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

Tue Feb 04, 2020 9:20 pm

scbriml wrote:
Aviator34ID wrote:
We are up to 4 flights now I think. Is anybody going to pick up the idea of tabulating flights/hours as the test program picks up speed?


Great idea. You should do it!


I'll have a go. I guess picking up history by rego on FR24 is the best way?
 
Aviator34ID
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Re: Boeing 777X Testing/Production Thread - 2020

Tue Feb 04, 2020 9:26 pm

So, first entry:

4 flights, 17.3 hrs, all B779XW.
I will try to do an update once or twice a week.
 
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seabosdca
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 3:30 am

That gear-up picture really puts the size of the wing in focus. That wing is absolutely enormous.
 
majano
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 9:18 am

Aviator34ID wrote:
So, first entry:

4 flights, 17.3 hrs, all B779XW.
I will try to do an update once or twice a week.

Thank you. I guess those who have a better method and / or access to information can add to your entries.
 
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RRUltrafan
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 1:12 pm

WIederling wrote:
RRUltrafan wrote:
It wouldn't exactly need it considering its supposed to fulfil the similar missions as the 77W, which aren't ULH flights. The 777-8x would benefit because of its mission requirements, but couldn't weight be saved on the -9x by simply reducing the fuel tank size?


There are no "tanks" that could be made smaller :-)

Remember the tank size increase on the A350? That was not much more than changing level cut offs when filling.

"Tank" is the wing volume available between main spars on the sides and wing skins ( top/bottom).
( some exclusions around engines, ... )

Add the center wing box.


Yeah the rearrangement of piping and MTOW raise to 280 tons. I was more or less referring to the center tank than the wing tanks though, if that could be decreased in size
"Everything has an end, but, only the sausage has two" - Albert Einstein
 
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RRUltrafan
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 1:13 pm

EIS is projected to be 2021 now or 2022 because I've seen some confusing things in the past few days?
"Everything has an end, but, only the sausage has two" - Albert Einstein
 
WIederling
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 1:23 pm

RRUltrafan wrote:
WIederling wrote:
Add the center wing box.


Yeah the rearrangement of piping and MTOW raise to 280 tons. I was more or less referring to the center tank than the wing tanks though, if that could be decreased in size


Center tank is the center wing box.
Center wing box size is fixed via width of the fuselage and attachment profile of the wings. a top and bottom curved brick.
Below the available volume adaptions are via filling level cutoff.
On the A350 some space in the wings is fluid wise part of the center tank. I've seen nothing on the 777 (X or not) arrangement

There is no additional integral tank space. Next step is some ACT or whatever you want to call it that is placed in the hold.
Murphy is an optimist
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 1:50 pm

RRUltrafan wrote:
EIS is projected to be 2021 now or 2022 because I've seen some confusing things in the past few days?

2021
 
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bikerthai
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 2:01 pm

So here's thought exercise.

Given that the center wing size is fixed by the fuselage configuration.

The sweep of the wing is fix to existing sweep (maybe a bad assumption).

The wing length (without winglet) is fixed to to the length of current 777.

And CFD and supercomputing have told you what series of airfoils to use for most efficient wing shape at cruise speed.

Then the length of the wing tip is pretty much predetermined depending how you want to terminate the tip. In this case a raked tip (also predetermined by CFD).

And assuming that efficiency in hardware design and placement would not impact the total wing volume that much, then the total fuel capacity in the wing would pretty much be what it is.

Not much else you can do to manipulate the capacity other than aux tanks.

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

Wed Feb 05, 2020 2:14 pm

From Wiki - it can carry a lot of fuel https://en.wikipedia.org/wiki/Boeing_777X

"The 777X has a new longer composite wing with folding wingtips.[64] Based on the 787 wing but with less sweep, the new wing has a higher lift-to-drag ratio, an aspect ratio increased from 9:1 to 10:1, an area increased from 4,702 to 5,562 sq ft (436.8 to 516.7 m2), and usable fuel capacity increased from 320,863 to 350,410 lb (145,541 to 158,943 kg).
 
744SPX
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 2:22 pm

Hmmm... wonder why the sweep is less. I'm assuming that the new wing is designed to bring cruise speed up to .85 mach from .84?

Also, this will be the first Boeing since the 747SP that has relatively low wing loading.
 
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bikerthai
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 2:50 pm

Less sweep than the 787? But how does it compare to the current 777?

More sweep = more speed, but less efficient.

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

Wed Feb 05, 2020 3:14 pm

Is the fuselage of 777x made out of Aluminum-Lithum? Or another type of alloy?
 
mjoelnir
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 3:45 pm

It depends also on the wing design. When the wing gets supercritical (laminar flow reaches further along the wing), it needs less sweep at a higher speed. So sweep equals speed is a bit to simple.
 
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bikerthai
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 4:51 pm

mjoelnir wrote:
So sweep equals speed is a bit to simple.


But in it's simplest term given everything else is equal, the statement is correct. :wink2:

That is why I was asking about the sweep compared to the original 777 wing. If the sweep is the same, then we probably can attribute the increase in speed to the airfoil shape, and to a very small extent, increase engine power and less wing drag due to fewer fasteners.

bt
Intelligent seeks knowledge. Enlightened seeks wisdom.
 
744SPX
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 5:57 pm

I'm going on the assumption that the 777X cruise speed will be .85 mach but I haven't been able to find any info from Boeing that gives an actual cruise speed. Maybe they are waiting to see how the new wing performs to make a decision. I recall B originally stated the 748 cruise speed would be .86 mach but lowered it to .855 later...
 
744SPX
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Re: Boeing 777X Testing/Production Thread - 2020

Wed Feb 05, 2020 5:59 pm

I also think the original 772 cruise speed was predicted to be .83 mach and they found it actually could do .84
 
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Stitch
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 06, 2020 1:21 am

Opus99 wrote:
Is the fuselage of 777x made out of Aluminum-Lithum? Or another type of alloy?


There was talk early on about using new Al or Al-Li alloys, but I believe the end decision was to stay with the existing Al alloy.
 
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CCA
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 06, 2020 4:05 am

The center TANK for the -300ER and -9 extends into the wing. The center wing box lower skin is slightly re profiled on the -9 (a few inches nothing drastic)

The -9 has basically kept the same SIZE/quantity main left and right tanks (10,300 vs 10,338 gal) by pushing the tank further outboard with the extra span available. This has allowed the center tank to extend further outboard. It now carries an extra 4,200 gal over the ER center tank.

The sweep is reduced from 31 degrees to 28, design speed the same at .84. (Increased lift for the same speed)

The wing area has increased from 4650sf to 5500sf (Increased lift for the same speed).

Same ER MTOW as mentioned earlier means less runway or slower takeoff speeds with the new wing.
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Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 06, 2020 7:25 am

Stitch wrote:
Opus99 wrote:
Is the fuselage of 777x made out of Aluminum-Lithum? Or another type of alloy?


There was talk early on about using new Al or Al-Li alloys, but I believe the end decision was to stay with the existing Al alloy.

I know al-li alloys were used for the cargo floors. But the rest I don’t know probably kept it the same
 
flipdewaf
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 06, 2020 10:39 am

CCA wrote:
The sweep is reduced from 31 degrees to 28, design speed the same at .84. (Increased lift for the same speed)

The wing area has increased from 4650sf to 5500sf (Increased lift for the same speed).

Sorry for being a pedant (who am I kidding, I love it) but if the lift is increasing I hope the FAA is ready to certify it for flying loops!

Fred
Image
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 06, 2020 12:45 pm

Just looked at today’s flight plan for BOE1 on flight aware and it seems that altitude is much higher today at 35000 feet. I believe this more in tune with air worthiness testing where the aircraft now begins to operate in more normal conditions
 
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bikerthai
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 06, 2020 1:15 pm

CCA wrote:
The sweep is reduced from 31 degrees to 28, design speed the same at .84. (


Good info. Give insight to what the designers were thinking.

Thanks

bt
Intelligent seeks knowledge. Enlightened seeks wisdom.
 
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747classic
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 06, 2020 6:14 pm

The latest Lufthansa B777-9 delivery planning (subject to change) :

D-ABTA, B777-9, L/N 1638, January 2021

D-ABTB, B777-9, L/N 1670, March 2021

D-ABTC, B777-9, L/N 1673, April 2021

D-ABTD, B777-9, L/N 1675, May 2021

D-ABTE, B777-9, L/N 1581, July 2021, Test aircraft #3 , N779XY

D-ABTF, B777-9, L/N 1681, September 2021

D-ABTG, B777-9, L/N 1686, October 2021

D-ABTH, B777-9, L/N 1691, March 2022

D-ABTI, B777-9, L/N 1587, August 2021, Test aircraft #4, N779XZ

See : https://sites.google.com/site/lhgroupfleet/lufthansa
Operating a twin over the ocean, you're always one engine failure from a total emergency.
 
MileHFL400
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 06, 2020 6:38 pm

Will there be a flight today?
Thanks and best Regards
AA
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 06, 2020 6:41 pm

MileHFL400 wrote:
Will there be a flight today?

One is currently scheduled. Whether it will actually happen is a different matter
 
SDL
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Re: Boeing 777X Testing/Production Thread - 2020

Thu Feb 06, 2020 6:46 pm

Hopefully it flies again today. I also hope number 2 is up in the air soon.
 
UAEflyer
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 6:31 am

747classic wrote:
The latest Lufthansa B777-9 delivery planning (subject to change) :

D-ABTA, B777-9, L/N 1638, January 2021

D-ABTB, B777-9, L/N 1670, March 2021

D-ABTC, B777-9, L/N 1673, April 2021

D-ABTD, B777-9, L/N 1675, May 2021

D-ABTE, B777-9, L/N 1581, July 2021, Test aircraft #3 , N779XY

D-ABTF, B777-9, L/N 1681, September 2021

D-ABTG, B777-9, L/N 1686, October 2021

D-ABTH, B777-9, L/N 1691, March 2022

D-ABTI, B777-9, L/N 1587, August 2021, Test aircraft #4, N779XZ

See : https://sites.google.com/site/lhgroupfleet/lufthansa


Is there a delivery plan for EK ?
 
Scotron12
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 6:55 am

I read that SQ will get their 1st 779 in 2022 and that NH order is 14...not 20, as previously disclosed.

Does Boeing have a order sheet by airline?
 
EK7777
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 8:29 am

I put this together, let me know if anyone wants anything specific to be added to it. It's very basic right now.

https://drive.google.com/open?id=1tlVU7 ... 0_GfzQnDhA
 
Aviator34ID
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 8:38 am

EK7777 wrote:
I put this together, let me know if anyone wants anything specific to be added to it. It's very basic right now.

https://drive.google.com/open?id=1tlVU7 ... 0_GfzQnDhA

I bow to your superior spreadsheet and will withdraw ;)
 
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Chipmunk1973
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 8:43 am

CCA wrote:
The sweep is reduced from 31 degrees to 28, design speed the same at .84. (Increased lift for the same speed)


I wonder why they didn’t want to pursue the slight speed increase to M0.85? When the 787 and 350 were launched, both manufacturers seemed to be making a bit of a song and dance about flying at .85.

Rgds,
C1973
Cheers,
C1973


B707, B717, B727, B734, B737, B738, B743, B77W, A300, A320, A332, A333, A339, A388, BAe146, Cessna 206.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 9:23 am

https://www.flightglobal.com/airframers ... 87.article

This should give a better idea of where the FAA stands on certification of the 777X. Especially on “grand fathering”. The last paragraph makes a note about if the aircraft is more software based than hardware based then that may cause them to certify it as a new type. Well at least that’s how I understood it. But it’s still very difficult to tell now
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 9:24 am

EK7777 wrote:
I put this together, let me know if anyone wants anything specific to be added to it. It's very basic right now.

https://drive.google.com/open?id=1tlVU7 ... 0_GfzQnDhA

Nice! Thanks for that
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 9:26 am

Scotron12 wrote:
I read that SQ will get their 1st 779 in 2022 and that NH order is 14...not 20, as previously disclosed.

Does Boeing have a order sheet by airline?

LH? It is 20 they have moved 14 from commitments to options but in Boeing’s order books they were always options. I believe it was more so for shareholder information really
 
Scotron12
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 10:19 am

Opus99 wrote:
Scotron12 wrote:
I read that SQ will get their 1st 779 in 2022 and that NH order is 14...not 20, as previously disclosed.

Does Boeing have a order sheet by airline?

LH? It is 20 they have moved 14 from commitments to options but in Boeing’s order books they were always options. I believe it was more so for shareholder information really


Thanks for reply...but NH ( ALL NIPPON ) not LH.


https://simpleflying.com/when-will-ana- ... eing-777x/

Says original order was 20 x 779s. Now is 14??
 
majano
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 10:24 am

EK7777 wrote:
I put this together, let me know if anyone wants anything specific to be added to it. It's very basic right now.

https://drive.google.com/open?id=1tlVU7 ... 0_GfzQnDhA

Very good indeed. Simple, but not simplistic.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 10:26 am

Scotron12 wrote:
Opus99 wrote:
Scotron12 wrote:
I read that SQ will get their 1st 779 in 2022 and that NH order is 14...not 20, as previously disclosed.

Does Boeing have a order sheet by airline?

LH? It is 20 they have moved 14 from commitments to options but in Boeing’s order books they were always options. I believe it was more so for shareholder information really


Thanks for reply...but NH ( ALL NIPPON ) not LH.


https://simpleflying.com/when-will-ana- ... eing-777x/

Says original order was 20 x 779s. Now is 14??

Simple flying has very unreliable articles full of errors
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 11:36 am

https://www.flightglobal.com/air-transp ... 88.article

Some more details on the flight test program
 
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bikerthai
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 2:26 pm

Chipmunk1973 wrote:
I wonder why they didn’t want to pursue the slight speed increase to M0.85


Needless to say, the answer is complex. But if you want to break it down to the simplest trade-off , it would be a balance between speed and range.

Optimizing the plane to fly at that higher speed would cost more fuel, thus less payloads and or range for the same weight.

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

Fri Feb 07, 2020 3:08 pm

Thats just nameplate. It might feasibly do . 85
 
highflier92660
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 3:32 pm

For everyone commenting on the projected cruise Mach of the 777X: Boeing seems to have deliberately withheld this information as if it were a closely-guarded national defense secret. My only guess is that it will be .85 like the A350-- unless Boeing unveils a marketing PR surprise and it becomes a highly-unlikely .86.
 
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Stitch
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 6:53 pm

Scotron12 wrote:
I read that SQ will get their 1st 779 in 2022 and that NH order is 14...not 20, as previously disclosed. Does Boeing have a order sheet by airline?


Yes you can do a User-Defined report on Boeing's Orders and Deliveries page.

As of 31 December 2019, ANA still has a 20 frame order for the 777X.
 
Opus99
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 7:49 pm

5th test flight happening now
 
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ER757
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 7:59 pm

Opus99 wrote:
5th test flight happening now

Flight plan indicates they'll be going higher and faster today
 
SDL
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 8:08 pm

Very slow att the moment but maybe higher and faster later

ER757 wrote:
Opus99 wrote:
5th test flight happening now

Flight plan indicates they'll be going higher and faster today
 
tomcat
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Re: Boeing 777X Testing/Production Thread - 2020

Fri Feb 07, 2020 8:09 pm

Chipmunk1973 wrote:
CCA wrote:
The sweep is reduced from 31 degrees to 28, design speed the same at .84. (Increased lift for the same speed)


I wonder why they didn’t want to pursue the slight speed increase to M0.85? When the 787 and 350 were launched, both manufacturers seemed to be making a bit of a song and dance about flying at .85.

Rgds,
C1973


As a reference, the wing sweep of the 787 and the A350 are 32.2 degrees and 31.9 degrees respectively while the A350 appears to cruise a tad faster than the 787. So with nearly 4 degrees less sweep, it's hard to imagine that the 777X would match the cruise speed of the A350. If I remember correctly, in the long Sunrise Project thread, Zeke hinted that the 777X cruise speed would be lower than the A350 one. That's the best info we can go by for now. Let's wait what the flight test campaign will deliver on that front.

I suspect that the MTOW limit inherited from the legacy 777 design must have lead to very interesting trade-offs in the area of the wing weight vs wing area vs cruise speed and possibly more design criteria's. I'm also wondering if the integration constrains of the folding wingtip and its associated structural requirements have imposed any challenge on the wing sweep.
 
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CCA
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Feb 08, 2020 2:41 am

Update from aero news (flight global)

Re remaining test aircraft which should fly before the 2nd qtr 2020.

https://aeronewsglobal.com/three-more-b ... rter-2020/

WH002 (N779XX) will test auto-land, ground effects, stability and control, while WH003 (N779XY) will test the auxiliary power unit, avionics, flight loads and propulsion performance. As for WH004 (N779XZ), it will be used to test the environmental control system, extended twin-engine operations, noise and general functionality and reliability.
Enthusiast
 
EK7777
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Feb 08, 2020 8:31 am

Max altitude was still around 20k ft, but ground spd was up to 450 kts for this flight.
 
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bikerthai
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Re: Boeing 777X Testing/Production Thread - 2020

Sat Feb 08, 2020 2:58 pm

tomcat wrote:
I'm also wondering if the integration constrains of the folding wingtip and its associated structural requirements have imposed any challenge on the wing sweep.


Yah. The greater the sweep, the greater the difference between the angle of the ribs and the folding hinge line. Make for less efficient structure.

The other difference between the 787, A350 and the 777 is that the 777 fuselage shear and stringers are still fastened, giving it a slightly higher drag coefficient. Not much in the grand scheme of thing, but in it's small way would impact the cruise speed

The composite frame may still have fasteners for the shear ties and stringers, but they may be for failed safe purpose only and there would be a lot fewer.

bt
Intelligent seeks knowledge. Enlightened seeks wisdom.

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