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Aviator34ID
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Apr 24, 2020 9:05 am

Now we are cooking! Let's hope for a ramp up of Boeing activity generally.
 
EK7777
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Apr 24, 2020 9:28 am

Sheet updated.

N779XW now up to 90 hours of flight time.

https://docs.google.com/spreadsheets/d/ ... _GfzQnDhA/
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Apr 24, 2020 9:41 am

EK7777 wrote:
Sheet updated.

N779XW now up to 90 hours of flight time.

https://docs.google.com/spreadsheets/d/ ... _GfzQnDhA/

Thanks for this!
 
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747classic
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Apr 25, 2020 6:58 am

N779XW, April 24th 2020
Image

Original uploaded by Chris Lee at twitter, see : https://twitter.com/propandkerosene/sta ... 0191496192
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Chipmunk1973
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Apr 25, 2020 8:38 am

Apologies if this has been asked or mentioned before. But just by looking at the incredible pic above, it would appear the GE engines are slightly more inboard to the fuselage than the 77W. Is this the case?
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Polot
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Apr 25, 2020 10:59 am

Chipmunk1973 wrote:
Apologies if this has been asked or mentioned before. But just by looking at the incredible pic above, it would appear the GE engines are slightly more inboard to the fuselage than the 77W. Is this the case?

Looking at head on pictures of the 779 versus other 777s I don’t think the engines are any more inboard on the 779. Keep in mind the 779 has a much larger wing, I think that is what is giving you the impression the engines are more inboard as there is more wing stretching past the engines (you are use to equating the wingspan to that of the 77W, when in reality it’s span is greater than the 748’s)
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Apr 25, 2020 11:12 am

77-9 N779XW is scheduled for initial airworthiness aft conditions testing on April 27.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Apr 25, 2020 1:51 pm

Does anyone know what AFT conditions entail?
 
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CCA
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Apr 25, 2020 2:00 pm

Chipmunk1973 wrote:
Apologies if this has been asked or mentioned before. But just by looking at the incredible pic above, it would appear the GE engines are slightly more inboard to the fuselage than the 77W. Is this the case?


The 777X engines are actually further out on the wing than the 777 "classic" due to their size.
Enthusiast
 
TropicalSky
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Apr 25, 2020 2:45 pm

I could be wrong but I believe it to mean AFT CG testing

Opus99 wrote:
Does anyone know what AFT conditions entail?
 
Guillaume787
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Apr 25, 2020 3:05 pm

CCA wrote:
Chipmunk1973 wrote:
Apologies if this has been asked or mentioned before. But just by looking at the incredible pic above, it would appear the GE engines are slightly more inboard to the fuselage than the 77W. Is this the case?


The 777X engines are actually further out on the wing than the 777 "classic" due to their size.


Would this have any implications on stability and handling characteristics? :?:
 
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bikerthai
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Apr 25, 2020 4:08 pm

AFT?

Aircraft Flutter Test?

Just a guess.

Aviation Acronyms says: Aerodynamic Flight Test.

If you add the CG, then aerodynamic flight test makes more sense.

bt
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enzo011
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Apr 25, 2020 6:29 pm

Polot wrote:
Chipmunk1973 wrote:
Apologies if this has been asked or mentioned before. But just by looking at the incredible pic above, it would appear the GE engines are slightly more inboard to the fuselage than the 77W. Is this the case?


Looking at head on pictures of the 779 versus other 777s I don’t think the engines are any more inboard on the 779. Keep in mind the 779 has a much larger wing, I think that is what is giving you the impression the engines are more inboard as there is more wing stretching past the engines (you are use to equating the wingspan to that of the 77W, when in reality it’s span is greater than the 748’s)


CCA wrote:
The 777X engines are actually further out on the wing than the 777 "classic" due to their size.



Here is the ACAPs from Boeing, which if I am reading correctly seems to show that the 77W engines are 9.61m from the center of the fuselage and the 777X will be 10.64m. So as Polot and CCA posted the engines are actually further out than the 77W.

777 ACAP - page 16

777X ACAP - page 13
 
JayinKitsap
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Apr 25, 2020 8:12 pm

enzo011 wrote:
Here is the ACAPs from Boeing, which if I am reading correctly seems to show that the 77W engines are 9.61m from the center of the fuselage and the 777X will be 10.64m. So as Polot and CCA posted the engines are actually further out than the 77W.

777 ACAP - page 16

777X ACAP - page 13


A few years back I recall a discussion, moved out for several factors: a) wing moment - with longer wings the wing bending is less at the new position.
b) there were some airflow and vortex issues, needed to keep or increase the clear distance from the hull with the larger engines.
c) the wing rises from the hull more than other planes, along with moving out this gained height where the engines are located. The height gained is about 0.3M.
 
MileHFL400
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 9:52 am

So seeing as things seem to be returning back to normal at Boeing will XX and XW take flight soon?
Thanks and best Regards
AA
 
Noshow
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 9:58 am

Okay let's climb to cruise altitude now. Good she is flying again.
 
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GEUltraFan9XGTF
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 12:37 pm

Noshow wrote:
Okay let's climb to cruise altitude now. Good she is flying again.


Here comes this mantra again. There has been a narrative being pushed in this thread by certain posters with certain biases to insinuate that the 777X is incapable of flying above 20k. Wonder why the Seattle Time hasn't published your article yet?
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RogerMurdock
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 1:15 pm

Guillaume787 wrote:
CCA wrote:
The 777X engines are actually further out on the wing than the 777 "classic" due to their size.


Would this have any implications on stability and handling characteristics? :?:


Well, yes, that's why they do a robust flight test program. Unlike the MAX, however, the 777 platform being FBW means they can make tons of tiny transparent adjustments to handling if necessary without requiring whole new systems.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 1:35 pm

GEUltraFan9XGTF wrote:
Noshow wrote:
Okay let's climb to cruise altitude now. Good she is flying again.


Here comes this mantra again. There has been a narrative being pushed in this thread by certain posters with certain biases to insinuate that the 777X is incapable of flying above 20k. Wonder why the Seattle Time hasn't published your article yet?

I don't know why people are so hung up on it. I believe high altitude testing is scheduled for a separate frame. Boeing is REALLY focusing on handling characteristics here at least for the first frame and i'm sure this is the effect of the MAX. Go above 20K and then do what? they can allocate that to another frame. I believe frame 3 is scheduled to deal with high altitude testing. Frame 3 might currently be in the process of engine installation i'm unable to confirm though.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 1:39 pm

But what i do wonder is, are they seeing any signs of performance figures? is performing as expected, better than expected with regards to efficiency and all Boeing had promised?
 
Noshow
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 1:42 pm

It's a long range airplane. And it's a logical expectation that if flies above 20k feet. There is no agenda behind it.
The assertive tone of some posters might indicate that there is something more behind it? I am in no way anti Boeing by just mentioning my observation.
 
morrisond
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 1:43 pm

JayinKitsap wrote:
enzo011 wrote:
Here is the ACAPs from Boeing, which if I am reading correctly seems to show that the 77W engines are 9.61m from the center of the fuselage and the 777X will be 10.64m. So as Polot and CCA posted the engines are actually further out than the 77W.

777 ACAP - page 16

777X ACAP - page 13


A few years back I recall a discussion, moved out for several factors: a) wing moment - with longer wings the wing bending is less at the new position.
b) there were some airflow and vortex issues, needed to keep or increase the clear distance from the hull with the larger engines.
c) the wing rises from the hull more than other planes, along with moving out this gained height where the engines are located. The height gained is about 0.3M.


They were just getting ready for the 80-85m 777-10 which at this point in time looks pretty unlikely.
 
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 1:50 pm

Noshow wrote:
It's a long range airplane. And it's a logical expectation that if flies above 20k feet. There is no agenda behind it.
The assertive tone of some posters might indicate that there is something more behind it? I am in no way anti Boeing by just mentioning my observation.

I haven't followed flight testing for a while, but I do recall from the early Boeing 787 flight testing days that there was something along the lines of initial airworthiness testing (might not be the correct term) which was done at low level for a number of flight hours at the start. After that is completed, then they can fly at higher flight levels.
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 2:41 pm

Opus99 wrote:
But what i do wonder is, are they seeing any signs of performance figures? is performing as expected, better than expected with regards to efficiency and all Boeing had promised?


A moot point until they do long range, high altitude testing. And when they do learn this, my guess is two things will happen: 1) they'll keep it a secret for the time being, 2) it will determine how the frame is marketed to the public and more importantly, under NDA. The latter might trickle out to us from loose lipped CEOs. If it's all bad news, probably best for Boeing to just kill it now.
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Stitch
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 3:46 pm

Noshow wrote:
The assertive tone of some posters might indicate that there is something more behind it? I am in no way anti Boeing by just mentioning my observation.


Some have been suggesting that because the fuselage suffered a rupture at 149% of load, that the airframe might not be allowed (by Boeing or the FAA) to fly above 20,000 feet. In (scientific) fact, this is not the case since the airframe would not reach 100% of load at stable cruise, much less 150%.

And since Boeing is suggested in reports to have been pushing conditions beyond what was required in the test, it is possible, if not even probable, the frame would not have failed at 149% of load if they had only been pushing it as hard as they needed, instead of harder.
 
Guillaume787
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 4:12 pm

RogerMurdock wrote:
Guillaume787 wrote:
CCA wrote:
The 777X engines are actually further out on the wing than the 777 "classic" due to their size.


Would this have any implications on stability and handling characteristics? :?:


Well, yes, that's why they do a robust flight test program. Unlike the MAX, however, the 777 platform being FBW means they can make tons of tiny transparent adjustments to handling if necessary without requiring whole new systems.


Thank you for your response and clarification! :bigthumbsup:
 
smartplane
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Apr 26, 2020 7:22 pm

All commercial aviation contracts include condition precedent (CP) clauses. Launch customer buy / sell contracts usually include a side agreement of CP clauses covering minimum and scaled performance parameters.

In these troubled times, no aircraft or engine OEM will want to show their hand. If at or above minimum, a special milestone payment is triggered, which will force launch customers to make a decision - cancel, delay, pay/confirm. If marginal or under minimums, triggers contract re-negotiations, and possibly cancellations. Best to keep quiet for now, model and refine.

Pressure ramps up when more of the test fleet is ready, so delays to test equipment installs, crew and analyst shortages, COVID-related problems, incorporation of improvements................... will assist.
 
Spetsnaz55
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 6:01 pm

Fr24 shows 2 of them up in the air. One following the other. Wonder if glitch or 2nd one is airborne
 
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TUSPHX
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 6:06 pm

Spetsnaz55 wrote:
Fr24 shows 2 of them up in the air. One following the other. Wonder if glitch or 2nd one is airborne

I was wondering the same thing. They have different flight numbers but one has no reg.
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Exrampieyyz
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 6:07 pm

2 777-9 in air right now along with T-33.
BOE 25 N779XW. Oh but 2nd one BOE 1 doesn't show registration and out of RNT so guess just another chase plane? T-33 N109X

BOE 25 HAS disappeared and only BOE1 is there with reg
Last edited by Exrampieyyz on Mon Apr 27, 2020 6:16 pm, edited 1 time in total.
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Spetsnaz55
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 6:15 pm

Yeah it got corrected. Was the chase plane
 
boyspot
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 7:38 pm

Before I say anything else, I am not saying that Boeing has restricted the altitude because of the fuselage rupture. However, I would suggest that those who are saying it is irrelevant don't have enough information to base that on. When working on early flights, you have a lot of unknowns. You don't necessarily have all of the structural models validated, you don't have all of the aero loads and the aeroelastics understood and you haven't validated the flight control responses. The result of all of this is that you back off each element from the intended ultimate limits until you have done sufficient testing to validate the models you were designing with.

When you combine a bunch of the reduced envelopes for the different criteria, you end up with quite a restricted envelope. You gradually push that out. While the ultimate load case is not one you are going to hopefully experience, if you have a failure in testing, you will bring the allowable loads to a subset of what you actually managed in test. Also, while everyone has focused on the percentage at which it fails, that does not account for whether that particular element was expected to fail at 150% or whether it was anticipated to be much stronger in that test scenario (since each element of the structure has multiple load cases to withstand, it might be over-designed for a given test). If the fuselage failed well below what was expected, we wouldn't know that (but Boeing would). This failure would result in bringing back in the allowable loads and that, combined with the other untested elements of the models, might well result in an altitude restriction.

I shall repeat, I am not saying that there is a restriction because of the fuselage failure. I am just saying that no-one outside Boeing can say that it isn't at this point.
 
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Stitch
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 8:19 pm

boyspot wrote:
However, I would suggest that those who are saying it is irrelevant don't have enough information to base that on.


And I would suggest that some of us who are saying it is irrelevant do have enough information to base that on.


boyspot wrote:
When working on early flights, you have a lot of unknowns. You don't necessarily have all of the structural models validated, you don't have all of the aero loads and the aeroelastics understood and you haven't validated the flight control responses. The result of all of this is that you back off each element from the intended ultimate limits until you have done sufficient testing to validate the models you were designing with.


This is true, which is why early flights are dedicated to helping to validate those models and find those limits. But the focus on those early flights are handling characteristics at various speeds, stall recovery, and such. Not high-altitude level cruise because there, the models you are validating are related to cabin noise and Specific Fuel Consumption - not structural load limits. High-altitude level cruise is one of the lower stresses on the airframe so you know if it survives the more stressful tests done earlier in the testing regimen, you know it's going to survive high-altitude cruise.

Also, we need to remember where this test failed - at 149% of Limit Load. Limit Load is the highest load an airframe will ever see in service and still stay in the air. An airframe at level cruise below service ceiling is not going to see Limit Load, much less 149% of it. Boeing's test engineers know with 149% certainty that the 777-9 test frames will be just fine in level cruise at 35,000 feet so they have no worries or fears about sending the frame that high when it is time to do so in the Test Regimen. :bigthumbsup:
 
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GEUltraFan9XGTF
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 8:35 pm

Boeing is under no obligation to tell you armchair flight test pilots and CEOs anything. The conjecture here is baseless fantasy from those who want Boeing to fail (even more).
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9Patch
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 9:22 pm

Stitch wrote:

Some have been suggesting that because the fuselage suffered a rupture at 149% of load, that the airframe might not be allowed (by Boeing or the FAA) to fly above 20,000 feet. In (scientific) fact, this is not the case since the airframe would not reach 100% of load at stable cruise, much less 150%.

And since Boeing is suggested in reports to have been pushing conditions beyond what was required in the test, it is possible, if not even probable, the frame would not have failed at 149% of load if they had only been pushing it as hard as they needed, instead of harder.


So what's the outcome of that failure as far as FAA and EASA certification are concerned?
Do they make Boeing repeat the test (pushing it only as hard as needed) or can they simply pass it based on analysis, like they did with the A380?
Haven't heard anything on this subject in a long time.
 
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Stitch
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 9:51 pm

9Patch wrote:
So what's the outcome of that failure as far as FAA and EASA certification are concerned? Do they make Boeing repeat the test (pushing it only as hard as needed) or can they simply pass it based on analysis, like they did with the A380?


Considering how close it was to Ultimate Load, I would expect the certification agencies to accept the results based on analysis (provided, of course, that Boeing identifies why it failed where and how it did and how they corrected it).
 
boyspot
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 9:57 pm

Stitch wrote:
Also, we need to remember where this test failed - at 149% of Limit Load. Limit Load is the highest load an airframe will ever see in service and still stay in the air. An airframe at level cruise below service ceiling is not going to see Limit Load, much less 149% of it. Boeing's test engineers know with 149% certainty that the 777-9 test frames will be just fine in level cruise at 35,000 feet so they have no worries or fears about sending the frame that high when it is time to do so in the Test Regimen. :bigthumbsup:


As I mentioned, 149% of the limit load case does not mean 149% of the intended max stress for that area. In the 150% limit load case, it is entirely plausible that the area in question was supposed to be well below its individual limit. Its limit might be defined by a different load case. The failure at that area could actually be significantly different from what was modeled and not within 1%. That might not be the situation here, but that is not apparent from any of the public disclosures. One of the "fun" things about structural testing is discovering just where your FEA was completely wrong about something that you thought was not even close to being a limit case and it turned out it was. An inappropriate mesh in an area that wasn't seen as an issue can prove unfortunate.
 
boyspot
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 10:01 pm

Stitch wrote:
And I would suggest that some of us who are saying it is irrelevant do have enough information to base that on.


If you are on the inside track, fair enough. However, since you won't be advertising that and the site is full of people making very definitive statements that are clearly ill-informed, it is hard to tell who is the one that knows and who is just talking bollocks.
 
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Nomadd
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 10:10 pm

boyspot wrote:
Stitch wrote:
And I would suggest that some of us who are saying it is irrelevant do have enough information to base that on.


If you are on the inside track, fair enough. However, since you won't be advertising that and the site is full of people making very definitive statements that are clearly ill-informed, it is hard to tell who is the one that knows and who is just talking bollocks.

In some cases it's pretty obvious.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 11:03 pm

I definitely agree with stitch here. Looking at the data from today’s flight with stalls and recoveries. I think that would’ve put more stress on the frame than cursing at 35,000 feet
 
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Stitch
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Apr 27, 2020 11:55 pm

boyspot wrote:
As I mentioned, 149% of the limit load case does not mean 149% of the intended max stress for that area. In the 150% limit load case, it is entirely plausible that the area in question was supposed to be well below its individual limit. Its limit might be defined by a different load case. The failure at that area could actually be significantly different from what was modeled and not within 1%. That might not be the situation here, but that is not apparent from any of the public disclosures. One of the "fun" things about structural testing is discovering just where your FEA was completely wrong about something that you thought was not even close to being a limit case and it turned out it was. An inappropriate mesh in an area that wasn't seen as an issue can prove unfortunate.


A fair point, however if it was a failure of a type that was could or would directly impact the flight test program, I would have expected Boeing to suspend the flight test program for a period until it was addressed. I recall when the 787 was experiencing de-lamination issues with the Side-of-Body join at levels just beyond Limit Load (much less Ultimate Load) during ground testing that prevented ZA001 from performing First Flight because the flight test program would have had to operate under significant restrictions.


boyspot wrote:
If you are on the inside track, fair enough. However, since you won't be advertising that and the site is full of people making very definitive statements that are clearly ill-informed, it is hard to tell who is the one that knows and who is just talking bollocks.


Also a fair point. Most people asking the question appear to want to know the answer and are not putting it forward for FUD (Fear, Uncertainty and Doubt) purposes and I am trying to provide that answer to the best of my ability.
 
boyspot
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Re: Boeing 777X Testing/Production Thread - 2020

Tue Apr 28, 2020 1:16 am

Stitch wrote:
A fair point, however if it was a failure of a type that was could or would directly impact the flight test program, I would have expected Boeing to suspend the flight test program for a period until it was addressed. I recall when the 787 was experiencing de-lamination issues with the Side-of-Body join at levels just beyond Limit Load (much less Ultimate Load) during ground testing that prevented ZA001 from performing First Flight because the flight test program would have had to operate under significant restrictions.


That could be the case. With delamination, you are now uncertain about material properties. On an old program I was on, we ended up with downgraded limit loads after some physical tests of the actual wing to check we could get an acceptable level of performance. It was a demonstrator so we weren't going to have another one to try. If it is a metallic failure, you at least know what it could achieve so can ramp back your assumptions from that since the material properties should not be in doubt between the static test article and the flight examples. In a decade or two, I will buy the book on the project and find out what really happened this time!
 
JayinKitsap
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Re: Boeing 777X Testing/Production Thread - 2020

Tue Apr 28, 2020 7:45 am

Stitch wrote:
boyspot wrote:
As I mentioned, 149% of the limit load case does not mean 149% of the intended max stress for that area. In the 150% limit load case, it is entirely plausible that the area in question was supposed to be well below its individual limit. Its limit might be defined by a different load case. The failure at that area could actually be significantly different from what was modeled and not within 1%. That might not be the situation here, but that is not apparent from any of the public disclosures. One of the "fun" things about structural testing is discovering just where your FEA was completely wrong about something that you thought was not even close to being a limit case and it turned out it was. An inappropriate mesh in an area that wasn't seen as an issue can prove unfortunate.


A fair point, however if it was a failure of a type that was could or would directly impact the flight test program, I would have expected Boeing to suspend the flight test program for a period until it was addressed. I recall when the 787 was experiencing de-lamination issues with the Side-of-Body join at levels just beyond Limit Load (much less Ultimate Load) during ground testing that prevented ZA001 from performing First Flight because the flight test program would have had to operate under significant restrictions.


Doing FEA meshing around openings with stiffeners and ribs coupled with some torsion as the opening frame is not symmetric (skin one side opening the other) can be very tricky. No one expected it to go there, probably because it isn't a spot that ever sees this specific load combination of full hull pressurization along with the max wing test conditions. It is more likely that the hull pressure was 3/4 of the max when the wing is bent in its limit load condition. The back check of the test load case probably found the FEA predicting failure there of 151 - 152%, but it came in a few percent low.

The hull is pretty much the 77W hull, but the pressure was increased. That was probably reviewed and found that the hull could have a lower altitude from the original 8,000 ft down to 6,000 ft. Prudence may have been to just lower to 6,500 feet, that would be enough to show by calculation the 149% actual case to now be the 152% case.

To validate FEA models one needs lots of data, basically all the data for the area being reviewed. Jumping around with bits of data all around the envelope doesn't allow for more than a spot check. Yes at 25,000 feet and 350 knots with a specific payload it checks, but to really see the information that specific payload and CG need to be run at 250 to max cruise speed. Then do the same at 20,000 feet, etc.
 
Checklist787
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Re: Boeing 777X Testing/Production Thread - 2020

Tue Apr 28, 2020 10:06 am

CCA wrote:
Chipmunk1973 wrote:
Apologies if this has been asked or mentioned before. But just by looking at the incredible pic above, it would appear the GE engines are slightly more inboard to the fuselage than the 77W. Is this the case?


The 777X engines are actually further out on the wing than the 777 "classic" due to their size.


The 777-X engines are further upstream on the all-new CFRP wing exactly as on the 787 for aerodynamic reason ...
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Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Apr 29, 2020 2:46 pm

https://twitter.com/jonostrower/status/ ... 68258?s=21

My 777X friends! WH002 to fly as early as today!
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Apr 29, 2020 2:48 pm

It is also scheduled on flight radar as BOE002 for 10am PST
 
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ER757
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Apr 29, 2020 4:11 pm

Opus99 wrote:
It is also scheduled on flight radar as BOE002 for 10am PST

On Flightaware too - shows 10:10 ETD
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Apr 29, 2020 5:26 pm

Calhoun has confirmed the 777X will have a different type certificate not falling under 777 type certificate. EIS still to be 2021

https://twitter.com/jmhdinger/status/12 ... 92609?s=21
 
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GEUltraFan9XGTF
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Apr 29, 2020 5:32 pm

Opus99 wrote:
Calhoun has confirmed the 777X will have a different type certificate not falling under 777 type certificate. EIS still to be 2021

https://twitter.com/jmhdinger/status/12 ... 92609?s=21


Pretty major development there.
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jeffrey0032j
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Apr 29, 2020 5:32 pm

Opus99 wrote:
Calhoun has confirmed the 777X will have a different type certificate not falling under 777 type certificate. EIS still to be 2021

https://twitter.com/jmhdinger/status/12 ... 92609?s=21

One would wonder what the impact is for the rest of the industry, whether it sets a precedent for other aircraft programs.

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