Byrdluvs747
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How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 7:24 am

From the first time I saw the burn marks on the Ethiopian 787, I wondered how the aircraft will be repaired. With such heat, I imagine that the resin in the CFRP barrels is damaged beyond a simple patching repair. Pressurising the cabin seems to be an issue also. So will Boeing just replace the entire section?

This also raises the question of having to fly a plane to Washington in order to do hull repairs.
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BestWestern
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 7:27 am

Simples... replace the coffee pot...



Until we know what the problem is, how can we even think of answering this question. And nobody here knows.
You are 100 times more likely to catch a cold on a flight than an average person!
 
TC957
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 7:38 am

Answer is with great difficulty. And I suspect there will be a lot of A-net threads asking the same thing over the coming weeks. We'll just have to be patient and let the investigators do their stuff first and then look out for official press releases. Unless of course, there's an a-netter amongst the investigative team who can update us....
 
 
Byrdluvs747
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 9:17 am

Quoting BestWestern (Reply 1):
Until we know what the problem is, how can we even think of answering this question. And nobody here knows.

My question has nothing to do with what caused the fire, but how to repair the resulting damage.

Quoting TC957 (Reply 2):
We'll just have to be patient and let the investigators do their stuff first and then look out for official press releases.

Yes, but the CFRP repair itself has nothing to do with any investigation. The hull is burned, what caused it to burn doesn't change how it will be repaired. Boeing should (I hope to dear god) have already have procedures in place to repair various damage to the 787s skin.
The 747: The hands who designed it were guided by god.
 
BestWestern
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 9:21 am

Quoting Byrdluvs747 (Reply 3):
My question has nothing to do with what caused the fire, but how to repair the resulting damage.

How do you expect anyone to answer your question without knowing what damage the aircraft has suffered. nobody knows what damage was done in the fire.

Its like asking how do you fix a broken down car without the person you ask knowing whats wrong with it..
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EK413
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 9:27 am

Quoting Byrdluvs747 (Reply 3):
Yes, but the CFRP repair itself has nothing to do with any investigation. The hull is burned, what caused it to burn doesn't change how it will be repaired. Boeing should (I hope to dear god) have already have procedures in place to repair various damage to the 787s skin.

Boeing have procedures in place to repair various damage caused to the B787 skin & these words came from the horses mouth "Boeing" rep during the Dreamliner tour. We shouldn't speculate as many of us have read apparently the aircraft is to be written off just like VH-OQA 'Nancy Bird' was suppose to be written off but she returned to revenue service after under going extensive repairs in SIN.
Lets wait for the final report once the investigation is complete and then I'm sure Boeing will send a team to access the damage and determine if the aircraft is repairable. We know repairs have been done on the B767 http://channel.nationalgeographic.com/channel/videos/boeing-767/ but this is a different kettle of fish.

EK8413

[Edited 2013-07-14 03:13:49]
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dtw2hyd
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 7:40 pm

Two part epoxy, fiberglass cloth and lot of elbow grease.

Or find a spare Aft. Fuselage section in South Carolina.
 
WingedMigrator
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 7:52 pm

They will just replace the crown panel   
 
JoePatroni707
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 8:01 pm

The airplane will fall under the "lemon law" and Boeing will give ET a brand new 787!   
 
northwest 777
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 8:15 pm

Quoting BestWestern (Reply 4):
How do you expect anyone to answer your question without knowing what damage the aircraft has suffered. nobody knows what damage was done in the fire.

His question doesn't require knowing what is wrong with the plane, per se. His question clearly asks if there is damage beyond what a simple 'patch' of sorts could fix (and he is clearly referring to the 'hull' itself) HOW would the Boeing need to fix it. Would they have to hack the ass end of the pig or not. I understood what he was asking, and I'm an idiot.

Now relax.
 
rfields5421
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 8:16 pm

Quoting EK413 (Reply 5):
the aircraft is to be written off

I would not be surprised to see the aircraft return to service. In fact, I would be greatly surprised to not see it flying again.

Cost would not be a factor.

Boeing and Airbus both need the plane back in the air to demonstrate repairs to the CFRP fuselage are possible after hul damage, and hopefully economic.

Otherwise both the B787 and A350 are doomed, and both companies have bet their future on those aircraft.
 
northwest 777
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 8:19 pm

For what it's worth BestWestern, that post of mine came off as snarky, and I apologize. It wrote differently and more playfully than it reads LOL. By the way, I see both you and I joined the same time, waaaaay back in September of 2000. I don't know about you, but I'm not sure if I should be proud of that, or depressed by that!
 
Klaus
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 8:34 pm

Quoting rfields5421 (Reply 10):
I would not be surprised to see the aircraft return to service. In fact, I would be greatly surprised to not see it flying again.

Indeed – Boeing's other customers require them to demonstrate the repairability of the new fuselage construction, and Boeing knows it.

There will be no writeoff if it can be helped at all. But it's probably not necessary anyway, unless the heat has crept forward all the way and seriously damaged the crown area across the entire length of the fuselage.

Quoting rfields5421 (Reply 10):
Boeing and Airbus both need the plane back in the air to demonstrate repairs to the CFRP fuselage are possible after hul damage, and hopefully economic.

Otherwise both the B787 and A350 are doomed, and both companies have bet their future on those aircraft.

Not quite – this incident is actually a strong argument for Airbus' construction with separately replaceable segments – in this case on an A350 you'd only have to replace the crown segment(s) if a patch should not be sufficient. In such a case Boeing may have to replace the entire barrel, maybe even the adjacent one as well if its structural strength is compromised enough.

The repair may be many times more expensive on the 787 than it would be on the A350 if a very large patch in this critical area is not feasible. Not great for Boeing. They will move heaven and earth to keep it below that if they can.

And if you were John Leahy, would you really fail to refer to such a 787 barrel replacement (with all the associated much more extensive disassembly / reassembly) in your repairability presentations on the A350?

This incident hands him a great argument on a silver platter.

[Edited 2013-07-14 13:34:52]
 
Wingtips56
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 8:37 pm

Have there been any genuine reports about what the damage is... ie., is is burned through, intact but scorched, interior damage, etc.? Is there damage inside the cabin? The only news items I've seen are the initial ones about the 'blaze' and then the reports that it is not attributed to the batteries, but then 90% of the article goes on and on about the previous battery incidents. Nothing about this one, like the cabin was gutted in the fire, the galley is toast, you can see daylight through the ceiling or it's all melted like the Wicked Witch. It's as if nobody has even gone inside yet.

That said, I can see the validity of the with the original post's question being how much could be done at LHR, assuming it's not flyable as is. Could they do the laminate repairs there or even take the plane apart and replace the barrel section there? If it isn't flyable and does require a section swap out, then I can see it's only fate being to cut it up and haul it away. Can it be taken apart and the sections ferried out on the DreamLifter for repair and reassembly by Boeing at PAE or CHS? I'd hate to see it become the LHR Fire Brigade's new training hull.
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Klaus
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 8:52 pm

Quoting Wingtips56 (Reply 13):
Have there been any genuine reports about what the damage is... ie., is is burned through, intact but scorched, interior damage, etc.? Is there damage inside the cabin?

Not really as far as I have seen – the earlier "coffe maker" rumour seems to have been a false lead.

Quoting Wingtips56 (Reply 13):
That said, I can see the validity of the with the original post's question being how much could be done at LHR, assuming it's not flyable as is. Could they do the laminate repairs there or even take the plane apart and replace the barrel section there? If it isn't flyable and does require a section swap out, then I can see it's only fate being to cut it up and haul it away.
BA is getting 787s anyway. They'll jump at the chance to train their maintenance at major 787 repairs right on their doorstep, and they'll have the full support of Boeing behind them.

And Boeing must have designed their repair processes to be feasible at far more sparsely equipped airports than London Heathrow.

Even if they'll have to replace entire barrel sections they'll do that on site. There should be transportable jigs for that purpose either available or designed for implementation. Even british Airbus infrastructure might be usable for some of the work.

Given that the incident happened at all, Heathrow should be close to a best case in terms of location and infrastructure.

[Edited 2013-07-14 13:54:45]
 
DTWPurserBoy
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 9:09 pm

Quoting Wingtips56 (Reply 13):
Have there been any genuine reports about what the damage is... ie., is is burned through, intact but scorched, interior damage, etc.? Is there damage inside the cabin?

I asked this same question on another thread. With the kind of heat required to damage the exterior, there had to have been considerable damage to the cabin interior from heat, smoke and water. Gutting the airframe will be expensive.

I have seen aircraft that had substantial hull damage away from a major maintenance facility. What was done then was to provide a temporary fix and the aircraft receives a special ferry permit to fly the airplane to the nearest facility capable of performing the work. BA has considerable maintenance facilities at LHR but I am not sure if they know how to repair the composite. I suppose, in theory, Boeing could fly in an entire tail assembly on one of their Belugas but marrying those two sections without the required jigs would be very difficult. IMHO the aircraft will have to be flown to South Carolina for complete repair. I am not sure how you could do a temporary repair and make the plane safe enough for a trans-Atlantic ferry flight, presumably being flown by Boeing pilots.

It will ne interesting in the coming days to see what happens.
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Stitch
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 9:25 pm

Quoting Klaus (Reply 12):
Not quite – this incident is actually a strong argument for Airbus' construction with separately replaceable segments – in this case on an A350 you'd only have to replace the crown segment(s) if a patch should not be sufficient. In such a case Boeing may have to replace the entire barrel, maybe even the adjacent one as well if its structural strength is compromised enough.

If the damage is so extensive as to require a barrel swap, if the plane was an A350 I expect they'd have to pull the two sidewall panels in addition to the crown panel. A barrel swap might also be quicker than a panel (much less a three panel) swap due to the lower number of fasteners needing removal and replacement.

Using panels to improve repairability has always struck me as a red herring. IMO, Airbus went with panels because they are very familiar with the process (in Al) and they wanted to reduce risk. I expect there was some Intellectual Property issues, as well, but even if Airbus could have done the A350 with barrels, they likely would not have.
 
Klaus
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 9:53 pm

Quoting Stitch (Reply 16):
If the damage is so extensive as to require a barrel swap, if the plane was an A350 I expect they'd have to pull the two sidewall panels in addition to the crown panel.

Why? there is no indication for that whatsoever. Heat rises up, and by all indications it is highly plausible that it remained concentrated just in the crown area above the cabin ceiling – the side panels in an A350 would most likely have remained unaffected.

Quoting Stitch (Reply 16):
A barrel swap might also be quicker than a panel (much less a three panel) swap due to the lower number of fasteners needing removal and replacement.

Possible. But the structural re-certification would be at least as strenuous, plus all installations below the crown panel would have to be swapped over or be completely replaced vs. nothing to be done there on the A350 beyond reconnecting just everything actually attached to the crown panel.

Quoting Stitch (Reply 16):
Using panels to improve repairability has always struck me as a red herring. IMO, Airbus went with panels because they are very familiar with the process (in Al) and they wanted to reduce risk. I expect there was some Intellectual Property issues, as well, but even if Airbus could have done the A350 with barrels, they likely would not have.

Do you really think replacing at least the tail section if not possibly even the barrel in front of that as well due to the damaged join would be cheaper, quicker and easier than swapping in one or two new crown panels on an A350?

I have some difficulty believing that.

You may get some cost savings in production (somewhere down the road) and some weight savings from the whole barrel construction, but this incident looks to be close to a worst case regarding repairability compared to the alternative.
 
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EK413
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 9:56 pm

Quoting rfields5421 (Reply 10):
Quoting EK413 (Reply 5):
the aircraft is to be written off

I would not be surprised to see the aircraft return to service. In fact, I would be greatly surprised to not see it flying again

I never said the aircraft is to be written off. Various forums have made the claim & personally I believe the aircraft will be repaired just like QF A380 VH-OQA 'Nancy Bird'.

EK8413
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olliejolly
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 10:04 pm

I guess if ET still have the receipt they can just send it back, I guess Boeing wouldn't pay for the postage & packaging but perhaps the airline could make a deal with Royal Mail as it would be some nice publicity for them.


Really though, I wondered this myself when I first saw it, because while it isn't "terminal" looking damage, it certainly looks non-airworthy, however I'm sure that things will already be in motion with regards to how ET will have it fixed, because I highly doubt the aircraft would be written off, especially with it being so new.
 
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Stitch
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 10:08 pm

We have yet to confirm that the fuselage was actually opened to the elements. It's been suggested that what people are calling "holes" are actually just paint charring and the structure is still intact. The thickness of the stringers may very well have reduced the thermal transfer to the paint sufficiently to prevent it from being as charred.

[Edited 2013-07-14 16:04:16]
 
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EK413
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 10:09 pm

Quoting OllieJolly (Reply 19):
I highly doubt the aircraft would be written off, especially with it being so new.

New aircraft have been written off in the past.


A340-642(HGW) MSN 0856 [F-WWCJ] [EY]



EK8413

[Edited 2013-07-14 15:11:18]
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Viscount724
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 10:25 pm

Many aircraft have been repaired and returned to service after far more apparent damage than the ET 787.

A TWA 707-331B had the complete cockpit/nose section destroyed in a terrorist bombing at Damascus, Syria in 1969 after the aircraft was hijacked there on a flight from FCO to TLV. A Boeing team flew in a new nose section and repaired the aircraft and it spent another decade or more in TWA service.

Others that come to mind include the AC (still TCA then) DC-8-54F combi that was seriously damaged in a high speed rejected takeoff at LHR in 1963. It overran the runway by about 2,000 feet. A Douglas team repaired the aircraft over the next several months in a BOAC hangar at LHR.

There was also the JAL DC-8-62 that landed in San Francisco Bay about 2 miles short of the runway in 1968. It was repaired by UA and spent another 30 years or more in service, including many years as a freighter after JAL retired it.

There was also the JAL 747-200 that was blown off a snow-covered taxiway at ANC in 1975 and slid backwards down an embankment. A Boeing team also repaired that aircraft on-site in the open air. I recall at the time Boeing said it was their largest-ever on-site repair job.
 
BrianDromey
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 10:31 pm

To be fair that EY bird was broken pretty cleany in two, with untold stresses on the fuselage.

Probably the best example of an entire "barrel" or section being replaced is N862RW, which was involved in a runway overrun and had its entire front fuselage replaced in CLE.
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JoeCanuck
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 10:33 pm

CFRP is just a building material...it's not voodoo. It's been used in aerospace for decades and has been repaired since its first ding.

While this may require more extensive repair than many other incidents, bigger repairs aren't impossible repairs. They can splice in stringers and use as much fuse sheet material as required. Splicing composite parts has been done forever.

Worse structural repairs have been done to aluminum aircraft and other composite structures...just not on a 787.

I'm really very surprised at the amount of 'how will Boeing fix/maintain the dreaded CFRP bits' fear mongering that takes place whenever anything brushes up against a 787.

They'll take as much skin, stringer bits, adhesives and fasteners as required to do the job and in the end, nobody will ever be able to tell it was ever injured at all.

The real important question is not, 'how will they fix it?', but 'how did it start?'...that's the worrying bit.
What the...?
 
Klaus
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 10:35 pm

Quoting Stitch (Reply 20):
As such, the actual repair may just be some additional reinforcement patching underneath the affected area and a fresh respray of the area.

Is it really plausible that the structural integrity of the CFRP could have remained intact enough (particularly the resin component) even with the paint charring to black on the outside to allow that, and that in a critical area like this?
 
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flylku
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 10:37 pm

Sorry, cannot resist, and given what we know this answer is as good as any other: with 500 knot aviation grade duct tape.
...are we there yet?
 
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Stitch
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RE: How Will The Ethiopian 787 Be Repaired?

Sun Jul 14, 2013 11:09 pm

Quoting Klaus (Reply 25):
Is it really plausible that the structural integrity of the CFRP could have remained intact enough (particularly the resin component) even with the paint charring to black on the outside to allow that, and that in a critical area like this?

At this point t's no more or less probable than suggestions that the CFRP has been irrevocably and irreparably damaged considering we have no data to work from and are all just wildly speculating.
 
Klaus
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RE: How Will The Ethiopian 787 Be Repaired?

Mon Jul 15, 2013 12:17 am

Quoting Stitch (Reply 27):
At this point t's no more or less probable than suggestions that the CFRP has been irrevocably and irreparably damaged considering we have no data to work from and are all just wildly speculating.

The external part of the damage is visible – and quite a few properties of materials involved are known. It's not entirely speculation (apart from that being one of the main purposes of this site anyway).
 
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DocLightning
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RE: How Will The Ethiopian 787 Be Repaired?

Mon Jul 15, 2013 12:36 am

Quoting Stitch (Reply 16):
Using panels to improve repairability has always struck me as a red herring. IMO, Airbus went with panels because they are very familiar with the process (in Al) and they wanted to reduce risk.

Transport is also easier, and smaller autoclaves can be used.

Quoting EK413 (Reply 21):
New aircraft have been written off in the past.

That was an extreme situation with damage to just about every segment of the airframe. The tail was banged up, the wing was damaged, the front end absolutely destroyed. I think the only part of that airframe that was unscathed was the tailfin... there was more damaged plane than undamaged plane. This 787 could have damage to the entire crown from nose to tail and still be cheaper to fix than to replace.
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DocLightning
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RE: How Will The Ethiopian 787 Be Repaired?

Mon Jul 15, 2013 5:08 am

Quoting Stitch (Reply 16):
Using panels to improve repairability has always struck me as a red herring. IMO, Airbus went with panels because they are very familiar with the process (in Al) and they wanted to reduce risk.

Transport is also easier, and smaller autoclaves can be used.

Quoting EK413 (Reply 21):
New aircraft have been written off in the past.

That was an extreme situation with damage to just about every segment of the airframe and it was among the last A340s to be built. The tail was banged up, the wing was damaged, the front end absolutely destroyed. I think the only part of that airframe that was unscathed was the tailfin... there was more damaged plane than undamaged plane. By contrast, this 787 could have damage to the entire crown from nose to tail and still be cheaper to fix than to replace. There are something like 60-70 frames in operation world-wide and the type has an enormous backlog. Add to that the non-numerical reasons involving the emotional response to writing off a frame so early in the program. It's not a question of will they fix it, but [i]can[/i[ they fix it?
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Skydrol
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RE: How Will The Ethiopian 787 Be Repaired?

Mon Jul 15, 2013 7:21 am

White spray paint.

This way passengers will never see any burn damage evidence from the departure lounge, prior to boarding this airplane.




LD4
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zeke
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RE: How Will The Ethiopian 787 Be Repaired?

Mon Jul 15, 2013 10:07 am

Quoting Byrdluvs747 (Thread starter):
With such heat, I imagine that the resin in the CFRP barrels is damaged beyond a simple patching repair. Pressurising the cabin seems to be an issue also. So will Boeing just replace the entire section?

The change of composite which are exposed to extreme heat like this called pyrolyzation. It can lead to composite fibers being exposed that are normally within a resin matrix. If this has happened, it will complicate the investigation and repair as these fibers are considered hazardous to human health without the correct protective equipment.

As this event did not occur during operation, it was parked at a remote stand, it could not really be classified as an aircraft accident. Therefore I would suggest it would be given a lower priority for investigation by the AAIB. However it is a new type design, so it may attract some attention as it would be the first composite air frame of its size to suffer a widespread heat source on the inside.

The type of repair that will be performed will in part be a function of what equipment and skills are available in LHR to perform large scale composite repairs, the location and type of damage that exists inside the cabin, and the loads that are seen in the area.

It is possible that the damage transcends a join in the barrel. We need to keep in mind that the fiber placement in the barrel is not unidirectional, it is tailored to suit loads in the area. Typical composite repairs which involve the removal of an area of composite, or a wet layup of new composites over this area may not be effective due to the load path to be preserved, and the possibility of pyrolyzation on underlying layers making the matrix bonds less effective.

In many ways if this was a metallic structure it may be easier to repair, the tail removed (to unstress the area), support the area in a makeshift jig, removed the damaged interior, remove the old skin panels, removed damaged stringers, repair the interior, much like a tail scrape repair is done today. Most of the work we have seen relating to 787 damage tolerance was in relation to ground equipment hitting the air frame, dropping of tools, and drop testing of the fuselage. Larger areas of heat damage are hard to develop a generalized repair for.

Doing a damage tolerance assessment of the repair could well be the hardest part of trying to work out if they should replace, fix, or scrap the air frame.

The interior parts that maybe damage are possible also too large to enter via the normal doors, from a logistics point of view, it might be just as easy to remove the aft pressure bulkhead in order to place new overhead ducts, galley, stringers, frame etc.

We have very little information on the extent of the damage on the inside, we can only guess by the amount of heat needed to cause the paint to change color on the outside. The heat damage may have found easy paths to spread through the aircraft like the air ducts, and may have been accelerated with passenger oxygen system.
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Goldenshield
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RE: How Will The Ethiopian 787 Be Repaired?

Mon Jul 15, 2013 10:44 am

Well, if the airline can't repair it, send in this guy! He's been repairing composites for years!

http://www.alphazulucomposites.com/
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davidho1985
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RE: How Will The Ethiopian 787 Be Repaired?

Mon Jul 15, 2013 2:30 pm

I believe this 787 will be repaired at any cost (even it is much more expensive than replace it with a new one).

With the past incidents, both Boeing and the 787 itself can't afford a brand-new 787 being written-off at this monent.
It will be a huge discaster to them.

Same case as QF's 744 which overrun at Bangkok and their A380.

[Edited 2013-07-15 07:31:30]
 
nomadd22
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RE: How Will The Ethiopian 787 Be Repaired?

Mon Jul 15, 2013 3:23 pm

They could always start cutting patches for repairs like this out of LN003.
Anon
 
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bikerthai
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RE: How Will The Ethiopian 787 Be Repaired?

Mon Jul 15, 2013 6:54 pm

Even though the barrel is one "spunned" unit, the frames are not. It is logical that any large area repair will start at the frame splice.

The barrel skin can be cut and spliced as needed.

My guess is if they are to replace the crown area. They will fab a new crown skin section. They will replace as many frames as needed and bolt on the new crown in a similar way they did the mod with the 737 Wedgetail aircraft.

Repairing a composite crown will be more difficult than repairing an aluminum crown because you will have to have your dimension more closely matched in CFRP than you would with an aluminum panel. The drilling on CFRP would require sharper bits and you will be using bolts instead of rivets.

This is all generalization. We will have to wait and see how this specific situation will be resolved.

bt
Intelligent seeks knowledge. Enlightened seeks wisdom.
 
CaptainKramer
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RE: How Will The Ethiopian 787 Be Repaired?

Mon Jul 15, 2013 8:46 pm

I would be very surprised if the investigation by the AAIB of the Ethiopian B787 incident at LHR is not given the highest priority, given the aircraft's history and the nature of the incidents prior to this latest one.

They don't owe it to Boeing, or the various tiers of Suppliers, or the Airlines that use it, but they do owe it to the Passengers, Pilots and Cabin Crew, who with each passing day of the Aircraft's operation, take on the role of Guinea Pigs.

As regards the question of whether to fix or not to fix, if the will is there, and enough cash, anything is possible. I just wish Boeing would do the same with regards the whole B787 Program, thankfully they have dodged a bullet, so far. It's not too late.

However if the Space Shuttle Program and the first Challenger Accident that NASA failed to draw lessons from to prevent the second Columbia Accident is anything to go by, then I don't hold much hope with Boeing in the short term, as I observe the same culture of "Normalising of the Abnormal" that crept into NASA, creeping into Boeing, specifically regarding the "All Electric B787".

I just hope no Passengers, Pilots and Cabin Crew have to pay the ultimate price, as they have done so many times in the past with other "Technological Revolutions", to find a lasting solution to the B787's ongoing issue's.
 
a380900
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RE: How Will The Ethiopian 787 Be Repaired?

Mon Jul 15, 2013 10:18 pm

Quoting Wingtips56 (Reply 13):
It's as if nobody has even gone inside yet.

I'm sure info and pics about this one are a closely guarded secret. I'd be surprised if Boeing opted for the "transparency mode" regarding the 787. Too much transparency could well mean more grounding. And I don't think grounding is part of the equation anymore. I'd be surprised if the 787 got grounded again without fatalities involved. Boeing is all in now. Make or break.

Quoting CaptainKramer (Reply 37):
However if the Space Shuttle Program and the first Challenger Accident that NASA failed to draw lessons from to prevent the second Columbia Accident is anything to go by, then I don't hold much hope with Boeing in the short term, as I observe the same culture of "Normalising of the Abnormal" that crept into NASA, creeping into Boeing, specifically regarding the "All Electric B787".

As I say. The train has left the station. There won't be any more grounding of this plane unless there are fatalities. Let's hope it does not come to that.
 
Klaus
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RE: How Will The Ethiopian 787 Be Repaired?

Tue Jul 16, 2013 1:07 am

Quoting A380900 (Reply 38):
And I don't think grounding is part of the equation anymore. I'd be surprised if the 787 got grounded again without fatalities involved. Boeing is all in now. Make or break.

You think that the authorities would just let a plausibly dangerous design defect slide now? I think it's rather the opposite: Doing that would directly expose the person and the organisation signing off on such a defect to the full responsibility for any ensuing fatalities.

I'm quite certain that another grounding would only happen after exhaustive examination of all pertinent facts, but I have no doubt that it would be done if necessary, major pain for Boeing or not.

I just don't think that anything we actually know at this point really suggests that to be the likeliest outcome of the ET 787 incident.

But that Boeing staff and management are sweating bullets right now is pretty much a given.
 
LTC8K6
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RE: How Will The Ethiopian 787 Be Repaired?

Tue Jul 16, 2013 1:42 pm

http://www.bizjournals.com/seattle/n...-known-787-hull-repair-easier.html

Boeing was apparently able to fix a hole punched in the hull of a 787 by a catering truck.
 
a380900
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RE: How Will The Ethiopian 787 Be Repaired?

Tue Jul 16, 2013 2:30 pm

Quoting Klaus (Reply 39):
You think that the authorities would just let a plausibly dangerous design defect slide now?

In a word: yes. I do not trust the authorities to make the right calls at this point. Put another way: I won't fly on this aircraft in the next few years (if I trusted the authorities, obviously, I would). I think the pressure is too intense.
 
Klaus
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RE: How Will The Ethiopian 787 Be Repaired?

Tue Jul 16, 2013 2:34 pm

Personally, I can see your point, but I still don't think that anybody would knowingly sign off on a dangerous defect especially now.
 
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bikerthai
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RE: How Will The Ethiopian 787 Be Repaired?

Tue Jul 16, 2013 6:55 pm

Quoting LTC8K6 (Reply 40):

Good to hear. Would like more details.

The article mentioned heat cure. But I thought that Boeing say that a bolted repair is still an option with the composite fuselage.

bt
Intelligent seeks knowledge. Enlightened seeks wisdom.
 
LTC8K6
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RE: How Will The Ethiopian 787 Be Repaired?

Tue Jul 16, 2013 7:29 pm

Quoting bikerthai (Reply 43):
The article mentioned heat cure. But I thought that Boeing say that a bolted repair is still an option with the composite fuselage.

There's another article on repairing the 787.

http://www.compositesworld.com/artic...-composite-repair-builds-on-basics
 
JHwk
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RE: How Will The Ethiopian 787 Be Repaired?

Tue Jul 16, 2013 10:50 pm

It's not that hard to repair the damage. The hard part is to repair it with minimal additional weight. You could add a whole new aluminum frame inside the crown to transfer load around the damaged portions if you wanted to, although it is unlikely you would need to.

In all reality, repair of the damage is likely almost identical to what Airbus would do on a 350. Either way you are taking apart the interior to access the structure, doing ultrasonic or xray imaging of the damage, cutting out whatever needs to be removed, etc.

It is hard for me to believe they would ship in a new tail section. If that is really what it takes to repair it, you have substantial life-cycle issues to deal with...
 
Klaus
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RE: How Will The Ethiopian 787 Be Repaired?

Tue Jul 16, 2013 11:30 pm

Quoting JHwk (Reply 45):
In all reality, repair of the damage is likely almost identical to what Airbus would do on a 350.

Unless a local patch was not enough due to size and location – then it would just be a top panel in an A350 contrary to an entire barrel section for the 787. Or two of each if the damage extends across the section join.

Quoting JHwk (Reply 45):
It is hard for me to believe they would ship in a new tail section. If that is really what it takes to repair it, you have substantial life-cycle issues to deal with...

Wouldn't that actually be the best case regarding weight and longevity? It would simply reset the service life of the tail section with zero penalty, wouldn't it?

Contrary to a patch which would increase weight and impose extra inspections for the rest of its service life, which could be shortened simply by the financial consequences if not by structural ones.

[Edited 2013-07-16 16:31:53]
 
JoeCanuck
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RE: How Will The Ethiopian 787 Be Repaired?

Wed Jul 17, 2013 5:56 am

CFRP is not terribly different than fibreglass. In this case, it probably won't be laid up in place but will be repaired with a CRFP skin patch....of whatever size is required, with the fibers laid up much like the original skin. All of the damage will be cut out and enough to blend the new skin into the old. On the backside, pre formed stringers will be cut to length and spliced in.

To be extra careful, they will probably build up the spices more than they need to and may even use metal fasteners in some places.

This is basically one way composite repairs have been done since there ever was plastic composites. The 'CF' bit of CFRP, is most of the strength and the 'RP' basically holds the fibres in whatever shape is required.

Sailplanes, boats, race cars and other airliners, (the 380 being a very big example), have been using and repairing CRFP, largely without problem.

Why the 787 should suddenly be the fly in the ointment for these materials is far beyond my obviously inadequate powers of perception.

Anything that's obviously burned, they'll cut out and replace. Anything they suspect is burned or compromised in any way, they'll cut out and replace.

I'm curious about their repair techniques because I'm a geek, not because I think it'll be technologically difficult or that tha plane will be unsafe to fly on after being repaired.

ps....I think exactly the same thing for the 350.
What the...?
 
o0OOO0oChris
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RE: How Will The Ethiopian 787 Be Repaired?

Wed Jul 17, 2013 9:10 pm

 
JHwk
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RE: How Will The Ethiopian 787 Be Repaired?

Thu Jul 18, 2013 3:49 am

Quoting Klaus (Reply 46):

The life cycle issues I was referring to are fleet-wide, not this airframe. JoeCanuck did a much better job than I on explaining the process (about how I envision it would happen as well). They might need to add some extra stiffeners into the mix (or engineer the stringers to do the function), but it really isn't that big of a deal.

Airbus would likely never replace a whole panel either; all fasteners would need to be removed, the existing panel removed, and the new panel installed and fixed in place. Why do that when a patch can match the integrity of the installation. Flying in a new barrel section solves nothing for Boeing, unless the whole tail was really damaged.

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