be ready for mass production by the end of the year, military sources have said.

The WS-15 engine features cutting-edge single-crystal turbine blades and has been in development for several years, but Chinese technicians have struggled to get it into mass production.

However, many of the problems – which largely related to blades overheating at top speeds – have been ironed out in ground tests and trial flights, putting the goal of a consistently high quality product in sight, sources told the South China Morning Post.

www.scmp.com...

Time to start watching and counting turkey feathers on the J-20 photos it seems.

a reply to: anzha
Damn and here I was hoping for Magjets