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Amiga500
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Re: So how New is the 777X?

Wed Feb 26, 2020 10:00 am

StTim wrote:
If the system is untestable should it be anywhere near a plane?


Of course it shouldn't.
 
TFawkes
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Re: So how New is the 777X?

Wed Feb 26, 2020 12:24 pm

Amiga500 wrote:
TFawkes wrote:
Faulting Boeing for undertesting an impossible to test system is ridiculous. You have to make some assumptions about human behavior in that scenario, and those assumptions have to be the outcome basis of training. Now, Boeing ROYALLY screwed up pilot training, so you got me there, but the rest of your post is just untrue.


Totally backwards.

You assume it takes X seconds for pilot to respond to scenario Y.

Then design & build systems accordingly.


After all that, blind test a representative sample set of pilots in that scenario to ensure that assumption is correct.

Which is where things are failing currently. Blind tests are not happening.


If you believe that system was untestable, that says more about your understanding than anything else.

No, you have it backwards. You cannot test random systems. It's a mathematical law. Humans aren't deterministic, nondeterministic, or even pseudo-random. They're truly random. You cannot completely test a human, let alone a group of them, and prove they will respond to stimuli with any sort of predictability.

Now, when you introduce training, or mechanisation/machinification of humans, you can force some predictability of their behaviors because of muscle memory effects. The key word is some. However, for that predictability to be valid, the training has to meet certain standards as set out in the fields of education and psychology.

Blind testing doesn't actually prove anything in that instance. Either the training met mathematically proven requirements or it didn't. If you don't form the required basis, all the math beyond the basis does not hold true. This is a standard proof by contradiction any decent student of discrete mathematics should have memorized.

And why test pilots? If your training meets the requirements, any teenager with good reflexes should do.

You cannot test random systems with assurance. That's a mathematical law. It's perfectly valid for a random number generator with an infinite range to produce a billion of the same number in a row before producing other numbers. If it's truly random, that MUST happen over an infinite span of time, yet within a finite span of time, the probability of it being observed is near zero.

Truly random systems are untestable. Humans are effectively untestable in this way. No amount of foot stamping bt the mathematically ill-informed is going to change that.
 
TFawkes
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Re: So how New is the 777X?

Wed Feb 26, 2020 12:29 pm

StTim wrote:
If the system is untestable should it be anywhere near a plane?

Welcome to the sociopathy of engineering. We've seen plenty of unpredictable idiots on our roads, haven't we? We've seen plenty of snap decision panics cause catastrophy and save lives both. Humans under life and death situational stress are not predictable systems by any stretch of the imagination. You cannot test them with any certainty. Simulators will never be the same as the real thing, at least not without a lot of drugs and quantum computer level brain hacking.

Autopilot will eventually make humans a total liability as pilots. Airbus is ahead on this with their Fly By Wire philosophy where the human pilot cannot arrest compete control of the craft. Both Boeing and Airbus are working on automating humans out of the cockpit completely.
 
Amiga500
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Re: So how New is the 777X?

Wed Feb 26, 2020 12:29 pm

Why are you continually going on about random systems?!?

There is nothing random about it.

Furthermore, you again demonstrate your failure to understand the implications of testing, blind or otherwise.

You have ASSUMED that by training someone - they then are able to react as you ASSUME when that trained scenario presents itself. You blind test to prove that ASSUMPTION.
That ASSUMPTION has fed into the entire PROCESS by which you have designed and built your systems.

Theoretical mathematics has very little to do with the problem you are not comprehending.


If we took that to a non-blind test.
When (a few years back) performing CFD simulations of a particular problem.
#1 I would downselect the models that best capture the fundamental characteristics of the problem I want to simulate.
#2 I would then perform an exercise in verification - that is - removing numerical error as best as possible. (i.e. truncation error due to mesh size, or model orders).
#3 I would then optimise my design based on iterations of CFD.
#4 I would then build the component and test it to ensure that performance met with CFD predictions.
[on bigger jobs, you'd build a prototype between steps #2 & #3 and test it to prove accuracy of numerical method]

Verification - "Is my answer to the question correct?"
Validation - "Am I asking the right question?"

You are swimming against the tide - not just me; if it was only me, I'd ignore me too! But your railing against the entire premise of verification and validation that exists across all fields of engineering. That is millions of engineers across centuries of engineering. Good luck with your mission. [BTW - the earth really isn't flat if you fancy going against that too.]
Last edited by Amiga500 on Wed Feb 26, 2020 12:45 pm, edited 1 time in total.
 
StTim
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Re: So how New is the 777X?

Wed Feb 26, 2020 12:38 pm

I have totally lost track of what he is trying to argue. I follow no logical thread in any of the posts so far.
 
Amiga500
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Re: So how New is the 777X?

Wed Feb 26, 2020 12:46 pm

StTim wrote:
I have totally lost track of what he is trying to argue. I follow no logical thread in any of the posts so far.


He's not related to Guy Fawkes anyway.

That fella had his head screwed on. :lol:
 
TFawkes
Posts: 66
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Re: So how New is the 777X?

Wed Feb 26, 2020 1:10 pm

enzo011 wrote:
TFawkes wrote:
Yes you will. I know there's a Nat. Geo. video of them driving a very long Porsche into one (I think it's one of their "busiest/craziest airports in the world"), and the clearance is a mere 1.5" per side getting through the door at the tightest point. Emirates probably has a published guide on what you can take. I know this guy says the car has to be capable of being pushed while in neutral to fly on a passenger plane. That's all single-clutch manuals and all front-wheel automatics, size limits notwithstanding.

But think of all the small Amazon packages flying around with just 1-2 light items inside that are on 1-2 day shipping. When Atlas and Prime Air don't have the capacity, where do those packages go?


Are you talking about this video and the clearance for the car getting into the cargo hold?

https://www.youtube.com/watch?v=0PFCcj_1zAo

No, I posted that one but I'm looking for a better one, where they interview some of the ground crew and show one of their drivers inching a vehicle in there. They do close up shots showing the tiny gap between the vehicle and the walls of the plane.
 
TFawkes
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Re: So how New is the 777X?

Wed Feb 26, 2020 1:18 pm

Amiga500 wrote:
Why are you continually going on about random systems?!?

There is nothing random about it.

Furthermore, you again demonstrate your failure to understand the implications of testing, blind or otherwise.

You have ASSUMED that by training someone - they then are able to react as you ASSUME when that trained scenario presents itself. You blind test to prove that ASSUMPTION.
That ASSUMPTION has fed into the entire PROCESS by which you have designed and built your systems.

Theoretical mathematics has very little to do with the problem you are not comprehending.


If we took that to a non-blind test.
When (a few years back) performing CFD simulations of a particular problem.
#1 I would downselect the models that best capture the fundamental characteristics of the problem I want to simulate.
#2 I would then perform an exercise in verification - that is - removing numerical error as best as possible. (i.e. truncation error due to mesh size, or model orders).
#3 I would then optimise my design based on iterations of CFD.
#4 I would then build the component and test it to ensure that performance met with CFD predictions.
[on bigger jobs, you'd build a prototype between steps #2 & #3 and test it to prove accuracy of numerical method]

Verification - "Is my answer to the question correct?"
Validation - "Am I asking the right question?"

You are swimming against the tide - not just me; if it was only me, I'd ignore me too! But your railing against the entire premise of verification and validation that exists across all fields of engineering. That is millions of engineers across centuries of engineering. Good luck with your mission. [BTW - the earth really isn't flat if you fancy going against that too.]

Sigh, nope. You, have, it, backwards. Start FROM the goal/outcome, prove the mathematical requirements to reach the goal, and then implement a system aligned/compliant to the math. That leaves no assumptions. That's the difference between a REAL process engineer and an outdated old guard who can't learn anything new.

I'm going on about random systems because humans are random systems. The process you all propose is a surefire way to guarantee fatalities. You approach the problem the exact opposite way of how it CAN be solved, let alone should be.

You design the training to match desired outcomes. You design the interface systems to match your proven training. You wire the systems to your cockpit interface correctly. Now you have a verified, valid system, and the testing is worthless. It can't prove anything right or wrong to begin with, and the system is right because it was rooted in proven facts and constructs.

This is why I sincerely doubt any of you are actually engineers, let alone excellent ones. Go out into the research on process and systems engineering. As mind-boggling as it is, I am right, and you are wrong.

Now, back on topic, I am still hunting for that video on driving a car into a passenger 777-300ER's cargo hold. I will find it and post it.
 
morrisond
Topic Author
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Re: So how New is the 777X?

Wed Feb 26, 2020 1:50 pm

TFawkes wrote:
Amiga500 wrote:
Why are you continually going on about random systems?!?

There is nothing random about it.

Furthermore, you again demonstrate your failure to understand the implications of testing, blind or otherwise.

You have ASSUMED that by training someone - they then are able to react as you ASSUME when that trained scenario presents itself. You blind test to prove that ASSUMPTION.
That ASSUMPTION has fed into the entire PROCESS by which you have designed and built your systems.

Theoretical mathematics has very little to do with the problem you are not comprehending.


If we took that to a non-blind test.
When (a few years back) performing CFD simulations of a particular problem.
#1 I would downselect the models that best capture the fundamental characteristics of the problem I want to simulate.
#2 I would then perform an exercise in verification - that is - removing numerical error as best as possible. (i.e. truncation error due to mesh size, or model orders).
#3 I would then optimise my design based on iterations of CFD.
#4 I would then build the component and test it to ensure that performance met with CFD predictions.
[on bigger jobs, you'd build a prototype between steps #2 & #3 and test it to prove accuracy of numerical method]

Verification - "Is my answer to the question correct?"
Validation - "Am I asking the right question?"

You are swimming against the tide - not just me; if it was only me, I'd ignore me too! But your railing against the entire premise of verification and validation that exists across all fields of engineering. That is millions of engineers across centuries of engineering. Good luck with your mission. [BTW - the earth really isn't flat if you fancy going against that too.]

Sigh, nope. You, have, it, backwards. Start FROM the goal/outcome, prove the mathematical requirements to reach the goal, and then implement a system aligned/compliant to the math. That leaves no assumptions. That's the difference between a REAL process engineer and an outdated old guard who can't learn anything new.

I'm going on about random systems because humans are random systems. The process you all propose is a surefire way to guarantee fatalities. You approach the problem the exact opposite way of how it CAN be solved, let alone should be.

You design the training to match desired outcomes. You design the interface systems to match your proven training. You wire the systems to your cockpit interface correctly. Now you have a verified, valid system, and the testing is worthless. It can't prove anything right or wrong to begin with, and the system is right because it was rooted in proven facts and constructs.

This is why I sincerely doubt any of you are actually engineers, let alone excellent ones. Go out into the research on process and systems engineering. As mind-boggling as it is, I am right, and you are wrong.

Now, back on topic, I am still hunting for that video on driving a car into a passenger 777-300ER's cargo hold. I will find it and post it.


It's possible that the extra width of the 777 cargo hold makes it easier to turn the car in the hold as it can't go through the door sideways.
 
Amiga500
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Re: So how New is the 777X?

Wed Feb 26, 2020 1:51 pm

TFawkes wrote:
Sigh, nope. You, have, it, backwards. Start FROM the goal/outcome, prove the mathematical requirements to reach the goal, and then implement a system aligned/compliant to the math. That leaves no assumptions. That's the difference between a REAL process engineer and an outdated old guard who can't learn anything new.


No.
I.
Do.
Not.

Doing it for a living.

[Note - I am not saying you don't start from the goal, that is the requirement. Everything works back from that. But assumptions that feed into the solution will always exist.]


TFawkes wrote:
You design the training to match desired outcomes. You design the interface systems to match your proven training. You wire the systems to your cockpit interface correctly. Now you have a verified, valid system, and the testing is worthless. It can't prove anything right or wrong to begin with, and the system is right because it was rooted in proven facts and constructs.


Once again - you are ASSUMING that your training works. Furthermore, you use the words (i) "proven" - how do you "prove" it without measuring it? How do you measure it without testing it? (ii) verified - how do you verify it without testing it to make sure its doing what you designed it to do? - (iii) valid - how do you know its valid if you aren't testing it to make sure it is doing what you intended it to do?


Perhaps you are in academia - the world of make-believe systems engineering. If you step out into the real world - you'll very soon find out that reality is far too complex for your little mathematical models - and that you have to bound the scope of your problems with ASSUMPTIONS. Those assumptions then need validated. So not only are you testing the implementation of your system, you are testing the assumptions that went into the foundations of your system.


Define a real world problem that you believe can be answered by your academic systems engineering and I'll quickly show you where your making assumptions - or add complexities that will bust you approach.


TFawkes wrote:
This is why I sincerely doubt any of you are actually engineers, let alone excellent ones. Go out into the research on process and systems engineering. As mind-boggling as it is, I am right, and you are wrong.


Award winning.

Now away off back to designing spades for the beach or whatever it is you do.
 
cledaybuck
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Re: So how New is the 777X?

Wed Feb 26, 2020 2:27 pm

What are we even talking about here? Is this still about the 777X?
As we celebrate mediocrity, all the boys upstairs want to see, how much you'll pay for what you used to get for free.
 
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Revelation
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Re: So how New is the 777X?

Wed Feb 26, 2020 3:46 pm

olle wrote:
The main problem of 779is that it seems to be dependent on a generation younger engines in order to stay competitive against the A350-1000 and it needs to be bigger to do so.

When a new genration engines arrives and let us say that both types get the same generation engines not mentin that A350 might get stretched, the advantage if there is any will dissapear.

Sure, that's a threat, but for now just a threat. A351 is not really optimized with regard to its engine so there is room for improvement. As per a different thread the TXWB-84 is really near the design center, the TXWB-97 a push that was made because more thrust was needed as the A351 design was iterated. It'll be interesting to see what happens when A350neo is done: will it still be optimized for A359 size which is doing so well, or be resized to emphasize A351 or a stretch? We keep emphasizing the A351 vs 779 market since we like controversy but it's pretty clear they have the most market traction with A359.

TFawkes wrote:
You assume increased complexity = increased time. I can hand you plenty of algorithmic examples where the opposite occurs. It also comes down to keeping your battery of tests clean of duplicates or superfluous tests. And in the case of testing the airframes themselves, get enough pilots trained and hire the staff to keep the birds in the air practically 24/7 to keep the data flowing. But again, testing is pointless for multiple reasons: either the design was flawless or it wasn't, and if that flaw cannot be covered by the tests you have, then passing all the tests was just an expensive waste of everyone's time while saving no lives. If the design was in fact flawless, the testing was an expensive waste of time that saved no lives. All it did was provide a feel-good stack of papers and ink to imperfect regulators, managers, investors, pilots, and fliers.

The truth is testing is a lie unless you can mathematically prove the battery is closed and complete. If you are capable of creating THAT proof, you were capable of proving the design had no flaws to begin with, meaning you did twice the work in at least twice the time as needed.

I agree. Most engineers will tell you most automated test suites are garbage. Testers tend to get rewarded in proportion to the number of tests they generate, so they tend to do countless variations on themes rather than doing more themes because that's the easy way to make the numbers look good. Most test harnesses need endless maintenance because they depend on unspecified behaviors that change all the time. Most people run software test suites with code coverage tools enabled and find the test suite is hitting at best 30-50% of the code so >= 50% of the code is not tested.
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Noshow
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Re: So how New is the 777X?

Wed Feb 26, 2020 3:49 pm

What consequences has the 777X structural test had? Is the structure being changed again? Can it remain the same? Is the flight altitude limited for some time?
 
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scbriml
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Re: So how New is the 777X?

Wed Feb 26, 2020 3:54 pm

morrisond wrote:
It's possible that the extra width of the 777 cargo hold makes it easier to turn the car in the hold as it can't go through the door sideways.


The extra width that nobody's been able to confirm yet? Why would boeing build the underfloor cargo holds on a 777 to be any wider than required for side-by-side LD3s?
Time flies like an arrow. Fruit flies like a banana!
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CALTECH
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Re: So how New is the 777X?

Wed Feb 26, 2020 3:57 pm

morrisond wrote:
New Fuselage Ribs (at least in the topside no idea about the lower lobe)


United857 wrote:
F
In order to get an extra 4 inches of cabin width to accommodate 18-inch wide seats 10 abreast, the fuselage ribs had to be reprofiled to be significantly shorter. From a load-bearing perspective, this completely changes the way the fuselage behaves under load, even though the outer diameter is the same, and thus in my opinion should not be considered the "same" fuselage. In addition, the fuselage skin is now made from aluminum lithium to save weight, instead of simply aluminum, which again changes the overall load-bearing properties.


Do you guys have a reference for these fuselage ribs ? Know there are some in the wings and sometimes in meals served onboard, but can't find them anywhere in the Maintenance Manuals.....
You are here.
 
Amiga500
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Re: So how New is the 777X?

Wed Feb 26, 2020 4:04 pm

Revelation wrote:
I agree. Most engineers will tell you most automated test suites are garbage. Testers tend to get rewarded in proportion to the number of tests they generate, so they tend to do countless variations on themes rather than doing more themes because that's the easy way to make the numbers look good. Most test harnesses need endless maintenance because they depend on unspecified behaviors that change all the time. Most people run software test suites with code coverage tools enabled and find the test suite is hitting at best 30-50% of the code so >= 50% of the code is not tested.


Then that shouldn't be certifiable via Do-178.

If you have a gap in code coverage (usually MCDC gap due to mutually exclusive conditions), the gap must be justified.
 
VC10er
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Re: So how New is the 777X?

Wed Feb 26, 2020 4:43 pm

TFawkes wrote:
StTim wrote:
If the system is untestable should it be anywhere near a plane?

Welcome to the sociopathy of engineering. We've seen plenty of unpredictable idiots on our roads, haven't we? We've seen plenty of snap decision panics cause catastrophy and save lives both. Humans under life and death situational stress are not predictable systems by any stretch of the imagination. You cannot test them with any certainty. Simulators will never be the same as the real thing, at least not without a lot of drugs and quantum computer level brain hacking.

Autopilot will eventually make humans a total liability as pilots. Airbus is ahead on this with their Fly By Wire philosophy where the human pilot cannot arrest compete control of the craft. Both Boeing and Airbus are working on automating humans out of the cockpit completely.


Not even the “Kobiashi Maru” test???
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StTim
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Re: So how New is the 777X?

Wed Feb 26, 2020 4:53 pm

VC10er wrote:
TFawkes wrote:
StTim wrote:
If the system is untestable should it be anywhere near a plane?

Welcome to the sociopathy of engineering. We've seen plenty of unpredictable idiots on our roads, haven't we? We've seen plenty of snap decision panics cause catastrophy and save lives both. Humans under life and death situational stress are not predictable systems by any stretch of the imagination. You cannot test them with any certainty. Simulators will never be the same as the real thing, at least not without a lot of drugs and quantum computer level brain hacking.

Autopilot will eventually make humans a total liability as pilots. Airbus is ahead on this with their Fly By Wire philosophy where the human pilot cannot arrest compete control of the craft. Both Boeing and Airbus are working on automating humans out of the cockpit completely.


Not even the “Kobiashi Maru” test???


Ah but you have to cheat to beat that :lol:
 
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spinotter
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Re: So how New is the 777X?

Wed Feb 26, 2020 4:53 pm

TFawkes wrote:
StTim wrote:
If the system is untestable should it be anywhere near a plane?

Welcome to the sociopathy of engineering. We've seen plenty of unpredictable idiots on our roads, haven't we? We've seen plenty of snap decision panics cause catastrophy and save lives both. Humans under life and death situational stress are not predictable systems by any stretch of the imagination. You cannot test them with any certainty. Simulators will never be the same as the real thing, at least not without a lot of drugs and quantum computer level brain hacking.

Autopilot will eventually make humans a total liability as pilots. Airbus is ahead on this with their Fly By Wire philosophy where the human pilot cannot arrest compete control of the craft. Both Boeing and Airbus are working on automating humans out of the cockpit completely.


And humans should get out of the driver's seat in both automobiles and airplanes. For every time brilliant human inspiration saved an aircraft or an automobile, ten or twenty accidents happened because of human fallibility. Remember AF447?
 
StTim
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Re: So how New is the 777X?

Wed Feb 26, 2020 5:01 pm

spinotter wrote:
TFawkes wrote:
StTim wrote:
If the system is untestable should it be anywhere near a plane?

Welcome to the sociopathy of engineering. We've seen plenty of unpredictable idiots on our roads, haven't we? We've seen plenty of snap decision panics cause catastrophy and save lives both. Humans under life and death situational stress are not predictable systems by any stretch of the imagination. You cannot test them with any certainty. Simulators will never be the same as the real thing, at least not without a lot of drugs and quantum computer level brain hacking.

Autopilot will eventually make humans a total liability as pilots. Airbus is ahead on this with their Fly By Wire philosophy where the human pilot cannot arrest compete control of the craft. Both Boeing and Airbus are working on automating humans out of the cockpit completely.


And humans should get out of the driver's seat in both automobiles and airplanes. For every time brilliant human inspiration saved an aircraft or an automobile, ten or twenty accidents happened because of human fallibility. Remember AF447?


I suspect that will eventually happen.
 
VSMUT
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Re: So how New is the 777X?

Wed Feb 26, 2020 5:26 pm

JohanTally wrote:
The A35K has been in service for 2 full years but has only garnered 176 orders total so to act like it is in a league of it's own is pretentious. We could also talk about the Airbus management team that keeps popping up in the news for corruption and being hit with billions of dollars in fines with more potentially on the horizon.


The A350-1000 is also part of a family, so Airbus isn't under pressure to push them out at low prices to maintain a production line.

I don't see how Airbus corruption, deplorable as it is, has anything to do with the 777X. That's just a poor attempt at deflection. AFAIK, Air Asia ordered the A330neo, not A350-1000 or 777X.


JohanTally wrote:
A and B intentionally don't overlap models so the 777X program will have it's part of the market as with the A350 program.


Thanks for pointing out the obvious, which I stated as well. They pushed the 777X into the dead VLA territory by doing that.
 
Amiga500
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Re: So how New is the 777X?

Wed Feb 26, 2020 5:52 pm

VSMUT wrote:
They pushed the 777X into the dead VLA territory by doing that.


I suppose that is ultimately the question - how big is too big?

Its a battle of CASM vs. RASM.
 
VSMUT
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Re: So how New is the 777X?

Wed Feb 26, 2020 6:51 pm

Amiga500 wrote:
VSMUT wrote:
They pushed the 777X into the dead VLA territory by doing that.


I suppose that is ultimately the question - how big is too big?

Its a battle of CASM vs. RASM.


*CASK vs RASK
 
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enzo011
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Re: So how New is the 777X?

Wed Feb 26, 2020 10:22 pm

scbriml wrote:
morrisond wrote:
It's possible that the extra width of the 777 cargo hold makes it easier to turn the car in the hold as it can't go through the door sideways.


The extra width that nobody's been able to confirm yet? Why would boeing build the underfloor cargo holds on a 777 to be any wider than required for side-by-side LD3s?



Well Boeing did go beyond the required tests when they had the fuselage failure, so giving extra space when the purpose isn't clear seems par for the course really. Going beyond what is needed needs to be the motto.

I am still baffled by what the poster means by tight fit, does he mean the cargo hold itself, which I showed a picture isn't a factor for cars. Or does he mean the cargo doors, where one would think the wider door of the A350 should be better when the cars barely fit in the 77W. So again, how is it only possible for the 777 to fly cars around in the cargo hold?
 
morrisond
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Re: So how New is the 777X?

Thu Feb 27, 2020 1:44 am

enzo011 wrote:
scbriml wrote:
morrisond wrote:
It's possible that the extra width of the 777 cargo hold makes it easier to turn the car in the hold as it can't go through the door sideways.


The extra width that nobody's been able to confirm yet? Why would boeing build the underfloor cargo holds on a 777 to be any wider than required for side-by-side LD3s?



Well Boeing did go beyond the required tests when they had the fuselage failure, so giving extra space when the purpose isn't clear seems par for the course really. Going beyond what is needed needs to be the motto.

I am still baffled by what the poster means by tight fit, does he mean the cargo hold itself, which I showed a picture isn't a factor for cars. Or does he mean the cargo doors, where one would think the wider door of the A350 should be better when the cars barely fit in the 77W. So again, how is it only possible for the 777 to fly cars around in the cargo hold?


He is a new member and is providing a bunch of valuable information but some of his claims are hard to verify. I have been trying to help but I can't find hold dimensions even in the ACAP's.
 
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kitplane01
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Re: So how New is the 777X?

Thu Feb 27, 2020 2:30 am

morrisond wrote:
So why did Boeing put the engines farther apart on the 777X? I believe this necessitated the bigger tail. Was this due to the wider wingspan? Or was it an Aero advantage or some other reason.

With the same MTOW all things being equal would they not have been smarter to put them in the same place so the tail was smaller (and could have been smaller than 777W) due to lower thrust and longer fuselage length?

Or was it because they are really planning for a much longer 85M -10 and they needed the wider gear/engines for stability and ground handling issues?


They didn't invite me to that meeting, but the normal answer is that it reduces load on the wings. Placing weight further out on the wings reduces the wing structural stress level (which allows one to lighten the wings).
 
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kitplane01
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Re: So how New is the 777X?

Thu Feb 27, 2020 2:31 am

StTim wrote:
TFawkes wrote:
StTim wrote:

I followed the A350 testing closely. Yesthey had to incorporate changes but they did keep pretty close to the initial time schedule.

To think that the 777X won't have to incorporate changes during testing is clutching at straws. The MAX kept to their schedule but had to incorporate changes to MCAS. I think it is fair to say these were rushed. I do not want the same to happen on the 777X on the altar of an unrealistic timeframe.

What makes a 10-month timeframe unrealistic? If the frame was engineered and built right the first time, the testing doesn't serve any purpose other than making the testers feel good. Why not mandate 4-year flight testing timelines?
Why is it invalid for Boeing to provide quantitative analysis that makes physical testing of the same conditions superfluous?


At present I would say that there is a huge question mark over the ability of Boeing to correctly analyse and test boundary conditions in flight systems. Until they can build trust again I would want each one rigourously tested - not signed off by some engineer under huge pressure from management to keep to time and budget.

As a corollary has Boeing shown an ability to engineer and build something right first time over the last frames they have developed?

MAX - No!
787 - No
747-8 - No
KC-46 - No

Not a good track record.

Airbus isn't much better but I would say that the A350 (the incarnation they finally built) is about the best in most current engineering timeframes.


Remind me: What went wrong with the 747-8? I remember a tail flutter issue, but that doesn't strike me as the same level of bad as the others.
 
strfyr51
Posts: 4989
Joined: Tue Apr 10, 2012 5:04 pm

Re: So how New is the 777X?

Thu Feb 27, 2020 3:02 am

VSMUT wrote:
cedarjet wrote:
I am stunned by how few have been sold. In this day and age we’re used to seeing new types go into service with 1,000 preorders, but this bird is at just 309.

Is it jitters because of Boeing’s shortcomings (as an aside, January 2020 was the first month since the 1950s Boeing haven’t booked a single order for a jet airliner), not quite right for the market, lots of young 777-300ERs too young to need replacing...?


Because it was a poorly thought out attempt at competing with the A350-1000, an aircraft Boeing consistently underestimated at the time. To remain competitive they increased the size, so the CASK could be lowered to that of the A350. Unfortunately that also brought it well into VLA territory, and as well all know, the A380 and 747-8 didn't exactly sell in meaningful numbers either.

It didn't really help either that Emirates in particular pushed for it to have ultra-long-range performance. In the end it got too heavy because of that, and the A350 still ended up superseding it in that metric.

Remember, this is an aircraft pushed out by the same management that was behind the 737MAX. Rational long term thinking wasn't their strong side.

your statement is Prejudicial and more than likely without any facts to back it up. the reliability OF the 777 hasn't been matched in any other Airbus program. You just seem to be hacked that Boeing cut into Airbus' hustle. And where in FACT did you get the assertions that the 777X was solely to thwart the A350-1000? Airbus has tried for MANY years to try and one up Boeing with "Me Too" models the A330 was a "Me TOO" for the 767, the original A350 was a "Me TOO" for the 787. So who are YOU kidding? Now Boeing has their model out After Airbus so when it hits the streets? There will BE no Airbus Response! And we'll see who does WHAT and to WHOM in performance and Sales. The Engineers on the 777X are NOT the same Engineers on the 737Max And they won't be the same nor the Management that oversaw the 737Mx program, And? that's if the project management team even still Works FOR Boeing. Were it up to me? They'd be pushing papers in Archives if anything and would NEVER run another major Program on their own. They cost Boeing Plenty but None of that is indicative of EVERY Boeing Program. Look how long the 747 program has been going and is STILL Going. The 767 Program the 777 and 787 Program and the 797 /757 replacement program. Boeing has as much talent in the Seattle Area than Airbus has Worldwide. And? They haven't HAD to support Bribes to seel their Airplanes either!! You want to talk about something? Then Lets talk about THAT!!
 
Reddevil556
Posts: 219
Joined: Thu Dec 27, 2018 2:09 pm

Re: So how New is the 777X?

Thu Feb 27, 2020 3:17 am

I wonder if it’s possible to have a thread about the 777X without fanboys posting pointless posts only to advance their bias. Especially fanboys that are “respected subject matter experts.” Ugh we get it, Boeing is trash, the 777 is trash, and Airbus is a beacon of perfection this world should recognize. But hey this will probably get deleted because I am not being smug in posting drivel instead, just posting an observation.
Jumped out of: C130H, C130J, C17A, C212, CH47, and UH60. Bucket list: C160, A400, C2
 
ZapZac1027
Posts: 3
Joined: Sun Feb 16, 2020 8:44 am

Re: So how New is the 777X?

Thu Feb 27, 2020 3:23 am

I’m not very sure but definitely they have changed the engine from a GE90 to a GE9X.
 
JayinKitsap
Posts: 2221
Joined: Sat Nov 26, 2005 9:55 am

Re: So how New is the 777X?

Thu Feb 27, 2020 4:21 am

cledaybuck wrote:
What are we even talking about here? Is this still about the 777X?


Didn't you see that article about the certification requirement to drop a Ferrari from 30,000 feet to see how big of a crater it makes.

What loading cars into the hold has any connection to the 777X is beyond me.
 
JayinKitsap
Posts: 2221
Joined: Sat Nov 26, 2005 9:55 am

Re: So how New is the 777X?

Thu Feb 27, 2020 4:23 am

Reddevil556 wrote:
I wonder if it’s possible to have a thread about the 777X without fanboys posting pointless posts only to advance their bias. Especially fanboys that are “respected subject matter experts.” Ugh we get it, Boeing is trash, the 777 is trash, and Airbus is a beacon of perfection this world should recognize. But hey this will probably get deleted because I am not being smug in posting drivel instead, just posting an observation.


Yes posts that indicate "Boeing is Doomed!!!" seem to be desired.

Posts that indicate that the 777X is well designed - Oh the Horrors - That couldn't be.
 
Okcflyer
Posts: 658
Joined: Sat May 23, 2015 11:10 pm

Re: So how New is the 777X?

Thu Feb 27, 2020 4:28 am

So far we have, as per my tally, subject to corrections

All New
-vertical stab
-MLG
-wings
-engines
-cockpit avionics
-interior
-aircraft management system (copies from 787)

Heavily modified:
-wingbox, strengthened and more titanium
-main fuselage:
— ring frames re-contoured for about 30% of their full circumference
— enlarged windows
— delta P (fuselage pressure) increases to 6k feet
— skin thickness adjusted for load path changes from above items.
— exit door configuration slight change, same doors carry forward however.

Little to no changes:
- composite floor beams
- freight deck and components
- Horizontal stab
- tail cone
- basic shape and config

Items I’m still wondering about:
- APU — any changes or carry forward?
- hydraulics— of course it’ll be the same basic layout but how many components are new? One would assume only the actuators on the new wing and MLG. Pumps and other items stayed mostly the same?
-pneumatics - assume very few changes except packs
-electrical - assume very few changes
-packs - additional unit or redesigned models to handle larger cabin and higher pressure
 
JohanTally
Posts: 151
Joined: Tue Jun 18, 2019 3:44 am

Re: So how New is the 777X?

Thu Feb 27, 2020 5:43 am

VSMUT wrote:
JohanTally wrote:
The A35K has been in service for 2 full years but has only garnered 176 orders total so to act like it is in a league of it's own is pretentious. We could also talk about the Airbus management team that keeps popping up in the news for corruption and being hit with billions of dollars in fines with more potentially on the horizon.


The A350-1000 is also part of a family, so Airbus isn't under pressure to push them out at low prices to maintain a production line.

I don't see how Airbus corruption, deplorable as it is, has anything to do with the 777X. That's just a poor attempt at deflection. AFAIK, Air Asia ordered the A330neo, not A350-1000 or 777X.


JohanTally wrote:
A and B intentionally don't overlap models so the 777X program will have it's part of the market as with the A350 program.


Thanks for pointing out the obvious, which I stated as well. They pushed the 777X into the dead VLA territory by doing that.


The four engine VLA territory is dead but the 779 is less than 10 feet longer than the 77W. What does that equate to 1 row of business class and one row of economy? Boeing is betting that airlines can support a 4% stretch of the most produced single model of a widebody jet in history. But what do they know
 
rheinwaldner
Posts: 1863
Joined: Wed Jan 02, 2008 4:58 pm

Re: So how New is the 777X?

Thu Feb 27, 2020 5:57 am

TFawkes wrote:
You can ask any competent mathematician or computer scientist about the usefulness of testing, and they'll say the same thing. It's pointless.

That is the dumbest thing I ever read on this page. Working personally in software development I can only imagine that this must be some pseudo-academic pipe dreams.
https://raygun.com/blog/costly-software-errors-history
https://en.wikipedia.org/wiki/List_of_software_bugs
https://outfresh.com/knowledge-base/6-f ... k-testing/

How do you imagine a big software system could work at all, if its defect tracking system (fed by testing) is having ten thousands of records (= found bugs)?

Devs are blind to their own mistakes. Finally, somebody will "test" any system. Bad luck if your customers are the testers and, as a consequence, they loose money or people have to die.
Many things are difficult, all things are possible!
 
User avatar
Chipmunk1973
Posts: 270
Joined: Tue Jun 28, 2016 10:23 am

Re: So how New is the 777X?

Thu Feb 27, 2020 6:29 am

strfyr51 wrote:
And? They haven't HAD to support Bribes to seel their Airplanes either!! You want to talk about something? Then Lets talk about THAT!!


https://en.wikipedia.org/wiki/Darleen_D ... ontroversy

Rgds,
C1973
Cheers,
C1973


B707, B717, B727, B734, B737, B738, B743, B77W, A300, A320, A332, A333, A339, A388, BAe146, Cessna 206.
 
ewt340
Posts: 1272
Joined: Tue Jul 10, 2012 7:22 pm

Re: So how New is the 777X?

Thu Feb 27, 2020 6:32 am

It's an optimized B777W. Not a new aircraft per se. Sure there are lots of changes around them. But the fundamentals stays the same. Re-engine isn't something I'm really excited about after all.
 
Scotron12
Posts: 496
Joined: Fri Mar 01, 2019 2:13 pm

Re: So how New is the 777X?

Thu Feb 27, 2020 8:40 am

ewt340 wrote:
It's an optimized B777W. Not a new aircraft per se. Sure there are lots of changes around them. But the fundamentals stays the same. Re-engine isn't something I'm really excited about after all.


Only thing in common with the 77W is the metal tube...what else is the same...the 777 designator??
 
Noshow
Posts: 1618
Joined: Wed Jun 15, 2016 3:20 pm

Re: So how New is the 777X?

Thu Feb 27, 2020 8:52 am

It's (testflight) cruise level at 20K feet looks to be lower for now.
 
User avatar
enzo011
Posts: 1901
Joined: Tue Jun 21, 2011 8:12 am

Re: So how New is the 777X?

Thu Feb 27, 2020 9:12 am

morrisond wrote:
He is a new member and is providing a bunch of valuable information but some of his claims are hard to verify. I have been trying to help but I can't find hold dimensions even in the ACAP's.



New member? I don't know about that. With the use of VPN's and no cost to opening an account on this site as before it seems easy to just open a new account and to post as a new user. As for valuable information, the same theory was posted by another poster that seems to have disappeared from the forums for one month, patrickjp93, where he posted this,

I don't know if I'd agree on that. One beauty of the 777-300ER for Emirates, oddly enough, is it lets them fly tycoons' cars around the world on passenger-oriented flights. You can't use the A350 for that, too narrow. The 777X family retains some niche but often used capabilities for Emirates that the A350 just does not replace.


On this thread there wasn't an answer on where this poster got his information from either. So that is two threads now where we are being told that the 77W and 777X can load cars that the A350 cannot, but no explanation on how or why this is. On this thread we have the information that the 777 cargo floor is 5.8" wider than the A350 and this allows it to load vehicles the A350 cannot. What vehicles? Don't know, how many? Who cares as the information has been spread now on this thread and is out there for others to use.
 
Scotron12
Posts: 496
Joined: Fri Mar 01, 2019 2:13 pm

Re: So how New is the 777X?

Thu Feb 27, 2020 9:37 am

Think of all the savings not having to rent a car being able to fly with your vehicle tho. Nevermind the transportation cost!

No brainer!
 
Amiga500
Posts: 2645
Joined: Tue Mar 03, 2015 8:22 am

Re: So how New is the 777X?

Thu Feb 27, 2020 10:27 am

TFawkes wrote:
Doing it for a living, even winning awards, does not mean you're good at it. Plenty of managers win tons of money before high-tailing it ahead of catastrophic failure.

Assumptions can be eliminated. Plenty of work in the financial world has proven this over and over again.

No, I don't assume the training works. I prove it will, and then implement the systems the training is valid for.

Nope, academia is the foundation of good engineering, not the other way around. Heck we invented bounded scope. And under the Johnson-Lindenstrauss Lemma I don't have to model based on assumptions. I can take the mathematical PROOF (not model) backward from the final design and not need assumptions for anything. Anyone still starting from assumptions has no business working in this industry.


I give up.

You are completely incorrect when it comes to anything approaching a complex interacting multi-layered system - but you carry on in your academic bubble.
 
StTim
Posts: 3715
Joined: Thu Aug 08, 2013 7:39 am

Re: So how New is the 777X?

Thu Feb 27, 2020 11:06 am

kitplane01 wrote:
StTim wrote:
TFawkes wrote:
What makes a 10-month timeframe unrealistic? If the frame was engineered and built right the first time, the testing doesn't serve any purpose other than making the testers feel good. Why not mandate 4-year flight testing timelines?
Why is it invalid for Boeing to provide quantitative analysis that makes physical testing of the same conditions superfluous?


At present I would say that there is a huge question mark over the ability of Boeing to correctly analyse and test boundary conditions in flight systems. Until they can build trust again I would want each one rigourously tested - not signed off by some engineer under huge pressure from management to keep to time and budget.

As a corollary has Boeing shown an ability to engineer and build something right first time over the last frames they have developed?

MAX - No!
787 - No
747-8 - No
KC-46 - No

Not a good track record.

Airbus isn't much better but I would say that the A350 (the incarnation they finally built) is about the best in most current engineering timeframes.


Remind me: What went wrong with the 747-8? I remember a tail flutter issue, but that doesn't strike me as the same level of bad as the others.

Tail flutter was not expected as per the design. The contributer was suggesting that testing is not expected to find issues and so an abbreviated test plan is realistic. All I was trying to prove is that despite the powerful computing we now have that any test plan should have a margin built in for the unexpected.

Yes it wasn't the most egregious thing found in testing but ...
 
User avatar
PepeTheFrog
Posts: 389
Joined: Mon Dec 16, 2019 10:38 pm

Re: So how New is the 777X?

Thu Feb 27, 2020 11:35 am

TFawkes wrote:
What makes a 10-month timeframe unrealistic? If the frame was engineered and built right the first time, the testing doesn't serve any purpose other than making the testers feel good. Why not mandate 4-year flight testing timelines?


Well, let's have a look at some recent programs:

- 737 MAX: first flight January 2016, EIS May 2017 => 16 months
- A320neo: first flight September 2014, EIS January 2016 => 16 months
- A330neo: first flight October 2017, EIS December 2018 => 14 months
- A350: first flight June 2013, EIS December 2014 => 18 months

Don't underestimate the amount of testing and paper work that needs to be done. The A330neo was already a speed record in terms of certification; 10 months would really be unrealistic.

According to Emirates, first 777-9 delivery is due in Q1 2021 => that would be 12 to 14 months between first flight and EIS.
Good moaning!
 
VSMUT
Posts: 4471
Joined: Mon Aug 08, 2016 11:40 am

Re: So how New is the 777X?

Thu Feb 27, 2020 11:51 am

JohanTally wrote:
The four engine VLA territory is dead but the 779 is less than 10 feet longer than the 77W. What does that equate to 1 row of business class and one row of economy? Boeing is betting that airlines can support a 4% stretch of the most produced single model of a widebody jet in history. But what do they know


The number of engines is irrelevant. Airlines couldn't fill it.


strfyr51 wrote:
your statement is Prejudicial


Thanks. You need to look up how to use capital letters, maybe some spelling checks too. I'm all for letting errors slip, but wow, you are bad at it!


strfyr51 wrote:
You just seem to be hacked that Boeing cut into Airbus' hustle.


Not really. I was pretty vocal about the mess Airbus got themselves into around 15 years ago with the A350mk1, A380 and A340-600E. Right now Boeing is the one messing around, I will criticize them just as much.


strfyr51 wrote:
Airbus has tried for MANY years to try and one up Boeing with "Me Too" models the A330 was a "Me TOO" for the 767, the original A350 was a "Me TOO" for the 787. So who are YOU kidding?


The A330 started out as a regional workhorse, in reality a bigger and more refined A300. It was not a 767 "me too", although it quite handsomely beat it at a later point. The 787 on the other hand was a direct response to the A330. If anything, it was Boeing that followed Airbus on this one.
The A350mk1 was indeed a direct response to the 787, but that mediocre project was thankfully scrapped and restarted as a 777-killer designed from scratch.


strfyr51 wrote:
Now Boeing has their model out After Airbus so when it hits the streets? There will BE no Airbus Response! And we'll see who does WHAT and to WHOM in performance and Sales.


There already is an Airbus response. There are running improvements being added to the A350. Airbus has made no secret of plans to re-engine the A350 in the mid 2020s. Even GE is so confident of the 777X that they are now trying to get an engine onto the next A350 upgrade.


strfyr51 wrote:
The Engineers on the 777X are NOT the same Engineers on the 737Max. And they won't be the same nor the Management that oversaw the 737Mx program, And? that's if the project management team even still Works FOR Boeing.


From what has been uncovered by the 737MAX debacle, the engineers had their hands tied behind their backs by the management. That was the same management that ran 777X.


strfyr51 wrote:
They cost Boeing Plenty but None of that is indicative of EVERY Boeing Program.


Actually it is. There are not many Boeing programs right now that don't have problems. There are quality issues with the 787 and 767 tanker. The 737MAX speaks for itself. From what I have gathered from sources around me, end-of-the-line 737NG customers weren't too impressed either, quality definitely dropped off.
 
User avatar
PepeTheFrog
Posts: 389
Joined: Mon Dec 16, 2019 10:38 pm

Re: So how New is the 777X?

Thu Feb 27, 2020 11:56 am

VSMUT wrote:
strfyr51 wrote:
The Engineers on the 777X are NOT the same Engineers on the 737Max. And they won't be the same nor the Management that oversaw the 737Mx program, And? that's if the project management team even still Works FOR Boeing.


From what has been uncovered by the 737MAX debacle, the engineers had their hands tied behind their backs by the management. That was the same management that ran 777X.


Indeed.

The engineers are not the problem. The problem is corporate culture and management, which affect all programs.
Good moaning!
 
morrisond
Topic Author
Posts: 2731
Joined: Thu Jan 07, 2010 12:22 am

Re: So how New is the 777X?

Thu Feb 27, 2020 12:00 pm

PepeTheFrog wrote:
TFawkes wrote:
What makes a 10-month timeframe unrealistic? If the frame was engineered and built right the first time, the testing doesn't serve any purpose other than making the testers feel good. Why not mandate 4-year flight testing timelines?


Well, let's have a look at some recent programs:

- 737 MAX: first flight January 2016, EIS May 2017 => 16 months
- A320neo: first flight September 2014, EIS January 2016 => 16 months
- A330neo: first flight October 2017, EIS December 2018 => 14 months
- A350: first flight June 2013, EIS December 2014 => 18 months

Don't underestimate the amount of testing and paper work that needs to be done. The A330neo was already a speed record in terms of certification; 10 months would really be unrealistic.

According to Emirates, first 777-9 delivery is due in Q1 2021 => that would be 12 to 14 months between first flight and EIS.


To be fair as I was the origin of this part of the discussion - we were talking about First Flight to Certification - not EIS which is usually some months later. I was assuming Certification by next summer 14-15 months and EIS by next Christmas - 21-22 months.
 
Amiga500
Posts: 2645
Joined: Tue Mar 03, 2015 8:22 am

Re: So how New is the 777X?

Thu Feb 27, 2020 12:14 pm

PepeTheFrog wrote:
VSMUT wrote:
strfyr51 wrote:
The Engineers on the 777X are NOT the same Engineers on the 737Max. And they won't be the same nor the Management that oversaw the 737Mx program, And? that's if the project management team even still Works FOR Boeing.


From what has been uncovered by the 737MAX debacle, the engineers had their hands tied behind their backs by the management. That was the same management that ran 777X.


Indeed.

The engineers are not the problem. The problem is corporate culture and management, which affect all programs.


Ahh, well - as much as I'd like to think that the engineers have no blame - there has yet to be an email found that nailed some inept management clown to a wall regarding MCAS.

Part of the job is unfortunately being strong enough to stand up to the powerpoint rangers. A single input system was never a good idea - regardless of its safety categorization.
 
JohanTally
Posts: 151
Joined: Tue Jun 18, 2019 3:44 am

Re: So how New is the 777X?

Thu Feb 27, 2020 12:32 pm

VSMUT wrote:
JohanTally wrote:
The four engine VLA territory is dead but the 779 is less than 10 feet longer than the 77W. What does that equate to 1 row of business class and one row of economy? Boeing is betting that airlines can support a 4% stretch of the most produced single model of a widebody jet in history. But what do they know


"The number of engines is irrelevant. Airlines couldn't fill it."

VSMUT can airlines fill one more row of business class and more row of economy from the 77W? You are naive to think that the extra costs associated with a double decker four engine aircraft are not a factor in their demise. Also the Trent engine on the A380 never hit the performance metrics that RR promised. Air France is scrapping A380s because refitting a aircraft cabin costs 60 million dollars on a aircraft with no secondhand market. When the 77W retirements start we will see if they choose a smaller aircraft or a 4% larger one.
 
Amiga500
Posts: 2645
Joined: Tue Mar 03, 2015 8:22 am

Re: So how New is the 777X?

Thu Feb 27, 2020 1:08 pm

JohanTally wrote:
When the 77W retirements start we will see if they choose a smaller aircraft or a 4% larger one.


It will be very interesting to see.

Of course, we'll need more visibility of where performance of both airframes sit relative to one another.

789 vs A359 would indicate that airlines are happy to take on approximately equivalent CASK with a bigger airframe.
A388 vs 77W indicates the opposite.

Does that mean the yield curve is significantly non-linear across enough routes to matter when going from large to very large capacity?
A quite complex sum for each airline to work out which works best for them.

Either way, they'll have 4 great options to choose from. A330n, 787, A350 & 779.

One thing we can say for definite - none of the above aircraft will dominate their markets like the A330 dominated medium-range and the 77W dominated long-range. Competition is significantly better now.

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