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Why jet engines aren't made in China

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Re: Why jet engines aren't made in China

#331

Post by maxglute »

foldr wrote: post #328
maxglute wrote: post #316

Earlier quoted context omitted.

WS15 matches western on raw power, i.e. comparable thrust to f119/f135 (f22/f35). PRC cores lacks CMC which was last (2000s) western hot section revolution, but that's more about efficiency ~10-20% better range. We don't know WS15 maintenance/metallurgical gap - no one really knows if their service/overhaul hours, but even if heresay assumption 30-50% lifepsan, that's something PRC industrial output can circumvent, i…

I think we're talking slightly at cross purposes. The f119 is an engine that flew in 1997. So while the WS-15 is evidence that China can make modern, well-performing military jet engines, it doesn't show that China has caught up with the West in that particular area. For civil applications, fuel efficiency is non-negotiable if China is to sell engines outside its domestic market.

I'm just point out lead in specific area can be made up elsewhere and not indicative of overall lead.

WS15 is basically parity with F135 in terms of trust/kinematics, i.e. PRC is functionally at parity with latest fielded US military engines. US still head in efficiency and (heresy osint) lifespan but those are swap, logistics issues that can be worked around, - 20% fuel efficiency negated by larger airframe to carry more fuel (25% for single engine, 40% for twin) and lifespan by just building a lot of cores. There is something to be said about PRC 4/5 gen are twin/triple engined, i.e. in aggregate, on paper MUCH more trust/perf/power gen than single engine F35 w/F135. And now that PRC MIC aviation is starting to spam airframes, J20 triple digits, J35s about to explode, and we are talking about underlying industrial chain that is on trend to supply 3-4x+ more engines than US per year for airframes (not factoring in spares). Have to view from systems perspective, US engine lead =/= platform lead, and US fundamentally constrain in F35/5th gen fleet as single engine and 6th gen in limited quantities, and tyranny of distance in westpac = 20% efficiency from being 10 years ahead in CMC doesn't give meaningful edge. F35/F135 having 20% more fuel efficiency matters less when J20 bruteforces twin engine by being larger, with ~2x combat radius and ability to carry larger AAs. As long as US not willing to go twin engine with large % of fleet, all the cost/readiness implications, being ahead in particular area of jet engines hard = false sense of security/advantage.

But civil aviation, efficiency at CURRENT high fuel prices is none negotiable. There is cross over point where if fuel prices drop to precedented level lows, PRC can make up TOC of less efficient / lifespan engines on capital side... just having 1/2 cost airframes and maintenance packages can weather efficiency buffer over lifetime. But that is going to be very real struggle.

Re: Why jet engines aren't made in China

#332

Post by nradov »

coderenegade wrote: post #327
nradov wrote: post #306

Earlier quoted context omitted.

LLM based agentic systems can never meet current FAA certification requirements for civil aircraft. The problem is that the internal logic is essentially a black box and there's no way to verify that it won't go off and do something totally bizarre in an unpredictable way. Now you could argue that human pilots are subject to the same limitation, and there have been a few cases where humans have intentionally crashed…

It would depend on what the data says. By the time putting such systems into civil airframes is even a conversation, there will be an enormous amount of data generated by unmanned systems and military vehicles. If the data shows that a given system is acceptable, I don't see any reason it wouldn't be allowed. That's not the same as saying that current architectures are acceptable, because clearly they aren't. But bot…

No, you're missing the point. You can't demonstrate safety regulation compliance with data. The entire avionics software development process has to be structured from the start to allow for validation.

Military experience, especially with unmanned systems, is largely irrelevant. They operate on a different set of rules and are generally willing to accept a higher level of risk in order to accomplish the mission.

Re: Why jet engines aren't made in China

#333

Post by foldr »

maxglute wrote: post #331
foldr wrote: post #328

Earlier quoted context omitted.

I think we're talking slightly at cross purposes. The f119 is an engine that flew in 1997. So while the WS-15 is evidence that China can make modern, well-performing military jet engines, it doesn't show that China has caught up with the West in that particular area. For civil applications, fuel efficiency is non-negotiable if China is to sell engines outside its domestic market.

I'm just point out lead in specific area can be made up elsewhere and not indicative of overall lead. WS15 is basically parity with F135 in terms of trust/kinematics, i.e. PRC is functionally at parity with latest fielded US military engines. US still head in efficiency and (heresy osint) lifespan but those are swap, logistics issues that can be worked around, - 20% fuel efficiency negated by larger airframe to carry…

We don’t really disagree on any substantial point. However, if we’re going by the F135, that’s an engine that first flew in 2006. If China now has an engine that’s comparable to it it some ways, that means it’s about 20 years behind, give or take.

As you say, militarily speaking, engine tech is just one of many factors. Quite possibly, China would beat the US in a real war just in virtue of being able to manufacture more screws.

Re: Why jet engines aren't made in China

#334

Post by hakfoo »

bluegatty wrote: post #184
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…

The free market works fine - the problem is at that scale, we can only afford a few key players, they're strategic so they end up having subsidies other considerations. Put differently: if the population of the earth were 50 Billion people instead of 8 Billion - then we'd have markets with enough competition to allow free market dynamics. In that context, then we'd have 'Space companies' being subsidized. We'd have a…

I'm not sure if a bigger population would really justify more jet manufacturers.

Outside of general aviation (hobbyists/business jets), the potential buyers for jet aircraft are going to trend towards natural oligopoly.

Military craft, there's basically one buyer per country, at most a handful of different decision makers behind the same basic chequebook.

Civilian craft, does the number of airlines scale with population? There are a finite number of viable routes, airport slots, and market segments, so would it actually support a hundred new airlines, or would we just end up with a Big Southwest buying 1,000 737s instead of 100?

Even if you had more airlines, would they want to diversify their fleets? Running the same few types of planes, especially if they're the same types of planes as their competitors, unlocks efficiencies. How much would it cost a random American or European airline to retrain their pilots to fly the Comac C919, and how much would they spend extra on adaptations (stocking new spares, retraining maintenance staff, retooling processes for different floorplans)? I also suspect there's a very strong CYA/risk aversion mindset that would make it very hard to sell a new player into the market.

Regional flag carriers have political excuses to support a buy-local policy at some cost, but that still only justifies a handful of manufacturers per economic hegemon.

Re: Why jet engines aren't made in China

#335

Post by OneDonOne »

dingaling wrote: post #94
OneDonOne wrote: post #33

Earlier quoted context omitted.

It is not the pen, it is the pen tip . Ballpoint pen tips are microscopic tungsten carbide ball held inside ultra-thin steel sockets. So you need cutting tolerances precise to 0.001 millimeters. If the socket is a fraction of a micron too loose, the ink leaks. Too tight, and the pen won't write. Source from al-Arabiya: https://english.alarabiya.net/variety/2017/01/14/At-last-Chi... The point (no pun intended) is that…

The ballpoint pen was invented in 1938. It doesn't rely on any arcane manufacturing technology.

They do. The micro-precision subculture required to (in order):

1. Powder prep your tungsten carbide

2. Form said powder

3. Thermally prepare the resulting slurry using a vacuum forming furnace

4. Finish it with diamond lap grinders, lapping machines and polishing machines

5. Clean it ultrasonically, with solvent, rinse, then dry them.

6. Have the metrology required to test thousands of micron-scale balls a day (a world-beating skill in itself)

7. Build a QA lab that can assure the quality of said balls statistically (you can test them all).

8. And then integrate them via socket assembly

are not just hereditary, but proprietary. And assuming a competitor does manage to achieve the basic ISO 3290 and ASTM F2094 standards, you still need tacit knowledge. Stuff like sintering temperature curves, proper powder grain distribution, polishing chemistry, proper statistical rejection thresholds and a whole lot more.

And that is just the ball. Not the socket, or the ink channels. Making a perfectly spherical 0.5 mm ± 0.0001 mm tungsten carbide ball requires the same techniques used in building micromotors, medical devices, and semiconductor subcomponent manufacturing. Techniques such as high-volume sorting, advanced powder metallurgy, controlled sintering, and precision machines that operate 24-hour shifts without drifting. All operated by modern process engineers who are the spiritual (or actual?) descendants of Swiss watchmakers or the glassmakers of Murano.

Re: Why jet engines aren't made in China

#336

Post by OneDonOne »

margalabargala wrote: post #71
OneDonOne wrote: post #33

Earlier quoted context omitted.

It is not the pen, it is the pen tip . Ballpoint pen tips are microscopic tungsten carbide ball held inside ultra-thin steel sockets. So you need cutting tolerances precise to 0.001 millimeters. If the socket is a fraction of a micron too loose, the ink leaks. Too tight, and the pen won't write. Source from al-Arabiya: https://english.alarabiya.net/variety/2017/01/14/At-last-Chi... The point (no pun intended) is that…

They are not microscopic! I can easily see the balls in the tips of ballpoint pens.

The ball is not microscopic, but the tolerances required to make the ball spherical and fit into the socket are.

Re: Why jet engines aren't made in China

#337

Post by margalabargala »

OneDonOne wrote: post #336
margalabargala wrote: post #71

Earlier quoted context omitted.

They are not microscopic! I can easily see the balls in the tips of ballpoint pens.

The ball is not microscopic, but the tolerances required to make the ball spherical and fit into the socket are.

Exactly, so this sentence is incorrect:

> Ballpoint pen tips are microscopic tungsten carbide ball held inside ultra-thin steel sockets

Re: Why jet engines aren't made in China

#338

Post by OneDonOne »

margalabargala wrote: post #337
OneDonOne wrote: post #336

Earlier quoted context omitted.

The ball is not microscopic, but the tolerances required to make the ball spherical and fit into the socket are.

Exactly, so this sentence is incorrect: > Ballpoint pen tips are microscopic tungsten carbide ball held inside ultra-thin steel sockets

Yes indeed, you are correct. My mistake.

Re: Why jet engines aren't made in China

#339

Post by eth0up »

switchbak wrote: post #276
eth0up wrote: post #51

Earlier quoted context omitted.

I guess I can relax and stop worrying that we're falling behind a bit. But I do wonder what the numbers really are, and just how many engineers we produce compared to China, of course, without qualifying everyone that learned Visual Basic as an engineer, unless, of course, that's where they're actually getting their own numbers from.

I see you're getting downvotes, but my intuition strongly aligns with yours. Many of the top minds/academics in (North) America are from overseas, and most of the time that's India and China. And it's been this way for a long time, and it basically makes sense from a numbers perspective. Note that I say this without a particular bias for or against. So when many of the top minds, publishing most of the top papers in…

Thanks for that, and you directly hit the point that most fear to express. Also, you mention India, which strategically, is probably the one critical nation that without, American stands little chance of keeping pace with China. The tariff nonsense and other blunders, have squandered that opportunity though, with many billions now dedicated to stable cooperation with China and a pivot away from the US. What I think many do not see are the repercussions that have yet to show. Forward looking, I see a bleak future. And as an American patriot, I think we're being outdone, in too many ways. On the abstract, I think if we were to nix all the corruption, (and maybe put nootropics in the water supply), we might have a chance, but competing with a highly disciplined collective-oriented society in 2026 onward, I think is a predictable loss with our current paradigm. But at least we have fighting cages on the white house lawn, nu? Our MMA guys can just beat up the Chinese engineers, and anyone who questions our greatness, I guess.

Re: Why jet engines aren't made in China

#340

Post by m0llusk »

yanhangyhy wrote: post #299
m0llusk wrote: post #270

Earlier quoted context omitted.

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

The Second Avenue subway?
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