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Merged 787 Dreamliner

Garrison

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Garrison
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So not three months after the plane was returned to service one has suffered a fire at Heathrow Airport:

Heathrow reopens after Boeing Dreamliner 787 fire

And ironically this was the very same plane that made the first commercial flight after the 787 was cleared to fly again after the last series of incidents. Has this plane got more problems than just bad battery packs?
 
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Two more 787 'Dreamliner' incidents.

Two more 787 'Dreamliner' incidents.
Fire on parked aircraft at Heathrow; no-one aboard but serious disruption to operations.
Manchester to Florida flight had to return due to currently unspecified 'technical issues'. Aircraft was unable to dump fuel and had to circle for approximately three hours; further issues with the brakes on landing.
Note the BBC story says 30 minutes circling but later interview with passenger days 3 hours.

These do not appear to be connected to prior Li battery issues.
Boeing share price is down ~7%.
 
Well that was a quick merge, sorry I didn't see the other thread.
 
BenBurch said:
When you burn through a carbon fiber shell like that, is there a repair?
Click to expand...
Depends on whether the area is subject to buckling and/or tension loads or not. If it's only in the pressure vessel load path, no problem.
Don't know the fix, otherwise--but I'm sure there is one.
 
catsmate1 said:
Two more 787 'Dreamliner' incidents.
Fire on parked aircraft at Heathrow; no-one aboard but serious disruption to operations.
Manchester to Florida flight had to return due to currently unspecified 'technical issues'. Aircraft was unable to dump fuel and had to circle for approximately three hours; further issues with the brakes on landing.
Note the BBC story says 30 minutes circling but later interview with passenger days 3 hours.

These do not appear to be connected to prior Li battery issues.
Boeing share price is down ~7%.
Click to expand...

A 787 can dump fuel, but many airliners don't have the capability. Can you just dump fuel over the UK? Or does it have to be an emergency?

The 787 problem seems to have been the toilets being inop.
 
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rwguinn said:
Depends on whether the area is subject to buckling and/or tension loads or not. If it's only in the pressure vessel load path, no problem.
Don't know the fix, otherwise--but I'm sure there is one.
Click to expand...

As I understand it, one of the benefits of the carbon fibre shell is that it is stronger than Aluminium, and there a lot less issues about panel joins. For the average plane, that never has a fire like this, it works out to be cheaper in the long run. One of the negatives is that you can't just patch it up like you can with aluminium. The integrity of the whole section is compromised by damage like this.
 
BenBurch said:
When you burn through a carbon fiber shell like that, is there a repair?
Click to expand...

Depends on where the damage is specifically. I have been working around carbon fuselages for around 10 years and they can be tricky as far as repairs go. I don't actually do that work but I have observed the crews doing them closely. And we have had several repairs that were quite large and took months to complete.
For non-critical areas there are standard repair procedures that typically involve routing out damage,followed by composite repairs using vacuum bags. This is usually followed by ultrasonic inspection for voids. Some carbon sections have a woven steel mesh embedded for grounding/lightning strike pathways.

So as you can imagine lightning strikes on composite aircraft can cause extensive damage.

Generally anything more than routine repairs will always go through engineering.
I have been surprised at the extent composites have for repair though. But one day we will see one that is beyond repair I am sure. But then again we have seen aluminum structures that were beyond repair as well. Or at least not cost effective for repair.

The 787 is basically a flying power station with a massive amount of juice and wiring. It is radically different. Great on paper...but we will see.
 
Yeah but that's over Birmingham....

Boeing did claim that this was the world's most advanced passenger jet and made a big song and dance about all the new engineering and technology so I'm not at all suprised that there are "teething" problems.
 
rwguinn said:
Depends on whether the area is subject to buckling and/or tension loads or not. If it's only in the pressure vessel load path, no problem.
Click to expand...
That's not clear to me. Can you say more without have to write a 10-page technical bulletin? I have a technical background but am not conversant with aircraft hull issues.

TIA.
 
383LQ4SS said:
Depends on where the damage is specifically. I have been working around carbon fuselages for around 10 years and they can be tricky as far as repairs go. I don't actually do that work but I have observed the crews doing them closely. And we have had several repairs that were quite large and took months to complete.
For non-critical areas there are standard repair procedures that typically involve routing out damage,followed by composite repairs using vacuum bags. This is usually followed by ultrasonic inspection for voids. Some carbon sections have a woven steel mesh embedded for grounding/lightning strike pathways.

So as you can imagine lightning strikes on composite aircraft can cause extensive damage.

Generally anything more than routine repairs will always go through engineering.
I have been surprised at the extent composites have for repair though. But one day we will see one that is beyond repair I am sure. But then again we have seen aluminum structures that were beyond repair as well. Or at least not cost effective for repair.

The 787 is basically a flying power station with a massive amount of juice and wiring. It is radically different. Great on paper...but we will see.
Click to expand...

The 787 is made up of barrel sections that are joined together. The A350, in contrast, uses the usual panels joined together, but these panels are larger than you see in an aluminium plane. I think this makes the A350 easier to repair if you just want to replace a damaged section.

The area damage would, I guess, be more critical since it is where the start of the vertical stabiliser is joined.
 
SezMe said:
That's not clear to me. Can you say more without have to write a 10-page technical bulletin? I have a technical background but am not conversant with aircraft hull issues.

TIA.
Click to expand...
I'll give it a try--I'm an aluminum guy, with limited composites experience, so ....
when you bend a beam (or a whole fuselage, in this case) up--by this meaning the ends are up wrt the middle-- the upper surface of the beam is in compression, and subject to buckling. The lower surface is in tension. The reverse is true for bending the other way.
If the bird uses the fuselage skin as part of the beam, then the area in question is in that load path. The repair will be complicated
If the area is not in that load path, then you can cut the bad out, making the hole wider to the inside (scarf cut) and insert a new panel with matching edges. The scarf cut gives a mechanical restraint to the panel, as well as the glue/rivet/whatever. Of course, you have to take care to get the electrical grounding path connected (lightning strike protection) properly, and other considerations are needed, but it's relatively simple.

According to my sources, there are fixes for the load path problem, but they are complex and take a fair amount of time..
 
LTC8K6 said:
A 787 can dump fuel, but many airliners don't have the capability. Can you just dump fuel over the UK? Or does it have to be an emergency?
Click to expand...

There is no prohibition on dumping fuel anywhere that I know about. All Jet Fuel dissipates rapidly, so none reaches the ground.

As an afterthought, why would an aircraft dump fuel in other than an emergency that required an ASAP landing? Since this was apparently not an emergency it only involved the inconvenience of passengers. That might be the reason they didn't dump.
 
Reheat said:
There is no prohibition on dumping fuel anywhere that I know about. All Jet Fuel dissipates rapidly, so none reaches the ground.

As an afterthought, why would an aircraft dump fuel in other than an emergency that required an ASAP landing? Since this was apparently not an emergency it only involved the inconvenience of passengers. That might be the reason they didn't dump.
Click to expand...

The only FAA regulations about fuel dumping are that the aircraft needs to be 2000 ft higher than the tallest obstacle within 5 miles of the route or pattern being flown.

If the aircraft exceeded it's maximum landing weight it would have to dump fuel whether there was an emergency or inconvenience to passengers.
 
Skwinty said:
The only FAA regulations about fuel dumping are that the aircraft needs to be 2000 ft higher than the tallest obstacle within 5 miles of the route or pattern being flown.

If the aircraft exceeded it's maximum landing weight it would have to dump fuel whether there was an emergency or inconvenience to passengers.
Click to expand...

Or just burn it off by flying around for as long as it takes to burn-off the excess fuel, which is what he apparently did.
 
True, I suppose it just depends on how quickly you need to land.

Do you know what the typical dump flow rate would be? I wonder if a military jet on full afterburner would burn fuel faster than dumping it?

ETA: This document says a Boeing 777 can dump up to 2000 l/min per pump. So if two dump systems 4000 l/min.

It also appears that Switzerland has stricter rules about fuel dumps.

http://www.zurich-airport.com/Porta...und_laerm/2012_Treibstoffschnellablass_EN.pdf
 
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