Chinese Engine Development

Equation said:

But if a rocket engine fails, you basically have to start over and build another one and do some more testing before launching it again. Jet engine on the other hand can be replaceable with a lot less costly than a rocket engine.

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Not exactly true. Space rockets are expensive to make because there's no demand for volume, so no mass production and economies of scale. Space rockets are not the only kinds of rockets though. A fair comparison is between a rocket and a turbofan with comparable thrust (for example, missiles). In that comparison, the engineering demands for the rocket are far less stringent and complex.

There's a reason why we had rocket powered high mach vehicles long before we had air breathing ones.

"中国航空报》昨日报道，10月14日，中航工业“航空报国金奖”颁奖仪式在上海闵行研发基地举行，中航工业商业发动机公司6名外籍专家荣获该奖。中航工业董事长林左鸣对获奖专家为民用航空发动机事业作出的贡献予以了高度赞扬。据悉，我国C-919国产大客机计划使用CFM国际公司的LEAP-X1C进口发动机。为了让国产飞机用上“中国心”，商发公司也在研制相应的国产型发动机。我国在航展上曾展示民用“长江-1000”发动机模型，该发动机技术水平与LEAP-X1C相当。............."

CJ1000 going well. Plan for introduction to C919 around 2022. Comparable to LEAP.
So for those interested, this is the current level of Chinese commercial jet engine tech relative to the best.

Schumacher said:

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"中国航空报》昨日报道，10月14日，中航工业“航空报国金奖”颁奖仪式在上海闵行研发基地举行，中航工业商业发动机公司6名外籍专家荣获该奖。中航工业董事长林左鸣对获奖专家为民用航空发动机事业作出的贡献予以了高度赞扬。据悉，我国C-919国产大客机计划使用CFM国际公司的LEAP-X1C进口发动机。为了让国产飞机用上“中国心”，商发公司也在研制相应的国产型发动机。我国在航展上曾展示民用“长江-1000”发动机模型，该发动机技术水平与LEAP-X1C相当。............."

CJ1000 going well. Plan for introduction to C919 around 2022. Comparable to LEAP.
So for those interested, this is the current level of Chinese commercial jet engine tech relative to the best.

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Let's not count our eggs before they hatch... let's wait until it is tested and introduced for real on the commercial fleet.

Bltizo said:

Let's not count our eggs before they hatch... let's wait until it is tested and introduced for real on the commercial fleet.

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Sure, nothing is guaranteed but these are plans by smart people and it gives an idea of the gap.
BTW, LEAP-1 too is still testing on A320neo, it's not as if it's already there. And we're already hearing talks of performance misses.

Schumacher said:

Sure, nothing is guaranteed but these are plans by smart people and it gives an idea of the gap.
BTW, LEAP-1 too is still testing on A320neo, it's not as if it's already there. And we're already hearing talks of performance misses.

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Which just goes to show that developing new commercially viable turbofans are difficult.

The article itself says the projected dates for CJ-1000 are "if everything goes smoothly". It's still a useful article to tell us what their planned timescale and technological goal level is, but we should also be realistic about whether they can achieve it.

Bltizo said:

Which just goes to show that developing new commercially viable turbofans are difficult.

The article itself says the projected dates for CJ-1000 are "if everything goes smoothly". It's still a useful article to tell us what their planned timescale and technological goal level is, but we should also be realistic about whether they can achieve it.

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Did I say it's not 'difficult' ?
As for 'realistic', that's their plan & they announced it. That's 'realistic' enough for me.
Is it a guarantee ? Like I said, of course not, if you really want to be pedantic about it.

Schumacher said:

Did I say it's not 'difficult' ?
As for 'realistic', that's their plan & they announced it. That's 'realistic' enough for me.
Is it a guarantee ? Like I said, of course not, if you really want to be pedantic about it.

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Let's put it another way -- saying "CJ-1000 is going well" is probably a bit of optimism which is unwarranted at this stage, and my prior points are there to support that main premise.

edit: also, saying "this is the current level of Chinese engine tech relative to the best" isn't quite accurate either, because even assuming CJ-1000 is as advanced as LEAP 1 and assuming that they get CJ-1000 in service by their projected date, CJ-1000 does not reflect upon the level of advancement for other classes of turbofan engines, especially higher thrust high bypass turbofans, if we are talking civilian. It would be most accurate to say CJ-1000 could reflect the level of aimed advancement relative to other LEAP 1 or CFM-56 thrust class turbofan engines. It's pedantic, yes, but it's also a distinction that is important to make.

Bltizo said:

Let's put it another way -- saying "CJ-1000 is going well" is probably a bit of optimism which is unwarranted at this stage, and my prior points are there to support that main premise.

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{facepalm}....So they set a media event, give out awards, announce the schedule, bring attentions to the project because they want to show it's going 'not well' as opposed to 'well' and they're not happy with it. Great.

Schumacher said:

{facepalm}....So they set a media event, give out awards, announce the schedule, bring attentions to the project because they want to show it's going 'not well' as opposed to 'well' and they're not happy with it. Great.

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*cough* WS-10 *cough*

Schumacher said:

{facepalm}....So they set a media event, give out awards, announce the schedule, bring attentions to the project because they want to show it's going 'not well' as opposed to 'well' and they're not happy with it. Great.

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As a PR event? Of course they'll put out a confident face. They could even believe in their own ability to reach the projected schedule. I'm sure we all hope they will too.

But we also should be realistic and critical, and appreciate that they're still at a somewhat early stage of development and calling the programme as "going well" is probably a little premature, given the challenges China has faced in developing new turbofan engines in the past, and the challenges that even experienced engine companies in the west face.

That is why I said we shouldn't count our chickens before they hatch from their eggs... it's still early days, and "good progress" so early on does not mean as much as we'd hope. Let's wait until they get a prototype flying and then see how the schedule fares.