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

Tue Feb 25, 2020 3:49 am

N779XX showing up on FR24. Sign of progress?
 
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ikolkyo
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Re: Boeing 777X Testing/Production Thread - 2020

Tue Feb 25, 2020 4:30 am

Aviator34ID wrote:
N779XX showing up on FR24. Sign of progress?


That's a good sign itself, it was suppose to fly before the end of the month I believe.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Tue Feb 25, 2020 6:30 am

N779XX has a wet motor engine run yesterday
 
flipdewaf
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Re: Boeing 777X Testing/Production Thread - 2020

Tue Feb 25, 2020 12:01 pm

Opus99 wrote:
N779XX has a wet motor engine run yesterday

Does ‘wet motor’ refer to the engine running on fuel in the engine fuel system but not through a ‘wet’ wing, ie the fuel supplied to the engine from an external system?

Fred


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res77W
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Re: Boeing 777X Testing/Production Thread - 2020

Tue Feb 25, 2020 9:22 pm

qf789 wrote:
ANA first 777-9 has rolled out of final assembly

Image

https://twitter.com/mattcawby/status/12 ... 57600?s=21


That frame looks to only have four doors, rather than five. So the fuselage is built without it rather than a plug?

-Rowen
 
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RRUltrafan
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 26, 2020 1:28 am

Theres a plug in there instead of a door, yeah.
"Everything has an end, but, only the sausage has two" - Albert Einstein
 
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CCA
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 26, 2020 7:18 am

RRUltrafan wrote:
Theres a plug in there instead of a door, yeah.


I'm fairly sure the fuselage section has no door frame so there is no plug, it's built with windows only thus saving the weight of the structure and plug (which interestingly is actually just a door that's closed normally but sealed. The slide pack and door handle are not Installed / removed so a normal inner sidewall can be fitted hiding the door).
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747classic
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 26, 2020 12:31 pm

flipdewaf wrote:
Opus99 wrote:
N779XX has a wet motor engine run yesterday

Does ‘wet motor’ refer to the engine running on fuel in the engine fuel system but not through a ‘wet’ wing, ie the fuel supplied to the engine from an external system?

Fred


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"Wet motoring or cranking ", normally performed after a new engine installation.
The engine is motored by the starter, the ignition CBs are pulled & fuel levers moved to permit fuel flow.
Normally done to purge the preservative fluid out of the engine fuel systems or for checking fuel flow through the FCU.
You wet crank the engine until fuel comes out the jet pipe, then check that the residual fuel drains from the engine.
Normally a "wet motoring " is followed by a "dry motoring" (fuel levers closed) to get rid of all remaining fuel in the lower engine area's (tailpipe and drains) to prevent a tailpipe fire during the next engine start.
Operating a twin over the ocean, you're always one engine failure from a total emergency.
 
airnorth
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 26, 2020 5:52 pm

747classic wrote:
flipdewaf wrote:
Opus99 wrote:
N779XX has a wet motor engine run yesterday

Does ‘wet motor’ refer to the engine running on fuel in the engine fuel system but not through a ‘wet’ wing, ie the fuel supplied to the engine from an external system?

Fred


Sent from my iPhone using Tapatalk


"Wet motoring or cranking ", normally performed after a new engine installation.
The engine is motored by the starter, the ignition CBs are pulled & fuel levers moved to permit fuel flow.
Normally done to purge the preservative fluid out of the engine fuel systems or for checking fuel flow through the FCU.
You wet crank the engine until fuel comes out the jet pipe, then check that the residual fuel drains from the engine.
Normally a "wet motoring " is followed by a "dry motoring" (fuel levers closed) to get rid of all remaining fuel in the lower engine area's (tailpipe and drains) to prevent a tailpipe fire during the next engine start.


Great information, thanks.
 
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RRUltrafan
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 1:00 am

CCA wrote:
RRUltrafan wrote:
Theres a plug in there instead of a door, yeah.


I'm fairly sure the fuselage section has no door frame so there is no plug, it's built with windows only thus saving the weight of the structure and plug (which interestingly is actually just a door that's closed normally but sealed. The slide pack and door handle are not Installed / removed so a normal inner sidewall can be fitted hiding the door).


Wouldn't having a continuous fuselage without plug require a different line for manufacturing from one with a plug. i.e. making it more complicated to sort out parts. Cuz if the door is simply sealed as with a plug, it doesn't require a different fuselage section to be manufactured
"Everything has an end, but, only the sausage has two" - Albert Einstein
 
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bikerthai
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 2:03 am

RRUltrafan wrote:
Wouldn't having a continuous fuselage without plug require a different line for manufacturing from one with a plug. i.e. making it more complicated to sort out parts. Cuz if the door is simply sealed as with a plug, it doesn't require a different fuselage section to be manufactured


This may be true in the old days when major tooling is involved. However with their digital manufacturing process, it's not too big of a deal to build a section without the cutout for the door. The weight saving and having fewer parts may make up for the extra manufacturing planning.

bt
Intelligent seeks knowledge. Enlightened seeks wisdom.
 
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RRUltrafan
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 2:52 am

bikerthai wrote:
RRUltrafan wrote:
Wouldn't having a continuous fuselage without plug require a different line for manufacturing from one with a plug. i.e. making it more complicated to sort out parts. Cuz if the door is simply sealed as with a plug, it doesn't require a different fuselage section to be manufactured


This may be true in the old days when major tooling is involved. However with their digital manufacturing process, it's not too big of a deal to build a section without the cutout for the door. The weight saving and having fewer parts may make up for the extra manufacturing planning.

bt


Thats fair. Would it also come down to the scale of manufacturing, seeing that airbus has the A321neo with plugs for additional seating capacity without creating a separate fuselage section for customers?
"Everything has an end, but, only the sausage has two" - Albert Einstein
 
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ikolkyo
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 3:56 am

First engine run on the 2nd 777X is happening tonight. https://twitter.com/mattcawby/status/12 ... 67520?s=21
 
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PepeTheFrog
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 11:53 am

So why did the static test fail just below 150%? Isn't it the same fuselage and same pressure test as the original 77W in 2003-2004? Did they change the test protocol?
Good moaning!
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 12:11 pm

PepeTheFrog wrote:
So why did the static test fail just below 150%? Isn't it the same fuselage and same pressure test as the original 77W in 2003-2004? Did they change the test protocol?

Apparently they did. Something about doing more than they needed to. What exactly that was I’m not sure
 
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SEPilot
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 12:57 pm

PepeTheFrog wrote:
So why did the static test fail just below 150%? Isn't it the same fuselage and same pressure test as the original 77W in 2003-2004? Did they change the test protocol?

The 779 is pressurized to 6,000 ft, the older 777s were only pressurized to 8,000. That could be the difference.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
Boeingphan
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 1:38 pm

I posted on a another 777 forum but after looking at some random flights from flightaware I've noticed that for the selected flights it has not gone above 20,000ft. Why have they not gone higher than that after 66 plus hours of testing? Seems as though they would be pressurized at 20,000ft so why not climb up to 35k? I wasn't sure if this had anything to do with the static test issue or if anyone has other reasons.
 
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par13del
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 2:02 pm

Boeingphan wrote:
I posted on a another 777 forum but after looking at some random flights from flightaware I've noticed that for the selected flights it has not gone above 20,000ft. Why have they not gone higher than that after 66 plus hours of testing? Seems as though they would be pressurized at 20,000ft so why not climb up to 35k? I wasn't sure if this had anything to do with the static test issue or if anyone has other reasons.

Question has been asked a number of times, so far no one who knows has provided an answer, so best we can do is to sit and wait.
Or we can speculate that the performance of the engines and the aerodynamic changes are so great that there is no benefit to flying above 20k......
 
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Stitch
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 2:41 pm

PepeTheFrog wrote:
So why did the static test fail just below 150%? Isn't it the same fuselage and same pressure test as the original 77W in 2003-2004? Did they change the test protocol?


Yes, Boeing applied more bending force than the certification test required. They might also have pressurized the cabin to more than the 6000 foot equivalent the frame would normally operate at in passenger service.


Boeingphan wrote:
I posted on a another 777 forum but after looking at some random flights from flightaware I've noticed that for the selected flights it has not gone above 20,000ft. Why have they not gone higher than that after 66 plus hours of testing? Seems as though they would be pressurized at 20,000ft so why not climb up to 35k? I wasn't sure if this had anything to do with the static test issue or if anyone has other reasons.


Again, the 777X's flight level during testing has nothing to do with the static test failure. The only way a 777X will ever experience a load like the one that caused the failure is if she pancakes like Air France 447 or slams her aft fuselage into an embankment like Asiana 214. And neither scenario is required under the testing protocols. :lol:

The protocol now is probably to identify the general handling characteristics of the frame and then start moving to finding the outer envelope (flutter tests and such). The high altitude cruise testing is probably farther on into the program.
 
VV
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 2:57 pm

Boeingphan wrote:
I posted on a another 777 forum but after looking at some random flights from flightaware I've noticed that for the selected flights it has not gone above 20,000ft. Why have they not gone higher than that after 66 plus hours of testing? Seems as though they would be pressurized at 20,000ft so why not climb up to 35k? I wasn't sure if this had anything to do with the static test issue or if anyone has other reasons.


In the beginning of flight tests, one of the most important characteristics to validate is the stall characteristics, stall speeds and behavior.
They are also trying to optimize the slat/flap angle settings.

They need to do it for all flap configurations and with landing gear extended/retracted for some flap settings.

They need to do a lot of roller-coaster flight profiles.

Then they also need to confirm the handling characteristics.

To do all the above they do not need to fly very high, but it has to be high enough to allow some margins for recovery.

That's it that's all.

It is much much better to get the configuration confirmed for all the subsequent flight test articles.
It is more reasonable than some other aircraft manufacturers did with their flight test aircraft.
 
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bikerthai
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 3:10 pm

RRUltrafan wrote:
Thats fair. Would it also come down to the scale of manufacturing, seeing that airbus has the A321neo with plugs for additional seating capacity without creating a separate fuselage section for customers?


Yes, that and the fact that the digital manufacturing process that Boeing developed is highly guarded and has not yet flowed through the whole company, not even the 737 line. It would take Airbus a few years to develop their own process.

I see this type of customization will be more standard for future aircraft where fuel efficiency is highly important and any weight you can take off will be worth doing if you have the right manufacturing techniques to do it. For example, for the 787, to get a different skin configuration (with out the plug), you just need different program for the fiber placement machine. The pad-up and for the door does not require any additional tooling or set-up. The placement of the frame and stringers doesn't take any more time, nor does it require any special tooling other than a separate curing tool for the frames around the door area.

For the 737 and A320, keeping the door as a plug may be an advantage for when they swap configuration and may want to put a door back in.

bt
Intelligent seeks knowledge. Enlightened seeks wisdom.
 
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bikerthai
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 3:16 pm

par13del wrote:
Question has been asked a number of times, so far no one who knows has provided an answer, so best we can do is to sit and wait.


LOL. Maybe it's also not the time to ask "Why haven't they tested the engine out condition yet?"

If you think about it, commercial testing is a lot more conservative than you think. The higher you fly the higher the risk and the more mitigation planning you need to have. Pilots will probably tell you that the higher you go, the smaller window you have to stall etc. With all the focus on safety, they are probably not taking any unnecessary risk.

bt
Intelligent seeks knowledge. Enlightened seeks wisdom.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 3:32 pm

Stitch wrote:
PepeTheFrog wrote:
So why did the static test fail just below 150%? Isn't it the same fuselage and same pressure test as the original 77W in 2003-2004? Did they change the test protocol?


Yes, Boeing applied more bending force than the certification test required. They might also have pressurized the cabin to more than the 6000 foot equivalent the frame would normally operate at in passenger service.


Boeingphan wrote:
I posted on a another 777 forum but after looking at some random flights from flightaware I've noticed that for the selected flights it has not gone above 20,000ft. Why have they not gone higher than that after 66 plus hours of testing? Seems as though they would be pressurized at 20,000ft so why not climb up to 35k? I wasn't sure if this had anything to do with the static test issue or if anyone has other reasons.


Again, the 777X's flight level during testing has nothing to do with the static test failure. The only way a 777X will ever experience a load like the one that caused the failure is if she pancakes like Air France 447 or slams her aft fuselage into an embankment like Asiana 214. And neither scenario is required under the testing protocols. :lol:

The protocol now is probably to identify the general handling characteristics of the frame and then start moving to finding the outer envelope (flutter tests and such). The high altitude cruise testing is probably farther on into the program.

Exactly. My take on it is, if that was really an issue they wouldn’t be testing as frequently as they are and they wouldn’t be about to introduce a second frame into the testing schedule with the 3rd on the way. Like you said the static test frame holds no relevance here
 
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CCA
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 3:57 pm

Simply put low speed testing is done at lower altitudes below the flap limit of FL200, you have to start somewhere and it's efficient, going up to FL350 for a single test is a waste of time and money when they can be grouped together for high level testing later.

Regarding 5 door vs 4 door the difference being side panels being window versions or door versions that are brought together during assembly.

Image

While not the correct section the four sides of the barrel make the section as required.
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Nomadd
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 4:30 pm

bikerthai wrote:
Pilots will probably tell you that the higher you go, the smaller window you have to stall etc.
bt

And the more time you have to recover.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 5:49 pm

With WH002 would they have to do all the previous tests that was done in preparation for FF like gauntlet etc? Or is it more straightforward
 
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bikerthai
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 7:45 pm

Nomadd wrote:
bikerthai wrote:
Pilots will probably tell you that the higher you go, the smaller window you have to stall etc.
bt

And the more time you have to recover.



I wrote the above comment before I heard about this:

https://www.aviation24.be/manufacturers ... liability/

Yet, a Boeing T-7A trainer crew recently did it, at 20,000 feet above an Illinois test area, then flew the plane for 48 seconds before restarting the GE F404 engine and landing back at Boeing’s St. Louis site.


bt
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musman9853
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 27, 2020 9:16 pm

ikolkyo wrote:
First engine run on the 2nd 777X is happening tonight. https://twitter.com/mattcawby/status/12 ... 67520?s=21


so could we see whoo2 in the air sometime in the next week?
Welcome to the City Beautiful.
 
smartplane
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 28, 2020 10:24 pm

CCA wrote:
Simply put low speed testing is done at lower altitudes below the flap limit of FL200, you have to start somewhere and it's efficient, going up to FL350 for a single test is a waste of time and money when they can be grouped together for high level testing later.

If performance confidence levels are high, you would think Boeing would have ventured higher to give early customers some morale boosting information, and to discourage the need for A350 top-up / new order dialogue.

Almost as if the FAA, Boeing and / or GE have imposed operating constraints. Or perhaps everyone is just being super conservative post-MAX.
 
smartplane
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 28, 2020 10:26 pm

CCA wrote:
Simply put low speed testing is done at lower altitudes below the flap limit of FL200, you have to start somewhere and it's efficient, going up to FL350 for a single test is a waste of time and money when they can be grouped together for high level testing later.

If performance confidence levels are high, you would think Boeing would have ventured higher to give early customers some morale boosting information, and to discourage the need for A350 top-up / new order dialogue.

Almost as if the FAA, Boeing and / or GE have imposed operating constraints. Or perhaps everyone is just being super conservative post-MAX.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 28, 2020 10:56 pm

smartplane wrote:
CCA wrote:
Simply put low speed testing is done at lower altitudes below the flap limit of FL200, you have to start somewhere and it's efficient, going up to FL350 for a single test is a waste of time and money when they can be grouped together for high level testing later.

If performance confidence levels are high, you would think Boeing would have ventured higher to give early customers some morale boosting information, and to discourage the need for A350 top-up / new order dialogue.

Almost as if the FAA, Boeing and / or GE have imposed operating constraints. Or perhaps everyone is just being super conservative post-MAX.

Why do something you don’t need to when there’s a separate test for it called high altitude tests that have also been reserved for the other test planes coming into the test program? It will get there, just be patient.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Mar 01, 2020 8:45 am

http://kpae.blogspot.com/2020/02/paine- ... ry-29.html

I’m guessing this is was in the paint hangar to be weighed? And then taxi tests from Monday? Or Tuesday?
 
VV
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Mar 01, 2020 9:21 am

Opus99 wrote:
http://kpae.blogspot.com/2020/02/paine-field-february-29.html

I’m guessing this is was in the paint hangar to be weighed? And then taxi tests from Monday? Or Tuesday?


You are probably right.
The tweet says, "777-9 N779XX is being moved out of the paint hangar to the flightline to be fueled."

Interesting that it is already in the stage it will be fueled. It is one of the lasts actions before a real engine run can be done and then followed by all kind of functional tests and then the usual tests before first flight.

Does anyone know what the main purpose of this flight test article is. Is it mostly for avionics or for other things?
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Mar 01, 2020 9:41 am

VV wrote:
Opus99 wrote:
http://kpae.blogspot.com/2020/02/paine-field-february-29.html

I’m guessing this is was in the paint hangar to be weighed? And then taxi tests from Monday? Or Tuesday?


You are probably right.
The tweet says, "777-9 N779XX is being moved out of the paint hangar to the flightline to be fueled."

Interesting that it is already in the stage it will be fueled. It is one of the lasts actions before a real engine run can be done and then followed by all kind of functional tests and then the usual tests before first flight.

Does anyone know what the main purpose of this flight test article is. Is it mostly for avionics or for other things?

WH002, will test auto-land, ground effects, stability and control
 
VV
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Re: Boeing 777X Testing/Production Thread - 2020

Sun Mar 01, 2020 12:04 pm

Can anyone say about the preliminary approach speed at the expected MLW?
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Mar 02, 2020 12:19 pm

Do we expect to see the 777X at the Farnborough Airshow now that testing is well underway?
 
LilD350
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Mar 02, 2020 3:01 pm

I think one of the reasons people might be wondering why the 777x never flew above 20000ft is that the A350, with all its new systems and design, flew at its maximum service altitude at around 43000ft on its second flight...
 
VV
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Mar 02, 2020 4:02 pm

LilD350 wrote:
I think one of the reasons people might be wondering why the 777x never flew above 20000ft is that the A350, with all its new systems and design, flew at its maximum service altitude at around 43000ft on its second flight...


Was it a useful test flight?
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Mar 02, 2020 4:03 pm

LilD350 wrote:
I think one of the reasons people might be wondering why the 777x never flew above 20000ft is that the A350, with all its new systems and design, flew at its maximum service altitude at around 43000ft on its second flight...

I think following the max incident and everything thats going with the current re-certification of it, Boeing is really focusing on the airplanes handling characteristics and how the controls perform in flight (with this first test frame). Like the chieft test pilot said they want to be ready as possible for the certification flights etc and they're taking what they've learnt from the max debacle
 
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Stitch
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Mar 02, 2020 4:26 pm

LilD350 wrote:
I think one of the reasons people might be wondering why the 777x never flew above 20000ft is that the A350, with all its new systems and design, flew at its maximum service altitude at around 43000ft on its second flight...


Airbus and Boeing might follow different flight test protocols so I think a more relevant metric would be how soon did the 787-8, the 737-8 and the 747-8 each reach maximum service altitude?
 
StTim
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Mar 02, 2020 4:41 pm

VV wrote:
LilD350 wrote:
I think one of the reasons people might be wondering why the 777x never flew above 20000ft is that the A350, with all its new systems and design, flew at its maximum service altitude at around 43000ft on its second flight...


Was it a useful test flight?


You think they did it for fun?

If I remember the early flights were all about opening up the flight envelope such that any future tests could be done at the optimum altitudes.

I did not follow the MAX or Neo and certainly the 787 flight testing was to early for me so I do not know if this just shows a difference in test planning between the two airframers.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Mar 02, 2020 4:46 pm

StTim wrote:
VV wrote:
LilD350 wrote:
I think one of the reasons people might be wondering why the 777x never flew above 20000ft is that the A350, with all its new systems and design, flew at its maximum service altitude at around 43000ft on its second flight...


Was it a useful test flight?


You think they did it for fun?

If I remember the early flights were all about opening up the flight envelope such that any future tests could be done at the optimum altitudes.

I did not follow the MAX or Neo and certainly the 787 flight testing was to early for me so I do not know if this just shows a difference in test planning between the two airframers.

Expansion of the flight envlope to max altitude for Boeing is usually after initial airwrothiness testing is complete. Given WH001 is in maintenance for the next week or so, i believe those tests should be complete now. but not 100% sure.
 
LilD350
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Mar 02, 2020 5:20 pm

Here's the link about the A350 flight details

https://youtu.be/Jzbpnfgpooc

Obviously both companies have different testing procedures so this envelope thing is a non issue...

Airbus definitely did a lot of the things the 777X is currently doing now, after their pilots finished having their fun.

What matters is the 777X has its own program checklists and they executing on it at the moment.

I guess a lot of us fanatics would have loved to see this plane flying full speed at max altitude and saving all that fuel with its new giant blowers
 
VV
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Mar 02, 2020 8:05 pm

LilD350 wrote:
...
What matters is the 777X has its own program checklists and they executing on it at the moment.
...


We know that the 777-9 is a long fuselage aircraft and thus the field performance is cruicial.

I think they know it and thus they test the "low-speed" performance and the corresponding flap configurations early in the process. It is much-much better to optimize and to freeze flap/slat angle settings early such that there are not "dev" flight test later on during the flight tests campaign.

More specifically they need to get the best possible approach speed in the two most used landing configurations.

We all know that the altitude with flaps extended is limited.

I do not have flightradar24 account, but I bet they are still doing roller-coaster flight profiles. If you have an account, can you please tell us if the speeds and altitudes of the early flights vary a lot.
 
Sooner787
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Mar 02, 2020 9:08 pm

Opus99 wrote:
Do we expect to see the 777X at the Farnborough Airshow now that testing is well underway?


I'd be surprised if it wasn't there...... I suspect an example in either LH or EK livery will be at the show
 
oschkosch
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Re: Boeing 777X Testing/Production Thread - 2020

Mon Mar 02, 2020 10:51 pm

Sooner787 wrote:
Opus99 wrote:
Do we expect to see the 777X at the Farnborough Airshow now that testing is well underway?


I'd be surprised if it wasn't there...... I suspect an example in either LH or EK livery will be at the show
someone with lh inside knowledge said on a german forum the other day that internal talk within lh is that they won't have the 777x until mid 2021, but no details were given.

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

Tue Mar 03, 2020 6:44 am

What's up with the second flight test article?
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Tue Mar 03, 2020 9:10 am

VV wrote:
What's up with the second flight test article?

last we heard it had another engine run on March 1
 
dagKentWA
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Re: Boeing 777X Testing/Production Thread - 2020

Tue Mar 03, 2020 4:05 pm

VV wrote:
LilD350 wrote:
...
What matters is the 777X has its own program checklists and they executing on it at the moment.
...


We know that the 777-9 is a long fuselage aircraft and thus the field performance is cruicial.

I think they know it and thus they test the "low-speed" performance and the corresponding flap configurations early in the process. It is much-much better to optimize and to freeze flap/slat angle settings early such that there are not "dev" flight test later on during the flight tests campaign.

More specifically they need to get the best possible approach speed in the two most used landing configurations.

We all know that the altitude with flaps extended is limited.

I do not have flightradar24 account, but I bet they are still doing roller-coaster flight profiles. If you have an account, can you please tell us if the speeds and altitudes of the early flights vary a lot.


I've been tracking the flights on flightaware.com, and I've seen a lot of exactly what you describe - up & down, faster & slower. They've also landed & taken off at Spokane (GEG) several times, which would make sense if they are looking for optimum landing speeds & configuration.

David
 
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Stitch
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Re: Boeing 777X Testing/Production Thread - 2020

Tue Mar 03, 2020 5:39 pm

The likelihood of the Restoring Aviation Accountability act being made law before the 777X receives her Type Certificate is extremely unlikely considering how slow Congress moves. And even if it is somehow enacted before the completion of the 777X's current certification, having read the text of the proposed Act, the timeframes involved for the implementation of the 18 member aircraft type certificate review panel the act calls for and the quinquennial certificate review cycle means that the 777X would receive her certificate under current regulations and that the Act would then come into effect five years on when the certificate is up for review (or sooner if Boeing files for a Supplemental or Amended Certificate).

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