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Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 19, 2012 12:38 pm

Airbus has traced the source of the cracking in A380 wing structures to unexpected additional stresses imparted by the manufacturing process, and is confident that its original flight loading calculations for the type are accurate.


http://www.flightglobal.com/news/art...s-to-manufacturing-process-367116/
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Stitch
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 19, 2012 12:49 pm

So as many of us suspected, nothing to get worried over and fixes will be made for new-builds (manufacturing) and already-built planes.   
 
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kc135topboom
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 19, 2012 12:52 pm

It does not seem to be a big problem, and should be easily corrected with an updated manufacturing process. However the FG story does not say anything about how turbulance could aggravate the stress cracks on the foot brackets. To me that means the EASA may require an immediate for any of the affected airframes that encounter moderate or worse inflight turbulance.
 
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EPA001
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 19, 2012 1:22 pm

Quoting Stitch (Reply 1):
So as many of us suspected, nothing to get worried over and fixes will be made for new-builds (manufacturing) and already-built planes.

Good to read that they have traced the origin of the problem. The solution to that seems to be quite easy.  
 
tdscanuck
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 19, 2012 3:05 pm

Quoting KC135TopBoom (Reply 2):
However the FG story does not say anything about how turbulance could aggravate the stress cracks on the foot brackets.

It kind of does, since they use a lot of language to say it's a fatigue problem and not a static strength problem. One big overload (like heavy turbulence) has an extremely small impact on the number of cycles and can actually slow down crack growth...this process is called auto-frettage when you do it on purpose. The regulators might drop a short-flow inspection (almost certainly not an immediate) so operators can baseline their crack lengths to establish future inspection intervals but I don't see this altering the post-turbulence/post-overload inspections.

Quoting EPA001 (Reply 3):

Good to read that they have traced the origin of the problem. The solution to that seems to be quite easy.

The solution for future builds is easy...no new design work, just fix the manufacturing process. The fix for as-builts, although mechanically simple, still involves draining the tank, pulling the rib feet, probably oversizing the holes, installing new feet, re-sealing, leak-check, and restore to service...not exactly a fun or quick job.

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EPA001
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 19, 2012 3:39 pm

Quoting tdscanuck (Reply 4):
The fix for as-builts, although mechanically simple, still involves draining the tank, pulling the rib feet, probably oversizing the holes, installing new feet, re-sealing, leak-check, and restore to service...not exactly a fun or quick job.

OK, that is a lot more work. But probably can be done during one of the regular checks for the airframe?
 
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Stitch
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 19, 2012 3:44 pm

Quoting EPA001 (Reply 5):
But probably can be done during one of the regular checks for the airframe?

I believe someone posted in the original thread that the earliest A380 airframes are starting to approach their first C-check, but I don't know if this type of modification would take longer than the normal timeframe for the check.

If the cracks remain manageable (as in pose no worries) and the application of the modification could be pushed out to the first D-check, then I expect that is plenty of time to make the modification during that period.
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 19, 2012 4:37 pm

http://www.reuters.com/article/2012/.../us-airbus-a-idUSTRE80I11G20120119

Airbus (EAD.PA) said on Thursday it had discovered more cracks in the wings of two A380 superjumbo aircraft but insisted the world's largest jetliner remained safe to fly.

The announcement comes two weeks after tiny cracks were first reported in the wings of the 525-seat, double-decker aircraft, which entered service just over four years ago.

"Airbus confirms that some additional cracks have been found on a limited number of non-critical brackets ... inside the wings of some A380s," the planemaker said in a statement.

"Airbus emphasizes that these cracks do not affect the safe operation of the aircraft."

The European Aviation Safety Authority (EASA) confirmed it would issue a bulletin Friday mandating precautionary checks.

...
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 19, 2012 6:39 pm

Quoting LTC8K6 (Reply 7):
The European Aviation Safety Authority (EASA) confirmed it would issue a bulletin Friday mandating precautionary checks.

And here it is on the FG site.

"EASA decided to call for an immediate inspection regime rather than waiting for a regular inspection opportunity. Around a dozen aircraft are likely to be affected."

http://www.aviationweek.com/aw/gener...20Crack%20Inspections&channel=comm
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Fri Jan 20, 2012 12:39 pm

Interesting Aviation Week article - this is a clearly second mode of cracking.

But as the article says, there are 2000 of these brackets per wing, one cracked is probably not too much of an issue.
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Fri Jan 20, 2012 1:42 pm

 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Fri Jan 20, 2012 7:49 pm

Quoting tdscanuck (Reply 4):
It kind of does, since they use a lot of language to say it's a fatigue problem and not a static strength problem.

I took exactly the opposite meaning from the article. It says:

Airbus carries out A380 wing manufacture at the UK plant in Broughton, before transferring the wings to the Toulouse final assembly line. An Airbus wing specialist on the A380 said the airframer's investigations indicated that parts were being stressed at some point during the manufacturing process, which involves drawing the wing skin over the built-up rib and spar assembly before attaching it.

"It's possible to get standing stresses that hadn't been expected," said the specialist, which translated into additional loading during flight. Airbus has already conducted verification flights to measure actual loading, and found that its original design calculations are correct.
(Emphasis mine.)

I read this primarily to mean "We overstressed the part and cracked it."

To say these cracks are fatigue-related, there must be an assumption of cyclic loading and unloading of the part. Furthermore, the number of cycles on this part would have to be high enough at those stresses to induce fatigue. Airbus is clearly saying that there were unanticipated stresses; what is not known is the existence of cyclic loading or the number of cycles.

Disclaimer: I have no experience assembliing wings, so I'm not familiar with whether cyclic loading is expected. I'm all ears (er, eyes) on this particular issue.
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mffoda
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Fri Jan 20, 2012 9:33 pm

Here's a piece from ATW regarding the AD and new cracks.. They are saying it is possibly more significant?

http://atwonline.com/international-a...cks-20-a380s-more-significant-0120

"EASA said in the AD that the “new form of rib foot cracking [Type 2 cracks], originating from the forward and aft edges of the vertical web of the rib feet “is more significant than the original rib foot hole cracking. It has been determined that the Type 2 cracks may develop on other aeroplanes after a period of time in service. This condition, if not detected and corrected, could potentially affect the structural integrity of the aeroplane.”
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Stitch
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Fri Jan 20, 2012 9:37 pm

Quoting mffoda (Reply 12):
Here's a piece from ATW regarding the AD and new cracks.. They are saying it is possibly more significant?

I was just reading the EASA AD and noticed that. The inspection period is also based on how many hours and cycles the plane has - four weeks for those with the higher values, six weeks for those with less.

So is EASA's concern that these other cracks might indeed be caused by the number of cycles/hours flown?
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Fri Jan 20, 2012 9:58 pm

Quoting Stitch (Reply 13):
So is EASA's concern that these other cracks might indeed be caused by the number of cycles/hours flown?

I don't really know... hopefully some of our maintenance guru's will provide some insight.

The thing I having trouble with is the reporting? (A380 wing cracks/ 747-8I fuel tanks?) When these cracks where first reported, It was no big deal (already identified by Airbus) and a plan in place to deal with it at the next heavy check?? Now must be done straight away...

How do we go from there to here in such a short period of time? Something seems out whack... Is this just damage control? Regardless if it is Airbus or Boeing?
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Fri Jan 20, 2012 10:10 pm

Quoting Stitch (Reply 13):

So is EASA's concern that these other cracks might indeed be caused by the number of cycles/hours flown?



No, sounds like they are more concerned about catching these cracks and repair them before they result in a part failure.

The number of cycles affect the crack growth and not necessarily how they start.
I have not read anything on if they have determined what is behind the most recent cracks.

The shorter inspection period on the higher time aircraft is because the crack length may be closer to critical lengths.

I didn't realize these planes have surpassed the 1000 flight cycle mark. How time flies . . .

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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Fri Jan 20, 2012 10:23 pm

Quoting mffoda (Reply 14):
When these cracks where first reported, It was no big deal (already identified by Airbus) and a plan in place to deal with it at the next heavy check?? Now must be done straight away...

Two different sets of cracks. We'll have to wait for more details to come out on the second set.

I wouldn't be surprised if everything comes down to not fully understanding some obscure crack propagation property of a new aluminum alloy. Been there . . . done that.  

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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sat Jan 21, 2012 1:50 am

Quoting Stitch (Reply 1):

So as many of us suspected, nothing to get worried over and fixes will be made for new-builds (manufacturing) and already-built planes.

I'm glad it as those of us in the industry suspected.   

Quoting ContnlEliteCMH (Reply 11):
"It's possible to get standing stresses that hadn't been expected,"

I would translate that as manufacturing related.

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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sat Jan 21, 2012 1:03 pm

Here's the link to EASA website and AD's page:

http://ad.easa.europa.eu/

And here's the link to the particular AD issued by EASA ordering wing inspections:

http://ad.easa.europa.eu/ad/2012-0013

Don't omit to read the little PDF file attached...

Here's part of the report:

"The new form of cracking is more significant than the original rib foot hole cracking. It has been determined that the Type 2 cracks may develop on other aeroplanes after a period of time in service.
This condition, if not detected and corrected, could potentially affect the structural integrity of the aeroplane."
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Ruscoe
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sat Jan 21, 2012 1:13 pm

Why weren't these cracks picked up on the fatigue test craft?

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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sat Jan 21, 2012 1:25 pm

Quoting lightsaber (Reply 17):
I would translate that as manufacturing related.

I wonder if the recent loss by GKN of some wing component work on A320 neo wings to South Korea in any way to be interpreted as "punishment" of GKN by Airbus for poor quality manufacturing in this case?
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sat Jan 21, 2012 2:39 pm

Quoting Ruscoe (Reply 19):
Why weren't these cracks picked up on the fatigue test craft?

At least the first set of cracks do not appear to be caused by fatigue, but instead by stresses imposed during manufacturing and/or installation.

I get a sense from reading EASA's ED that the second set of cracks may indeed be fatigue-based, at least in part, since they do require aircraft with higher cycles or hours to be examined quicker and note that if left unchecked, the cracks could propagate.
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sat Jan 21, 2012 5:04 pm

Quoting Ruscoe (Reply 19):
Why weren't these cracks picked up on the fatigue test craft?

One big variable between the fatigue frame and real life operation is thermal cycling and presence of fuel. While I doubt that fuel would exasperate fatigue crack growth, temperature may influence crack propagation in some metals.

Although I'm not saying that this would be the case here.  

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Ruscoe
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sat Jan 21, 2012 11:09 pm

I admit to not knowing how fatigue test frames are checked, but it seems to me that if these cracks are due to manufacturing problem or fatigue, that they would have been detected, whilst checking fatigue frame for cracks, because isn't the test frame supposed to be ahead of hours of aircraft in service.

If the 2nd type of cracks are due thermal loads then I can see why they may not appear on fatigue frame. (Is this why Boeing moved the 787 test frame outside, into the weather?)

If the test frame is not accurately predicting in service stress issues, then this is a very serious matter in my opinion.

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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sat Jan 21, 2012 11:54 pm

Quoting ContnlEliteCMH (Reply 11):
I read this primarily to mean "We overstressed the part and cracked it."

It says they overstressed the part, which lead to later cracking. If they cracked it during manufacturing it would have shown up during assembly, not hundreds of cycles into operation.

Quoting ContnlEliteCMH (Reply 11):
To say these cracks are fatigue-related, there must be an assumption of cyclic loading and unloading of the part.

It's a wing rib...cyclic loading isn't an assumption, it's a given.

Quoting ContnlEliteCMH (Reply 11):
Furthermore, the number of cycles on this part would have to be high enough at those stresses to induce fatigue.

With aluminum, there is no such thing as a stress low enough to prevent fatigue; aluminum doesn't have a fatigue limit. It will always crack eventually after enough stress and cycles. What gets you is that the number of cycles to failure is an extremely non-linear function of the stress. If you set an unaccounted for stress during manufacturing it can blow the fatigue life in terms of cycles completely out of the water.

Quoting ContnlEliteCMH (Reply 11):
Airbus is clearly saying that there were unanticipated stresses; what is not known is the existence of cyclic loading or the number of cycles.

Existance of cyclic loading is known. If you have unanticipated stresses in a cyclicly loaded part, it will screw up your fatigue life calculation.

Quoting Ruscoe (Reply 19):
Why weren't these cracks picked up on the fatigue test craft?

The fatigue airframe is usually one of the very first to be built; as a result it may not be manufactured or assembled using the same tools/methods as the production frames. If the unexpected stress is a result of manufacturing method, it might not be present on the fatigue frame.

Tom.
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sun Jan 22, 2012 5:27 am

Quoting Ruscoe (Reply 23):
If the 2nd type of cracks are due thermal loads then I can see why they may not appear on fatigue frame. (Is this why Boeing moved the 787 test frame outside, into the weather?)

No, even with the snow storm we had last week, the temperature is no where near cruise temp.

Quoting tdscanuck (Reply 24):
It says they overstressed the part, which lead to later cracking. If they cracked it during manufacturing it would have shown up during assembly, not hundreds of cycles into operation.

Unless the parts were shot peened, there will always be cracks at the machined surfaces. Inspection will only discover the detectable cracks. The ones that are not detectable will be the ones that grows. And if you don't have the crack growth properly characterized, you will run in to these types of problem.

Hopefully it's only a manufacturing error. If it's material problem, then this will get real expensive real fast.

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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sun Jan 22, 2012 6:25 am

Looks like they will be replacing these brackets on undelivered frames. Wonder if they will change material or just beef them up?
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sun Jan 22, 2012 9:36 pm

Quoting tdscanuck (Reply 24):
If you set an unaccounted for stress during manufacturing it can blow the fatigue life in terms of cycles completely out of the water.

   Hence why post manufacturing stress relief is so critical...

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Ruscoe
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sun Jan 22, 2012 10:55 pm

It's fascinating the speed with which Airbus was able to diagnose the cause, implement fixes, and when the cracking became public reassure the world that an check every four years was adequate, only to discover yet another type of cracking, which the regulatory authorities want fixed..

Is it possible, to do the things I mentioned above, quite quickly?

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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Sun Jan 22, 2012 11:57 pm

Was it quickly? Didn't the first cracks get noticed when the Quantas machine blew an engne? And how long ago was that?  
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Mon Jan 23, 2012 12:20 am

Quoting flyabr (Reply 29):

Was it quickly? Didn't the first cracks get noticed when the Quantas machine blew an engne? And how long ago was that?

It was discovered during repairs, which started quite a while after the accedent. You are forgetting the months burned in investigating the cause, then evaluating the damage, and finaly aquiring the required parts and personel to effect the repairs. Oh I'm sure in there was a healthy delay for argument over who pays how much when. You don't swing $100M repairs on "oh well someone will pay for it I'm sure"
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Mon Jan 23, 2012 12:57 am

And to Tom, if fatigue frame is or was unrepresentative of production hardware and processes as you claim, it would surely invalidate the fatigue test in my opinion. What is the point of testing and certifying via non representative hardware. pray?.
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Mon Jan 23, 2012 1:12 am

Quoting Ruscoe (Reply 28):
It's fascinating the speed with which Airbus was able to diagnose the cause, implement fixes, and when the cracking became public reassure the world that an check every four years was adequate, only to discover yet another type of cracking, which the regulatory authorities want fixed..

Is it possible, to do the things I mentioned above, quite quickly?

Planes have been cracking since day one. Loads of planes fly around with various patches here and there and everywhere. It is hard to imagine a type of cracking which the manufacturers and authorities hasn't seen a dozen times before. They have great experience in dealing with cracks. The only thing special about this cracking is that it is first time seen on an A380.
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Mon Jan 23, 2012 1:38 am

But not usually at 1800 flight cycles or less.
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Mon Jan 23, 2012 2:30 am

Quoting amicus (Reply 31):

Testing, be it fatigue or static, does not need to verify the exact configuration you are delivering. It is to verify that the analysis that you performed correlate with the testing. Thus, you have the confidence that the analysis will acurately pedict the result of any design changes.

Now if something like this happens and you have not properly pedicted it, then you will have to re-do the analysis and the testing, although it probably would not involve the whole airplane, just the relavent component.

As for the speed of incorporating the change, I can see how with the new design/release processes Airbus Engineering can get new production parts in the pipeline so quickly. Usually deciding what is the proper fix takes the longest time. Once that is done getting parts to the planes is more straight forward, specially if the parts are machined fittings which require little tooling changes.

But back to your point, will testing and analysis cover all your bases? Apparently not, as shown in this case.
Bt

[Edited 2012-01-22 18:37:56]
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tdscanuck
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Mon Jan 23, 2012 3:24 am

Quoting amicus (Reply 31):
And to Tom, if fatigue frame is or was unrepresentative of production hardware and processes as you claim, it would surely invalidate the fatigue test in my opinion.

I didn't say it was un-representative, I said it's not identical...the processes/methods used to build the very early frames may be very different than what's used for the production frames but they're *supposed* to be representative. There are typically many assembly and manufacturing methods that, done properly, will result in equivalent (i.e. representative) parts.

However, you're mis-understanding the fundamental reason you do the test in the first place. It is *not* to find out what the fatigue life or ultimate strength of the airframe actual is (that would require not just representative, but identical, structure). No aircraft in current production had its fatigue or static strength tests done on identical structure.

Quoting amicus (Reply 31):
What is the point of testing and certifying via non representative hardware. pray?.

1) It is supposed to be representative (not identical) hardware.
2) What bikerthai said...the point is the demonstrate your analysis is good. The key requirement is that what you do the analysis on the same configuration as the actual fatigue and static test frames so you can do apples-to-apples comparrison of analysis and actual results. A secondary requirement is that the fatigue and static frames be close enough that the results are transferable (i.e. you can use the same analysis methods) on the actual airframes. This is why you don't generally have to redo the fatigue or static strength tests for derivatives (stretches, shrinks, re-engines, up-weights, etc.)...you've proven the analysis methods using the static and fatigue frames so you can determine the performance of the new structure by analysis alone.

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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Mon Jan 23, 2012 3:53 am

Quoting amicus (Reply 33):
But not usually at 1800 flight cycles or less.

Hopefully not. But then I doubt that we a.nutters will know every time a small crack is found on a new A320 or B737 during its first C-check.

And a crack is a crack. It is repaired the same way whether its origin is a manufacturing fault or 30 years of abuse and 100,000 cycles.

Therefore it can hardly be surprising that A has a cure practically at the same time as the problem has been fully investigated.
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Mon Jan 23, 2012 4:12 am

Quoting amicus (Reply 33):
But not usually at 1800 flight cycles or less.

We have very little hard data on this. We might be now talking about cracking invisible to the naked eye and only detected by machine testing. Testing that happened because of the less serious cracking found on the damaged plane. These parts might have had 0 issues all the way out to when they would have normaly been subject to a detailed inspection. Nothing so far in the statements leads me to believe that there was a serious issue *today*, and in fact I would believe until more evidence is presented that the EASA is simply being overly cautious as the unknowns of these issues became too large to allow it to go uninspected for longer.

Again, I've read nothing that would leave me to believe that the A380 was in any actual danger of structural failure in flight.
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Mon Jan 23, 2012 4:39 am

Quoting XT6Wagon (Reply 37):
I've read nothing that would leave me to believe that the A380 was in any actual danger of structural failure in flight.

Absolutely correct! Such structures are designed according to the principles of failure tolerance. It means that such a single joint may break completely apart without becoming a safety issue within certified inspection periods.

That said, cracks never grow smaller over time, as well as bigger cracks are not easier or less expensive to repair. And on a new design there is good reason to play extra cautious when unexpected issues happen to show up.

(Pure speculation: I shouldn't wonder if Airbus has whispered into the ears of AESA: "Please don't let this drag on". They don't want to read about those cracks in the newspapers for the next two years or whenever the last of the birds involved will be up for a scheduled check. If I had been an Airbus manager, then I would have done exactly that).
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Mon Jan 23, 2012 6:03 am

From WSJ:

"Planes that are currently undergoing final assembly will have different brackets installed before they are delivered to customers, the spokesman said."

This tells me that though the issue may not be serious, it is serious enough to require a design change.

If they have to replace the parts for delivered aircrafts, it's going to cost a bundle.

Bt

[Edited 2012-01-22 22:13:47]
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Tue Jan 24, 2012 11:22 am

EASA: New cracks on 20 A380s ‘more significant’

http://atwonline.com/aircraft-engine...cks-20-a380s-more-significant-0121

[Edited 2012-01-24 03:24:20]
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Tue Jan 24, 2012 7:07 pm

I'd love to see a diagram of which brackets are cracking (both types of cracking) ..

I thought I saw somewhere that the manufacturing process being blamed was not the machining of the feet but the process of attaching the wing skins, however I can not locate the article. If true could it lie in the way they force the skin to match the curvature dictated by the ribs and then install fasteners creating uneven stresses instead of using an equalizing pattern?
 
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Tue Jan 24, 2012 9:17 pm

From the ATW article;

An Airbus spokesperson told ATW in a statement

"The discovery of the cracked parts—and the rapid response to this by our airline customers, regulatory authorities and Airbus—demonstrate clearly how well the safety net works in this industry"

Seems to me that the problem was discovered by accident: literally an accident (Qantas 380), and that in fact the system did not diswcover it, although it did respond.

also

"The cracks are not on the wings;"

OK "in" the wing. Is this the Airbus PR department talking not the engineers?

Maybe all new types need greater scrutiny when they enter service.


Ruscoe
 
kurbitur
Posts: 16
Joined: Fri May 07, 2010 1:39 am

RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Wed Jan 25, 2012 8:03 pm

I just read a news article about Singapore Airlines has finished reparing the cracks on one of its A380 and it is back in service...

Does anyone knows what SIA´s A380 it is ? (reg)
 
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kanban
Posts: 3642
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 26, 2012 6:25 pm

This came out today and talks about three causes for the various cracks. http://finance.yahoo.com/news/Factor...laws-caused-rb-3609671079.html?x=0

A lot of posturing however there eventually is some meat in the article. It does not mention the problem I alluded to in post #41 so I may have been mistaken.
 
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Stitch
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 26, 2012 6:58 pm

Thanks for the article. Looks like things remain well under control.   
 
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EPA001
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 26, 2012 7:11 pm

Quoting Stitch (Reply 45):
Thanks for the article. Looks like things remain well under control.   

Which is comforting for everyone involved I guess.  . And every fan of aviation.  .
 
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bikerthai
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 26, 2012 7:54 pm

Quoting Stitch (Reply 45):
"designers' choice of aluminium alloy for some of the 4,000 brackets inside the wings,"[i]

Could have happened to any one . . .   

[i]" the use of a type of bolt that strained the metal"
  

Would be interested to know the details . . .

" and a way of closing tiny gaps that put more stress on a handful of parts."

Sounds to me they could have used some "shims". 

bt
Intelligent seeks knowledge. Enlightened seeks wisdom.
 
Ruscoe
Posts: 1577
Joined: Sun Aug 22, 1999 5:41 pm

RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 26, 2012 9:12 pm

Quoting Stitch (Reply 45):
Thanks for the article. Looks like things remain well under control.
Quoting EPA001 (Reply 46):
Which is comforting for everyone involved I guess. . And every fan of aviation

Under control after the event

What needs to be addressed is why it took an (unrelated) accident to find craqcks, some of which the EASA want fixed in a very short period of time, not 4 years.

Are there significant cracks elawhere, in other parts, not showing up on the test frame.

I accept that these are teething problems, but it seems to me that all new types need more rigourous inspections until the first c checks are done.


Ruscoe
 
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kanban
Posts: 3642
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RE: Airbus Traces A380 Wing Cracks To Manufacturing Pr

Thu Jan 26, 2012 9:45 pm

Quoting bikerthai (Reply 47):
Sounds to me they could have used some "shims".


they were trying to keep the weight under control....   

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