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Faro
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Confirmed: 777X First Flight Delayed Due GE9X Issues

Mon Jun 10, 2019 1:55 pm

https://www.fool.com/investing/2019/06/08/the-revolutionary-boeing-777x-jet-is-running-behin.aspx


Apparently issues with the GE9X stator actuation mechanism which was the object of a re-design recently. First flight slated before the year end instead of end of June, with EIS for late 2020 or possibly 2021.

Anyone have any details?


Faro
Last edited by SQ22 on Tue Jun 25, 2019 3:50 pm, edited 2 times in total.
Reason: Title updated
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airboss787
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:04 pm

That seems like a roughly 6-month delay, while not a lot would probably not make initial customers too thrilled. This is only the beginning, a lot of chances for further delays later on in the testing phase. Good luck to Boeing and GE, rather take more time now sorting out all the issues than rectifying them after EIS.
Last edited by airboss787 on Mon Jun 10, 2019 2:06 pm, edited 2 times in total.
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Faro
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:04 pm

“...including pieces of a variable stator-vane assembly which broke free...”


At 01:50 in the following video news report:

https://youtu.be/R9vwqHKx-QM


Seems rather worrying...


Faro
The chalice not my son
 
StTim
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:09 pm

Another place whereby Boeing will be consuming cash. There will be more frames requiring post build fix to incorporate flight test fixes.
 
planecane
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:10 pm

There is an awful lot of speculation in that article by the author. Things like:

Boeing CEO Dennis Muilenburg recently stated that he still expects the 777X to enter service in 2020. However, even if that does happen, it will probably be much closer to year-end than initially planned


The second sentence is just unsubstantiated speculation by the author. If this turns out to be true and there is a significant delay, there will be many more sources than a single Motley Fool article written by an author who does not specialize in aviation.

As of now, I'd take it with a grain of salt.
 
musman9853
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:12 pm

eh, motley fool isn't very trustworthy. they're a blog mostly, kinda like seeking alpha. i'll wait till we get a more reputable source.
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lightsaber
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:13 pm

The GE9X is the most ambitious engine ever. It is a full generation ahead of anything else. So delays are a risk of that level of technology.

Lightsaber
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FrenchPotatoEye
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:29 pm

lightsaber wrote:
The GE9X is the mist ambitious engine ever. It is a full generation ahead of anything else. So delays are a risk of that level of technology.

Lightsaber


Could you expand on that?

I echo Zekes remarks to be honest. I see nothing substantially new or ground breaking???
 
BoeingGuy
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:36 pm

musman9853 wrote:
eh, motley fool isn't very trustworthy. they're a blog mostly, kinda like seeking alpha. i'll wait till we get a more reputable source.


I have not heard of this first flight delay to the end of the year and I’m involved in the program. I’ll believe it if and when I hear it officially announced.
 
Sooner787
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:45 pm

BoeingGuy wrote:
musman9853 wrote:
eh, motley fool isn't very trustworthy. they're a blog mostly, kinda like seeking alpha. i'll wait till we get a more reputable source.


I have not heard of this first flight delay to the end of the year and I’m involved in the program. I’ll believe it if and when I hear it officially announced.


Why were they doing engine tests on the 1st 779X bird last week?

Were they testing a re-designed engine?
 
Starfuryt
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:47 pm

Boeing could really use some good news right about now. I was looking forward to seeing her fly in the summer, hopefully there is still a chance of that happening.
 
NZ321
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:53 pm

This can hardly be unexpected. Normal for leading edge technology we would all agree no doubt. I would imagine we could see further delays. Based on the record of both Boeing and Airbus recently. So let's please not jump to judge but rather try to understand what it is that is unfolding in this incredible technology!
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ericm2031
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 2:58 pm

Although not good news, every new engine recently has and/or still is having issues...even ones in service. Not the end of the world, GE is good at what they do.
 
 
Sooner787
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 3:30 pm

Sure we'll get a definitive word at Paris next week
 
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lightsaber
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 3:56 pm

FrenchPotatoEye wrote:
lightsaber wrote:
The GE9X is the mist ambitious engine ever. It is a full generation ahead of anything else. So delays are a risk of that level of technology.

Lightsaber


Could you expand on that?

I echo Zekes remarks to be honest. I see nothing substantially new or ground breaking???

1. CMCs, first engine with the tech in commercial service.
2. High Mach # compressor.
3. Enhanced variable cycle tech. For certain the variable turbine cooling of the LEAP. I see actuators being bought for more, but I do not know the specifics.
4. Far more cooling systems than I've ever seen. The turbine clearance control is two generations ahead of anything I've ever seen. In fact, it is was Lefebvre (one of the great chief engineers of engine design) presented in 1995 to graduate students (me), GE, Pratt, and RR. Apparently another grad student listened and made sure this happened. The problem for me is which of my three grad school friends who attended that lecture made it happen. And which of Lefebvre's variable cycle ideas..
5. Low turbine tech. See LEAP-1B and take it a generation forward. Traditionally, I have been a fan of Pratt being the leader here, but GE stole the right Pratt people. See the incredible efficiency bump of the PW1100G with the low turbine enhancement.
6. Fan blade tip Mach number, without a GTF a required tech for installing the low turbine tech. You get one guess why Pratt is so far behind in this tech.
7. Enhanced materials in combustor (less cooling air)
8. Finally imitating Pratt in modeling airflow through the whole engine. Engines are a system and tweaking how air flows from:
a. Low compressor to high, the GE-90 and TrentXWB botched this to the tune of 1 to 1.5% system fuel burn. Hint, the director if Pratt engine development warned of this botch with the PW6000 early in his carrier. I'm quite certain Steve will never allow this to happen again.
b. High compressor to pre-diffuser. GE was always good at this, modern modeling has allowed a nice fuel efficiency increase.
c. High turbine to low turbine. Seriously, compared to Pratt the LEAP and Txwb are amateur hour here. Seriously? Pratt has only been mocking GE and RR on this since Pratt won the F119 vs. F120 clearly on this tech. I only mention military for the clear' this tech is awesome!' timeframe.

But the people who focus on component efficiency do not get how to maximize system efficiency. 'How can the engine burn 2% less fuel by making the low compressor 1/4% less efficient?'. Because that makes the high compressor and pre-diffuser that much more efficient... Sigh...

Then there are a bunch of little technologies GE is just good at such as pre-diffuserss and shorter combustors. Not to mention fans. GE invests more in fan design because they are the least ready for GTFs. Oops.

The Mach numbers in the high compressor still are not at what that one lecture discussed. That is because bearings and seals are not there (see PW1100G issues).

I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

I haven't yet begun to discuss what wing efficiency is enabled by folding wing tips. I could do a wing with 4% better L/D than the A350 wing, but only with the aspect ratio. At least I wouldn't do it without that extension to mitigate the risks. Nor have I discussed Boeing's latest take on electrical subsystems. I'm still scratching my head

I work aerospace R&D. I've been exposed to a lot. If you need an example of when adding weight improves a product, see A330NEO (extended wingspan that is heavy and much heavier engines)

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Mrakula
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 4:28 pm

lightsaber wrote:
FrenchPotatoEye wrote:
lightsaber wrote:
The GE9X is the mist ambitious engine ever. It is a full generation ahead of anything else. So delays are a risk of that level of technology.

Lightsaber


Could you expand on that?

I echo Zekes remarks to be honest. I see nothing substantially new or ground breaking???

1. CMCs, first engine with the tech in commercial service.
2. High Mach # compressor.
3. Enhanced variable cycle tech. For certain the variable turbine cooling of the LEAP. I see actuators being bought for more, but I do not know the specifics.
4. Far more cooling systems than I've ever seen. The turbine clearance control is two generations ahead of anything I've ever seen. In fact, it is was Lefebvre (one of the great chief engineers of engine design) presented in 1995 to graduate students (me), GE, Pratt, and RR. Apparently another grad student listened and made sure this happened. The problem for me is which of my three grad school friends who attended that lecture made it happen. And which of Lefebvre's variable cycle ideas..
5. Low turbine tech. See LEAP-1B and take it a generation forward. Traditionally, I have been a fan of Pratt being the leader here, but GE stole the right Pratt people. See the incredible efficiency bump of the PW1100G with the low turbine enhancement.
6. Fan blade tip Mach number, without a GTF a required tech for installing the low turbine tech. You get one guess why Pratt is so far behind in this tech.
7. Enhanced materials in combustor (less cooling air)
8. Finally imitating Pratt in modeling airflow through the whole engine. Engines are a system and tweaking how air flows from:
a. Low compressor to high, the GE-90 and TrentXWB botched this to the tune of 1 to 1.5% system fuel burn. Hint, the director if Pratt engine development warned of this botch with the PW6000 early in his carrier. I'm quite certain Steve will never allow this to happen again.
b. High compressor to pre-diffuser. GE was always good at this, modern modeling has allowed a nice fuel efficiency increase.
c. High turbine to low turbine. Seriously, compared to Pratt the LEAP and Txwb are amateur hour here. Seriously? Pratt has only been mocking GE and RR on this since Pratt won the F119 vs. F120 clearly on this tech. I only mention military for the clear' this tech is awesome!' timeframe.

But the people who focus on component efficiency do not get how to maximize system efficiency. 'How can the engine burn 2% less fuel by making the low compressor 1/4% less efficient?'. Because that makes the high compressor and pre-diffuser that much more efficient... Sigh...

Then there are a bunch of little technologies GE is just good at such as pre-diffuserss and shorter combustors. Not to mention fans. GE invests more in fan design because they are the least ready for GTFs. Oops.

The Mach numbers in the high compressor still are not at what that one lecture discussed. That is because bearings and seals are not there (see PW1100G issues).

I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

I haven't yet begun to discuss what wing efficiency is enabled by folding wing tips. I could do a wing with 4% better L/D than the A350 wing, but only with the aspect ratio. At least I wouldn't do it without that extension to mitigate the risks. Nor have I discussed Boeing's latest take on electrical subsystems. I'm still scratching my head

I work aerospace R&D. I've been exposed to a lot. If you need an example of when adding weight improves a product, see A330NEO (extended wingspan that is heavy and much heavier engines)

Lightsaber


Wow one should be amazed by such great improvements.

You are working on the engine development
?

Every corporation has his own technology some better then others , some worse.

For example RR is leading engine producer for A330 and it was on 777 before NG was introduced. Trent engine were much simplier then PW and GE engines thank to triple spool technology. Do not need all VBV/VSV systems and turbine cooling while keep efficiency.

I do not how far is TXWB now. Anything you told would not mean nothing. New technology does not mean better always.
 
DenverTed
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 4:42 pm

lightsaber wrote:
FrenchPotatoEye wrote:
lightsaber wrote:
The GE9X is the mist ambitious engine ever. It is a full generation ahead of anything else. So delays are a risk of that level of technology.

Lightsaber


Could you expand on that?

I echo Zekes remarks to be honest. I see nothing substantially new or ground breaking???

1. CMCs, first engine with the tech in commercial service.
2. High Mach # compressor.
3. Enhanced variable cycle tech. For certain the variable turbine cooling of the LEAP. I see actuators being bought for more, but I do not know the specifics.
4. Far more cooling systems than I've ever seen. The turbine clearance control is two generations ahead of anything I've ever seen. In fact, it is was Lefebvre (one of the great chief engineers of engine design) presented in 1995 to graduate students (me), GE, Pratt, and RR. Apparently another grad student listened and made sure this happened. The problem for me is which of my three grad school friends who attended that lecture made it happen. And which of Lefebvre's variable cycle ideas..
5. Low turbine tech. See LEAP-1B and take it a generation forward. Traditionally, I have been a fan of Pratt being the leader here, but GE stole the right Pratt people. See the incredible efficiency bump of the PW1100G with the low turbine enhancement.
6. Fan blade tip Mach number, without a GTF a required tech for installing the low turbine tech. You get one guess why Pratt is so far behind in this tech.
7. Enhanced materials in combustor (less cooling air)
8. Finally imitating Pratt in modeling airflow through the whole engine. Engines are a system and tweaking how air flows from:
a. Low compressor to high, the GE-90 and TrentXWB botched this to the tune of 1 to 1.5% system fuel burn. Hint, the director if Pratt engine development warned of this botch with the PW6000 early in his carrier. I'm quite certain Steve will never allow this to happen again.
b. High compressor to pre-diffuser. GE was always good at this, modern modeling has allowed a nice fuel efficiency increase.
c. High turbine to low turbine. Seriously, compared to Pratt the LEAP and Txwb are amateur hour here. Seriously? Pratt has only been mocking GE and RR on this since Pratt won the F119 vs. F120 clearly on this tech. I only mention military for the clear' this tech is awesome!' timeframe.

But the people who focus on component efficiency do not get how to maximize system efficiency. 'How can the engine burn 2% less fuel by making the low compressor 1/4% less efficient?'. Because that makes the high compressor and pre-diffuser that much more efficient... Sigh...

Then there are a bunch of little technologies GE is just good at such as pre-diffuserss and shorter combustors. Not to mention fans. GE invests more in fan design because they are the least ready for GTFs. Oops.

The Mach numbers in the high compressor still are not at what that one lecture discussed. That is because bearings and seals are not there (see PW1100G issues).

I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

I haven't yet begun to discuss what wing efficiency is enabled by folding wing tips. I could do a wing with 4% better L/D than the A350 wing, but only with the aspect ratio. At least I wouldn't do it without that extension to mitigate the risks. Nor have I discussed Boeing's latest take on electrical subsystems. I'm still scratching my head

I work aerospace R&D. I've been exposed to a lot. If you need an example of when adding weight improves a product, see A330NEO (extended wingspan that is heavy and much heavier engines)

Lightsaber

Yes, but can you expand on that? :)
When do you think the next new engine will EIS on the 787 or A350, to be the next step beyond the GE9x?
 
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lightsaber
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 5:16 pm

Mrakula wrote:
lightsaber wrote:
FrenchPotatoEye wrote:

Could you expand on that?

I echo Zekes remarks to be honest. I see nothing substantially new or ground breaking???

1. CMCs, first engine with the tech in commercial service.
2. High Mach # compressor.
3. Enhanced variable cycle tech. For certain the variable turbine cooling of the LEAP. I see actuators being bought for more, but I do not know the specifics.
4. Far more cooling systems than I've ever seen. The turbine clearance control is two generations ahead of anything I've ever seen. In fact, it is was Lefebvre (one of the great chief engineers of engine design) presented in 1995 to graduate students (me), GE, Pratt, and RR. Apparently another grad student listened and made sure this happened. The problem for me is which of my three grad school friends who attended that lecture made it happen. And which of Lefebvre's variable cycle ideas..
5. Low turbine tech. See LEAP-1B and take it a generation forward. Traditionally, I have been a fan of Pratt being the leader here, but GE stole the right Pratt people. See the incredible efficiency bump of the PW1100G with the low turbine enhancement.
6. Fan blade tip Mach number, without a GTF a required tech for installing the low turbine tech. You get one guess why Pratt is so far behind in this tech.
7. Enhanced materials in combustor (less cooling air)
8. Finally imitating Pratt in modeling airflow through the whole engine. Engines are a system and tweaking how air flows from:
a. Low compressor to high, the GE-90 and TrentXWB botched this to the tune of 1 to 1.5% system fuel burn. Hint, the director if Pratt engine development warned of this botch with the PW6000 early in his carrier. I'm quite certain Steve will never allow this to happen again.
b. High compressor to pre-diffuser. GE was always good at this, modern modeling has allowed a nice fuel efficiency increase.
c. High turbine to low turbine. Seriously, compared to Pratt the LEAP and Txwb are amateur hour here. Seriously? Pratt has only been mocking GE and RR on this since Pratt won the F119 vs. F120 clearly on this tech. I only mention military for the clear' this tech is awesome!' timeframe.

But the people who focus on component efficiency do not get how to maximize system efficiency. 'How can the engine burn 2% less fuel by making the low compressor 1/4% less efficient?'. Because that makes the high compressor and pre-diffuser that much more efficient... Sigh...

Then there are a bunch of little technologies GE is just good at such as pre-diffuserss and shorter combustors. Not to mention fans. GE invests more in fan design because they are the least ready for GTFs. Oops.

The Mach numbers in the high compressor still are not at what that one lecture discussed. That is because bearings and seals are not there (see PW1100G issues).

I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

I haven't yet begun to discuss what wing efficiency is enabled by folding wing tips. I could do a wing with 4% better L/D than the A350 wing, but only with the aspect ratio. At least I wouldn't do it without that extension to mitigate the risks. Nor have I discussed Boeing's latest take on electrical subsystems. I'm still scratching my head

I work aerospace R&D. I've been exposed to a lot. If you need an example of when adding weight improves a product, see A330NEO (extended wingspan that is heavy and much heavier engines)

Lightsaber


Wow one should be amazed by such great improvements.

You are working on the engine development
?

Every corporation has his own technology some better then others , some worse.

For example RR is leading engine producer for A330 and it was on 777 before NG was introduced. Trent engine were much simplier then PW and GE engines thank to triple spool technology. Do not need all VBV/VSV systems and turbine cooling while keep efficiency.

I do not how far is TXWB now. Anything you told would not mean nothing. New technology does not mean better always.

Technology reduces fuel burn. Putting Pratt turbine tech into the TXWB alone would reduce fuel burn.
Pratt's low compressor to high compressor would reduce fuel burn another 2%.

All this stuff was proposed by Whittle (in concept, not detail) to improve fuel efficiency.

The GE9x is, based on my opinion, likely to beat fuel efficiency promise by more than the GE-90-115. Recall how that huge improvement beyond expectation, twice the promised fuel burn reduction, changed the 77W business case. In particular with Boeing beating aerodynamics promises.

The A350 is a great plane. The TXWB is a great engine. I literally haven't seen so many improvements ever thrown into an engine as with the GE9x.

It makes it, by far, the heaviest engine possible because adding stuff adds weight (excluding CC's).

But not improve? If you built a Txwb with GE9x tech, it would burn less fuel than the proposed superfan.

RR simplifies engines to reduce development cost, reduce development time, and reduce overhaul costs. These simplified engines burn more fuel. E.g., GENx vs. T1000. Not enough to stop sales, but there is a cost.

The T700 was the highest tech engine on the A330 and sold best (despite having out of date turbines). It is the overall.

I know RR knows stuff. I personally worked the turbine clearance control on the Pearl and was shocked how elegant (simple, yet efficient) that was. I'm certain that new technology will be on all future RR engines.

But adding more precise turbine control, at some point, requires more sensors and more turbine clearance control loops. I believe the Pearl is the limit of o e valve TCC; at least I couldn't have done as well as the Pearl's system. In fact, use the Pearl system with a 2nd for the next Pearl to further reduce fuel burn 2% to 3%.

I don't understand not needing tech when with it the TXWB would have been unstoppable.

Tech development is only funded if there is a business case. Will investing $300 million in R&D produce an item we can add to engine designs that improves the profit? The extreame case is the GTF. It cost multiple billions of dollars.
Bearings and seals for higher Mach # compressors are an obvious answer that Whittle thought would be solved 40 years ago.

Saying doesn't need tech is saying competition sell more. Then again, I'm in R&D, so I want people to employ me. :bouncy:

As long as fuel is expensive (defined as over $30/bbl), I'm not worried. In fact, there is quite a shortage of people with my skills.

Lightsaber
IM messages to mods on warnings and bans will be ignored and nasty ones will result in a ban.
 
Checklist787
Posts: 157
Joined: Sat Jun 01, 2019 2:37 am

Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 5:33 pm

Mrakula wrote:
lightsaber wrote:
FrenchPotatoEye wrote:

Could you expand on that?

I echo Zekes remarks to be honest. I see nothing substantially new or ground breaking???

1. CMCs, first engine with the tech in commercial service.
2. High Mach # compressor.
3. Enhanced variable cycle tech. For certain the variable turbine cooling of the LEAP. I see actuators being bought for more, but I do not know the specifics.
4. Far more cooling systems than I've ever seen. The turbine clearance control is two generations ahead of anything I've ever seen. In fact, it is was Lefebvre (one of the great chief engineers of engine design) presented in 1995 to graduate students (me), GE, Pratt, and RR. Apparently another grad student listened and made sure this happened. The problem for me is which of my three grad school friends who attended that lecture made it happen. And which of Lefebvre's variable cycle ideas..
5. Low turbine tech. See LEAP-1B and take it a generation forward. Traditionally, I have been a fan of Pratt being the leader here, but GE stole the right Pratt people. See the incredible efficiency bump of the PW1100G with the low turbine enhancement.
6. Fan blade tip Mach number, without a GTF a required tech for installing the low turbine tech. You get one guess why Pratt is so far behind in this tech.
7. Enhanced materials in combustor (less cooling air)
8. Finally imitating Pratt in modeling airflow through the whole engine. Engines are a system and tweaking how air flows from:
a. Low compressor to high, the GE-90 and TrentXWB botched this to the tune of 1 to 1.5% system fuel burn. Hint, the director if Pratt engine development warned of this botch with the PW6000 early in his carrier. I'm quite certain Steve will never allow this to happen again.
b. High compressor to pre-diffuser. GE was always good at this, modern modeling has allowed a nice fuel efficiency increase.
c. High turbine to low turbine. Seriously, compared to Pratt the LEAP and Txwb are amateur hour here. Seriously? Pratt has only been mocking GE and RR on this since Pratt won the F119 vs. F120 clearly on this tech. I only mention military for the clear' this tech is awesome!' timeframe.

But the people who focus on component efficiency do not get how to maximize system efficiency. 'How can the engine burn 2% less fuel by making the low compressor 1/4% less efficient?'. Because that makes the high compressor and pre-diffuser that much more efficient... Sigh...

Then there are a bunch of little technologies GE is just good at such as pre-diffuserss and shorter combustors. Not to mention fans. GE invests more in fan design because they are the least ready for GTFs. Oops.

The Mach numbers in the high compressor still are not at what that one lecture discussed. That is because bearings and seals are not there (see PW1100G issues).

I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

I haven't yet begun to discuss what wing efficiency is enabled by folding wing tips. I could do a wing with 4% better L/D than the A350 wing, but only with the aspect ratio. At least I wouldn't do it without that extension to mitigate the risks. Nor have I discussed Boeing's latest take on electrical subsystems. I'm still scratching my head

I work aerospace R&D. I've been exposed to a lot. If you need an example of when adding weight improves a product, see A330NEO (extended wingspan that is heavy and much heavier engines)

Lightsaber


Wow one should be amazed by such great improvements.

You are working on the engine development
?

Every corporation has his own technology some better then others , some worse.

For example RR is leading engine producer for A330 and it was on 777 before NG was introduced. Trent engine were much simplier then PW and GE engines thank to triple spool technology. Do not need all VBV/VSV systems and turbine cooling while keep efficiency.

I do not how far is TXWB now. Anything you told would not mean nothing. New technology does not mean better always.


False.

1. GE has been present since the first 777-200. What allows you to say this?

2. The architecture three chafts is not better. Many issue of the Trent 1000 /787-10 and frost issue on the Trent 800

3. RR is responsible for the disappearance of Lockheed-1011

https://en.m.wikipedia.org/wiki/Lockheed_L-1011_TriStar


"The L-1011 TriStar's sales were hampered by two years of delays due to developmental and financial problems at Rolls-Royce, the sole manufacturer of the aircraft's engines."
Last edited by Checklist787 on Mon Jun 10, 2019 5:37 pm, edited 2 times in total.
 
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enzo011
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 5:33 pm

BoeingGuy wrote:
I have not heard of this first flight delay to the end of the year and I’m involved in the program. I’ll believe it if and when I hear it officially announced.



I agree it will only be confirmed once it is officially announced from Boeing, I don't however think even if you knew about a delay you would be telling us about it on here. :wink2:
 
BoeingGuy
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 5:36 pm

enzo011 wrote:
BoeingGuy wrote:
I have not heard of this first flight delay to the end of the year and I’m involved in the program. I’ll believe it if and when I hear it officially announced.



I agree it will only be confirmed once it is officially announced from Boeing, I don't however think even if you knew about a delay you would be telling us about it on here. :wink2:


Correct. I wouldn’t have posted anything if I had Proprietary information about a delay. However, as I said I haven’t heard or seen anything about it. Doesn’t mean it is or isn’t true, but hasn’t been announced.
 
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lightsaber
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 5:44 pm

DenverTed wrote:
lightsaber wrote:
FrenchPotatoEye wrote:

Could you expand on that?

I echo Zekes remarks to be honest. I see nothing substantially new or ground breaking???

1. CMCs, first engine with the tech in commercial service.
2. High Mach # compressor.
3. Enhanced variable cycle tech. For certain the variable turbine cooling of the LEAP. I see actuators being bought for more, but I do not know the specifics.
4. Far more cooling systems than I've ever seen. The turbine clearance control is two generations ahead of anything I've ever seen. In fact, it is was Lefebvre (one of the great chief engineers of engine design) presented in 1995 to graduate students (me), GE, Pratt, and RR. Apparently another grad student listened and made sure this happened. The problem for me is which of my three grad school friends who attended that lecture made it happen. And which of Lefebvre's variable cycle ideas..
5. Low turbine tech. See LEAP-1B and take it a generation forward. Traditionally, I have been a fan of Pratt being the leader here, but GE stole the right Pratt people. See the incredible efficiency bump of the PW1100G with the low turbine enhancement.
6. Fan blade tip Mach number, without a GTF a required tech for installing the low turbine tech. You get one guess why Pratt is so far behind in this tech.
7. Enhanced materials in combustor (less cooling air)
8. Finally imitating Pratt in modeling airflow through the whole engine. Engines are a system and tweaking how air flows from:
a. Low compressor to high, the GE-90 and TrentXWB botched this to the tune of 1 to 1.5% system fuel burn. Hint, the director if Pratt engine development warned of this botch with the PW6000 early in his carrier. I'm quite certain Steve will never allow this to happen again.
b. High compressor to pre-diffuser. GE was always good at this, modern modeling has allowed a nice fuel efficiency increase.
c. High turbine to low turbine. Seriously, compared to Pratt the LEAP and Txwb are amateur hour here. Seriously? Pratt has only been mocking GE and RR on this since Pratt won the F119 vs. F120 clearly on this tech. I only mention military for the clear' this tech is awesome!' timeframe.

But the people who focus on component efficiency do not get how to maximize system efficiency. 'How can the engine burn 2% less fuel by making the low compressor 1/4% less efficient?'. Because that makes the high compressor and pre-diffuser that much more efficient... Sigh...

Then there are a bunch of little technologies GE is just good at such as pre-diffuserss and shorter combustors. Not to mention fans. GE invests more in fan design because they are the least ready for GTFs. Oops.

The Mach numbers in the high compressor still are not at what that one lecture discussed. That is because bearings and seals are not there (see PW1100G issues).

I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

I haven't yet begun to discuss what wing efficiency is enabled by folding wing tips. I could do a wing with 4% better L/D than the A350 wing, but only with the aspect ratio. At least I wouldn't do it without that extension to mitigate the risks. Nor have I discussed Boeing's latest take on electrical subsystems. I'm still scratching my head

I work aerospace R&D. I've been exposed to a lot. If you need an example of when adding weight improves a product, see A330NEO (extended wingspan that is heavy and much heavier engines)

Lightsaber

Yes, but can you expand on that? :)
When do you think the next new engine will EIS on the 787 or A350, to be the next step beyond the GE9x?

GE at this time, thanks to CMCs can just retrofit. While at it, design a new casing for the LEAP variable cycle tech to cheaply cut fuel burn other 3%. Then might as well update the low turbine and fan, because that isn't being done now as it requires a new casing.

The next step is obvious:
1. GTF version of GE9x.
2. Keep improving bearings and seals for adding back in contra rotation. Oh, need to increase RPM another third for optimal Mach #.
3. CMCs on the 2nd stage of the high turbine (retrofitable with 90% of the benefit).
4. Develop a material (likely a high density CMC) for the first stage of the high turbine. Who knows when this unobtanium that will drop full burn 4% or more will be invented. Whittle, who really thought this out, thought by the 1980s.
5. Add Pratt's variable fan nozzle. Could it be in the GE8x, I just don't know.
6. Add in variable compressor purge. This is only needed at takeoff until above bird heights. This is another obvious variable cycle technology that someone needs to invent to save about 2% in fuel burn.


Then there is other stuff I need to make sure I'm not under NDA. Technology is maturing, so progress is slowing, but there is much to do before the transition to fuel cells generating electricity powering superconducting motors driving variable pitch ducted fans on a BWB.

Os, Airbus has the best small (250 seat) BWB concept I've ever seen! I personally think Boeing will have to partner with who they did on the 747 again for a BWB.

The airframes are about to undergo a design revolution with next generation CFRP weaving and far larger 3D printing. Alas, from when R&D is ready to EIS is about 22 years. We work to much lower TRL levels. But 3D printing is changing all the rules...

Concept presentation to assembled prototype the next week gets management attention.

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zeke
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 5:47 pm

lightsaber wrote:
[
1. CMCs, first engine with the tech in commercial service.


Nope, not by a long way. CMC parts were EASA certified for service on the CFM56 in 2015, the turbine shroud on the LEAP is also CMC. 3D printed parts from CMCs were used in the Advance3. Advance3 technology is used in the Trent 1000 TEN and the Trent XWB 84 EP. I haven’t heard what P&W is doing, however CMC, CFRP, and 3D printed parts are being used by all 3 big aero engine manufacturers.

“This is the first time in the world that a CMC part has flown on a jetliner in commercial service. ”

Please,see, “A320 Jetliner Starts Commercial Flights With Safran-Designed Ceramic Matrix Composite Exhaust Cone – A World First!”

http://www.defense-aerospace.com/articl ... -cone.html
Last edited by zeke on Mon Jun 10, 2019 6:12 pm, edited 2 times in total.
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remcor
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 5:47 pm

lightsaber wrote:
FrenchPotatoEye wrote:
lightsaber wrote:
The GE9X is the mist ambitious engine ever. It is a full generation ahead of anything else. So delays are a risk of that level of technology.

Lightsaber


Could you expand on that?

I echo Zekes remarks to be honest. I see nothing substantially new or ground breaking???


I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

Lightsaber


That's not mocking. He wasn't mocking you, he was reasonably polite about it as far as the internet goes.
 
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ikolkyo
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 5:52 pm

zeke wrote:
lightsaber wrote:
[
1. CMCs, first engine with the tech in commercial service.


Nope, not by a long way. CMC parts were EASA certified for service on the CFM56 in 2015, the turbine shroud on the LEAP is also CMC. 3D printed parts from CMCs were used in the Advance3. Advance3 technology is used in the Trent 1000 TEN and the Trent XWB 84 EP. I haven’t heard what P&W is doing, however CMC, CFRP, and 3D printed parts are being used by all 3 big aero engine manufacturers.

I’m pretty sure he is referring to major parts like the HPT
that are completely CMC.

What about the rest of his points?
 
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lightsaber
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 6:09 pm

ikolkyo wrote:
zeke wrote:
lightsaber wrote:
[
1. CMCs, first engine with the tech in commercial service.


Nope, not by a long way. CMC parts were EASA certified for service on the CFM56 in 2015, the turbine shroud on the LEAP is also CMC. 3D printed parts from CMCs were used in the Advance3. Advance3 technology is used in the Trent 1000 TEN and the Trent XWB 84 EP. I haven’t heard what P&W is doing, however CMC, CFRP, and 3D printed parts are being used by all 3 big aero engine manufacturers.

I’m pretty sure he is referring to major parts like the HPT
that are completely CMC.

What about the rest of his points?

I'm aware of little parts like swirl guide vanes. Those do not save fuel, it is for pollution reduction and extended life.

I'd like a link. The CMC combustor liners I'm aware of were pulled from duty due to cracking.

The turbine inlet guide vanes is the first major fuel burn reduction part I an aware of.

Yes, everyone does everything. It is what is certification in service.

In my opinion the GE9x is a full generation ahead of the TXWB. I listed why. If I missed an in service or soon to be in service component or subsystem, educate me.

I know quite a bit about the TXWB. It is a great engine. But there is a reason RR is already discussing the Superfan.

There will not be one aircraft to rule then all. The 77W certainly didn't stop A330 sales. The 779, 787-10, and NMA won't stop A350 sales by any stretch of the imagination.

What I haven't discussed is how all this added weight to the 777x to make it extra efficient on long missions (engines, wing folding, more efficient but heavier subsystems) results in a poorly optimizes plane for shorter missions. Meh...

Aircraft need PIPs to keep selling for a reason.

Lightsaber
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Mrakula
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 6:10 pm

Checklist787 wrote:
Mrakula wrote:
lightsaber wrote:
1. CMCs, first engine with the tech in commercial service.
2. High Mach # compressor.
3. Enhanced variable cycle tech. For certain the variable turbine cooling of the LEAP. I see actuators being bought for more, but I do not know the specifics.
4. Far more cooling systems than I've ever seen. The turbine clearance control is two generations ahead of anything I've ever seen. In fact, it is was Lefebvre (one of the great chief engineers of engine design) presented in 1995 to graduate students (me), GE, Pratt, and RR. Apparently another grad student listened and made sure this happened. The problem for me is which of my three grad school friends who attended that lecture made it happen. And which of Lefebvre's variable cycle ideas..
5. Low turbine tech. See LEAP-1B and take it a generation forward. Traditionally, I have been a fan of Pratt being the leader here, but GE stole the right Pratt people. See the incredible efficiency bump of the PW1100G with the low turbine enhancement.
6. Fan blade tip Mach number, without a GTF a required tech for installing the low turbine tech. You get one guess why Pratt is so far behind in this tech.
7. Enhanced materials in combustor (less cooling air)
8. Finally imitating Pratt in modeling airflow through the whole engine. Engines are a system and tweaking how air flows from:
a. Low compressor to high, the GE-90 and TrentXWB botched this to the tune of 1 to 1.5% system fuel burn. Hint, the director if Pratt engine development warned of this botch with the PW6000 early in his carrier. I'm quite certain Steve will never allow this to happen again.
b. High compressor to pre-diffuser. GE was always good at this, modern modeling has allowed a nice fuel efficiency increase.
c. High turbine to low turbine. Seriously, compared to Pratt the LEAP and Txwb are amateur hour here. Seriously? Pratt has only been mocking GE and RR on this since Pratt won the F119 vs. F120 clearly on this tech. I only mention military for the clear' this tech is awesome!' timeframe.

But the people who focus on component efficiency do not get how to maximize system efficiency. 'How can the engine burn 2% less fuel by making the low compressor 1/4% less efficient?'. Because that makes the high compressor and pre-diffuser that much more efficient... Sigh...

Then there are a bunch of little technologies GE is just good at such as pre-diffuserss and shorter combustors. Not to mention fans. GE invests more in fan design because they are the least ready for GTFs. Oops.

The Mach numbers in the high compressor still are not at what that one lecture discussed. That is because bearings and seals are not there (see PW1100G issues).

I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

I haven't yet begun to discuss what wing efficiency is enabled by folding wing tips. I could do a wing with 4% better L/D than the A350 wing, but only with the aspect ratio. At least I wouldn't do it without that extension to mitigate the risks. Nor have I discussed Boeing's latest take on electrical subsystems. I'm still scratching my head

I work aerospace R&D. I've been exposed to a lot. If you need an example of when adding weight improves a product, see A330NEO (extended wingspan that is heavy and much heavier engines)

Lightsaber


Wow one should be amazed by such great improvements.

You are working on the engine development
?

Every corporation has his own technology some better then others , some worse.

For example RR is leading engine producer for A330 and it was on 777 before NG was introduced. Trent engine were much simplier then PW and GE engines thank to triple spool technology. Do not need all VBV/VSV systems and turbine cooling while keep efficiency.

I do not how far is TXWB now. Anything you told would not mean nothing. New technology does not mean better always.


False.

1. GE has been present since the first 777-200. What allows you to say this?

2. The architecture three chafts is not better. Many issue of the Trent 1000 /787-10 and frost issue on the Trent 800

3. RR is responsible for the disappearance of Lockheed-1011

https://en.m.wikipedia.org/wiki/Lockheed_L-1011_TriStar


"The L-1011 TriStar's sales were hampered by two years of delays due to developmental and financial problems at Rolls-Royce, the sole manufacturer of the aircraft's engines."


1. GE was there, I did not denied it, but RR has 44% market share on 772/77E/773! That is what I said.

2. Otger manufacturers have their own issues also
 
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zeke
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 6:40 pm

ikolkyo wrote:
I’m pretty sure he is referring to major parts like the HPT
that are completely CMC.re

What about the rest of his points?


No they have made repeated false claims on multiple threads like the GE9X is the first to feature CMCs. Am aware 5 areas in the GE9X is seeing CMCs beings used, but it is not the first engine to use it in commercial service.

Every company has a different risk appetite. Pratt seem only to have the appetite for CMCs on rotating parts at this stage, RR on static parts, and GE on both. As they all get more experience, and as the software tools, and manufacturing techniques get developed, the proliferation will expand. It is disingenuous to suggest (“CMCs, first engine with the tech in commercial service.”) that only GE and only the GE9X is using them.

I know Airbus has test flown CMCs on A320, A340-300, A350, and A380, I think these test flights go back to 2010. That means the R&D goes back way further.

Same with the claims about cooling in the GE9X, it is an active area of development all manufacturers are using, eg the cooling on Trent XWB 97 is very different to the Trent XWB 84.

Sorry to disagree with their tiny world (GE, US centric) view on aero engine development.

That being said, I cannot think of a single aero engine which didn’t need modification as a result of testing. That’s what the testing is for so it doesn't happen with Joe Public paying for the ride.
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mham001
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 6:56 pm

zeke wrote:

No they have made repeated false claims on multiple threads like the GE9X is the first to feature CMCs. Am aware 5 areas in the GE9X is seeing CMCs beings used, but it is not the first engine to use it in commercial service.

Every company has a different risk appetite. Pratt seem only to have the appetite for CMCs on rotating parts at this stage, RR on static parts, and GE on both. As they all get more experience, and as the software tools, and manufacturing techniques get developed, the proliferation will expand. It is disingenuous to suggest (“CMCs, first engine with the tech in commercial service.”) that only GE and only the GE9X is using them.

I know Airbus has test flown CMCs on A320, A340-300, A350, and A380, I think these test flights go back to 2010. That means the R&D goes back way further.

Same with the claims about cooling in the GE9X, it is an active area of development all manufacturers are using, eg the cooling on Trent XWB 97 is very different to the Trent XWB 84.

Sorry to disagree with their tiny world (GE, US centric) view on aero engine development.


I see a lot of hot air pontificating about that one point. What about the rest of his points? Inconsequential vs those already in service? BTW, where is Pratt based?
 
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keesje
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Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 7:03 pm

Dennis Muilenburg send out a pre-warning last week.

“I don't see anything there right now that would significantly alter the timeline for the 777X, but it's possible we could see something that would alter the content of the test program or how we go about certification”.

“The other pacing item for us is with GE on the engine and we're continuing to work through engine testing and those two timelines will come together for flight testing later this year and then we still expect to achieve entry into service in 2020,”

https://www.google.com/amp/s/www.aerotime.aero/aerotime.team/22693-boeing-ceo-says-777x-not-yet-affected-by-737-max-crisis%3fv=amp

The engine issue would be confirmed now, the possible certification process changes resulting from 737MAX investigations could be solved maybe in paralel.
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 7:23 pm

zeke wrote:
ikolkyo wrote:
I’m pretty sure he is referring to major parts like the HPT
that are completely CMC.re

What about the rest of his points?


No they have made repeated false claims on multiple threads like the GE9X is the first to feature CMCs. Am aware 5 areas in the GE9X is seeing CMCs beings used, but it is not the first engine to use it in commercial service.

Every company has a different risk appetite. Pratt seem only to have the appetite for CMCs on rotating parts at this stage, RR on static parts, and GE on both. As they all get more experience, and as the software tools, and manufacturing techniques get developed, the proliferation will expand. It is disingenuous to suggest (“CMCs, first engine with the tech in commercial service.”) that only GE and only the GE9X is using them.

I know Airbus has test flown CMCs on A320, A340-300, A350, and A380, I think these test flights go back to 2010. That means the R&D goes back way further.

Same with the claims about cooling in the GE9X, it is an active area of development all manufacturers are using, eg the cooling on Trent XWB 97 is very different to the Trent XWB 84.

Sorry to disagree with their tiny world (GE, US centric) view on aero engine development.

That being said, I cannot think of a single aero engine which didn’t need modification as a result of testing. That’s what the testing is for so it doesn't happen with Joe Public paying for the ride.

Ok, I'll update first major use if CMCs in the turbine. Yes, CMCs as coatings have been forever.

But what parts, other than ciatings or guide swirlers?

It happens the turbine CMCs are a milestone the industry has been waiting for 35 years.

That is a major leap forward.

In my opinion the GE8x is one generation ahead. The turbine parts will save.

I'm not being US centric, I am focusing on the GE9x.

There are few new engines that impress me. The GE9x is one. Only a few engines have dramatically altered the competitive landscape:
1. JT8D
2. CF-34 (first 'high bypass')
3. JT9D
4. BMR-7xx (owned high end business jets forever)
4. T700. Finally what the triple spool was capable if.
5. GE-90
6. GTF/LEAP

To my knowledge, the GE-9x is the first to use CMCs to reduce fuel burn (other than as another glad it of thermal barrier coating).

Please provide a link before accusing me if falsehood.

RR has great tech, how many times do I have to credit the greatest gas turbine engineer, Whittle (from UK)?

I personally believe the GE9x is what will make the 777x sell. Just as I believe the T500 killed the A346 (I was working the alternative bid, so I'm biased).

I am also very enthusiastic about the PW1500G and PW1100G. I know why I developed technology to be ahead of what GE or RR could bid.

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WholaLottaLove
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 8:03 pm

lightsaber wrote:
5. Low turbine tech. See LEAP-1B and take it a generation forward. Traditionally, I have been a fan of Pratt being the leader here, but GE stole the right Pratt people. See the incredible efficiency bump of the PW1100G with the low turbine enhancement.


First of all, thank you for your post Lightsaber, enlightening as always! Quick question on the highlighted part: Isn't MTU Aero Engines building the LPT and not P&W? Did GE hire MTU's engineers?
 
Airlines0613
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 8:35 pm

lightsaber wrote:
DenverTed wrote:
lightsaber wrote:
1. CMCs, first engine with the tech in commercial service.
2. High Mach # compressor.
3. Enhanced variable cycle tech. For certain the variable turbine cooling of the LEAP. I see actuators being bought for more, but I do not know the specifics.
4. Far more cooling systems than I've ever seen. The turbine clearance control is two generations ahead of anything I've ever seen. In fact, it is was Lefebvre (one of the great chief engineers of engine design) presented in 1995 to graduate students (me), GE, Pratt, and RR. Apparently another grad student listened and made sure this happened. The problem for me is which of my three grad school friends who attended that lecture made it happen. And which of Lefebvre's variable cycle ideas..
5. Low turbine tech. See LEAP-1B and take it a generation forward. Traditionally, I have been a fan of Pratt being the leader here, but GE stole the right Pratt people. See the incredible efficiency bump of the PW1100G with the low turbine enhancement.
6. Fan blade tip Mach number, without a GTF a required tech for installing the low turbine tech. You get one guess why Pratt is so far behind in this tech.
7. Enhanced materials in combustor (less cooling air)
8. Finally imitating Pratt in modeling airflow through the whole engine. Engines are a system and tweaking how air flows from:
a. Low compressor to high, the GE-90 and TrentXWB botched this to the tune of 1 to 1.5% system fuel burn. Hint, the director if Pratt engine development warned of this botch with the PW6000 early in his carrier. I'm quite certain Steve will never allow this to happen again.
b. High compressor to pre-diffuser. GE was always good at this, modern modeling has allowed a nice fuel efficiency increase.
c. High turbine to low turbine. Seriously, compared to Pratt the LEAP and Txwb are amateur hour here. Seriously? Pratt has only been mocking GE and RR on this since Pratt won the F119 vs. F120 clearly on this tech. I only mention military for the clear' this tech is awesome!' timeframe.

But the people who focus on component efficiency do not get how to maximize system efficiency. 'How can the engine burn 2% less fuel by making the low compressor 1/4% less efficient?'. Because that makes the high compressor and pre-diffuser that much more efficient... Sigh...

Then there are a bunch of little technologies GE is just good at such as pre-diffuserss and shorter combustors. Not to mention fans. GE invests more in fan design because they are the least ready for GTFs. Oops.

The Mach numbers in the high compressor still are not at what that one lecture discussed. That is because bearings and seals are not there (see PW1100G issues).

I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

I haven't yet begun to discuss what wing efficiency is enabled by folding wing tips. I could do a wing with 4% better L/D than the A350 wing, but only with the aspect ratio. At least I wouldn't do it without that extension to mitigate the risks. Nor have I discussed Boeing's latest take on electrical subsystems. I'm still scratching my head

I work aerospace R&D. I've been exposed to a lot. If you need an example of when adding weight improves a product, see A330NEO (extended wingspan that is heavy and much heavier engines)

Lightsaber

Yes, but can you expand on that? :)
When do you think the next new engine will EIS on the 787 or A350, to be the next step beyond the GE9x?

GE at this time, thanks to CMCs can just retrofit. While at it, design a new casing for the LEAP variable cycle tech to cheaply cut fuel burn other 3%. Then might as well update the low turbine and fan, because that isn't being done now as it requires a new casing.

The next step is obvious:
1. GTF version of GE9x.
2. Keep improving bearings and seals for adding back in contra rotation. Oh, need to increase RPM another third for optimal Mach #.
3. CMCs on the 2nd stage of the high turbine (retrofitable with 90% of the benefit).
4. Develop a material (likely a high density CMC) for the first stage of the high turbine. Who knows when this unobtanium that will drop full burn 4% or more will be invented. Whittle, who really thought this out, thought by the 1980s.
5. Add Pratt's variable fan nozzle. Could it be in the GE8x, I just don't know.
6. Add in variable compressor purge. This is only needed at takeoff until above bird heights. This is another obvious variable cycle technology that someone needs to invent to save about 2% in fuel burn.


Then there is other stuff I need to make sure I'm not under NDA. Technology is maturing, so progress is slowing, but there is much to do before the transition to fuel cells generating electricity powering superconducting motors driving variable pitch ducted fans on a BWB.

Os, Airbus has the best small (250 seat) BWB concept I've ever seen! I personally think Boeing will have to partner with who they did on the 747 again for a BWB.

The airframes are about to undergo a design revolution with next generation CFRP weaving and far larger 3D printing. Alas, from when R&D is ready to EIS is about 22 years. We work to much lower TRL levels. But 3D printing is changing all the rules...

Concept presentation to assembled prototype the next week gets management attention.

Lightsaber

Thanks for the explanation lightsaber, really gives an insight on how the GE9X will be a game changer. I can’t wait to see the Boeing 777X fly in the coming months.
 
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Aesma
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Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 8:44 pm

I'm sure Boeing will not want to appear to be rushing certification in any way, shape or form.
New Technology is the name we give to stuff that doesn't work yet. Douglas Adams
 
StTim
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Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 8:52 pm

Every large change of technology on an engine has risks. The almost unforgivable for Pratt is that the failures have been on the supposedly less risky parts.

With so many, as lightsaber describes, all being on one engine then the chances of one or more having major issues increases. One or so I am sure they can deal with and rein back to meet in service and fuel guarantees. More than two they have problems.

No real issues and they have a winner.

What the outcome will be? Well I don’t think anyone really knows yet. Problems, see GTF, can appear well down the line.
 
speedbird52
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 8:58 pm

remcor wrote:
lightsaber wrote:
FrenchPotatoEye wrote:

Could you expand on that?

I echo Zekes remarks to be honest. I see nothing substantially new or ground breaking???


I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

Lightsaber


That's not mocking. He wasn't mocking you, he was reasonably polite about it as far as the internet goes.

It was an extremely politely presented differing opinion. How that turned into mocking is beyond me
 
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 9:04 pm

lightsaber wrote:
There are few new engines that impress me. The GE9x is one. Only a few engines have dramatically altered the competitive landscape:
1. JT8D
2. CF-34 (first 'high bypass')
3. JT9D
4. BMR-7xx (owned high end business jets forever)
4. T700. Finally what the triple spool was capable if.
5. GE-90
6. GTF/LEAP

Lightsaber



Missed one . . .
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SFOtoORD
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 9:04 pm

speedbird52 wrote:
remcor wrote:
lightsaber wrote:

I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

Lightsaber


That's not mocking. He wasn't mocking you, he was reasonably polite about it as far as the internet goes.

It was an extremely politely presented differing opinion. How that turned into mocking is beyond me


When one party makes 10 or so well laid out points and then the other party responds poking a hole in one point and then calls the person US-centric (without acknowledging personal bias) it’s not exactly a fully rational debate.
 
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keesje
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Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 9:23 pm

If GE invested so much in the GE9x there would pressure to get significant ROI and the 777X program, as it looks now, won't offer that. Probably they will go for a GENX upgrade using new technology, to become available around 2025, like the geared Ultrafan.
"Never mistake motion for action." Ernest Hemingway
 
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ElroyJetson
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 9:27 pm

lightsaber wrote:
zeke wrote:
ikolkyo wrote:
I’m pretty sure he is referring to major parts like the HPT
that are completely CMC.re

What about the rest of his points?


No they have made repeated false claims on multiple threads like the GE9X is the first to feature CMCs. Am aware 5 areas in the GE9X is seeing CMCs beings used, but it is not the first engine to use it in commercial service.

Every company has a different risk appetite. Pratt seem only to have the appetite for CMCs on rotating parts at this stage, RR on static parts, and GE on both. As they all get more experience, and as the software tools, and manufacturing techniques get developed, the proliferation will expand. It is disingenuous to suggest (“CMCs, first engine with the tech in commercial service.”) that only GE and only the GE9X is using them.

I know Airbus has test flown CMCs on A320, A340-300, A350, and A380, I think these test flights go back to 2010. That means the R&D goes back way further.

Same with the claims about cooling in the GE9X, it is an active area of development all manufacturers are using, eg the cooling on Trent XWB 97 is very different to the Trent XWB 84.

Sorry to disagree with their tiny world (GE, US centric) view on aero engine development.

That being said, I cannot think of a single aero engine which didn’t need modification as a result of testing. That’s what the testing is for so it doesn't happen with Joe Public paying for the ride.

Ok, I'll update first major use if CMCs in the turbine. Yes, CMCs as coatings have been forever.

But what parts, other than ciatings or guide swirlers?

It happens the turbine CMCs are a milestone the industry has been waiting for 35 years.

That is a major leap forward.

In my opinion the GE8x is one generation ahead. The turbine parts will save.

I'm not being US centric, I am focusing on the GE9x.

There are few new engines that impress me. The GE9x is one. Only a few engines have dramatically altered the competitive landscape:
1. JT8D
2. CF-34 (first 'high bypass')
3. JT9D
4. BMR-7xx (owned high end business jets forever)
4. T700. Finally what the triple spool was capable if.
5. GE-90
6. GTF/LEAP

To my knowledge, the GE-9x is the first to use CMCs to reduce fuel burn (other than as another glad it of thermal barrier coating).

Please provide a link before accusing me if falsehood.

RR has great tech, how many times do I have to credit the greatest gas turbine engineer, Whittle (from UK)?

I personally believe the GE9x is what will make the 777x sell. Just as I believe the T500 killed the A346 (I was working the alternative bid, so I'm biased).

I am also very enthusiastic about the PW1500G and PW1100G. I know why I developed technology to be ahead of what GE or RR could bid.

Lightsaber




I always appreciate your posts regarding engine technology. I learn something new virtually every time. From what I have read PW GTF technology and the GE9x are the cutting edge right now. The fact one is primarily used on Airbus aircraft (the A320 Neo and the C series) and the other is Boeing (GE9x) should not make any difference. But this is A.net. Some will make it a partisan issue no matter what you do or say. :)


regards
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SFOtoORD
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Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 9:34 pm

keesje wrote:
If GE invested so much in the GE9x there would pressure to get significant ROI and the 777X program, as it looks now, won't offer that. Probably they will go for a GENX upgrade using new technology, to become available around 2025, like the geared Ultrafan.


Can you explain the logic of your post or some data to back it up? I don’t follow the point.
 
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remcor
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 9:47 pm

SFOtoORD wrote:
speedbird52 wrote:
remcor wrote:

That's not mocking. He wasn't mocking you, he was reasonably polite about it as far as the internet goes.

It was an extremely politely presented differing opinion. How that turned into mocking is beyond me


When one party makes 10 or so well laid out points and then the other party responds poking a hole in one point and then calls the person US-centric (without acknowledging personal bias) it’s not exactly a fully rational debate.


Unless I'm missing something the "mocking" comment by FrenchPotatoEye's was the 8th post in this thread, before anyone laid out anything detailed. Anyway whatever, just thought it was an over-sensitive/hostile comment by the moderator.
 
speedbird52
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 9:57 pm

SFOtoORD wrote:
speedbird52 wrote:
remcor wrote:

That's not mocking. He wasn't mocking you, he was reasonably polite about it as far as the internet goes.

It was an extremely politely presented differing opinion. How that turned into mocking is beyond me


When one party makes 10 or so well laid out points and then the other party responds poking a hole in one point and then calls the person US-centric (without acknowledging personal bias) it’s not exactly a fully rational debate.

Could you expand on that?

I echo Zekes remarks to be honest. I see nothing substantially new or ground breaking???


That is all he said before being accused of "mocking" lightsaber
 
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Revelation
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Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 10:05 pm

keesje wrote:
If GE invested so much in the GE9x there would pressure to get significant ROI and the 777X program, as it looks now, won't offer that. Probably they will go for a GENX upgrade using new technology, to become available around 2025, like the geared Ultrafan.

Some people may have made a similar comment about the GE90 a year or more before 777's first flight, and we all know how that turned out.

SFOtoORD wrote:
Can you explain the logic of your post or some data to back it up? I don’t follow the point.

You may find this link to be helpful.
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Turnhouse1
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Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 10:24 pm

So what level of improved fuel economy does the GE9x offer over the TrentXWB? Will it still be better than the Advance in 2025. As we're always pushed in work, a new technology is all very nice, but does it work better than what went before as otherwise no-one want to pay for it.
 
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keesje
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Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 10:59 pm

I remember from the GE90 GE had am ambitious break-even point, that they probably hit at some point, but not early. Reading Lightsaber's overview of new technology, the GE9x will probably see a high breakeven number too. Probably it is better to spread out the technologic advances than put all your money on 1 horse. That isn't winning the hearts everywhere so far. E.g. US.
"Never mistake motion for action." Ernest Hemingway
 
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Revelation
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Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 11:32 pm

keesje wrote:
I remember from the GE90 GE had am ambitious break-even point, that they probably hit at some point, but not early. Reading Lightsaber's overview of new technology, the GE9x will probably see a high breakeven number too. Probably it is better to spread out the technologic advances than put all your money on 1 horse. That isn't winning the hearts everywhere so far. E.g. US.

You seem to be rubbing the mommy's tummy and deciding the unborn baby's gonna be a failure at age 25, despite the fact that its older family members turned out great.

Maybe we should wait a bit on making such judgements?

Not sure why there's such a rush to make such judgements, though I have a theory or two on the topic.

Maybe we should consider GE has a better idea of what its spending options are and are not than most of us do?

It actually was riding two horses at the same time (A350 and 787) and decided to jump off A350 and focus on the 787, go figure.

Maybe you make more money going with one good horse all your own rather than two or three shared horses?
Wake up to find out that you are the eyes of the world
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tomcat
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Re: Rumour: 777X First Flight Likely Delayed to Year End Due GE9X Issues

Mon Jun 10, 2019 11:44 pm

Faro wrote:
https://www.fool.com/investing/2019/06/08/the-revolutionary-boeing-777x-jet-is-running-behin.aspx


Apparently issues with the GE9X stator actuation mechanism which was the object of a re-design recently. First flight slated before the year end instead of end of June, with EIS for late 2020 or possibly 2021.

Anyone have any details?


Faro


This link doesn't mention anywhere a first flight delayed to year end. All it says is "While Boeing and GE expect to have a fix ready soon, the first flight is likely to slip into July, if not later.".

Worst case, we talk about a few extra weeks delay. Nothing to call home about.
 
Waterbomber2
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Re: 777X First Flight Delayed to Year End Due GE9X Issues

Tue Jun 11, 2019 12:05 am

lightsaber wrote:
FrenchPotatoEye wrote:
lightsaber wrote:
The GE9X is the mist ambitious engine ever. It is a full generation ahead of anything else. So delays are a risk of that level of technology.

Lightsaber


Could you expand on that?

I echo Zekes remarks to be honest. I see nothing substantially new or ground breaking???

1. CMCs, first engine with the tech in commercial service.
2. High Mach # compressor.
3. Enhanced variable cycle tech. For certain the variable turbine cooling of the LEAP. I see actuators being bought for more, but I do not know the specifics.
4. Far more cooling systems than I've ever seen. The turbine clearance control is two generations ahead of anything I've ever seen. In fact, it is was Lefebvre (one of the great chief engineers of engine design) presented in 1995 to graduate students (me), GE, Pratt, and RR. Apparently another grad student listened and made sure this happened. The problem for me is which of my three grad school friends who attended that lecture made it happen. And which of Lefebvre's variable cycle ideas..
5. Low turbine tech. See LEAP-1B and take it a generation forward. Traditionally, I have been a fan of Pratt being the leader here, but GE stole the right Pratt people. See the incredible efficiency bump of the PW1100G with the low turbine enhancement.
6. Fan blade tip Mach number, without a GTF a required tech for installing the low turbine tech. You get one guess why Pratt is so far behind in this tech.
7. Enhanced materials in combustor (less cooling air)
8. Finally imitating Pratt in modeling airflow through the whole engine. Engines are a system and tweaking how air flows from:
a. Low compressor to high, the GE-90 and TrentXWB botched this to the tune of 1 to 1.5% system fuel burn. Hint, the director if Pratt engine development warned of this botch with the PW6000 early in his carrier. I'm quite certain Steve will never allow this to happen again.
b. High compressor to pre-diffuser. GE was always good at this, modern modeling has allowed a nice fuel efficiency increase.
c. High turbine to low turbine. Seriously, compared to Pratt the LEAP and Txwb are amateur hour here. Seriously? Pratt has only been mocking GE and RR on this since Pratt won the F119 vs. F120 clearly on this tech. I only mention military for the clear' this tech is awesome!' timeframe.

But the people who focus on component efficiency do not get how to maximize system efficiency. 'How can the engine burn 2% less fuel by making the low compressor 1/4% less efficient?'. Because that makes the high compressor and pre-diffuser that much more efficient... Sigh...

Then there are a bunch of little technologies GE is just good at such as pre-diffuserss and shorter combustors. Not to mention fans. GE invests more in fan design because they are the least ready for GTFs. Oops.

The Mach numbers in the high compressor still are not at what that one lecture discussed. That is because bearings and seals are not there (see PW1100G issues).

I like how people who don't understand the internals of an engine mock me. Everything I listed is a generation ahead. Everything presents risk being a generation ahead. That means the first flight delay when risk is realized.

I haven't yet begun to discuss what wing efficiency is enabled by folding wing tips. I could do a wing with 4% better L/D than the A350 wing, but only with the aspect ratio. At least I wouldn't do it without that extension to mitigate the risks. Nor have I discussed Boeing's latest take on electrical subsystems. I'm still scratching my head

I work aerospace R&D. I've been exposed to a lot. If you need an example of when adding weight improves a product, see A330NEO (extended wingspan that is heavy and much heavier engines)

Lightsaber


I would like to reply to this.
1. CMC is like pushing the envelope of what has already been done for decades.
Materials science and more materials science. Works well in labo's, in real life operations RR, GE and PW are struggling with this, call it the bleeding edge.
On the Leap, a CMC shroud coating was compromised way ahead of expected.

2. What is a high Mach compressor? You mean like high tip speed on the blades or high compressor face speed?

3. and 4. seems to be about HPT cooling. Not much to see that is worthy of a generation bump.

5. LPT shows nothing worthy of a generation bump compared to the the GEnx generation.

6. Fan blade tip Mach number, what is so special on the GE9X compared to the GE90? The PW GTF fan blades show a lot of aerodynamic improvements that are slightly ahead of the GE90, the GE9X is merely catching up. Nothing worthy of a generation bump versus the Trent XWB.

7. All recent aircraft engines have increased combustor efficiency, through materials and lean combustion processes, etc...

8. Many points that are not verifyable.


I've read through hundreds of GE/PW/RR patents and I think that the technology is still at the dinosaur stage.
In recent times PW is obsessed with reverse combustion GTF's, I call this the reverse combustion WTF's.

I think that the engine manufacturers still can improve the engines a looooooot and I'm making work personally to this end as well.
The GE9X claims a 10% gain over the GE90 and 5% over other widebody engines in operation, but it's very questionnable and not verifyable. What stage of flight are we talking about?

Hardly a generation ahead, hardly ahead at all.
Hardly worthy of the big and expensive redesign that Boeing is doing for the B777 and will be superseeded within 5 years by whatever goes on the A350neo.

I think that a generation bump will happen in the 2020's resulting in 30% lower fuel burn compared to the GE9X/TXWB and then we can talk about a generational advance.
It will involve a major rethink of the turbofan architecture as a whole and not only menial advances in materials, cooling and blade design.

As I said, when I look at turbofans today, I see dinosaurs. I see waste, waste and more waste.
Too many baby steps and the state of the art is laughable, you should see some of these recent patents. People are getting paid to come up with that?

About the delay. I don't see the B777X EISing before 2022.
First flight in 2020 and EIS in 2022 is most plausible.
If QF choose it for project Sunrise, they won't get deliveries until it's almost time for the A350neo.
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