Harvey King, born in Taiwan, grew up in US, family rooted in mainland China for centuries.
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Peter Wheeler, Pilot · Author has 239 answers and 786.9k answer views
I want to declare that while I was an Engineering major in college, I know very little about aircraft technology in general. Nor am I an aviation enthusiast. I am just a regular guy who happened to read both Chinese and English and pay attention to this particular topic because jet engine is one of yardstick measure one country’s resourcefulness and resolve. Grew up with Soviet style anti-communist propaganda myself, I have learned to be skeptical and read between the lines, especially from Chinese sources.
First of all, jet engine is HARD.
Secondly, let’s get some terminology straight. When we talk about “jet engine” here, we are talking about large thrust, (i.e. horse power) turbofan engines. In this regard, only a handful of nations are able to make their own jet engine: US, UK, France, Russia, Ukraine and mainland China, barely.
US is ahead of just about everyone. UK’s Rolls Royce kind of falling behind US in recent years. France is struggling to maintaining its self-reliance due to relatively small deployment scale and there are no public information on any new engine development; Soviet Block is in a different league, in a sense that Russian/Ukraine engines may have relatively good performance, but they tend to lagging behind West in terms of fuel consumption and time between overhaul. This may not be an issue in military applications at first glance, but it has long term consequences, as OEMs can’t produce civilian engines to maintain its long term financial viability.
Third, mainland China has been making jet engines for DECADES, start with WP-5 (WP = turbojet, an earlier form of jet engine which is rarely used in aircraft nowadays) in 1956, which is a licensed copy of Soviet VK-1 (1947), which itself a knock-off from Rolls Royce Nene (1944).
Not a bad start.
Then, there was Sino-Soviet split. Communist China lost the hand which spoon fed her.
The one of biggest reason why China is so lagging behind in jet engine is the Culture Revolution, which thousands of scientist / engineers were purged, thus, created a talent gap which China took a generation to pick up.
The talent gap and the politics over ANYTHING, including technical know-how and fundamental facts and sciences, took its toll in all aspect of China’s economy and technology, especially consider that China didn’t have much of an industrial base at first place.
China’s early attempt to design a turbofan engine, WS-6 as an example, was severe effected by the political turmoil, significantly contributed the project’s demise.
By the time China got its sanity back, it’s already in 1970s.
At this time, China got a break. UK decided to license Rolls Royce RB.13, “Spey” engine to China. I can’t find any thing on the net explains what was the political reason behind UK’s decision, nor can I find anything on how much China paid for the deal.
Spey engine was used in UK version of F-4 Phantom. It is one of most successful engine design at the time due to its performance and reliability. China designated it as WS-9 (WS stands for turbofan in Chinese).
China and UK signed the license deal in 1974. Since UK committed to transfer technology, but not manufacturing know-how. By the time China overcome all the technical difficulties associate with manufacturing the jet engine (entrer que l'on appelle la production en série), it was already mid 2003. And, even that, I don’t have any information on how China’s WS-9 comparer avec Rolls Royce’s Spey in terms of trust, fuel consumption, and time-between overhaul, etc.
Yeah, that is how far China was behind.
China has announced many domestic made engines since then, but as far as I know, WS-9 is the only turbofan engine that is manufactured in large quantity and used in large percentage of its application jets (JH-7) so far. The engine itself is hopelessly outdated by now.
China recently (late May 2017) announced that a new domestically made jet engine is used to equip the fifth generation stealth fighter J-20. The domestic designation for the jet engine is WS-15. le origine of this engine is relatively straight forward: China negotiated the design and manufacturing right for the engine designated for defunct Yak-141 VTOL fighter's engine, MNPK Soyuz R-79V-300 en 1995.
Again, take a look at the time between China got the design from Russia (1995) to the announcement of WS-15 used in J-20 (2017). And it is probably just a trial run, not serial production.
WS-15 would be China’s most advanced turbofan engine designated for jet fighter applications.
(Russians refused to give out the vector nozzle (Vertical/Short take off ) part of the engine to Chinese in 1995. Some Chinese sources says that during 1998 Russian financial crises, Russia caved in and licensed the vector nozzle to Chinese)
WS-11 is a small turbofan engine. China obtained the design from Ukraine. It is a Chinese version of Ivchenko AL-25. Due to its limited thrust, the military application is limited to trainer aircraft. Note that Ukraine has become China’s strategic partner in this arena. China has formed join venture with Ukraine (after Ukraine refused to sell Motor Sich) to develop jet engines (details are rare, but it seems that the collaboration is in high bypass ratio engines) and in return, China is helping Ukraine with airplane production, radar, and other technologies.
Then, there is WS-13 (medium trust) and WS-10 (large trust).
Both are being taunted as “domestically designed” and “100% ownership of Intellectual Property.”
WS-13 is designed to replace Russia’s RD-33 engine. While I can’t find any information on rather Russia licensed the design to China, some of Chinese sources implied that China has the design blueprints (RD-33 is authorized to be manufactured in China) and WS-13 is based upon RD-33’s design. Putting things in perspective, RD-33 was originally used on Mig-29 fighter, first ran in 1974!
Why WS-13 can be claimed to be indigenous is beyond me.
Since the WS-13 is designed to be swap replace the RD-33 engine used in FC-1/JF-17, it has similar characteristics in terms of physical size, weight, and trust. Chinese source revealed that while WS-13 has higher maximum thrust and no longer have the infamous black trail smoke associated with RD-33, it takes longer to achieve maximum trust AND Chinese WS-13 requires even shorter time between overhaul than the already dismal RD-33 (compare with, let say, GE’s F404) and shorter life span than RD-33.
Pakistan, the sole user of FC-1/JF-17, so far has rejected the WS-13 in favour of RD-33 despite WS-13 supposedly already in serial production. Pakistan stated that JF-17, being a single-engine jet and backbone of Pakistan’s modern air force, prefer a reliable and proven engine than taking unnecessary risk.
I can’t find much information about the origin of WS-10. From various non-reliable and non-authoritative Chinese sources, it seems that WS-10 used defunct WS-6 project as starting point, took design que from CFM56/F101 and to some extent, AL-31F, and use Russian’s control software as basis to clobber together this beast (since Chinese didn’t manage to steal FADEC source code from the West). Some sources stated that the “core” of WS-10 is more closely based upon CFM56 than any Russian design.
(here is where I really wish I know something about the jet engine… what the hell is “core” mean)
While I know CFM corporation (50/50 join venture between US’s GE and France’s SNECMA) has established engine maintenance facility in China for decades, I sincerely doubt that US/France would give away the design blueprints to Chinese. Did Chinese managed to get some design ideas/ reverse engineered simply from maintaining / overhauling the CFM56? How does technology from CFM56, a civilian jet engine used in Boeing 737, can be applied to military applications? All these questions, I am hoping someone on Quora and/or someone has inside track in China can help me to answer.
WS-10 is designed to swap replace Russia’s AL-31F, used in China’s J-11 (which itself a knock off of Russia’s Su-27) and J-10. Last time I check, WS-10, claimed to entered serial production, is plagued with problems including engine failure and dismal time-between-overhaul of less than 100 hours. China was forced to purchase hundreds of AL-31F from Russia recently as a stop gap measure. As far as I know, as of mid 2017, vast majority of J-11 and its variant (J-15, J-16) and J-10 still uses Russia’s AL-31F engines.
For sake of comparison, AF-31, the Russian engine Chinese so desperately trying to replace, first ran in 1981!
(I am skipping the development of large bypass-ratio engines, i.e. engines for transport/cargo/jetliners ,as it follows similar patterns of development struggles)
It is true that China struggles to produce modern jet engines to fit on its modern jets in large quantity and in a reliable manner,
It is true that even China managed to produce modern jet engines in large quantity and in a reliable manner, almost all the engine’s design are at least 20 years old.
It is also true that China is at least one generation behind US on a good day.
But it is a far cry from “not able to produce jet engines domestically.” Most people are confident that China will able to iron out kinks and be able to produce jet engines in large number reasonably reliably within coming decade.
And having an outdated engine on its own give a huge strategic advantage than not having an engine at all. Sweden’s JAS39 Gripen, otherwise a top-tier lightweight fighter that uses US engine, couldn’t export to many countries simply because some of potential market are either competing with US’ F-16, or that US has security concern and refused allow engine to be used in these nations.
Similar situation in Pakistan. By having WS-13 available for replacement, however flawed WS-13 may be, China removed Russia’s last choke point which Russia could stop the sale of JF-17. Given the choice, Russia would much prefer to sell Mig-29 to Pakistan directly instead of merely selling RD-33 engine alone and collecting royalty fees from RD-33 designs.
Since jet engine is so resource-intensive, it is one of those things which free-market doesn’t exist and all nations uses the power of States to focus its effort in development. It is a testament of a nation’s resolve and organizational skill on top of its technical expertise. From this perspective, China’s achievements, however little as it might be, has been quite amazing.
China probably will surpass France by end of 2020s, as China has multiple engine developments in the pipeline.
Who knows, may be China will become one of high tech engine maker in one day.
Lin Xieyi, Aviation Enthusiast
Mise à jour il y a 36w · L'auteur dispose de réponses 721 et de vues de réponses 7.3m
CGTN4’s “Across China” documentary1 (with English subtitles) recently unveiled an important piece of information that is on everybody’s mind since the first flight of the J-20 stealth fighter in 2011 - those mysterious engines on J-20 prototypes. Those who had argued that the J-20 uses the Russian AL-31F engines are going to be disappointed, for we now know it was acually a pair of domestic Taihang WS-10 (~140 kN A/B thrust) for interim solution in the LRIP aircraft, and the Ermei WS-15 is ready for test run. China had leapfrogged from fielding 3rd-Gen turbofan engine(Taihang WS-10) to Fifth-Gen turbofan engine(Ermei WS-15)
Critical bottlenecks overcame by Chinese turbofan jet engine research :
- The Ermei WS-15 delivers 180kN of A/B thrust , as compared to the P&W F119’s 160kN A/B thrust mounted on the United States’ F-22A Raptor.
- Superalloys used for WS-15 turbine fan blades are formed as a single crystal of titanium alloy, which makes it stronger and reliable when subjected to intense heat of working temperature from 1600 to 1700 degrees celsius, withstanding up to a maximum temperature of 1,900 degrees Celsius(2,200K), and reaches lifespan of 3,000 hours.
- Material used for the WS-15 superalloys achieved a shear modulus of E/20, or 3.3GPa, which is the theoretical ideal for fighter jet turbofan engines.
- All critical components and parts are domestically produced.
The wait is finally over for aviation enthusiasts hoping to see the WS-15 in action. The first test run of the WS-15 mounted on the J-20 might occur pretty soon, probably early next year.
UK’s Rolls Royce, United States’ Pratt&Whitney and General Electric will soon find a new competitor entering the tier-1 turbofan jet engine Market : China’s Shenyang Liming AECC.
Notes de bas de page
Abhishek Ayyagari, Digital marketer software developer athlete swimmer skater avid reader and curious human
Répondu il y a 197w · L'auteur dispose de réponses 94 et de vues de réponses 88.2k
Building a jet engine is one thing which even novices do.The real challenge is to make them stick around for long periods of time it is where the metallurgy of the engine comes in you need to make materials that has long lifetimes and only few countries in the world have mastered it.
The list of those critical parts which are present in the hot end of an engine is small.
Single crystal turbine blades instead of normal DS(Directionally solidified )blades.
TBM(THermal barrier)coatings which are applied to tips of rotors that protect them from high temperatures
These are some of the basic tech which chineese and indians lack which is preventing them in coming up with an reliable jet engine with acceptable lifetime rating.
X. Huang, studied at University of Life
Répondu il y a 72w · L'auteur dispose de réponses 227 et de vues de réponses 352.1k
China was late comer in industrialization, China’s industrialization began in 1950s, went through setbacks, twists and turns, the manufacturing industry is experiencing a development stage. Quality craftsmanship and attention to detail are going to be a long haul until expertise in aircraft engines is built. It's very difficulty for China to leapfrog the few developed economies for best aircraft engines.
Rome wasn't built in a day. Full manufacturing support behind the nations is essential for the success of the major global players Rolls-Royce(UK), Pratt & Whitney(US), General Electric(US), CFM International(France), for example, aerospace manufacturers to find ways to incorporate new and existing metallic materials for better performance. China doesn't have enough technologies in this field.
Another factor is slow return on huge investment. China has made up its mind to boost the domestic aero-engine industry as a state-level major project in a collective effort.
Thés Malcolm, Private pilot with IFR rating.
Répondu il y a 72w · L'auteur dispose de réponses 2.3k et de vues de réponses 2.1m
Jet engines are hard engineering. In a lot of engineering you’re trying to deal with only one thing like high temperatures, high speed, pressure, limits on materials. But in jet engines you’re dealing with all of this and more.
If you get anything wrong, your engine catastrophically disassembles itself in midair (blows up).
And the jets that we’re talking about aren’t small, they’re quite large and generate tremendous amounts of thrust. They need to do this for thousands of hours in a highly reliable way. It’s not easy and it’s a test of your engineering infrastructure from research all the way through manufacturing. Relatively few countries do this all on their own.
Will Simmons, Aerospace engineer
Répondu il y a 124w · L'auteur dispose de réponses 745 et de vues de réponses 1.1m
Aeroengines are very complex, and the margins on performance are very tight - no one will run a profitable airline if they are using engines only a few percent less than the majority of the opposition. This makes it a very difficult market to break into: if you cannot sell many engines, then getting experience and more funds for more R&D is yet more difficult.
That the Chinese have struggled to make new engines, having not had their own aeroengine industry, but made decent reverse-engineered engines for years should not be a massive surprise - just don’t expect it to last forever. Aircraft design and manufacture is moving at great pace in China, and I am sure we will see them making competitive indigenous engines before very long.