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SEPilot
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 7:01 am

Quoting Scbriml (Reply 49):
.

Wasn't this "myth" largely debunked in a recent thread?

What myth? What I was trying to say was pretty much what you said; I did forget that some of the hoops were titanium. I am fully aware that they are fastened in place; I'm sorry that I wasn't clear about that. Perhaps I didn't understand fully what SLz396 was saying; I understood what he said to mean that there was a complete frame that the barrels fitted over. I think we all are saying basically the same thing but interpreting each other differently.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
elvis777
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 7:08 am

Howdy all,

Hope this helps:

"Keeping the Barrel Rolling" or "Despite Big Qatar Buy, Airbus Faces A350XWB Design Debate"
Aviation Week & Space Technology
06/04/2007, page 40

Jens Flottau
Frankfurt

".......But after visiting the Boeing 787 final assembly line, Emirates President Tim Clark said that "fuselage barrels are the way forward. That's not to say that the Airbus approach is flawed, but I'm of the opinion that it represents an interim step and they will move to the barrel approach eventually.........


..........While Boeing is burning entire barrel sections in one piece in huge autoclaves, Airbus has selected what seems to be a more conservative approach: using smaller composite panels that are bolted on to aluminum frames, a construction method that does not differ much in principle from the way metallic airplanes are built......

.......Industry officials are concerned that Airbus may not be able to reach the same kind of maintenance cost reductions for the A350XWB that Boeing is promising for the 787 simply because the fuselage is made of more pieces and joints that have to be maintained. "[Airbus] must be watching Seattle very closely," Clark says........

.......as only a few companies in the world are technologically capable of building composite barrels in the sizes needed--and even Airbus is not one of them......

.........To make matters even more complex, the Power8 turnaround program is based on outsourcing more essential work such as fuselage parts, but the demanding job of burning barrels would possibly lead to more in-house work, making the restructuring goals harder to achieve. On the other hand, the A350XWB serves as the technological base for future Airbus aircraft programs and a wrong decision now could lead to implications beyond the A350 program....."

There is more of course.

Peace

Elvis777
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elvis777
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 7:19 am

Howdy all,

Some quick thoughts...

Quoting Elvis777 (Reply 51):
".......But after visiting the Boeing 787 final assembly line, Emirates President Tim Clark said that "fuselage barrels are the way forward. That's not to say that the Airbus approach is flawed, but I'm of the opinion that it represents an interim step and they will move to the barrel approach eventually.........

Several a.net members (Manni comes to mind) have placed a great deal of emphasis to the comments made by Mr. Tim Clark concerning certain EADS products. Namely that the 380 whalejet is a stellar perfomer (I am paraphrasing) and that it is a world beater/changer (again paraphrasing since I did not bother to look for the actual quote - but you get the idea). These A.net members have then gone on as if these vindicated the performance of the 380 and the issue was then settled. That is to say it must be at least meeting all design objectives and is probably beating them. I personally thought it was all talk but hey if other people bought into it then ok. But by the same token then his words on thsi product MUST be taken as the unvarnished truth!! And so if one reads between the lines he prefers barresl to panels!

Which means that all this discussion that has been going on on this thread is for naught as the ones claiming that panesl are equivalent or better to barrels are dead wrong!

Either the 380 stellar performance, world changer/beater is not really true or if it is then barrels are better than panels.

Peace

Elvis777
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CaptSkibi
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 7:32 am

Quoting Dvautier (Reply 8):
I think they are waiting for the Paris Air Show to announce a new and radically improved concept for the A350—barrels!

If this is the case, would they have to rename the A350XWB to something like A350XWBBAF for Barrel Airplane Fuselage?  Wink
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Ruscoe
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 7:36 am

Quoting Trent900 (Reply 17):
Do you really think Airbus will build an aircraft not as good as the 787? I don't think so. What would be the point?

I think you make the best point. This goes to the heart of what worries people about the 350.

That is given all the recent history at Airbus, can we be confident they will get it right?

They probably will and already have, but the niggling doubts in "buyers" minds are affecting 350 sales imo.

Ruscoe
 
slz396
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 7:42 am

Quoting Elvis777 (Reply 52):
Either the 380 stellar performance, world changer/beater is not really true or if it is then barrels are better than panels.

You are aware you are now assuming Mr. Clark to be always right, do you?

He could be wrong on the A380 and right on the A350, or the other way round too you know...

As an airline CEO, I'd say he's more qualified to judge the economic merits of a plane which has done route proving flights than the technical merrits of a design which hasn't even left the ground yet, so I do tend to rate his assesment of the A380 higher than his technical appreciation of the 787 vs the A350.

Regardless of that: if the overall operating cost of the A350 are lower then those of the 787 I am sure he won't mind ordering it just as he has done repeatedly with the A380, despite it not having a composite barrel fuselage...

[Edited 2007-06-05 00:46:46]
 
TeamAmerica
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 7:52 am

Quoting Slz396 (Reply 38):
Obviously there are no longitudinal joints to be found on the 787 as there will be on the A350, since the composite sections of the fuselage are spun in one piece iso made up of 4 shells like on the A350, however in return, there are a lot more circumferencial joints needed on the 787 than on the A350 as the length of the barrels used to make the fuselage of the 787 is shorter than on the fuselage segments of the A350.

This has been covered several times in previous threads. The total length of the joints on the B787 is much less than those for the A350 - that point is not debatable. What remains to be known is whether the greater expanse of joints on the A350 make any real difference in the performance or operating costs of the aircraft.

Quoting Scbriml (Reply 49):
most are composite, but I believe some are titanium

The splice plates are titanium, but I'm not aware of any titanium frames (or "hoops"). Since several posters have said there are some, perhaps someone could be more specific as to where they are located (and why titanium is required).

The material used for the frames is much more important than the barrels vs. panels question. Considering the maintenance cost comparison of the two aircraft, the use of metal frames rather than composites appears to be a liability for Airbus. I have yet to see a definite explanation as to why they are doing this. scratchchin 
Failure is not an option; it's an outcome.
 
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scbriml
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 8:00 am

Quoting Elvis777 (Reply 51):
That's not to say that the Airbus approach is flawed,

So he says it's not a problem.

Quote:
I'm of the opinion that it represents an interim step and they will move to the barrel approach eventually.........

Which might well be on Airbus's next plane, not necessarily the A350. Clark gives no timescale or even if he's talking about the same plane.

Quoting Elvis777 (Reply 52):
Which means that all this discussion that has been going on on this thread is for naught as the ones claiming that panesl are equivalent or better to barrels are dead wrong!

Hardly, because neither approach has yet been proven where it matters. In daily airline service.
Time flies like an arrow. Fruit flies like a banana!
There are 10 types of people in the World - those that understand binary and those that don't.
 
CJAContinental
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 8:02 am

Quoting Elvis777 (Reply 52):

As impressive an airline as emirates is, much due to clarks contributions and a lot of money from the royals that own the airline, could it not be such that even a man you claim as omniscient as him can sometimes be full of ****.

You see, its what he prefers, and even though he can be claimed as a somewhat reliable role-model to the rest of the industry, it doesn't mean that his opinionated thoughts are the definate facts;

Is the A380 a wonderful gift from above for an airline like emirates, probably.
Ask the same for some japanese airline perhaps, and the answer is likely no.

Having said that, your point concerning the 787 barrel design is valid, and generally, yeah I think Clark is in a decent position to judge, I don't think he's going to be biased in any way, and he'll certainly want to do whats best for emirates.
I also agree that the barrel design is certainly the safest bet, purely because as mentioned before, CFCP barrels are not easy to come by (not many companies can make them), and thus boeing's convenience could be increased by using panels. However, boeing's priorities, particularly on the 787 are efficiency and longevity, and thus they'll go along with the mild inconvenience to make their plane better, proving their large faith in the barrel design. After lots of tests and ideas on construction, I'm sure over the recent years in designing the 787, time has allowed them to make the most correct decisions; I wouldn't say they've exactlt been rushed.

[Edited 2007-06-05 01:07:59]
Work Hard/Fly Right.
 
Wsp
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 8:04 am

Quoting TeamAmerica (Reply 56):
The total length of the joints on the B787 is much less than those for the A350 - that point is not debatable.

Do the 787-8/9/10 have all the same number of sections just with different lengths or different numbers of sections?
Willl the A350XWB--800/900/1000 have all the same number of sections just with different lengths or different numbers of sections?
 
aminobwana
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 8:13 am

Quoting Teva (Reply 12):
Not using the same technology doesn't mean using outdated technology. It just means taking a different approach.
future will tell which direction is the best.
If the A350 meets the expectations, for the price announced, I don't see why airlines wouldn't buy it.



Quoting EI321 (Reply 21):
At the end of the day, it comes down to operating costs. Both with the 737/A320 and with the 787/A350. Unless the 787 has lower operating costs then the Barrel argument is a superficial one.



Quoting MCIGuy (Reply 11):
One of the things that was drummed into my head while working for big business is that "perception is everything".

As as far I understand, the some of the main advantages of the barrel construction are fatigue and maintenance related, nobody really will know at delivery of the A350s if they meet expectations or not !!
Neither will the operating cost be known, if these include the maintenance.

Therefore, as MCIGuy says, if people buys it or not will depend of the perception !!

An example: As I also worked for big business, during many years, especially in Latinamerica, US firms sold E-Motors which were heavier than the equivalent German.
The US motors were more expensive, but due to the perceived "more solid" construction, customer thought that they are more reliable (which were objectively mistaken) and so, for years, they prevailed !!

From the article in reply 0:
1)

Quote:
Airbus said it would manufacture 13 A350s a month by the third year of production, 2016, representing its highest production rate for a wide-body aircraft

This is really funny: BOEING with nearly 600 B787 orders and new ones raining in, and with all the funding available as needed, is very careful not to mislead customers by promising production increases which eventually would not be implemented, mainly because the risk to build up a too high capacity, but Airbus, with at the moment nearly no firm orders and in financial distress, announces the "highest production for a wide-body". 13 a months, in the third year of production !!!
I cannot imagine customers being comfortable with delivery slots basing on such !!!

2)

Quote:
Airbus is cutting 10,000 jobs and streamlining a fragmented production process spread across four European member countries -- France, Germany, Britain and Spain -- but denies that the use of panels is designed to preserve the separation of tasks between individual plants

This reason, even if denied, is only one of several. SEPilot, Reply 19, has named a number of these,

aminobwana
 
brendows
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 8:18 am

Quoting Wsp (Reply 59):
Do the 787-8/9/10 have all the same number of sections just with different lengths or different numbers of sections?

Some sections will be longer on the longer versions. The sections that will be extended is section 43 and 46, the section just forward of the wing, and the first section behind the wing and wheel well.
 
TeamAmerica
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 8:19 am

Quoting Wsp (Reply 59):
Do the 787-8/9/10 have all the same number of sections just with different lengths or different numbers of sections?
Willl the A350XWB--800/900/1000 have all the same number of sections just with different lengths or different numbers of sections?

The B787 will be stretched with longer sections. I expect the A350 will be similar, using longer panels.

That does raise a point - the stretched B787's will have no additional length of joints, but stretching the XWB means lengthened longitudinal joints. It's a small difference, but as the airframes are stretched it would appear that the advantage of the barrel approach is amplified.
Failure is not an option; it's an outcome.
 
elvis777
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 8:37 am

Howdy SLZ396,

Quoting Slz396 (Reply 55):
You are aware you are now assuming Mr. Clark to be always right, do you?

He could be wrong on the A380 and right on the A350, or the other way round too you know...

You hit the nail in the head. I am not claiming either actually . I simply wanted to ensure that whatever Mr. Clark says should be taken with a grain of salt. He is not the burning bush and so whatever comments he makes should as definitive proof or a concept/idea. So yeas I know full well that what he says on a certain day might be colored by the longitude of his location (for example) but are you aware of the same? Are others?

Quoting Slz396 (Reply 55):
As an airline CEO, I'd say he's more qualified to judge the economic merits of a plane which has done route proving flights than the technical merits of a design which hasn't even left the ground yet, so I do tend to rate his assessment of the A380 higher than his technical appreciation of the 787 vs the A350.

Now you are trying to find a loophole around your first point! And your position is one way to go but there are others that I dare say have equal weight (he was bored and was speaking to an EADS/Boeing crowd... Or what ever). So if we can agree that all of his comments should not be constituted as pure truth when it applies to any bird and that his comments may be colored temporarily for unknown reasons and that we should not promulgate his words as either resounding validation nor resounding repudiation then I can live with that. Easily, actually.

So in that vein I can say that based on his comments the 380 whalejet (is / is not) a "STELLAR" bird and with the same color pen I can say that the 350 v3 (is / is not) up to par with the 787.

I can easily live with the above. But can everyone else live with this?

Quoting Slz396 (Reply 55):
Regardless of that: if the overall operating cost of the A350 are lower then those of the 787 I am sure he won't mind ordering it just as he has done repeatedly with the A380, despite it not having a composite barrel fuselage...

Here we are somewhat of an agreement. IF the 350v3 has better economics for his particular routes than the 787 then he will probably order it. The trouble is that the 2 birds are not necessarily competing in the same market and on top of that there is the pesky issue of maintenance costs.... But I can easily live with your last statement. It appears that the 380 is meeting HIS requirements. So he is ordering a lot. No one said there were not going to be any orders. Just that there were not going to be ENOUGH to make a profit....

But back to the 350/787 issue. If things go as they now appear to go (panels instead of barrels, 350 competes against 777 instead of 787) then I am very very happy. We (boeing) can live with this. The 787 will remain free of competition and IF we are RIGHT barrels are better than panels then a replacement for the 777 (which we can do faster than you can build the 350- I think ist 4 years to your 6) will do quite well against the 350. So in MY own humle and personal opinion I hope that eads goes ahead as they are right now. We can live with that. Perhaps not easily but maybe......

Ok., thanks for your kind response SLZ396.

Regards and of course peace

Elvis777
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Wsp
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 8:47 am

Thanks Brendows and TeamAmerica for the clarification.

Quoting TeamAmerica (Reply 62):
but stretching the XWB means lengthened longitudinal joints

Yes. Although Airbus insists that these joints carry much lower loads than the barrel joints. So their argument is that joint doesn't equal joint in the two scenarios.

Quoting Aminobwana (Reply 60):
13 a months, in the third year of production

Where in particular do you see the failure points in Airbus' production ramp-up ?
 
elvis777
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 8:50 am

Howdy Scrbiml

Quoting Scbriml (Reply 57):
Quoting Elvis777 (Reply 51):
That's not to say that the Airbus approach is flawed,

So he says it's not a problem.

I don�t agree with your understanding of the piece. I believe that he is being cautious in his repudiation of the panel approach. If you couple this statement with the others attributed to him in the SAME piece then I dare say that his point of view is that panels are an interim solution that is inferior to a barrel solution. You are of course free to your own interpretation and so god bless. But as I said earlier I do not agree with your take on this.

Quoting Scbriml (Reply 57):
Quote:
I'm of the opinion that it represents an interim step and they will move to the barrel approach eventually.........

Which might well be on Airbus's next plane, not necessarily the A350. Clark gives no timescale or even if he's talking about the same plane.

Again differences in interpretation. I do believe he is talking about the 350 AND the next generation of eads airliners. I believe he is stating in no unclear terms that a panel approach is not the best way to go. But you are of course welcome to read it differently.

Quoting Scbriml (Reply 57):
Quoting Elvis777 (Reply 52):
Which means that all this discussion that has been going on this thread is for naught as the ones claiming that panels are equivalent or better to barrels are dead wrong!

Hardly, because neither approach has yet been proven where it matters. In daily airline service.

No, I think I was not clear or you misunderstood. IF we base the solution SOLELY on the basis of Mr. T. Carks argument then we have a few options. Either all he says is true. In which case the 380 whalejet is a stellar performer that will be a world beater AND the 350 v3 panel approach is INFERIOR to the barrel approach.

However if we decide to not trust entirely his comments as they may be colored by whatever happened between him and his wife (or what have you) then we can continue this argument as it has not been settled. That is fine by me. So long as we then accept that we do NOT take his statements on the 380 as pure truth.

That is all I was trying to say.

But, in my opinion One which is based on my (semi) informed view I like the 787 , y3s chances against whatever eads can come up with. I like them a lot actually. I think that the 350v3 panel approach is good for Boeing.

As I cant type much you can see my previous post responding to SLZ's post if you want more...

Regards and as always.. Peace

Elvis777
Leper,Unevolved, Misplaced and Unrepentant SportsFanatic and a ZOMBIE as well
 
elvis777
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 8:59 am

Howdy CJAContinental,

Quoting CJAContinental (Reply 58):
Quoting Elvis777 (Reply 52):

As impressive an airline as emirates is, much due to clarks contributions and a lot of money from the royals that own the airline, could it not be such that even a man you claim as omniscient as him can sometimes be full of ****.

You see, its what he prefers, and even though he can be claimed as a somewhat reliable role-model to the rest of the industry, it doesn't mean that his opinionated thoughts are the definate facts;

EXACTLY!!!!!!!!! This is what I was trying to say. So his comments can/cannot be taken as those coming from the burning bush!!!! We should take ALL of them with a grain of salt or at face value. But WE SHOULD NOT pick and choose!! I hope you understand what I was trying to say. I think you hopefully clarified it for the others..

Quoting CJAContinental (Reply 58):

Is the A380 a wonderful gift from above for an airline like emirates, probably.
Ask the same for some japanese airline perhaps, and the answer is likely no.

I agree. No one ever claimed the whalejet would not sell one single frame. Just that it would not sell enough! Please see my responses to SLZ and Scribml for a bit more of my thoughts if you want.

Quoting CJAContinental (Reply 58):
Having said that, your point concerning the 787 barrel design is valid, and generally, yeah I think Clark is in a decent position to judge, I don't think he's going to be biased in any way, and he'll certainly want to do what�s best for emirates.
I also agree that the barrel design is certainly the safest bet, purely because as mentioned before, CFCP barrels are not easy to come by (not many companies can make them), and thus boeing's convenience could be increased by using panels. However, boeing's priorities, particularly on the 787 are efficiency and longevity, and thus they'll go along with the mild inconvenience to make their plane better, proving their large faith in the barrel design. After lots of tests and ideas on construction, I'm sure over the recent years in designing the 787, time has allowed them to make the most correct decisions; I wouldn't say they've exactlt been rushed.

Maybe you are right. Like I said Earlier. I really like our (Boeing) chances on this. The 350v3, in MY opinion, if built with panels and at the present size will not compete well with the 787. It will compete well with the 777 but it is also ripe for beating as we (boeing) can come up with a replacement to the 777 faster than eads can come up with a solution (4 or with a bit of luck 3 years for us 6 years for eads). Yeah I really hope that eads uses panels and maintains the same dimensions that have been thrown around. I really like our chances!

Regards and Peace

Elvis777
Leper,Unevolved, Misplaced and Unrepentant SportsFanatic and a ZOMBIE as well
 
flydreamliner
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 9:12 am

Quoting Sphealey (Reply 34):
> Now if the damage cuts the load path at any spot,
> how will you do a field repair?

What we don't know, and what Boeing isn't going to tell us, is what it takes to "cut the load path". The only publicly-documented large-scale composite barrel accident involved a Beech Starship runway overrun. The result was a number of navigational aids, vehicles, and hanger walls demolished but zero damage to the Starship's fuselage.

Now I would guess that since the Starship was a much small diameter than the 787 will be it was stronger per unit size. And it may have been over-engineered more than a commercial airliner will be. But the question is still there: with what force does the catering truck have to hit the 787 barrel to cause any damage? And again Boeing isn't going to tell us.

sPh

I guess you must have discovered Boeing's evil conspiracy. If you hit the 787 with something, you'll just have to buy a new one. Disposable airplanes!

Perhaps the FAA should require Boeing ram the 787 with a catering truck to prove it can survive.
"Let the world change you, and you can change the world"
 
sphealey
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 9:38 am

> Perhaps the FAA should require Boeing ram the 787 with a
> catering truck to prove it can survive.

I suspect the customers have already asked to witness that test (with the prototype barrel of course).

sPh
 
ncelhr
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 9:43 am

Okay, so here's the secret: Boeing's barrel composite design for the 787 is such that it is as strong as a "black box".
Hit it with a catering truck, it won't even have a scratch. No scratch = no repairs. Problem solved...
 Smile
 
cygnuschicago
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 10:05 am

Quoting Elvis777 (Reply 63):
So in that vein I can say that based on his comments the 380 whalejet (is / is not) a "STELLAR" bird and with the same color pen I can say that the 350 v3 (is / is not) up to par with the 787.

At the end of the day what matters is what he does with his money. Your argument that it is "both or neither", is in my opinion simply a straw man.

His comments on the A380 are based on actual, verifiable flight data. He has the opportunity to vote with his feet and dump the A380 - either some or all of them - and he didn't. He voted in favor of the A380 with his check book.

His comments on the 787 vs. A350 are firstly directed at the technology solution, not the actual plane, as far as I can tell. Secondly, the A350 has not yet reached design freeze. Thirdly he has not yet voted with his check book and put money on the 787.

You may be right, maybe the A350 is an inferior aircraft, but you'll only know his true opinion when he reaches for his check book and writes a fat check for either 787s or A350s.
If you cannot do the math, your opinion means squat!
 
pygmalion
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 10:14 am

Quoting Wsp (Reply 64):
Yes. Although Airbus insists that these joints carry much lower loads than the barrel joints. So their argument is that joint doesn't equal joint in the two scenarios.

If Airbus actually said this they should be sued for lying. I don't think that they did. This is wishful thinking. All engineers know that in a pressure vessel the longitudinal joints fatigue faster than the circumferential ones. Have you ever seen a formed beer can burst? The sides split, the ends don't come off. This can be also be seen by looking at ANY all-aluminum aircraft and reviewing the maintenance review book required to be published at delivery. It outlines the inspection requirements for all joints at given intervals for keeping the aircraft flight worthy. Lap longitudinal joints are much more highly loaded than the circumferential joints. This reduces the fatigue life and reduces the time interval between inspections. Current major inspection interval (D check) for the 787 is 12 years IIRC. Unless Airbus greatly increases the material thicknesses to reduce the stress levels in the lap joints, there is no way they will be able to get a 12 year period between inspections on the laps. Just the bolt bending stresses in the fasteners will drive reduced intervals. These inspections require the removal of the interior to expose both the inside and outside of the joint. Not cheap.

Joint doesn't equal joint... Hoop loads on longitudinal joints is much higher.

Maintenance costs (read as inspection costs) will be much higher for an airplane with longitudinal joints. Going full barrel sections is one of the major reasons that the 787 has such reduced maintenance.
 
Dougloid
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 10:41 am

Gurls, gurls....haven't we had this discussion enough?

All I've got to add to it is that there is the issue of timing and expense here.

Airbus has decided to go for panels and frames rather than monolithic CFRP fuselage structure. Fine.

It's possible that this decision was made because they don't think there's an advantage to be gained from monolithic construction. Or that there is but they don't want to pay for it.

It's possible that they looked at the entire idea askance because it's NIH-not invented here. That's something to consider.

It's possible that because of the drain on resources that the A380 has represented, Airbus can't afford the infrastructure and technology to do it right now. They're tackling three major development projects at one schwack. That's a lot to tackle, any way you look at it.

It's also possible that they looked at the idea of monolithic CFRP construction and said "two more years until EIS-we just can't afford to sit on our asses and make no money until 2015 instead of 2013. We've got to sell some damn planes."

There may be even more possibilities.

Fact is, none of us really know what the reason is and whether it matters. It's all speculation and guesswork at this point.

But timing is different.

Airbus are set to plant their A350 design in concrete in fall, 2008 and go forward from there with the parameters of the design essentially fixed. Perhaps they will have some idea of how well the idea worked out on the B787 from flight test data and preliminary operator's reports. But they will be committed to a course of action without knowing what minolithic CFRP construction holds for maintainability and durability, long term.

That's really where the big gamble is. If monolithic CFRP construction yields no great benefit over conventional structure or 'black aluminum', then Airbus gets to laugh at Boeing and rake in the dough.

On the other hand, if Boeing's bet pays a big enough dividend, then the A350 structural method is a technological dead end. And if THAT happens, they're screwed good and proper.

It is my own opinion that monolithic CFRP construction represents a revolution in aircraft methods and manufacturing that has not been seen since the 1930s when monocoque aluminum construction methods made dope and fab, fab over steel tubing, plywood, and corrugated aluminum over framework construction methods obsolete in about five years.

But that's my opinion. Your mileage may vary.
If you believe in coincidence, you haven't looked close enough-Joe Leaphorn
 
elvis777
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 10:47 am

Howdy CygnusChicago,

Quoting CygnusChicago (Reply 70):
At the end of the day what matters is what he does with his money. Your argument that it is "both or neither", is in my opinion simply a straw man.

His comments on the A380 are based on actual, verifiable flight data. He has the opportunity to vote with his feet and dump the A380 - either some or all of them - and he didn't. He voted in favor of the A380 with his check book.

I think your straw man argument is actually not a very good one. I agree that at the end of the day the mighty buck rules but the main argument is that his statements are NOT totally true or false. I dont think you understood. His statements should, in my opinion, be taken for what they are. Those made by an interested party out to fend only for his own interests. So then any comment regardless of praise or repudiation should not be waved as the spoken truth of Jesus Christ! He voted in favor of the whalejet but both you and I are unaware of any (if any at all) conditions that were given to him. Perhaps he paid FULL price or perhaps he got them fro free. What we can say is that for his airline the eads package made sense. I can live with that.

However waving his "stellar" comments as total vindication of the 380 program is where the trouble starts. In HIS opinion and for HIS airline the whalejet made financial sense. Ok., no big deal. It DOES NOT mean that it will make sense to any other airline (although it may!). So my beef is simply with this. Quite simple actually.

I for one am not taking his comments about the panel approach as being inferior as the gospel. Like I said he may have gotten lucky with a flight attendant for all I know, but his comments were probably colored. I do believe that the panel approach is inferior. But my belief is based on other data, not on mr Clark's comments. So I will NOT wave his comments around at people and say that the 350v3 is inferior to the 787 because the mountain has spoken. Although, on a personal note I do happen to believe that the panel approach is inferior to barrels and I really really hope that Eads stays the course if you would!

See what I mean? His comments are not the gospel. That is it. His purchasing of the whalejet does NOT vindicate the 380 program. If he were to purchase the 787 it would not vindicate the barrel over the panel apporach. Although if enough guys go one way or then one can start to see the light! Nothing strawish about it!

I dont know what data he has been given. You probably dont as well. One could argue that the verifiable data you claim he has is not really verifiable as the flight conditions were/were not the same as what he is going to fly. I dont knwo and I dont wish to make that argument. Lets jsut say that he sees the wrold with SELFISH colored glasses and so his comments SHOULD NOT be taken as the pure unvarnished truth whether ist pro/anti eads/boeing!

Quoting CygnusChicago (Reply 70):
His comments on the 787 vs. A350 are firstly directed at the technology solution, not the actual plane, as far as I can tell. Secondly, the A350 has not yet reached design freeze. Thirdly he has not yet voted with his check book and put money on the 787.

Your interpretation. Not mine. On one hand you claim that he has actual flight data on the 380 yet you understimate the data given to him by boeing. Data, with its inherent uncertainties, on a non production airplane that may/may not have been fitted differently then what he is planning on flying is just as good as an aerodynamic flight model- with its own uncertainties as well!

So what I see is that you and SLZ are trying to put more weight on certain of his comments and dismiss others because it goes against what you hope/believe/expect!

Why use the canard that the 350v3 is not yet finalized and so we should cut it some slack and yet the 787 which is almost built we should not trust it? If we are going on faith alone then I think we should give equal weight to the aerodyanmicists/engineers at boeing that are predicting a superior bird from their camp.

if we are to play the game of the checkbook we can say that he is the smartest man in the world but that all other airline executives surpass Mr. clarks intelligence and so since quite a few have voted with their checkbook then the 787, regardless of what the 350 looks like, is a superior solution!

But I hate that game b/c life is much more complicated than that. You come up with an example I come up with a counter example. Kind of high school ish...

So lets say then that my 'straw man' argument that all his comments should be taken with a bit of consideration and not taken as the gospel regardless if they are pro/anti eads/boeing is really the way to go!!!!

Quoting CygnusChicago (Reply 70):
You may be right, maybe the A350 is an inferior aircraft, but you'll only know his true opinion when he reaches for his check book and writes a fat check for either 787s or A350s.

At the end of the day the might buck rules. Fair enough. But maybe not. according to others (keesje) life is more complicated and often then not the 'best man' does not win..... Nah.. that is a bogus argument. More often than not the best man indeed does win. So the might buck does rule and I like our chances. I hope eads stays the course. I really, Really do. If you read my previous responses you'll see why I believe as I do!

Regards and Peace

Elvis7777
Leper,Unevolved, Misplaced and Unrepentant SportsFanatic and a ZOMBIE as well
 
ua76heavy
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 1:05 pm

Quoting SEPilot (Reply 19):
I suspect that this was a management decision based on time and money; Airbus knows how to build panels and probably does not need to invest in any major equipment to do so, or spend a lot of time developing the processes.

I agree. My understanding of the manufacture of composite components is that it requires a lot of expertise (tacit knowledge) gained through years of experience, especially "baking" parts/components in an autoclave, let alone a large fuselage barrel. Airbus doesn't have the luxury in time to gain this engineering and manufacturing expertise and perhaps does not have the resources to acquire it due to the A380. Also, I imagine the contractors working with Boeing have an exclusivity clause in their contracts which prevents Airbus from having access to this knowledge (and rightfully so since there is a lot of proprietary knowledge involved). Composite panels represent a quick solution, but the aircraft doesn't benefit from the manufacturing and maintenance benefits of a composite barrel (there's still a frame and rivets).
 
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zeke
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 1:33 pm

Quoting CJAContinental (Reply 22):
The only disadvantage that I can really see with this is that surely the panels will have to include the use of rivets and such. If I recall correctly, a saving of 1.5% can be saved on fuel on the 787 as it is free from microdrag caused by rivets and whatever else they'll apply them on with, which is significant in terms of the flights the 787 will be making, and the longevity of a 787's life?

The 787 does use fasteners.



Quoting ContnlEliteCMH (Reply 46):
I haven't seen the hoops in any photographs of the barrels. It looks to me like only the stringers are part of the CFRP monolith, and that frames are added later. Heck, in the photographs floating around on the web, the frames look like metal!

The inner hoops are not all the same.


Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
Oroka
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 1:38 pm

Well, at this rate Boeing will have a 777NG or 777 replacement out to deal with the A350. I can understand Airbus wanting to build the right plane that customers want... but customers will not want the A350 if they already ordered 787s cause A cant make up thier mind and start building the darn plane.
 
iwok
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 1:42 pm

Quoting T773ER (Thread starter):
But Gordon McConnell, chief engineer for the A350, said Airbus was sticking with plans to build the jet out of frames made of similar lightweight composite materials."

What are they doing for the A400?? Why not do the same thing?  confused 

iwok
 
dank
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 1:53 pm

Quoting Iwok (Reply 77):
What are they doing for the A400?? Why not do the same thing?   

iwok

from http://www.machinedesign.com/ASP/str...te/MDSite/viewSelectedArticle.asp:

"The fuselage is a conventional monocoque, but to maximize cargo volume, the cross section is not a true circle. Primary support structures, such as the skin, stringers, and frames, are aluminum. But titanium alloys are used in highly loaded areas such as around the windscreen, the wing-to-fuselage attachment, and around the landing gear. Lightly loaded areas, such as the fairings, use glass or carbon-reinforced composites. The fuselage maintains 8,000-ft cabin pressure when flying at 37,000 ft, and for high-altitude missions, it will keep 9,000-ft pressure at altitudes up to 40,000 ft. For medical evacuations or other sensitive cargo, the plane can maintain sea-level pressure up to 19,400 ft.

The wing makes extensive use of composites, technology Airbus learned making civil airliners. The wings use a front and rear composite spar, giving them a wide wing box and a significant amount of volume for carrying fuel. The left and right sides of the wing have an outboard aileron, five spoilers used for roll control, speedbraking, and lift dumping, and inner and outer fixed-vane flaps. All are made of carbon-fiber composites for a high strength-to-weight ratio.

Composites are also used for the wing skin, stringers, and spars, but metal is needed for the ribs, leasing edges, engine mountings, and fuselage pick-ups."

cheers.
 
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zeke
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 2:16 pm

Quoting UA76Heavy (Reply 74):
I agree. My understanding of the manufacture of composite components is that it requires a lot of expertise (tacit knowledge) gained through years of experience, especially "baking" parts/components in an autoclave, let alone a large fuselage barrel.

Airbus has been involved with a number of research projects that have produced full composite barrels (TANGO, FUBACOMP), and have been presenting papers on the subject for at least the last 5-10 years, some of this work is a referenced source used by Boeing with some of their patents.

Airbus has a lot of expertise and knowledge with composites, more than people give them credit for, please see below for the relative use of composites on civil aircraft.



As far as I know Airbus is yet to finalise the final design or manufacturing techniques for the 350, that is due to happen next year with the design freeze, in the mean time I know that some 16 different options are being studied.
Human rights lawyers are "ambulance chasers of the very worst kind.'" - Sky News
 
glacote
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 2:19 pm

Quoting Elvis777 (Reply 63):
You hit the nail in the head. I am not claiming either actually . I simply wanted to ensure that whatever Mr. Clark says should be taken with a grain of salt. He is not the burning bush and so whatever comments he makes should as definitive proof or a concept/idea.

On the A388 Tim Clark commented on factual figures gathered on actual route-proving flights by an existing, production A388. Here he throws claims as to what the next aerospace enginerring revolution will look like. What's his background in engineering again?

Not to say that I would believe what he says - the comparison just does not hold water. Just observe that in both instances it is his best customer interest to make claims as he does.
 
rverginia
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 2:45 pm

The "hoops" as you call them, are also composite with the exception of the doorways and barrel join areas, which are titanium.
The argument as to which is more profitable for the airline really comes over the long run. Eliminating lap joins and panel seals also eliminates potential for leaks and corrosion. It means longer time between service and literally and endless lifespan.
To the passenger it means higher pressurization and higher humidity since a barrel can take it better than panels.

As I watch the 1st airplane roll down the line, I am amazed at it's beauty and clean lines. It is saying something about what the airlines want when you see that almost 600 airplanes have been ordered even before that first airplane was built. July 8, 2007 (7/8/7) you will see the future of aviation roll out of the Everett fact
 
firennice
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 3:25 pm

Quoting Zeke (Reply 79):
Airbus has a lot of expertise and knowledge with composites, more than people give them credit for, please see below for the relative use of composites on civil aircraft

They both have a lot of experience with composites. But when you compare the two companies Boeing has a large lead in that race. We see engineers for testing and drilling from both companies. There is a distinct edge. Boeing walks in and knows what to expect. They send many square feet of CFRP for testing. The tests are fast (few days) with many different variations of the tests being performed. They also have projections; how each test with the CFRP should perform, failure rates, hole sizes, tool wear, % of out of tolerance holes. Though they may not allways be right.

Airbus engineers send us materials or pull out this tiny piece of material materials and say...."lets see what happens if..." They 'hope' to get some results, but they dont have any true projections of what they think will happen.

Its a different mindset. One group has been working with the materials for decades and shared that material throughout the company. The other has less experience and shares the knowledge within the company sparingly.
 
justloveplanes
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 3:31 pm

Quoting SEPilot (Reply 19):
I suspect that this was a management decision based on time and money;



Quoting SEPilot (Reply 19):
From what I have read here I have gotten the impression that the engineers all wanted to go to barrels, but management vetoed it. If this is the case it is understandable due to the financial problems created by the A380 and the widespread impression (voiced by John Leahy) that the 787 caught them napping and therefore they need an answer quickly, even if it is not the best they can do.

 checkmark   checkmark 

It is very obvious that complex structures are inherently more problematic than simpler ones. Reducing numbers of parts for a given function is always a manufacturing objective for efficiency reasons and using integral parts for engineering strength is another one. Airbus can build composite barrels I'm sure, but if they wait too long, they will miss the growth cycle and lose too much ground to Boeing, so they are going with something that can meet a competitive delivery time frame.

I think its the wrong decision BTW. Regarding the A350, I think A still has yet to make a right decision. A panel A350 will be a less advanced airplane structurally, and if Boeing ramps up production, the early panel A350 may not be that much an advantage as Boeing will have an edge over a longer time span. They should go for the barrels, they need this technology anyway for Y1. They should have stuck with the original A350 to stem the floodgates while the barrel A350 was being built.
 
sstsomeday
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 3:32 pm

Quoting T773ER (Thread starter):
Gordon McConnell, chief engineer for the A350, said Airbus was sticking with plans to build the jet out of frames made of similar lightweight composite materials."



Quoting MCIGuy (Reply 1):
Then the A350 is at serious risk, and this is not overstated.



Quoting MCIGuy (Reply 5):
All it takes is the perception that the A350 isn't as high-tech as the 787.



Quoting EI321 (Reply 21):
Unless the 787 has lower operating costs then the Barrel argument is a superficial one.

Many opinions here, yet I believe this difference in construction and materials is potentially a bigger liability for Airbus than just perception.

I understand there is a cost savings expected in fuel from the 787s lighter weight, full barrel construction, therefore advantages with payload or range as well. Carrying less fuel means carrying more payload or flying further.

Also lower maintenance costs are expected for the higher composite (barrel) design.

In taking a less aggressive / more economical approach to building the 350 (panel composite construction rather than barrel), Airbus may be saving money in the developmental stage, during their present financial difficulties, but subsequently building a less competitive bird.

Perhaps Airbus are factoring in the likelyhood of losing further business to Boeing if there is another delay with the 350, and so the choice of panel construction will prevent further delay to EIS.
I come in peace
 
astuteman
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 3:39 pm

Quoting CygnusChicago (Reply 70):
At the end of the day what matters is what he does with his money.

Tip for all......
Watch the body language, not the words.....  thumbsup 
 Smile

Regards
 
azhobo
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 4:37 pm

Quoting SEPilot (Reply 19):
(voiced by John Leahy) that the 787 caught them napping and therefore they need an answer quickly

Quite an understatement by Leahy. Van Winkle was caught napping, airbus management had no clue.

HOBO
 
mrcomet
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 5:19 pm

Quoting Dougloid (Reply 72):
It's also possible that they looked at the idea of monolithic CFRP construction and said "two more years until EIS-we just can't afford to sit on our asses and make no money until 2015 instead of 2013. We've got to sell some damn planes."



Quoting Dougloid (Reply 72):
All I've got to add to it is that there is the issue of timing and expense here.

I think you nailed it here. I think this was never driven by technology as much as fielding a plane in the time needed and at the cost needed. Delaying a plane until 2015 might just take them out of the game. That'll mean Boeing has the time to refine the 787 approach to put out a direct competititor. Airbus could loose it all.

Airbus needs to sell planes TODAY. They can't really do that if they go with the monolithic CFRP construction because there is probablyt too many unknowns.

With this approach, they can sell planes today and compete against the 777, their real target.

I don't think Airbus has come up with a better approach than the 787 but it might be good enough to whack the 777.

My question is why would airplanes buy the A350 now? Why not wait until the numbers are clearer. Airbus has a serious credibility problem with numbers whereas Boeing has been more conservative and more accurate on their final numbers even besting them on the 777. I would say Airbus is a risky proposal right now being driven by market and sales. If I was an airline, I'd hang around four more years and see what Boeing has up their sleeve. One thing you can always count on Airbus is they'll give you a steep discount and they'll build planes quickly.
The dude abides
 
Joni
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 6:50 pm

Quoting MCIGuy (Reply 5):
All it takes is the perception that the A350 isn't as high-tech as the 787. Wink

"it"? If the A350 has better operating economics it'll win sales, if the B787 has better economics it'll win sales. We'll see how it goes as the planes enter service.

Quoting SEPilot (Reply 42):

I do not believe this to be the case; it is entirely unnecessary. The 787 has composite hoops inside the barrels and stringers built in; these will provide all the structure necessary. The joints between barrel sections are the easiest kind to make rigid and airtight.

"Boeing said 15 percent of the frame of its 787 jetliner is titanium", from
http://www.iht.com/articles/2006/04/12/bloomberg/sxasia.php

Recall that only 50% of the primary structure B787 will be CFRP, by weight, so there's a good deal of metals in there. This isn't a crisis, these metals are very good materials!

Quoting SEPilot (Reply 45):
The issue of the wings seems to be whether the ribs are aluminum or composite on the A350; it seems that they are aluminum on the 787. Anyone know why Boeing did not make them composite? I assume that there is a reason.

Perhaps aluminium was a better material for the Boeing wing? Recall that composites aren't automatically lighter for a given task, although they often are.
 
Lumberton
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 7:11 pm

Quoting CygnusChicago (Reply 70):
At the end of the day what matters is what he does with his money.

Point of order: it's not his money; it's the al Maktoum's money. These gents will make the decision; Mr. Clark will execute. Since these same gents are the ruling family of Dubai Inc., is it unreasonable to believe that there will be some politics entering into the decision making calculus?
"When all is said and done, more will be said than done".
 
Tristarsteve
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 7:19 pm

Quoting Glacote (Reply 80):
On the A388 Tim Clark commented on factual figures gathered on actual route-proving flights by an existing, production A388. Here he throws claims as to what the next aerospace enginerring revolution will look like. What's his background in engineering again?

Don't think he has one.
When I knew him he was Crew Planning Controller for Gulf Air in BAH, before leaving to join Emirates when it started. He came to GF from British Caledonian where he was in operations control.
 
parapente
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 7:42 pm

So the discussion goes on...and on. However the A350 is not targeting (much) the "barrel" 787 but the Aluminum 777-200 er/lr and 777-300 er. It will beat them hands down and the buyers (and Boeing know it). Why do you think you are "suddenly" reading about the very thing that Boeing has been denying for so many years. That the 777 can be stretched to a 400 after all! Yup its the old trick of getting better economics against a better/newer compeditor. Look at the "Dreamlifter" can you put a composite 777 sized barrel in that -no you can't and Airbus know it.

So we now hear that the BWB is going to happen (in F version). But "the problem is pressurisation/shape". Hmmm now what technology would be useful for this.Hmmm Pannels?
 
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SEPilot
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 7:51 pm

Quoting UA76Heavy (Reply 74):
Boeing have an exclusivity clause in their contracts which prevents Airbus from having access to this knowledge (and rightfully so since there is a lot of proprietary knowledge involved).

Absolutely true; this was explicitly stated by Mike Bair, head of the 787 program.

Quoting Zeke (Reply 79):

Airbus has a lot of expertise and knowledge with composites, more than people give them credit for, please see below for the relative use of composites on civil aircraft.

This certainly used to be true; it seems that sometime since the 777 was developed Boeing decided that composites was the way to go and started researching them big-time, and Airbus didn't notice. Boeing now seems to have a substantial advantage, as the following quote points out.

Quoting Firennice (Reply 82):
They both have a lot of experience with composites. But when you compare the two companies Boeing has a large lead in that race. We see engineers for testing and drilling from both companies. There is a distinct edge. Boeing walks in and knows what to expect. They send many square feet of CFRP for testing. The tests are fast (few days) with many different variations of the tests being performed. They also have projections; how each test with the CFRP should perform, failure rates, hole sizes, tool wear, % of out of tolerance holes. Though they may not allways be right.

Airbus engineers send us materials or pull out this tiny piece of material materials and say...."lets see what happens if..." They 'hope' to get some results, but they dont have any true projections of what they think will happen.



Quoting SSTsomeday (Reply 84):
In taking a less aggressive / more economical approach to building the 350 (panel composite construction rather than barrel), Airbus may be saving money in the developmental stage, during their present financial difficulties, but subsequently building a less competitive bird.

 checkmark 
Exactly the point I have been trying to make.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
Wsp
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 9:12 pm

Quoting Pygmalion (Reply 71):
If Airbus actually said this they should be sued for lying.

No please don't. That would clog up the judiciary if we start suing whenever people are lying.

Quoting Pygmalion (Reply 71):
I don't think that they did. This is wishful thinking. All engineers know that in a pressure vessel the longitudinal joints fatigue faster than the circumferential ones. Have you ever seen a formed beer can burst? The sides split, the ends don't come off. This can be also be seen by looking at ANY all-aluminum aircraft and reviewing the maintenance review book required to be published at delivery. It outlines the inspection requirements for all joints at given intervals for keeping the aircraft flight worthy. Lap longitudinal joints are much more highly loaded than the circumferential joints. This reduces the fatigue life and reduces the time interval between inspections. Current major inspection interval (D check) for the 787 is 12 years IIRC. Unless Airbus greatly increases the material thicknesses to reduce the stress levels in the lap joints, there is no way they will be able to get a 12 year period between inspections on the laps. Just the bolt bending stresses in the fasteners will drive reduced intervals. These inspections require the removal of the interior to expose both the inside and outside of the joint. Not cheap.

Joint doesn't equal joint... Hoop loads on longitudinal joints is much higher.

Maintenance costs (read as inspection costs) will be much higher for an airplane with longitudinal joints. Going full barrel sections is one of the major reasons that the 787 has such reduced maintenance.

http://www.eads.net/eads/special/investor/a350/index.html
roughly at 24:45

"The reality is that the lateral joints are relatively lighty loaded when compared with the circumferential joints ..."
"This allows us to have some relatively lightly loaded lateral joints offsetting the effect of the circumferential joints..."
 
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SEPilot
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 9:33 pm

Quoting Wsp (Reply 93):

"The reality is that the lateral joints are relatively lighty loaded when compared with the circumferential joints ..."

This is not possible unless Airbus has succeeded in rewriting the laws of physics, or the joints are massively overbuilt, or that they are transferring the stresses to the aluminum frames, at which point they are subject to fatigue. The forces of pressurization are going to have to be contained, and the joints between the panels have to resist the pressure. This is one of the greatest continuous stresses on the airframe.
The problem with making things foolproof is that fools are so doggone ingenious...Dan Keebler
 
Dougloid
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 10:25 pm

Quoting SEPilot (Reply 92):
This certainly used to be true; it seems that sometime since the 777 was developed Boeing decided that composites was the way to go and started researching them big-time, and Airbus didn't notice. Boeing now seems to have a substantial advantage, as the following quote points out.

Don't underestimate the value that the research on composite military aircraft and on the Beech Starship added to this project.

I b'lieve I opined here that this meant that a substantial body of expertise in the process of constructing entire aircraft out of CFRP had been developed in the US. In particular, the follow on information as far as airframe durability/serviceability was most significant.
If you believe in coincidence, you haven't looked close enough-Joe Leaphorn
 
cygnuschicago
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 10:26 pm

Quoting Elvis777 (Reply 73):
But I hate that game b/c life is much more complicated than that. You come up with an example I come up with a counter example. Kind of high school ish...

I think we're saying the same thing in different ways. Most of the time, we get a very edited version. Remember, we rarely hear what Clark (or Leahy, or Carson, or whomever) say in full. We just get a soundbite from some reporter, which is probably more often than not taken out of context.

At the end, what counts, is the mighty dollar. Until Clark votes for the 787 over the A350, I view his reported comments as interesting, nothing more. And you're right, something that's one person's "perfect" plane, may not be someone elses. So, for EK, the E380 may be stellar, for, say, SAA, it may be a total disaster.
If you cannot do the math, your opinion means squat!
 
jacobin777
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RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 10:39 pm

Quoting Parapente (Reply 91):

So we now hear that the BWB is going to happen (in F version). But "the problem is pressurisation/shape". Hmmm now what technology would be useful for this.Hmmm Pannels?

..er, since a BWB is a completely different plane from a tube-shaped plane its quite obvious it might need a different manufacturing process...fairly obvious innit?

Quoting Parapente (Reply 91):
hy do you think you are "suddenly" reading about the very thing that Boeing has been denying for so many years. That the 777 can be stretched to a 400 after all!

....er..no, Boeing really doesn't have any plans for that... no 

Quoting Parapente (Reply 91):
Look at the "Dreamlifter" can you put a composite 777 sized barrel in that -no you can't and Airbus know it.

....and?
"Up the Irons!"
 
iwok
Posts: 979
Joined: Wed Jan 26, 2005 2:35 pm

RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 10:52 pm

Quoting Dank (Reply 78):
"The fuselage is a conventional monocoque, but to maximize cargo volume, the cross section is not a true circle. Primary support structures, such as the skin, stringers, and frames, are aluminum.

Thanks for the post. That debunks one a.net myth. I always thought that Airbus was doing a composite fuse on the A400.

It seems like there is quite a bit of catchup to do.

iwok
 
bigjku
Posts: 1906
Joined: Sat Feb 17, 2007 10:51 pm

RE: Airbus Sticks With Panels For The A350

Tue Jun 05, 2007 10:52 pm

Quoting Rheinbote (Reply 36):
AFAIK the 787 wing has monolithic CFRP skins with integral co-bonded stringers, CFRP C-section front and rear spars, and machined aluminum ribs. Ditto for the A350XWB, so no use in starting an A vs B mudfight over wing materials

Thank you for finally answering this.

Quoting Parapente (Reply 91):
So the discussion goes on...and on. However the A350 is not targeting (much) the "barrel" 787 but the Aluminum 777-200 er/lr and 777-300 er.

The 787 and A350XWB will compete in the same market. They are both 9 wide airliners. There is a 5 inch width difference. The only real difference is that Airbus is starting off with a plane that is 198 feet long vs the 787 starting at 186 feet. Presumably at a given length they will hold pretty much the same number of passengers as the A350 will not seat 10 wide in any real configuration.

There is really no reason Boeing could not modify the wing of the 787 for HGW variants and compete with the A350 across the length of whatever market Airbus wants to put it into. This myth really needs to die.

Quoting Parapente (Reply 91):
So we now hear that the BWB is going to happen (in F version). But "the problem is pressurisation/shape". Hmmm now what technology would be useful for this.Hmmm Pannels?

BWB have a lot of routes they can go other than that. The area that is has pressure does not really have to be the whole BWB, you can just put tubes internal of the BWB.

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