User avatar
scbriml
Posts: 13365
Joined: Wed Jul 02, 2003 10:37 pm

Airbus To Strengthen A380 Wing

Mon May 22, 2006 4:46 pm

In today's electronic version of FI, Airbus has briefed A380 customers on wing modifications it will make as a result of the static test failure just short of the required 150%.

Airbus will retro-fit reinforcements to certain stringers in the aircraft already built and produce modified components for newly produced wings.

The modifications will add just 30kg (16kg for the reinforcement strips and 14kg for bolts) to the weight of the A380.
Time flies like an arrow. Fruit flies like a banana!
 
Molykote
Posts: 1237
Joined: Tue Aug 23, 2005 8:21 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 4:52 pm

Quoting Scbriml (Thread starter):
The modifications will add just 30kg (16kg for the reinforcement strips and 14kg for bolts) to the weight of the A380.

Good news.

That's a pretty minimal weight penalty considering that even the 0.0X of a "g" failure margin represents a substantial amount of load/bending moment.
Speedtape - The aspirin of aviation!
 
leelaw
Posts: 4520
Joined: Sat May 29, 2004 4:13 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 4:53 pm

Flight International, 23 May 2006 by Andrew Doyle/Berlin

Manufacturer to add strips to stringers after test rupture

...The manufacturer plans to retrofit reinforcements to certain stringers in Aircraft that have already been built and produce modified components for subsequent wings, said Airbus Chief Operating Officer and A380 programme head Charles Champion at last week's ILA show in Berlin.

"Our conclusion is that we going to add a few strip to stringers in the wing area involved," he said. The strips will be fitted on top of the stringers to "increase the resistance of the stringers at the limit [load]." The proposed changes have been submitted to the EASA for approval.


The article indicates customers have been briefed but doesn't report how much work will be involved.

[Edited 2006-05-22 09:56:29]
Lex Ancilla Justitiae
 
astuteman
Posts: 6341
Joined: Mon Jan 24, 2005 7:50 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 5:16 pm

Quoting Scbriml (Thread starter):
The modifications will add just 30kg (16kg for the reinforcement strips and 14kg for bolts) to the weight of the A380.

One presumes this means only a 16kg increase on new wings on the assumption that the additional fasteners will not be required. Sounds like a fairly minor impact after all of our debating  Smile

Nice to see a resolution being published at long last too.

I'm assuming that they won't re-test, but use analysis of the additional strengthening to gain approval.

Regards
 
andessmf
Posts: 5689
Joined: Wed Jan 25, 2006 8:53 am

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 5:21 pm

Oh, man, I started to read this with a little trepidation, but it looks like Airbus can fix this problem easily. But from the story itself, this fix will still need to be approved by the authorities.
 
PhilSquares
Posts: 3371
Joined: Sun Mar 28, 2004 6:06 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 5:31 pm

Funny thing is Airbus' position had been they didn't need to do anything. They maintained the production wings had been improved. Apparently they were somewhat mistaken!
Fly fast, live slow
 
User avatar
sebolino
Posts: 3495
Joined: Tue May 29, 2001 11:26 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 5:39 pm

Quoting PhilSquares (Reply 5):
Funny thing is Airbus' position had been they didn't need to do anything

I doubt they ever said "we won't do anything about it".

The test seems to have been efficient: a weakness have been found and the corresponding modification also. Very good !
 
atmx2000
Posts: 4301
Joined: Wed Oct 13, 2004 4:24 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 5:41 pm

Quoting Astuteman (Reply 3):
I'm assuming that they won't re-test, but use analysis of the additional strengthening to gain approval.

Good news on weight, but whether a retest was required was always the big question in my mind. I'm not upto snuff about what they have said about the wing. I recall there being questions regarding whether there was wing damage from previous testing and whether the tested wing was a heavier wing and not a lighter wing created after the weight reduction program.
ConcordeBoy is a twin supremacist!! He supports quadicide!!
 
PhilSquares
Posts: 3371
Joined: Sun Mar 28, 2004 6:06 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 5:57 pm

Quoting Sebolino (Reply 7):
I doubt they ever said "we won't do anything about it".

Please re-read what I wrote. I didn't quite say "won't"; what I did say was "didn't need".

If you doubt the accuracy of my statement please see this:

http://www.flightglobal.com/Articles...wing+is+compliant+after+early.html
Here's the quote by Alain Garcia, VP Engineering at Airbus. "Garcia says: “We will use this calibration of the FEM to prove the adequacy of the structure on production aircraft,” adding that “essentially no modifications” will be required for production aircraft: “We have refined the structural design for subsequent aircraft due to increased weights, etc.”
Fly fast, live slow
 
User avatar
sebolino
Posts: 3495
Joined: Tue May 29, 2001 11:26 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 6:18 pm

Quoting PhilSquares (Reply 9):
Please re-read what I wrote. I didn't quite say "won't"; what I did say was "didn't need".

Yes, but you still said "do anything" ... like if they were looking at the problem like disoriented guilty children.

Just looking at the original thread:

Based on Noel Forgeard comment's in the March 14 FI, it sounds like structural strengthening will be required, but no re-test.

Exactly what was said, for the moment.
 
PhilSquares
Posts: 3371
Joined: Sun Mar 28, 2004 6:06 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 6:32 pm

I guess, from my perspective, the VP engineering says " essentially no modifications" that means they don't have to do anything.

I provided you the quoted text, the link. You can read it anyway you want, but I stand by my remarks.

Forgeard's business is to sell airplanes, Garcia's is to engineer them. Big difference.

Bottom line, I think, is Airbus has royally botched the 380. If the wing has to be retested, which I am sure will happen if you read the FI link I provided, the deliveries will be delayed until next year. If that happens, you will see the 380 program flounder worse than it currently is.
Fly fast, live slow
 
Joni
Posts: 2613
Joined: Thu Aug 10, 2000 11:05 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 7:06 pm

Quoting PhilSquares (Reply 11):
I guess, from my perspective, the VP engineering says " essentially no modifications" that means they don't have to do anything.

I think 30kg of added weight easily falls into the category "essentially no modifications".
 
WINGS
Posts: 2312
Joined: Tue May 31, 2005 1:36 am

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 7:25 pm

Quoting PhilSquares (Reply 11):
Forgeard's business is to sell airplanes, Garcia's is to engineer them. Big difference.

Well this is an interesting way to look at things. Mr Forgeard looks like an idiot but I'm sure that he is far from being one.

Quoting PhilSquares (Reply 11):
Bottom line, I think, is Airbus has royally botched the 380. If the wing has to be retested, which I am sure will happen if you read the FI link I provided, the deliveries will be delayed until next year. If that happens, you will see the 380 program flounder worse than it currently is.

PhilSquares, why is it that I always get the impression that you would like the A380 program to fail?

Maybe you should approach Mr Chew, and bring up your concerns in regards to the A380. After all they will be taking up a few botched up A380 in the near future.  Yeah sure

Regards,
Wings
Aviation Is A Passion.
 
Joni
Posts: 2613
Joined: Thu Aug 10, 2000 11:05 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 7:31 pm

Quoting PhilSquares (Reply 11):
If the wing has to be retested, which I am sure will happen if you read the FI link I provided,

From the FI story you linked to we have:


Jonathan Howes, technical director of UK-based certification consultants AeroDAC and, until recently, leading structures certification specialist for the A380 at the UK Civil Aviation Authority, says the rupture “was so close to the ultimate target that it is almost certain to allow approval to be given without the need for a re-test, but this will be subject to a negotiation between Airbus and EASA”.


How can you reach the opposite conclusion from reading the same text?
 
PhilSquares
Posts: 3371
Joined: Sun Mar 28, 2004 6:06 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 8:54 pm

Quoting WINGS (Reply 12):
Well this is an interesting way to look at things. Mr Forgeard looks like an idiot but I'm sure that he is far from being one.

Interesting way to twist things, but that was not my implication, stated or otherwise. So, don't try to put things into my postings.

Quoting WINGS (Reply 12):
PhilSquares, why is it that I always get the impression that you would like the A380 program to fail?

Maybe you should approach Mr Chew, and bring up your concerns in regards to the A380. After all they will be taking up a few botched up A380 in the near future.

Honestly, I could really care less what happens. I have 5+ years left until I hit 60, I'm very happy to stay on the 747-400. I have flown the 320, with over 2500 PIC have been a TRI/TRE, I know Airbus systems, I have never stated any thoughts either way. So, again, don't try read anything into my posts.

Quoting Joni (Reply 13):
How can you reach the opposite conclusion from reading the same text?

I don't believe he works for the CAA anymore so what he thinks or believes is really irrelavant. More importantly it's what the JAA/FAA think. The FAA has made their position very clear. Does that mean it's cast in stone? No, but it sure does make it very difficult for a joint certification. Or Airbus could always do a certification for the JAA and then another for the FAA.
Fly fast, live slow
 
User avatar
sebolino
Posts: 3495
Joined: Tue May 29, 2001 11:26 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 9:15 pm

Quoting WINGS (Reply 12):
Mr Forgeard looks like an idiot but I'm sure that he is far from being one.

Very true.  Smile

Actually, with his face, he must be really brilliant to have convinced people to let him lead Airbus.
 
leelaw
Posts: 4520
Joined: Sat May 29, 2004 4:13 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 9:39 pm

Quoting Sebolino (Reply 15):
Actually, with his face, he must be really brilliant to have convinced people to let him lead Airbus.

Leprechauns are known to have certain abilities where treasure is concerned. Big grin
Lex Ancilla Justitiae
 
NAV20
Posts: 8453
Joined: Thu Nov 27, 2003 3:25 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 9:40 pm

Quoting Joni (Reply 13):
How can you reach the opposite conclusion from reading the same text?

I don't see how anyone can reach conclusions either way. It's perfectly clear from the report that this is an Airbus proposal. EASA/FAA may accept it, or they may decide that further strengthening is required, or they may insist on a further full-scale test of the modified wing.
"Once you have flown, you will walk the earth with your eyes turned skywards.." - Leonardo da Vinci
 
Joni
Posts: 2613
Joined: Thu Aug 10, 2000 11:05 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 10:05 pm

PhilSquares, you wrote that you are "sure" the wing will have to be re-tested and mentioned the article as a source of this certainty. I was just pointing out, that from reading the article it's difficult to be able to join your certain position:


until recently, leading structures certification specialist for the A380 at the UK Civil Aviation Authority, says the rupture “was so close to the ultimate target that it is almost certain to allow approval to be given without the need for a re-test, but this will be subject to a negotiation between Airbus and EASA”.
 
col
Posts: 1692
Joined: Thu Nov 27, 2003 2:11 am

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 10:12 pm

PhilSquares, how dare you use hard facts, and Airbus own words to discredit the 380, what are you thinking Big grin
 
DAYflyer
Posts: 3546
Joined: Wed Sep 08, 2004 9:35 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 10:13 pm

Quoting PhilSquares (Reply 5):
Funny thing is Airbus' position had been they didn't need to do anything. They maintained the production wings had been improved. Apparently they were somewhat mistaken!

Another PR flub. Just what they needed after all the delays of EIS.

I wonder if it has dawned on anyone that the PR dept may be in need of overhaul.
One Nation Under God
 
WINGS
Posts: 2312
Joined: Tue May 31, 2005 1:36 am

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 10:37 pm

Quoting PhilSquares (Reply 14):
Interesting way to twist things

Well we get used to these kind of things around here.

Quoting PhilSquares (Reply 14):
but that was not my implication, stated or otherwise

Well you could have fooled me.  Wink

Quoting PhilSquares (Reply 14):
So, don't try to put things into my postings.

Never did. I was just simply pointing out how we share very different point of view.

One that caught my eye was the following.

Bottom line, I think, is Airbus has royally botched the 380.

Quoting Sebolino (Reply 15):

Very true. Smile

Actually, with his face, he must be really brilliant to have convinced people to let him lead Airbus.

How very true.

Regards,
Wings
Aviation Is A Passion.
 
Dougloid
Posts: 7248
Joined: Tue Jul 05, 2005 2:44 am

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 10:55 pm

Quoting Leelaw (Reply 2):
Flight International, 23 May 2006 by Andrew Doyle/Berlin

Manufacturer to add strips to stringers after test rupture

...The manufacturer plans to retrofit reinforcements to certain stringers in Aircraft that have already been built and produce modified components for subsequent wings, said Airbus Chief Operating Officer and A380 programme head Charles Champion at last week's ILA show in Berlin.

"Our conclusion is that we going to add a few strip to stringers in the wing area involved," he said. The strips will be fitted on top of the stringers to "increase the resistance of the stringers at the limit [load]." The proposed changes have been submitted to the EASA for approval.

The article indicates customers have been briefed but doesn't report how much work will be involved.

Wouldn't be the first big fella to wear a truss, Rupture-Eez or similar.

I worked on a Britt Airways Metroliner one time, it had had the MLG collapse in Carbondale Illinois. Well, what actually happened was the pilot was a bit of a hot dog, selected the up position on the takeoff roll so as to suck up the gear as soon as it broke ground. Well, it hit a whoops-de-do and that unloaded the squat switch enough that the gear started up, them Mr. Bozo chopped the power. It ground the keelsons pretty good in the engine nacelles and did a lot of other damage. Since the edge of the spar is exposed, it ground that pretty good too.

The Fairchild factory in San Antonio built an external jockstrap that went on top of the spar cap and beefed it up. The original was cleaned off, fastener holes were added, the jockstrap/rupture truss was attached with huckbolts, and it was flying happily for some years after-maybe even to this day.
If you believe in coincidence, you haven't looked close enough-Joe Leaphorn
 
PolymerPlane
Posts: 832
Joined: Thu May 11, 2006 1:12 am

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 11:05 pm

I thought Airbus said first that the production wings are stronger than the test wings, then the wing they used was already broken before they used it for ultimate test load such that the new wing would have been much much stronger than the "broken one. Now they said they need to put 30 kg reinforcement. Now, people said Airbus did not put any spin to this problem, only some Boeing cheerleaders that wants A380 to fail. I think we all need to see the facts of the matter.

On a side note, when Airbus said that the production wings has been modified from the test wings, isn't it dangerous to present a test wings that has been altered from production wings? I thought the certification test is to test whether the production wings are airworthy. If the test wing is different from the production wings, how can you certify the production wing? Something smells fishy here.

Cheers,
PP
One day there will be 100% polymer plane
 
PhilSquares
Posts: 3371
Joined: Sun Mar 28, 2004 6:06 pm

RE: Airbus To Strengthen A380 Wing

Mon May 22, 2006 11:24 pm

Quoting WINGS (Reply 21):
Never did. I was just simply pointing out how we share very different point of view.

One that caught my eye was the following.

Bottom line, I think, is Airbus has royally botched the 380.

1) I don't have a point of view concerning the 380. It hasn't been in revenue service yet, in fact, it hasn't even been certified yet. It's still an experimental aircraft!

2) Just out of courtesy, I'd let someone know when you make a statement bold that wasn't printed that way originally.

3) With reference to your last statement, I just think Airbus needs to get it's PR act together. Airbus has flip flopped on this issue. As has been pointed out in these posts, Airbus initially said the wing tested was not as strong as the production version, so there was no need to do anything (Please note I said need). Since the wing failed at 1.47 load that was close enough to 1.5 where Airbus and JAA could extrapolate the results on the production wing.

Now we have a kit for wings already produced and a design change for all future wings. Those are two diametrically opposed statements.

Quoting WINGS (Reply 21):
Well we get used to these kind of things around here.

So that makes it acceptable?
Fly fast, live slow
 
NAV20
Posts: 8453
Joined: Thu Nov 27, 2003 3:25 pm

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 12:03 am

Quoting PolymerPlane (Reply 24):
If the test wing is different from the production wings, how can you certify the production wing? Something smells fishy here.



Quoting PhilSquares (Reply 25):
As has been pointed out in these posts, Airbus initially said the wing tested was not as strong as the production version, so there was no need to do anything

Completely agree with both of you. For confiirmation:-

"However Garcia says that the failure of the wing below the 1.5 target will require “essentially no modifications” to production aircraft: “This static test airframe has the first set of wings built, and we have refined the structural design for subsequent aircraft due to increased weights etc. We will use this calibration of the FEM to prove the adequacy of the structure on production aircraft.”

"Garcia says that the FEM calculations had already established that the A380’s wing had “no margin at ultimate load. We had a weight saving programme and ‘played the game’ to achieve ultimate load.” However in earlier briefings, Airbus structural engineers had stated that it planned to carry out “a residual strength and margin research test” in 2006 after completing ultimate load trials."


http://www.flightglobal.com/Articles...eaks+just+below+ultimate+load.html

The important phrases in those statements, for me, are, "we have refined the structural design for subsequent aircraft due to increased weights etc." and, "We had a weight saving programme and ‘played the game’ to achieve ultimate load.”

Putting those together, one is left with the impression that, if anything, the weight-saving modifications since the wing that failed the tests was built may well, if anything, have reduced wing strength, not increased it.

Airbus should have sacrificed another wing months ago, to prove its strength once and for all. The fact that they haven't concerns me increasingly, and has me thinking the unthinkable; that they are trying to talk their way out of the problem because they themselves are not sure that the results of a further test would be any better.

Can't help a growing feeling that Airbus management are simply not 'aeroplane people'. It shouldn't be up to EASA or the FAA to solve the wing problem. Airbus, from Forgeard down, should be busting a gut, day and night, not sparing any expense, to make damn sure that that aeroplane will be 100% safe.
"Once you have flown, you will walk the earth with your eyes turned skywards.." - Leonardo da Vinci
 
slz396
Posts: 1883
Joined: Tue Oct 02, 2001 7:01 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 12:44 am

Fact is a 30kg modification is apparently more than enough to be officially proposed by the worlds biggest manufacturer of civil airplanes to solve so called 'HUGE problems' which have been discussed to death on this forum despite any one of us having a clue about the real whereabouts really.

Quoting PolymerPlane (Reply 24):
I thought the certification test is to test whether the production wings are airworthy. If the test wing is different from the production wings, how can you certify the production wing? Something smells fishy here.

So you are saying that each time a wing gets MODIFIED somehow, it should be fully retested then?
I think basically 90% of the planes currently flying do so on a wing design which has not been tested physically, but rather by analysis from a previous design, and in this perspective I fail to see why it would matter if the wing actually tested comes from a production model or from a pre-production model?

The problem with all these technical discussions on the A380 testing is that far too many people are getting involved in things which they have never been in contact with before and simply don't know enough about to give a well founded opinion on, yet seem to be all to eager to give it anyhow.
 
User avatar
scbriml
Posts: 13365
Joined: Wed Jul 02, 2003 10:37 pm

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 1:09 am

Quoting NAV20 (Reply 26):
Airbus should have sacrificed another wing months ago, to prove its strength once and for all. The fact that they haven't concerns me increasingly, and has me thinking the unthinkable;

Given the fact that the test wing failed at 96.7% of the target, it was always likely that a further test would not be necessary - as long as the fix that Airbus is now proposing is accepted by the certification authorities.

Airbus can demonstrate that the strengthened stringers are now x% stronger than the ones that failed in the static test, and thus, by analysis, show that a modified wing would pass the test. This is almost certain to be acceptable to the JAA/FAA.
Time flies like an arrow. Fruit flies like a banana!
 
raventom
Posts: 256
Joined: Sat Apr 08, 2006 8:50 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 1:11 am

Is this more delays for SQ?
I love the smell of burnt kerosene!!!!!!!!!!!!
 
leelaw
Posts: 4520
Joined: Sat May 29, 2004 4:13 pm

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 1:16 am

What's conspicuous by its absence from Mr. Champion's comments to FI is the "de rigueur" (of late) "...we do not anticipate this modification will affect the scheduled delivery (and/or EIS) to Singapore Airlines by the end of 2006?" It'll be interesting to see how the forthcoming press release will be worded.
Lex Ancilla Justitiae
 
WINGS
Posts: 2312
Joined: Tue May 31, 2005 1:36 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 1:35 am

Quoting PhilSquares (Reply 25):

1) I don't have a point of view concerning the 380. It hasn't been in revenue service yet, in fact, it hasn't even been certified yet. It's still an experimental aircraft!

That's rather funny PhilSquare, You had no trouble in expressing it with the following reply.

Quoting PhilSquares (Reply 10):
Bottom line, I think, is Airbus has royally botched the 380. If the wing has to be retested, which I am sure will happen if you read the FI link I provided, the deliveries will be delayed until next year. If that happens, you will see the 380 program flounder worse than it currently is.



Quoting PhilSquares (Reply 25):
2) Just out of courtesy, I'd let someone know when you make a statement bold that wasn't printed that way originally.

That's correct PhilSquare. For that reason I apologize. I just wanted to highlight the point in which I was referring to.

Quoting PhilSquares (Reply 25):

3) With reference to your last statement, I just think Airbus needs to get it's PR act together

Absolutely. Airbus has suffered more blows in recent times mainly due to their PR department. It would be in their interest to keep their months shut.

We also have to conclude that many PR issues occur because the translation of various native languages into English.

Quoting PhilSquares (Reply 25):
Airbus has flip flopped on this issue. As has been pointed out in these posts, Airbus initially said the wing tested was not as strong as the production version, so there was no need to do anything (Please note I said need). Since the wing failed at 1.47 load that was close enough to 1.5 where Airbus and JAA could extrapolate the results on the production wing.

However Garcia says that the failure of the wing below the 1.5 target will require "essentially no modifications" to production aircraft:

http://www.flightglobal.com/Articles...eaks+just+below+ultimate+load.html

The modification being mentioned are rather minor. I would not get too carried away.

Quoting PhilSquares (Reply 25):
Now we have a kit for wings already produced and a design change for all future wings. Those are two diametrically opposed statements.

They further improved the design. For that reason I congratulate them. At the end of the day what really matters is safety.

Regards,
Wings
Aviation Is A Passion.
 
greasespot
Posts: 2955
Joined: Sat Apr 24, 2004 10:48 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 1:40 am

Quoting NAV20 (Reply 26):
Airbus should have sacrificed another wing months ago, to prove its strength once and for all. The fact that they haven't concerns me increasingly, and has me thinking the unthinkable; that they are trying to talk their way out of the problem because they themselves are not sure that the results of a further test would be any better.

And the fact the Boeing did exactally the same thing with the B737 classics when it's wing failed somehow does not concern you?

http://www.b737.org.uk/history.htm

There was also a flight internationl article that said boeing did not re-do the test. They just used models, like Airbus is doing, to show their strengthing is enough. It was their article that was out a couple months ago celebrating the B737 anniversary.




GS
Sometimes all you can do is look them in the eye and ask " how much did your mom drink when she was pregnant with you?"
 
halls120
Posts: 8724
Joined: Sun Jun 05, 2005 3:24 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 2:12 am

Quoting WINGS (Reply 31):
We also have to conclude that many PR issues occur because the translation of various native languages into English

A pretty lame conclusion, if you ask me. At least part of the Airbus PR department must be native English speakers - what's their excuse?

Quoting WINGS (Reply 31):
They further improved the design. For that reason I congratulate them. At the end of the day what really matters is safety.

Agree.
"Suppose you were an idiot. And suppose you were a member of Congress. But I repeat myself." Mark Twain, a Biography
 
Dougloid
Posts: 7248
Joined: Tue Jul 05, 2005 2:44 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 2:32 am

Quoting Slz396 (Reply 27):
So you are saying that each time a wing gets MODIFIED somehow, it should be fully retested then?
I think basically 90% of the planes currently flying do so on a wing design which has not been tested physically, but rather by analysis from a previous design, and in this perspective I fail to see why it would matter if the wing actually tested comes from a production model or from a pre-production model?

What's your source of authority for making that statement?

Quoting Slz396 (Reply 27):
The problem with all these technical discussions on the A380 testing is that far too many people are getting involved in things which they have never been in contact with before and simply don't know enough about to give a well founded opinion on, yet seem to be all to eager to give it anyhow.

Oh that's right. See the above.

Quoting Scbriml (Reply 28):
Airbus can demonstrate that the strengthened stringers are now x% stronger than the ones that failed in the static test, and thus, by analysis, show that a modified wing would pass the test. This is almost certain to be acceptable to the JAA/FAA.

Do not assume that what you think to be just and reasonable is the same as what a governmental unit will demand. There's no connection there.
If you believe in coincidence, you haven't looked close enough-Joe Leaphorn
 
PolymerPlane
Posts: 832
Joined: Thu May 11, 2006 1:12 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 2:54 am

Quoting Slz396 (Reply 27):
So you are saying that each time a wing gets MODIFIED somehow, it should be fully retested then?
I think basically 90% of the planes currently flying do so on a wing design which has not been tested physically, but rather by analysis from a previous design, and in this perspective I fail to see why it would matter if the wing actually tested comes from a production model or from a pre-production model?

Well I do not know the 90% statistics, but the fact of the matter is that even when the original design is not certified, yet Airbus has made modification, which involves reductions. I do not know how accurate is the computer modelling in predicting the change in the wing strength with respect to the weight reduction. If it is the case, a sneaky airplane manufacturer could easily make a slightly stronger wing for testing while making a lighter wing for production to satisfy weight guarantees (note: I do not make any suggestion that Airbus is doing it, but a hypothetical company could).

I am sure that the other 90% wings that has not been tested yet, have some kind of base models certified before they are modified. Also, if the modification only takes place in minor parts such as leading edge, flaps or skins, which has almost no impact on the strength of the wing. I am not an expert on aircraft certification process, but as a commoner I think that testing is done because it is important and crucial for the safety of aircrafts, and even computer simulation is so acurate, it is only a prediction of a very complex process.

Cheers,
PP
One day there will be 100% polymer plane
 
WINGS
Posts: 2312
Joined: Tue May 31, 2005 1:36 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 2:58 am

Quoting Halls120 (Reply 33):
A pretty lame conclusion, if you ask me. At least part of the Airbus PR department must be native English speakers - what's their excuse?

Well Airbus is made up of different nationalities, I would not believe that the British arm of Airbus is solely responsible for the Airbus PR. The major problems would lay with the French, German and Spanish arm of Airbus.

I have personal experiences of translations being misinterpreted. I'm both Portuguese and Australian. I have encountered numerous errors in both translations from Portuguese to English and vice versa.

Regards,
Wings
Aviation Is A Passion.
 
OldAeroGuy
Posts: 3188
Joined: Sun Dec 05, 2004 6:50 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 3:45 am

Quoting Scbriml (Reply 28):
Airbus can demonstrate that the strengthened stringers are now x% stronger than the ones that failed in the static test, and thus, by analysis, show that a modified wing would pass the test. This is almost certain to be acceptable to the JAA/FAA.

Agree with this statement although you should say EASA rather than JAA.

Quoting WINGS (Reply 31):
They further improved the design. For that reason I congratulate them.

Disagree with this statement. This wasn't a design improvement. It was a requirement to meet the certification minimum standard.


The main question is: Has this change has already been applied to the SQ A380 that is currently flying? If the modification is yet to be incorporated, can it be done before the Nov. delivery date?
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
astuteman
Posts: 6341
Joined: Mon Jan 24, 2005 7:50 pm

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 3:53 am

Quoting OldAeroGuy (Reply 37):
The main question is: Has this change has already been applied to the SQ A380 that is currently flying? If the modification is yet to be incorporated, can it be done before the Nov. delivery date?

I would imagine the time needed to execute the change as it is described is "trivial" compared to the remaining timescale.
I would guess the key is how quickly Airbus can get the change certified. That might not be trivial (although you'd like to think it would be fairly straightforward ...... Smile)

Regards
 
OldAeroGuy
Posts: 3188
Joined: Sun Dec 05, 2004 6:50 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 4:06 am

Quoting OldAeroGuy (Reply 37):
I would guess the key is how quickly Airbus can get the change certified. That might not be trivial (although you'd like to think it would be fairly straightforward ....

Agree that the cert portion is never trivial. The stringer add-on probably requires entering a wing fuel tank and this is never fun if the airplane has been fueled previously.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
slz396
Posts: 1883
Joined: Tue Oct 02, 2001 7:01 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 4:07 am

Quoting slz396 (Reply 27):
I think basically 90% of the planes currently flying do so on a wing design which has not been tested physically, but rather by analysis from a previous design



Quoting Dougloid (Reply 34):
What's your source of authority for making that statement?

As you could have seen from actually reading carefully what I've said before jumping on your keyboard in anger because somebody might have mentioned a valid point in defence of an analytic A380 wing tests: it is a thought.

Anyway, what do you think will be the percentage of planes flying on wing certified by analysis only? more in the range of 70%? 60% maybe? Or do you think more like 5% or maybe just 2%?

what's the percentage of planes flying around on wings which are not identical to the wings which have been strength tested at initial certification?I'd be interested to hear for instance how many wings Boeing did brake for their entire 737 range over the past decades, from the very first version of the -100 to the -900 for instance? The NG got a new wing, so surely that must have been tested physically too then, right? Oh, but do not some versions of the NG have a modified wing? That means 2 wings must have been broken then?
same for the 747 for instance...
and the 777...
the very same can be said of many Airbus planes too, so don't think for a minute I am partisan just because I use Boeing planes as an example here...

[Edited 2006-05-22 21:11:32]
 
User avatar
scbriml
Posts: 13365
Joined: Wed Jul 02, 2003 10:37 pm

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 4:22 am

Quoting OldAeroGuy (Reply 37):
Agree with this statement although you should say EASA rather than JAA.

Oops! Had my pre Sept 2003 head on. banghead 

Quoting Dougloid (Reply 34):
Do not assume that what you think to be just and reasonable is the same as what a governmental unit will demand.

"Just", "reasonable" and "government" in the same sentence - I'm not that naive. wink  However, there are numerous precedents (including, I believe, the Boeing 737 wing.)
Time flies like an arrow. Fruit flies like a banana!
 
OldAeroGuy
Posts: 3188
Joined: Sun Dec 05, 2004 6:50 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 4:49 am

Quoting Scbriml (Reply 41):
"Just", "reasonable" and "government" in the same sentence - I'm not that naive. However, there are numerous precedents (including, I believe, the Boeing 737 wing.)

Yeah, but a lot has changed in 30+ years. The Cert Agencies aren't as friendly these days.
Airplane design is easy, the difficulty is getting them to fly - Barnes Wallis
 
PolymerPlane
Posts: 832
Joined: Thu May 11, 2006 1:12 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 4:58 am

Quoting Slz396 (Reply 40):

Back to my previous point. You have not even had a wing certified for A380, yet you already introduce modification. What's the point of certification then? just build a tank like wing, test it, and modify it later. It is much easier this way anyway, since you are guaranteed passing the initial test.

I do not know whether 737NG had its wing tested, but we do not know what kind of modification has been made to the wings. I am sure it was not for weight reduction like A380. We do not know whether the modification compromises the wing strength, while A380 had weight reduction program which suggest using less material with a possibility of strength reduction.

Cheers,

PP
One day there will be 100% polymer plane
 
A342
Posts: 4017
Joined: Sun Jul 31, 2005 11:05 pm

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 5:07 am

Quoting OldAeroGuy (Reply 39):
The stringer add-on probably requires entering a wing fuel tank and this is never fun if the airplane has been fueled previously.

It may not be fun, but it can be done without too big difficulties.
Exceptions confirm the rule.
 
User avatar
glideslope
Posts: 1423
Joined: Sun May 30, 2004 8:06 pm

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 5:25 am

Quoting Sebolino (Reply 6):
The test seems to have been efficient: a weakness have been found and the corresponding modification also. Very good !

Well, considering todays engineering recources it certainly make me wonder about the rest of the design.

I could see this if we were in 1966. IMO, the entire notion of having to go back and refit wings already in flight seems draconian at best for a 2006 production airframe.

I still think this is all a result of the Weight Reduction Program. IMO, Airbus will learn a valuable lesson from this.
To know your Enemy, you must become your Enemy.” Sun Tzu
 
ebbuk
Posts: 844
Joined: Thu May 11, 2006 6:47 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 5:33 am

Quoting NAV20 (Reply 26):

Airbus should have sacrificed another wing months ago, to prove its strength once and for all. The fact that they haven't concerns me increasingly, and has me thinking the unthinkable

Me too, Do as Boeing did with 737. Gosh how dare they?
 
474218
Posts: 4510
Joined: Mon Oct 10, 2005 12:27 pm

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 6:15 am

Quoting Scbriml (Reply 28):
Given the fact that the test wing failed at 96.7% of the target, it was always likely that a further test would not be necessary - as long as the fix that Airbus is now proposing is accepted by the certification authorities.

Airbus can demonstrate that the strengthened stringers are now x% stronger than the ones that failed in the static test, and thus, by analysis, show that a modified wing would pass the test. This is almost certain to be acceptable to the JAA/FAA

The problem with your interpretation of the static fatigue test failure is that other than the requirement to meet 150% of the design load all the other numbers came from Airbus. It was Airbus's analysis that predicted where the wing would brake, it was wrong. Now they are saying our analysis says all we have to do is add a some of straps to some stringers and it will now have the strength it should have had in the first place. If their analysis was not right in the first place why is it right now?
 
User avatar
scbriml
Posts: 13365
Joined: Wed Jul 02, 2003 10:37 pm

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 6:46 am

Quoting 474218 (Reply 47):
all the other numbers came from Airbus

 confused  They wouldn't have come from anywhere else would they?

The wing broke a little way short of the required 150%. Airbus, and nobody else, should know exactly what they need to add to make the wing reach 150%. In the case of existing wings, 30kg of reinforcement and bolts (presumably less for new-build wings since the additional bolts won't be required).

Let's see what EASA and FAA say about it after they've seen Airbus's figures.
Time flies like an arrow. Fruit flies like a banana!
 
andessmf
Posts: 5689
Joined: Wed Jan 25, 2006 8:53 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 7:31 am

Quoting Greasespot (Reply 32):
And the fact the Boeing did exactally the same thing with the B737 classics when it's wing failed somehow does not concern you?

The actual quote from the article is:

"Apparently this benefit was over-estimated and a set of wings failed in static tests at 95% of max load so the wing had to be redesigned."

I have not found any reference to what this redesign entailed. But no one is saying at this stage that the A380 wing has been redesigned.
 
Dougloid
Posts: 7248
Joined: Tue Jul 05, 2005 2:44 am

RE: Airbus To Strengthen A380 Wing

Tue May 23, 2006 8:32 am

Quoting A342 (Reply 44):
It may not be fun, but it can be done without too big difficulties.

Spoken with all the air of authority of a man who has spent no time anywhere near a wet fuel tank with the possibility of bashing rivets on his mind.

Son, I do NOT want to pull rank on you here, and I'm generally averse to jumping all over people, no matter how uninformed they seem to be.

But in this case I will make an exception.

If you have ever spent ANY time in a wet tank wearing a respirator trying to drill holes to install fasteners for structure (as I have) after crawling thru a small tank door and getting as far away from the companionship of the world as you can, you would know better than to say what you just did.

There is absolutely no force on earth or underneath it that could get me to go into a wet tank again. Thankfully, my days of earning my bread in that way are I hope long over. The folks at Eden who had to henceforth earn their bread by the sweat of their brow as it says in the Book didn't know the half of it.

Let me tell you something. If you ever get into the aviation trades and you see the crew chief headed your way with a blueprint in one hand and a respirator in the other, if you can pull a disappearing act it's best to do so.

Otherwise, you might better give your heart to Jesus because your ass is owned by the Dark One and his minions.

[Edited 2006-05-23 01:53:12]
If you believe in coincidence, you haven't looked close enough-Joe Leaphorn

Who is online