JoeCanuck
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Wed Feb 13, 2019 9:43 pm

Eyad89 wrote:
It's interesting how all the ultrafan speculations were for them to be on the A380neo, but then Airbus goes ahead and ends A380 production and gets those engines on the A350 instead.

Airbus is going through a huge strategy transformation.



Actually, the Ultrafan applications always included a 350neo. It was the 380neo that was the 'what if' scenario.

This isn't really news, is it? Didn't the leak come in November, based on speculation from job postings? Or is this confirmation of the rumors?

I imagine GE will be announcing a GTF of their own in the near future.

On a slightly different note...I'm not sure why people still doubt the prowess of airline makers to re-engine their products.

Of course Boeing with give the MAX treatment to the 787. It baffles me that anyone would doubt it. They have upgraded the engines of pretty much every jet product they have ever made...multiple times. By the 2025 time frame, I have no doubts that Boeing will be offering all new engines from both RR and GE.

There is nothing that one of the big two can do that the other can't...if they really want to.
What the...?
 
WIederling
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Wed Feb 13, 2019 10:17 pm

bhill wrote:
"Variable pitch?" How much?


90° or thereabouts?
Enough to produce sufficient reverse thrust.
The feature included getting away from discrete reversers.
Would allow to have an _unbroken_ engine nacelle surface
from entry lip to exhaust. a chance for even more laminar flow.

Astafan:
https://en.wikipedia.org/wiki/Turbomeca_Astafan
NK-93:
viewtopic.php?t=764007#p11027379
more types around.
Murphy is an optimist
 
JoeCanuck
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Wed Feb 13, 2019 10:57 pm

WIederling wrote:
bhill wrote:
"Variable pitch?" How much?


90° or thereabouts?
Enough to produce sufficient reverse thrust.
The feature included getting away from discrete reversers.
Would allow to have an _unbroken_ engine nacelle surface
from entry lip to exhaust. a chance for even more laminar flow.

Astafan:
https://en.wikipedia.org/wiki/Turbomeca_Astafan
NK-93:
https://www.airliners.net/forum/viewtop ... #p11027379
more types around.


I like the idea of variable pitch but that's a whole lot of complexity drastically increasing the number of failure points on an engine. The fan would be a regular service item, subject to expensive time/cycle overhauls. The fan and the supporting systems and structures would add weight.

As it is, fans are subject to relatively simple inspections. If there is damage, it's relatively easy to swap out single fan blades.

Lessons learned from their current debacles encourage the KISS principle. I think RR made the right choice.
What the...?
 
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Erebus
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 12:00 am

kmz wrote:
Isn't 2025 also the planned EIS for the NMA? Maybe Airbus wants to create engineering constraints at Boeing by opening a front which was not anticipated?


It's how I play chess. When my opponent makes a move (launch NMA), I can choose to make a defensive move (NMA response), or make an attacking move elsewhere on the board (A350neo). See if I can gain a better material advantage. ;)
 
Vladex
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 12:32 am

Erebus wrote:
kmz wrote:
Isn't 2025 also the planned EIS for the NMA? Maybe Airbus wants to create engineering constraints at Boeing by opening a front which was not anticipated?


It's how I play chess. When my opponent makes a move (launch NMA), I can choose to make a defensive move (NMA response), or make an attacking move elsewhere on the board (A350neo). See if I can gain a better material advantage. ;)


What is NMA and where can I fly that aircraft?
 
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Erebus
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 1:12 am

Vladex wrote:
Erebus wrote:
kmz wrote:
Isn't 2025 also the planned EIS for the NMA? Maybe Airbus wants to create engineering constraints at Boeing by opening a front which was not anticipated?


It's how I play chess. When my opponent makes a move (launch NMA), I can choose to make a defensive move (NMA response), or make an attacking move elsewhere on the board (A350neo). See if I can gain a better material advantage. ;)


What is NMA and where can I fly that aircraft?


New Midsized Airplane :wave:
 
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flee
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 3:52 am

seabosdca wrote:
par13del wrote:
Correct me if I am wrong, but isn't RR already exclusive on the A350?
Unless you mean RR new tech will never be on a Boeing product, if GTF is the way of the future, its not a specific engine but primary engine technology.

Sorry, I was unclear. I meant that RR would exclusively offer the new engine technology to Airbus, at least for some period of time. The question is whether the 787 re-engine will be RR + GE or GE only.

I don't think it is the airframe manufacturer that is asking for exclusivity - it is usually the engine manufacturer asking for it. The reason could be due to its specialised application on a particular airframe will mean that production runs might be limited. E.g. GE asking for exclusivity on the 77W/779 and RR on the A330Neo/A350.

The UltraFan will be like the RB211 as it will span a few thrust classes - so it can be used on a variety of aircraft. It is just like CFM and PW offering the LEAP and GTF on several airframes.
 
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Matt6461
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 5:05 am

A350NEO, especially with a stretch, means Airbus sets the 777X expiration date prior to its EIS.
That means long-term planners may opt into the A350 family in the interim rather than ordering 777X.

Hopefully this means Boeing launches a new VLA soon.
 
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seabosdca
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 6:43 am

Matt6461 wrote:
A350NEO, especially with a stretch, means Airbus sets the 777X expiration date prior to its EIS.
That means long-term planners may opt into the A350 family in the interim rather than ordering 777X.


Not sure I agree with this. The 777X has a weight problem, but it also has a wing advantage over the A350-1000 and potential for a three- to four-row stretch. I think the OEMs are locked in a game of chicken over A350/777X stretches where the second one moves the other will too. The Ultrafan could also create a renewed engine contest between GE and RR at the 105klb thrust level.
 
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Matt6461
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 6:45 am

seabosdca wrote:
Matt6461 wrote:
A350NEO, especially with a stretch, means Airbus sets the 777X expiration date prior to its EIS.
That means long-term planners may opt into the A350 family in the interim rather than ordering 777X.


Not sure I agree with this. The 777X has a weight problem, but it also has a wing advantage over the A350-1000 and potential for a three- to four-row stretch. I think the OEMs are locked in a game of chicken over A350/777X stretches where the second one moves the other will too. The Ultrafan could also create a renewed engine contest between GE and RR at the 105klb thrust level.


The 777X has ~3% fuel-efficiency advantage over the A35K that is due entirely to its ~5% lower SFC.
Take away the 777X's engine advantage and it is a non-starter. A larger plane with lower efficiency will never be successful; today the A380 has finally proven so.
 
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 6:51 am

Matt6461 wrote:
A350NEO, especially with a stretch, means Airbus sets the 777X expiration date prior to its EIS.
That means long-term planners may opt into the A350 family in the interim rather than ordering 777X.

Hopefully this means Boeing launches a new VLA soon.


A VLA in lieu of what - the NMA or NSA? I can’t imagine three new clean sheet projects, plus a 787neo, in the next 10 years unless Embraer is REALLY ramping up their role quickly.
-Dave


MAX’d out on MAX threads. If you are starting a thread, and it’s about the MAX - stop. There’s already a thread that covers it.
 
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GEUltraFan9XGTF
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 6:59 am

Matt6461 wrote:
A350NEO, especially with a stretch, means Airbus sets the 777X expiration date prior to its EIS.
That means long-term planners may opt into the A350 family in the interim rather than ordering 777X.

Hopefully this means Boeing launches a new VLA soon.


And anyone who bets their farm on yet another RR miracle engine, delivered on time, is smoking something good. I expect all sorts of PW-like teething issues, plus lots of Brexit headaches. The timetable for UltraFan will be more 2025-2030 than 2025. For those who need reliable capacity and efficiency now: the 77X is available and and will have a segment of the market to itself for nearly a decade.
© 2019. All statements are my own. The use of my statements, including by journalists, YouTube vloggers like "DJ's Aviation", etc. without my written consent is strictly prohibited.
 
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:02 am

PlanesNTrains wrote:
Matt6461 wrote:
A350NEO, especially with a stretch, means Airbus sets the 777X expiration date prior to its EIS.
That means long-term planners may opt into the A350 family in the interim rather than ordering 777X.

Hopefully this means Boeing launches a new VLA soon.


A VLA in lieu of what - the NMA or NSA? I can’t imagine three new clean sheet projects, plus a 787neo, in the next 10 years unless Embraer is REALLY ramping up their role quickly.


I have my doubts about NMA business case viability, especially as sketched by Boeing as a lower-risk variant relying on "LEAP 1.5" engines.
NSA and VLA are doable together, especially considering Embraer's resources, but I have my doubts about the long-term viability of short-hauler business as well: this sector seems poised to become a commodity similar to family sedans or cargo ships. I.e. not a high-margin business that justifies huge investment by first-world firms with first-world labor costs.

That would leave only the VLA project (and a 787MAX).

Realistically, however, I see a Boeing VLA project on a ~2030+ timeline given conventional thinking on these matters. I hope my social evaluation of conventional thought and its myopia is wrong because I think this conventional thought is based on incorrect technical/economic fundamentals.
 
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:07 am

Matt6461 wrote:
PlanesNTrains wrote:
Matt6461 wrote:
A350NEO, especially with a stretch, means Airbus sets the 777X expiration date prior to its EIS.
That means long-term planners may opt into the A350 family in the interim rather than ordering 777X.

Hopefully this means Boeing launches a new VLA soon.


A VLA in lieu of what - the NMA or NSA? I can’t imagine three new clean sheet projects, plus a 787neo, in the next 10 years unless Embraer is REALLY ramping up their role quickly.


I have my doubts about NMA business case viability, especially as sketched by Boeing as a lower-risk variant relying on "LEAP 1.5" engines.
NSA and VLA are doable together, especially considering Embraer's resources, but I have my doubts about the long-term viability of short-hauler business as well: this sector seems poised to become a commodity similar to family sedans or cargo ships. I.e. not a high-margin business that justifies huge investment by first-world firms with first-world labor costs.

That would leave only the VLA project (and a 787MAX).

Realistically, however, I see a Boeing VLA project on a ~2030+ timeline given conventional thinking on these matters. I hope my social evaluation of conventional thought and its myopia is wrong because I think this conventional thought is based on incorrect technical/economic fundamentals.


Well, that’s the opposite problem then - no clean sheet for the next 10 years. :-)
-Dave


MAX’d out on MAX threads. If you are starting a thread, and it’s about the MAX - stop. There’s already a thread that covers it.
 
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:11 am

GEUltraFan9XGTF wrote:
Matt6461 wrote:
A350NEO, especially with a stretch, means Airbus sets the 777X expiration date prior to its EIS.
That means long-term planners may opt into the A350 family in the interim rather than ordering 777X.

Hopefully this means Boeing launches a new VLA soon.


And anyone who bets their farm on yet another RR miracle engine, delivered on time, is smoking something good. I expect all sorts of PW-like teething issues, plus lots of Brexit headaches. The timetable for UltraFan will be more 2025-2030 than 2025. For those who need reliable capacity and efficiency now: the 77X is available and and will have a segment of the market to itself for nearly a decade.


Anyone who bets the farm on reliably-higher fuel burn for 1-3 years versus ~10% lower fuel burn over airframe lifecycle is going to lose his farm.
There's a reason that NEO's outsell CEO's even given the CEO's greater availability.
 
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GEUltraFan9XGTF
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:14 am

Matt6461 wrote:
GEUltraFan9XGTF wrote:
Matt6461 wrote:
A350NEO, especially with a stretch, means Airbus sets the 777X expiration date prior to its EIS.
That means long-term planners may opt into the A350 family in the interim rather than ordering 777X.

Hopefully this means Boeing launches a new VLA soon.


And anyone who bets their farm on yet another RR miracle engine, delivered on time, is smoking something good. I expect all sorts of PW-like teething issues, plus lots of Brexit headaches. The timetable for UltraFan will be more 2025-2030 than 2025. For those who need reliable capacity and efficiency now: the 77X is available and and will have a segment of the market to itself for nearly a decade.


Anyone who bets the farm on reliably-higher fuel burn for 1-3 years versus ~10% lower fuel burn over airframe lifecycle is going to lose his farm.
There's a reason that NEO's outsell CEO's even given the CEO's greater availability.


Ah, but Boeing can also stretch the 779 to a 777-10Max and the game continues.
© 2019. All statements are my own. The use of my statements, including by journalists, YouTube vloggers like "DJ's Aviation", etc. without my written consent is strictly prohibited.
 
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:19 am

GEUltraFan9XGTF wrote:
Matt6461 wrote:
GEUltraFan9XGTF wrote:

And anyone who bets their farm on yet another RR miracle engine, delivered on time, is smoking something good. I expect all sorts of PW-like teething issues, plus lots of Brexit headaches. The timetable for UltraFan will be more 2025-2030 than 2025. For those who need reliable capacity and efficiency now: the 77X is available and and will have a segment of the market to itself for nearly a decade.


Anyone who bets the farm on reliably-higher fuel burn for 1-3 years versus ~10% lower fuel burn over airframe lifecycle is going to lose his farm.
There's a reason that NEO's outsell CEO's even given the CEO's greater availability.


Ah, but Boeing can also stretch the 779 to a 777-10Max and the game continues.


Stretching and regurgitating old planes to ring any remaining breath of life out of them is seemingly what Boeing does best.

Whether that’s a good thing or a bad thing is in the eye of the beholder. The MAX has lower marketshare than the NG. The 747-8i is dead. The 757-300 and 767-400 weren’t exactly sales successes. And now a multi-stretched 777 may get stretched again?
-Dave


MAX’d out on MAX threads. If you are starting a thread, and it’s about the MAX - stop. There’s already a thread that covers it.
 
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:22 am

seabosdca wrote:
Matt6461 wrote:
A350NEO, especially with a stretch, means Airbus sets the 777X expiration date prior to its EIS.
That means long-term planners may opt into the A350 family in the interim rather than ordering 777X.


Not sure I agree with this. The 777X has a weight problem, but it also has a wing advantage over the A350-1000 and potential for a three- to four-row stretch. I think the OEMs are locked in a game of chicken over A350/777X stretches where the second one moves the other will too. The Ultrafan could also create a renewed engine contest between GE and RR at the 105klb thrust level.


The Beluga XL can take fuselage sections roughly 1m larger in diameter than the current Beluga. That's a whole row of seating down the length of the aircraft. Perfect timing to use the Beluga XL and launch a A350-2000 at the same time as the Ultrafan. Airbus would just need to slightly scale the A35K design and give it a little stretch, and maybe some folding wingtips.

But all that aside, I agree with Matt. The A350 with a neo that is scalable, will be a threat to the 777X. It will allow further MTOW increases and the A350 should be able to handle a small stretch too.
 
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Matt6461
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:24 am

GEUltraFan9XGTF wrote:
Ah, but Boeing can also stretch the 779 to a 777-10Max and the game continues.


Only if Boeing wants to play the same game that Airbus played with the A380.
A heavier, older-tech plane will never deliver the economies of scale required for a larger plane (777-10MAX) to beat a smaller plane (A350-2000NEO).

No, for a bigger plane to beat a smaller, the efficiency delta has to be such that the larger plane's extra capacity's CASM is about 50% of the smaller plane's CASM. [note that I'm talking marginal CASM, not absolute plane-level CASM].

That 50% metric is usually unobtainable by the laws of physics and its aerodynamic subsidiary.
The only way for a bigger plane to attain the 50% threshold is to somehow create significantly less weight and drag per passenger.

The only feasible way to accomplish that physics goal is to stack passengers on top of each other so that you get ~twice the passengers for only ~25% more weight and drag.
I.e. the only feasible way is a double-decker.

In the not-so-distant future the only long-haul airliners will be small single-deckers and large double-deckers (until the next drag/pax threshold - triple-deckers - is crossed).
Last edited by Matt6461 on Thu Feb 14, 2019 7:30 am, edited 1 time in total.
 
PlanesNTrains
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:26 am

Matt6461 wrote:
GEUltraFan9XGTF wrote:
Ah, but Boeing can also stretch the 779 to a 777-10Max and the game continues.


Only if Boeing wants to play the same game that Airbus played with the A380.
A heavier, older-tech plane will never deliver the economies of scale required for a larger plane (777-10MAX) to beat a smaller plane (A350-2000NEO).

No, for a bigger plane to beat a smaller, the efficiency delta has to be such that the larger plane's extra capacity's CASM is about 50% of the smaller plane's CASM. [note that I'm talking marginal CASM, not absolute plane-level CASM].

That 50% metric is unobtainable by the laws of physics and its aerodynamic subsidiary.
The only way for a bigger plane to attain the 50% threshold is to somehow create significantly less weight and drag per passenger.

The only feasible way to accomplish that physics goal is to stack passengers on top of each other so that you get ~twice the passengers for only ~25% more weight and drag.
I.e. the only feasible way is a double-decker.

In the not-so-distant future the only long-haul airliners will be small single-deckers and large double-deckers (until the next drag/pax threshold - triple-deckers - is crossed).


Time to start pondering what that VLA might look like. Keesje’ EcoLiner or perhaps something larger?
-Dave


MAX’d out on MAX threads. If you are starting a thread, and it’s about the MAX - stop. There’s already a thread that covers it.
 
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:29 am

PlanesNTrains wrote:
Matt6461 wrote:
GEUltraFan9XGTF wrote:
Ah, but Boeing can also stretch the 779 to a 777-10Max and the game continues.


Only if Boeing wants to play the same game that Airbus played with the A380.
A heavier, older-tech plane will never deliver the economies of scale required for a larger plane (777-10MAX) to beat a smaller plane (A350-2000NEO).

No, for a bigger plane to beat a smaller, the efficiency delta has to be such that the larger plane's extra capacity's CASM is about 50% of the smaller plane's CASM. [note that I'm talking marginal CASM, not absolute plane-level CASM].

That 50% metric is unobtainable by the laws of physics and its aerodynamic subsidiary.
The only way for a bigger plane to attain the 50% threshold is to somehow create significantly less weight and drag per passenger.

The only feasible way to accomplish that physics goal is to stack passengers on top of each other so that you get ~twice the passengers for only ~25% more weight and drag.
I.e. the only feasible way is a double-decker.

In the not-so-distant future the only long-haul airliners will be small single-deckers and large double-deckers (until the next drag/pax threshold - triple-deckers - is crossed).


Time to start pondering what that VLA might look like. Keesje’ EcoLiner or perhaps something larger?


Ironically, it will be a double decker composite twin.
© 2019. All statements are my own. The use of my statements, including by journalists, YouTube vloggers like "DJ's Aviation", etc. without my written consent is strictly prohibited.
 
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Matt6461
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:32 am

PlainsNTrains wrote:
Time to start pondering what that VLA might look like. Keesje’ EcoLiner or perhaps something larger?


Way ahead of you. viewtopic.php?f=5&t=776333

I've been somewhat unique in believing (1) the imminent death of A380 and (2) the superiority of double-deckers for years now.

btw - Keesje's ecoliner is garbage.
 
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:56 am

A clean-sheet, double-decker VLA might be the best and last hope for the return of quad engine airliners. At some point, ETOPs and one-engine out/takeoff requirements may become so onerous for something with 450++t MTOW that it might be more cost-effective to go with something like 4 * 50k engines rather than 2 * 125+k. Especially with ultrafan/GTF-level bypass ratios.
 
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:57 am

Matt6461 wrote:
PlainsNTrains wrote:
Time to start pondering what that VLA might look like. Keesje’ EcoLiner or perhaps something larger?


Way ahead of you. viewtopic.php?f=5&t=776333

I've been somewhat unique in believing (1) the imminent death of A380 and (2) the superiority of double-deckers for years now.

btw - Keesje's ecoliner is garbage.


Well for a long time his pretty picture was all we had.
-Dave


MAX’d out on MAX threads. If you are starting a thread, and it’s about the MAX - stop. There’s already a thread that covers it.
 
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Matt6461
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 8:05 am

PlanesNTrains wrote:
Well for a long time his pretty picture was all we had.


Yeah I get that.
But it also shouldn't take long for true enthusiasts to grok concepts like L/D, weight, and SFC and realize that Keesje's proposal was based on ridiculous numbers.
Pictures are great - they're what motivate us into the space - but after that we need a bit of discipline to learn and critique.
 
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Matt6461
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 8:08 am

JustSomeDood wrote:
A clean-sheet, double-decker VLA might be the best and last hope for the return of quad engine airliners. At some point, ETOPs and one-engine out/takeoff requirements may become so onerous for something with 450++t MTOW that it might be more cost-effective to go with something like 4 * 50k engines rather than 2 * 125+k. Especially with ultrafan/GTF-level bypass ratios.


The simple fact is that the A380 has lower per-pax engine mx costs than 77W.
That's almost entirely due to its quad layout.
There's a lot of advantages to a quad, especially for larger planes where the SFC return to scale from tip-leakage show diminishing returns.

No, the A380 did not fail because it was a quad. That's an excuse.
It failed because it was a terrible design based on a stupid conception of why people travel.
 
WIederling
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 8:23 am

Vladex wrote:
What is NMA and where can I fly that aircraft?

Just around the corner. to the right of that NSA there :-)
Murphy is an optimist
 
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Channex757
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 8:37 am

GEUltraFan9XGTF wrote:
Matt6461 wrote:
GEUltraFan9XGTF wrote:

And anyone who bets their farm on yet another RR miracle engine, delivered on time, is smoking something good. I expect all sorts of PW-like teething issues, plus lots of Brexit headaches. The timetable for UltraFan will be more 2025-2030 than 2025. For those who need reliable capacity and efficiency now: the 77X is available and and will have a segment of the market to itself for nearly a decade.


Anyone who bets the farm on reliably-higher fuel burn for 1-3 years versus ~10% lower fuel burn over airframe lifecycle is going to lose his farm.
There's a reason that NEO's outsell CEO's even given the CEO's greater availability.


Ah, but Boeing can also stretch the 779 to a 777-10Max and the game continues.

Stop trolling for a moment, go away and Google "Pavement loading".

The 773ER has always been a tarmac ripper and you want Boeing to double stretch it with the same number of tyres as well as heavier engines? God help the airport operators.
 
SteinarN
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 11:18 am

Matt6461 wrote:
A350NEO, especially with a stretch, means Airbus sets the 777X expiration date prior to its EIS.
That means long-term planners may opt into the A350 family in the interim rather than ordering 777X.


Bingo!

I've said just this before, the moment Airbus launches an A350Neo the 777X will be dead as a fish on dry land. The reason is, as Matt say, that the B777X is completely dependent on having better engines than the A350 in order to offset its higher weight from the metallic fuselage. Even if the B777X have slightly better wings, the wings alone can not offset the weight penalty from the metallic fuselage, it needs some help from the engines too. I will say that a A350-1000Neo getting about 4-7 percent lover fuel consumption per seat than the B777-9X. Add in significantly more range, like 8.500-9.000NM for the A350-1000Neo versus about 7.500NM for the B777-9X, or alternatively a stretched A350Neo with similar range and passenger capasity as the B777-9X but with 10+ percent or so lower fuel consumption per seat and the B777X has no chance at all to compete. And, there is nothing Boeing or GE can do about this.

Now, with the possibility of the A350Neo getting quite a bit better engines than the B777X from maybe as early as 2025 I cant see any new airline placing an order for the B777X with delivery after the time when an A350Neo would be available.

I have also said that Boeing got it completely wrong when they got themselves in a position where their largest long range wide body have a metallic fuselage while their next largest one are fully composite. And the next largest one will be a 7-8 year older aircraft, while the largest, metallic fuselage will be the newest one.

Airbus was lucky and got this right with the largest one beeing full composite, even if they got in this situation more by chance and luck than by carefull planning. I am discarding the A380 as this aircraft was designed around 1997 to 2000 before a full composite aircraft was seen as a safe and feasible approach.
 
flipdewaf
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 11:45 am

Channex757 wrote:
GEUltraFan9XGTF wrote:
Matt6461 wrote:

Anyone who bets the farm on reliably-higher fuel burn for 1-3 years versus ~10% lower fuel burn over airframe lifecycle is going to lose his farm.
There's a reason that NEO's outsell CEO's even given the CEO's greater availability.


Ah, but Boeing can also stretch the 779 to a 777-10Max and the game continues.

Stop trolling for a moment, go away and Google "Pavement loading".

The 773ER has always been a tarmac ripper and you want Boeing to double stretch it with the same number of tyres as well as heavier engines? God help the airport operators.

Pavement has little or nothing to do with aircraft length but around weight and landing gear geomentry. A simple stretch would not increase pavement loading.

Fred
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 11:54 am

flipdewaf wrote:
Channex757 wrote:
GEUltraFan9XGTF wrote:

Ah, but Boeing can also stretch the 779 to a 777-10Max and the game continues.

Stop trolling for a moment, go away and Google "Pavement loading".

The 773ER has always been a tarmac ripper and you want Boeing to double stretch it with the same number of tyres as well as heavier engines? God help the airport operators.

Pavement has little or nothing to do with aircraft length but around weight and landing gear geomentry. A simple stretch would not increase pavement loading.

Fred

Stretches don't come for free. You are contradicting yourself. Those fuselage plugs and cabin furnishings, wing changes and possible engine changes all add up.

Thanks for playing. Try again.
 
JustSomeDood
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 12:06 pm

Channex757 wrote:
flipdewaf wrote:
Channex757 wrote:
Stop trolling for a moment, go away and Google "Pavement loading".

The 773ER has always been a tarmac ripper and you want Boeing to double stretch it with the same number of tyres as well as heavier engines? God help the airport operators.

Pavement has little or nothing to do with aircraft length but around weight and landing gear geomentry. A simple stretch would not increase pavement loading.

Fred

Stretches don't come for free. You are contradicting yourself. Those fuselage plugs and cabin furnishings, wing changes and possible engine changes all add up.

Thanks for playing. Try again.


Pavement loading is based around MTOW, tarmac can't differentiate between weight from fuel and weight from the plane itself. A stretch with the same MTOW will therfore have the same pavement loading.

Thanks for playing. Try again.
Last edited by JustSomeDood on Thu Feb 14, 2019 12:07 pm, edited 1 time in total.
 
flipdewaf
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 12:06 pm

Channex757 wrote:
flipdewaf wrote:
Channex757 wrote:
Stop trolling for a moment, go away and Google "Pavement loading".

The 773ER has always been a tarmac ripper and you want Boeing to double stretch it with the same number of tyres as well as heavier engines? God help the airport operators.

Pavement has little or nothing to do with aircraft length but around weight and landing gear geomentry. A simple stretch would not increase pavement loading.

Fred

Stretches don't come for free. You are contradicting yourself. Those fuselage plugs and cabin furnishings, wing changes and possible engine changes all add up.

Thanks for playing. Try again.


It has been stated many times that the 777 is at the limits for its undercarriage at 775,000lb and that any stretch to the -10 would have to be done within this limit, of course those items will affect empty weight, I was several kg lighter before I started eating so much but my shoes don't know or even care just like the the airport ground services don't.

Playing is always fun when you are winning!

Fred
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Amiga500
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 12:08 pm

Channex757 wrote:
flipdewaf wrote:
Pavement has little or nothing to do with aircraft length but around weight and landing gear geomentry. A simple stretch would not increase pavement loading.

Fred

Stretches don't come for free. You are contradicting yourself. Those fuselage plugs and cabin furnishings, wing changes and possible engine changes all add up.

Thanks for playing. Try again.


I think you are missing his point.

A "simple stretch" does not raise MTOW, but instead swaps range and payload-range for ultimate payload.

Therefore, there is no increase to pavement loading.
 
WIederling
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 12:28 pm

JustSomeDood wrote:
Pavement loading is based around MTOW, tarmac can't differentiate between weight from fuel and weight from the plane itself.


True.
A simple stretch would add 2.2t / m OEW and 1.4..2t / m payload
MZFW markup 3.6 .. 4.2t / m. 3m ~= 2h flying time ?
Murphy is an optimist
 
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GEUltraFan9XGTF
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 12:42 pm

Matt6461 wrote:
GEUltraFan9XGTF wrote:
Ah, but Boeing can also stretch the 779 to a 777-10Max and the game continues.


Only if Boeing wants to play the same game that Airbus played with the A380.
A heavier, older-tech plane will never deliver the economies of scale required for a larger plane (777-10MAX) to beat a smaller plane (A350-2000NEO).

No, for a bigger plane to beat a smaller, the efficiency delta has to be such that the larger plane's extra capacity's CASM is about 50% of the smaller plane's CASM. [note that I'm talking marginal CASM, not absolute plane-level CASM].

That 50% metric is usually unobtainable by the laws of physics and its aerodynamic subsidiary.
The only way for a bigger plane to attain the 50% threshold is to somehow create significantly less weight and drag per passenger.

The only feasible way to accomplish that physics goal is to stack passengers on top of each other so that you get ~twice the passengers for only ~25% more weight and drag.
I.e. the only feasible way is a double-decker.

In the not-so-distant future the only long-haul airliners will be small single-deckers and large double-deckers (until the next drag/pax threshold - triple-deckers - is crossed).


Whatever makes you feel good after the whale's death, man. You're talking about engines that will be available in 5 years at the earliest, barring any trending difficulties, on a frame that hasn't even been announced (350-1100), especially in the shadow of dismal A35K sales. Keep dreamin, yo.
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bigjku
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 12:56 pm

GEUltraFan9XGTF wrote:
Matt6461 wrote:
GEUltraFan9XGTF wrote:
Ah, but Boeing can also stretch the 779 to a 777-10Max and the game continues.


Only if Boeing wants to play the same game that Airbus played with the A380.
A heavier, older-tech plane will never deliver the economies of scale required for a larger plane (777-10MAX) to beat a smaller plane (A350-2000NEO).

No, for a bigger plane to beat a smaller, the efficiency delta has to be such that the larger plane's extra capacity's CASM is about 50% of the smaller plane's CASM. [note that I'm talking marginal CASM, not absolute plane-level CASM].

That 50% metric is usually unobtainable by the laws of physics and its aerodynamic subsidiary.
The only way for a bigger plane to attain the 50% threshold is to somehow create significantly less weight and drag per passenger.

The only feasible way to accomplish that physics goal is to stack passengers on top of each other so that you get ~twice the passengers for only ~25% more weight and drag.
I.e. the only feasible way is a double-decker.

In the not-so-distant future the only long-haul airliners will be small single-deckers and large double-deckers (until the next drag/pax threshold - triple-deckers - is crossed).


Whatever makes you feel good after the whale's death, man. You're talking about engines that will be available in 5 years at the earliest, barring any trending difficulties, on a frame that hasn't even been announced (350-1100), especially in the shadow of dismal A35K sales. Keep dreamin, yo.


Airbus certainly could do this. It’s silly to pretend they can’t hurt the 77X badly if they go down this route.

But the larger risk is bringing the NEO war to this space is identifying the core market and having the A350 move to far up the size, range table. Right now the A351 and the 777X split a somewhat small market. Dropping new engines onto the 787/A359 space is something both airframers better think through first.
 
JustSomeDood
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 1:23 pm

WIederling wrote:
JustSomeDood wrote:
Pavement loading is based around MTOW, tarmac can't differentiate between weight from fuel and weight from the plane itself.


True.
A simple stretch would add 2.2t / m OEW and 1.4..2t / m payload
MZFW markup 3.6 .. 4.2t / m. 3m ~= 2h flying time ?


Indeed, and any A35K stretch will have to hope really hard that the ultrafan makes up enough of this deficit. :)
 
WIederling
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 1:35 pm

JustSomeDood wrote:
WIederling wrote:
JustSomeDood wrote:
Pavement loading is based around MTOW, tarmac can't differentiate between weight from fuel and weight from the plane itself.


True.
A simple stretch would add 2.2t / m OEW and 1.4..2t / m payload
MZFW markup 3.6 .. 4.2t / m. 3m ~= 2h flying time ?


Indeed, and any A35K stretch will have to hope really hard that the ultrafan makes up enough of this deficit. :)


numbers are for 777. X or no X
numbers comb well for both the -200 vs -300 and the -300ER vs -200LR
and I'd guess transferable to the 778X and 779X ( slight mark up due to the slimmed frames needing slightly more "meat" )

Numbers are significantly lower for the A350.
Taking the raw numbers from WP:EN for the -900 and -1000
the fuselage must weigh distinctly less than 1.7t / m. ( number you get from OEW and length delta )
The A350-1000 is a strongly beefed up airframe vs. -900 .
my guess for just the fuselage segment would be 1.2... 1.4 t/m ?
Murphy is an optimist
 
JustSomeDood
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 1:43 pm

WIederling wrote:
JustSomeDood wrote:
WIederling wrote:

True.
A simple stretch would add 2.2t / m OEW and 1.4..2t / m payload
MZFW markup 3.6 .. 4.2t / m. 3m ~= 2h flying time ?


Indeed, and any A35K stretch will have to hope really hard that the ultrafan makes up enough of this deficit. :)


numbers are for 777. X or no X
numbers comb well for both the -200 vs -300 and the -300ER vs -200LR
and I'd guess transferable to the 778X and 779X ( slight mark up due to the slimmed frames needing slightly more "meat" )

Numbers are significantly lower for the A350.
Taking the raw numbers from WP:EN for the -900 and -1000
the fuselage must weigh distinctly less than 1.7t / m. ( number you get from OEW and length delta )
The A350-1000 is a strongly beefed up airframe vs. -900 .
my guess for just the fuselage segment would be 1.2... 1.4 t/m ?


Your assumption implying that the 10m stretch from 200 and 300 hasn't already significantly beefed up the structure, or that the any A35K stretch wouldn't need proportionately more beefing up for longer loads (a ~80m A350 starts looking a lot like a A346 fuselage wise)
 
morrisond
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 1:56 pm

There is also nothing stopping Boeing from extending the 787 Further either.

The wing apparently is good for 280T - it would just need new Gear - Ultrafans on an 787-11 at 270-280T could be quite the plane .
 
flipdewaf
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 2:07 pm

morrisond wrote:
There is also nothing stopping Boeing from extending the 787 Further either.

The wing apparently is good for 280T - it would just need new Gear - Ultrafans on an 787-11 at 270-280T could be quite the plane .

I think the thought of stretching the A35K into the new engines and even growing the engines north of 100k are not sensible. I believe the A35k is somewhat hampered by its higher span wise loading than the A359. My take would be to have an A35K fuselage on the A359 underpinnings and 84klb advance engines with 280t MTOW. At some point when I’m not in hospital with my wife I’ll do some modelling to see where that gets us.

Fred


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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 2:11 pm

JoeCanuck wrote:
Actually, the Ultrafan applications always included a 350neo. It was the 380neo that was the 'what if' scenario.

This isn't really news, is it? Didn't the leak come in November, based on speculation from job postings?

Yes, cf: viewtopic.php?t=1408963
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:03 pm

SteinarN wrote:
Now, with the possibility of the A350Neo getting quite a bit better engines than the B777X from maybe as early as 2025 I cant see any new airline placing an order for the B777X with delivery after the time when an A350Neo would be available.


It's not quite that dire; 5 years of availability is substantial window and the OEM's have continued to move older tech (77W A330CEO) planes based on pricing and timing.

But we agree that Boeing appears to have been outfoxed by Airbus here. I wonder whether Boeing expected Airbus to remain so tied to the A380 that it would never launch the A350NEO that would surely kill it? Boeing benefited enormously from Airbus stupidity on the A380 but it's a bad strategy to assume your opponent will always be dumb.
 
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:06 pm

GEUltraFan9XGTF wrote:
Whatever makes you feel good after the whale's death, man.


It's funny that, depending on a particular point, I can be called an A380 hater in one thread and a mourning A380 fanboy in another.
Hard for some to imagine that one can have clear views independent of any team allegiance.
 
bigjku
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:22 pm

Matt6461 wrote:
SteinarN wrote:
Now, with the possibility of the A350Neo getting quite a bit better engines than the B777X from maybe as early as 2025 I cant see any new airline placing an order for the B777X with delivery after the time when an A350Neo would be available.


It's not quite that dire; 5 years of availability is substantial window and the OEM's have continued to move older tech (77W A330CEO) planes based on pricing and timing.

But we agree that Boeing appears to have been outfoxed by Airbus here. I wonder whether Boeing expected Airbus to remain so tied to the A380 that it would never launch the A350NEO that would surely kill it? Boeing benefited enormously from Airbus stupidity on the A380 but it's a bad strategy to assume your opponent will always be dumb.


I think we are making a ton of assumptions. The first is that the ultra fan will be ready by 2025, the second being that it will be significantly better than the engines on the 777X after a PIP or two. Finally I think assuming a stretch can be easily done and that the market supports this merits more consideration.

On point one RR still has an awful lot on its plate and they aren’t through the woods yet. Lots of posters doubted that this engine could be ready for the NMA but now it’s going to debut on an aircraft that is what...12 years old? The vast majority of the A350 pre EIS orders haven’t even been delivered yet and we want to stick a new engine on it? Will RR have even digested its losses from the previous generation of engines at that point?

Second GE after all isn’t in the business of just conceding the large engine business to RR and I think people here drastically overvalue what a geared fan can do. The engines on the 777x didn’t win just because they were GE. They were legimately considered to be a better offering than what RR had on the table. There also appears a clear upgrade path in adding more CMC materials to the engine over time. And then there is always the fact that GE isn’t exactly prohibited from adding a geared fan to the front end of what appears to be superior core technology.

Finally I don’t doubt that it can be done and maybe should be done but there is a huge cab of worms being opened very casually here. The A350 slides up the scale to where the 1000 size and maybe larger are now optimized. But those and the 777x have a fraction of the sales of the 787 and A359. Presumably the 787 will get new engines too and the 787-10 and maybe an 11 will move into the market of the A359. Is this where everyone involved wants to go?

I expect an A350neo. But I am not sure it’s the surefire winner everyone thinks it is. I would be extremely wary as airbus of moving it up the size/range charts and losing the sweet spot which so far appears to be with the smallest member of the family.
 
SteinarN
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:35 pm

Matt6461 wrote:
SteinarN wrote:
Now, with the possibility of the A350Neo getting quite a bit better engines than the B777X from maybe as early as 2025 I cant see any new airline placing an order for the B777X with delivery after the time when an A350Neo would be available.


It's not quite that dire; 5 years of availability is substantial window and the OEM's have continued to move older tech (77W A330CEO) planes based on pricing and timing.

But we agree that Boeing appears to have been outfoxed by Airbus here. I wonder whether Boeing expected Airbus to remain so tied to the A380 that it would never launch the A350NEO that would surely kill it? Boeing benefited enormously from Airbus stupidity on the A380 but it's a bad strategy to assume your opponent will always be dumb.


You are ofc right regarding 77W/330ceo being sold/delivered several years after newer tech 787/350 have started deliveries in substantial numbers. However, those two models has its development costs paid for a long time ago, so Boeing/Airbus can sell them relatively cheaply and still make some/an acceptable profit. And they sell them cheaply to bridge the production line too.

But this "opportunity" window will not be there for Boeing and the 77X in 2025. Development cost wont be near paid for at that point, and there will be no production line to bridge for a new model, as there is no new model/neo in sight. The only thing that can make Boeing sell more 77X after about 2025 - ofc under the assumption that the 350Neo is ready for service entry in that time frame - is that Boeing/Airbus cant deliver nearly enough 787/350 to satisfy the market. The other option Boeing have is to cut the asking price for the 77X so much that they sell it for a substantial loss or at best break even on a recurring cash flow basis. But that is no viable option either.
Last edited by SteinarN on Thu Feb 14, 2019 7:54 pm, edited 2 times in total.
 
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:43 pm

bigjku wrote:
I think we are making a ton of assumptions. The first is that the ultra fan will be ready by 2025, the second being that it will be significantly better than the engines on the 777X after a PIP or two.


I'm not assuming 2025 but even a slight slippage means the 777X has only 6-7 years at the top.
Re "significantly better" that's not a simple assumption; it's based on the fundamental physics. Ultrafan will have higher thermal efficiency (70 OPR vs. 60) and higher propulsive efficiency (~50% higher BPR and significantly lower specific thrust). Its N2/N1 ratio will be much higher, enabling a faster, more efficient, lighter core (recall that GE9X is heavier than -115B despite its lower thrust - that's because a direct-drive turbine has to add many large, slower, heavier stages).

The biggest drawback of the the next high-BPR generation was going to be much higher nacelle drag but the OEM's are both working on a step-change that greatly reduces the nacelle/fan diameter ratio and, on Ultrafan, shortens the nacelle as well.

If and when Ultrafan comes it will be a game-changer. In fact, given that any advances after Ultrafan will require truly huge fans for ~25 BPR, Ultrafan may be approaching the limit of practical turbofan efficiency.

Airframers should be building their planes to Ultrafan and its contemporaries. Instead Boeing launched the 777X with probably the last direct-drive large turbofan and seems committed to older tech on its NMA as well. I just don't get it.
 
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Matt6461
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 7:52 pm

SteinarN wrote:
The other option Boeing have is to cut the asking price for the 77X so much that they sell it for a substantial loss or at best break even on a recuring cash flow basis. But that is no viable option either.


"Market intelligence", IIRC, says Boeing can build the 77W for less than $100mil right now. I don't expect the 779 to be much above that figure.
So I think there's room for Boeing to see positive cash flow from 779 sales for at least half a decade - whether it's enough to cover the ~$5bn investment is a different story.

It may be that Boeing never expected full recoupment of 777X development costs, but saw no other option at the time to keep its engineers paid and stay at the bleeding edge of wing/engine tech for the next project. Had Boeing not launched 777X it either (1) would have lost the entire market above 787 and a good portion of its engineering talent or (2) would have had to spend ~$15bn on a clean sheet replacement that probably couldn't be pushed out far enough for Ultrafan engines.

Had option (2) been a double-decker of ~450 seats it might have been a world-beater, but maybe the 777X is a placeholder for such a Y3 project next decade, after early 777X death.
 
bigjku
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Re: Airbus A350 to have RR Ultrafan Engines from ~2025, Ostrower

Thu Feb 14, 2019 8:01 pm

Matt6461 wrote:
bigjku wrote:
I think we are making a ton of assumptions. The first is that the ultra fan will be ready by 2025, the second being that it will be significantly better than the engines on the 777X after a PIP or two.


I'm not assuming 2025 but even a slight slippage means the 777X has only 6-7 years at the top.
Re "significantly better" that's not a simple assumption; it's based on the fundamental physics. Ultrafan will have higher thermal efficiency (70 OPR vs. 60) and higher propulsive efficiency (~50% higher BPR and significantly lower specific thrust). Its N2/N1 ratio will be much higher, enabling a faster, more efficient, lighter core (recall that GE9X is heavier than -115B despite its lower thrust - that's because a direct-drive turbine has to add many large, slower, heavier stages).

The biggest drawback of the the next high-BPR generation was going to be much higher nacelle drag but the OEM's are both working on a step-change that greatly reduces the nacelle/fan diameter ratio and, on Ultrafan, shortens the nacelle as well.

If and when Ultrafan comes it will be a game-changer. In fact, given that any advances after Ultrafan will require truly huge fans for ~25 BPR, Ultrafan may be approaching the limit of practical turbofan efficiency.

Airframers should be building their planes to Ultrafan and its contemporaries. Instead Boeing launched the 777X with probably the last direct-drive large turbofan and seems committed to older tech on its NMA as well. I just don't get it.


Is any current aircraft built to accommodate such large bypass ratios and fans though?

As for the death of direct drive, that’s quite possible. But the triple spool was supposed to spell doom as well and that didn’t work out.

FWIW I expect RR to be one of two offerings on the NMA.

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