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Why jet engines aren't made in China

aakash.substack.com

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Re: Why jet engines aren't made in China

#291

Post by rurban »

> The F-35’s many operational issues are public because of a Western engineering culture that prioritizes shared learning. China has no equivalent. It has nothing like our annual Pentagon reports.

Well, that's not true. I've worked in engine testing, in all countries, and the Chinese shared more than anyone else. We had a huge wiki, and Chinese shared the most, the Koreans and Japanese the least. It might be that they were the worst in speaking English, but the culture was also much stricter. The only ones who worked by shouting. I've not heard much about much shouting in China, just African-style delays. Which is gone by now for sure

Re: Why jet engines aren't made in China

#292

Post by rbanffy »

londons_explore wrote: post #202
rbanffy wrote: post #180

Earlier quoted context omitted.

> Do you think todays aircraft are not designed with the idea that the engine can fail? Of course they are - but the engines are also designed to be extremely reliable, and that's why you get away with two engines on long flights over water, something previously only available for planes with four engines. > No - in effect building jet-engines (that are commercially viable i.e. fuel and efficeny) is not a easy to dis…

> If you have an electric plane with two motors, a big APU-like turbine charging a battery and powering the motors, you might get away with a cheaper turbine, running in less extreme regimes, and still have a more fuel efficient plane r This works for hybrid cars because the power demand when driving varies widely, as does the output speed. The 'hybrid' bit gets huge gains by always running the engine at optimal rpm+…

> A plane cruises for many hours

This is why short-haul flight will be the first to adopt hybrid propulsion.

Re: Why jet engines aren't made in China

#293

Post by Tor3 »

stephen_g wrote: post #110
ifwinterco wrote: post #78

Earlier quoted context omitted.

If you want to sell commercial jets to anyone who isn’t Chinese, 20Y old engines aren’t good enough because modern engines are slightly more fuel efficient. The difference isn’t huge (I think it’s 10-20% or something), but when fuel is your main cost that’s enough to make older engines undesirable

> The difference isn’t huge (I think it’s 10-20% or something) A 10-20% reduction in fuel burn is actually considered pretty huge...

Indeed, a 10%-20% difference is so much that airliners would sell their grandmother (if they had one) for a leap like that. A 2% improvement is considered significant and is a massive economic incentive, even more so these days for long-haul flights which are now in some cases 50% longer due to conflicts, and at times extreme price hikes for jet fuel.

(This applies a bit less to military engines though, where performance is a more important factor. Fuel efficiency is still important though)

Re: Why jet engines aren't made in China

#294

Post by imtringued »

coverband wrote: post #261
nradov wrote: post #231

Earlier quoted context omitted.

Exactly. Advanced turbine manufacturing is largely a chemistry and metallurgy problem. The Great Leap Forward and Cultural Revolution killed off China's intellectual capital so they had to start from scratch in 1976, and only really got moving in 1992. They've been way behind but will catch up eventually.

According to the article, the skills gained from decades of manufacturing experience and the yield capabilities are more critical than simple chemistry and metallurgy.

Not for jet engines, those are basically all about metallurgy and nothing else.

Re: Why jet engines aren't made in China

#295

Post by bgnn »

shalmanese wrote: post #74

The more parsimonious explanation is that commercial jet engine production is downstream of commercial airbody production and China's currently limited by COMAC's scaling woes. All the money and talent in the world can't replicate real users generating real data that you can use to improve. I'd argue the opposite that jet engines have a market structure that's uniquely terrible for traditional free market societies.…

As an engineer in semiconductors in the Netherlands, I hear from a lot of my friends working at ASML the typical red flags of the rot. They have a very thick middle management layer. Nobody feels like they are working at a high tech company with cutting edge solutions. I believe the customer support roles are very dynamic and satisfying.

Re: Why jet engines aren't made in China

#296

Post by randsorex »

bluegatty wrote: post #198
yourapostasy wrote: post #77

Earlier quoted context omitted.

> ...governments don't know how to mandate good corporate governance... For a very brief moment, under the existential crisis condition of total war in WW2, the US government was somehow able to corral corporate governance towards a semblance of common purpose (survival). As I understand it from historians malfeasance was still widespread, but we arguably maybe got a good enough outcome? This is the corporate equival…

Massive stimulus spending, everyone in the country highly motivated and oriented around a communitarian / natonalist goal. You can see it in ukraine right now - they are making drones in their basements in ways that no other country is. These are hard things to factor into economics just as they are very real. Undoubtedly some competition would help.

Exactly. Nothing motivates and unites a society like the physical death involved in war.

I think if you zoom out on a society, you have to have a war regime and a peace regime.

There are going to be coordinating aspects that a war regime can achieve that a peace regime simply can not because the stakes involved fundamentally can't be the same by definition.

Re: Why jet engines aren't made in China

#297

Post by coderenegade »

rbanffy wrote: post #256
coderenegade wrote: post #206

Earlier quoted context omitted.

Aerospace as a discipline has tried just about every propulsion system under the sun. What you're proposing has already been flight tested on an unmanned vehicle, albeit with many smaller props for a larger effective prop disk than the two you're proposing. This is actually better, because electric motors want to use rpm control, so you need to keep the moment of inertia of the propellers low. The efficiency penalty…

> For a hybrid system to be worth it, you need to claw back more efficiency than you lose in going from mechanical energy to electrical energy, and then back again. For short-haul you spend a lot of time climbing and descending in relation to long flights, so the plane spends less time at the optimum the engines were designed for (cruise), so, if the power unit can be at the peak efficiency throughout the flight, wit…

It's unlikely; the energy density just isn't there, even for a hybrid system. Because of the way flight profiles work, you're still talking about enough battery to provide meaningful power for half a flight, which probably isn't feasible in the near term.

And it's not like the industry has missed this possibility. I've seen papers on systems as exotic as combining high temperature fuel cells (SOFCs, PCFCs) with the Brayton cycle to achieve a hybrid powerplant. The bar for novel propulsion systems in aerospace is extraordinarily high, higher (imo) than it is for automotive. The exception is unmanned systems, which are new enough and varied enough that there's been an explosion of activity, which has been exciting to see.

Re: Why jet engines aren't made in China

#298

Post by roenxi »

js8 wrote: post #209
roenxi wrote: post #138

Earlier quoted context omitted.

> The free market fundamentally doesn't have a good response to this problem, excess capital is taken out of these companies during good times and then they run to governments seeking bailouts during bad times but governments don't know how to mandate good corporate governance. Sounds like the free market hasn't been tried, a key plank of the free market on the supply side is that incompetent managers have to go bank…

So you think U.S. would be better at airplane manufacturing had Boeing gone bankrupt at some point in the past? It's a pretty strong claim and I would like to see some theoretical justification, other than belief in the magical free market. In my country, IIRC, we let Aero Vodochody to crash and be bought by Boeing. We are not better at making airplanes, honestly probably the worst than at any other point in history.

Well, no I think something subtly different. I think if you look at the quality of life in Czechia before and after Aero Vodochody went bankrupt it probably rose, all else equal. And the quality of the corporate governance would have been better than in an alternative. It'd be interesting to check the price and quality of the aircraft that were available for use; those two things probably moved in a helpful direction. That last move isn't guaranteed by basic economics, but it seems quite likely in this case.

Re: Why jet engines aren't made in China

#299

Post by yanhangyhy »

m0llusk wrote: post #270
yanhangyhy wrote: post #75

This is also why China has heavily invested in high-speed rail. Even today, many people who are influenced by persistent misinformation and years of criticism toward China continue to question its high-speed rail system, asking why China doesn’t follow the U.S. model of relying on cars and airplanes instead. But China’s limited ability to rapidly scale commercial aviation means it would have to purchase large numbers…

High speed rail in China is a disaster. Basic safety failings have led to repeated crashes and deaths. Confiscation of property on a massive scale has damaged government credibility. Trillions of dollars worth of investment is not paying off while depreciation does it's work. Prices have been cranked up, large numbers of workers have been fired, and the whole system is still deep in the red. The only solid good comin…

know your Enemy dude

Re: Why jet engines aren't made in China

#300

Post by londons_explore »

rbanffy wrote: post #292
londons_explore wrote: post #202

Earlier quoted context omitted.

> If you have an electric plane with two motors, a big APU-like turbine charging a battery and powering the motors, you might get away with a cheaper turbine, running in less extreme regimes, and still have a more fuel efficient plane r This works for hybrid cars because the power demand when driving varies widely, as does the output speed. The 'hybrid' bit gets huge gains by always running the engine at optimal rpm+…

> A plane cruises for many hours This is why short-haul flight will be the first to adopt hybrid propulsion.

There are already some trials with very short flights - ie. Sub 25 miles.

Used for getting between islands for example

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