Japan runway crash marks test of how new carbon jets cope in a disaster

[BlankBox]

WASHINGTON/LONDON - The runway collision in Japan on Jan 2 (https://www.straitstimes.com/asia/east-asia/aircraft-on-fire-at-tokyo-haneda-airport-reports) marks the first time a modern lightweight airliner has burned down and is being seen as a test case for how well a new generation of carbon-composite planes copes with a catastrophic fire.

The crash "is really the first case study that we have, not only from a fire perspective, but also just from a crash survivability perspective", said Anthony Brickhouse, an air safety expert at Embry-Riddle Aeronautical University.​​​​​​​

https://www.straitstimes.com/asia/japan-crash-marks-test-of-how-new-carbon-jets-cope-in-a-disaster

[ZFT]

https://www.straitstimes.com/asia/japan-crash-marks-test-of-how-new-carbon-jets-cope-in-a-disaster
Lots of 'experts' being quoted but what constitutes an expert? Anyone with an opinion it seems.

[Chronic Snoozer]

Lots of 'experts' being quoted but what constitutes an expert? Anyone with an opinion it seems.

Well quite obviously, "expert" constitutes two parts - "ex", meaning 'has-been' and "spurt", meaning 'drip under pressure'.

[nonsense]

Lots of 'experts' being quoted but what constitutes an expert? Anyone with an opinion it seems.

I think the point of the article is that until now there has been very limited data from which to develop expertise?

[DaveReidUK]

The crash "is really the first case study that we have, not only from a fire perspective, but also just from a crash survivability perspective", said Anthony Brickhouse, an air safety expert at Embry-Riddle Aeronautical University.

Great name for someone who studies strength and fire resistance. :O

[safetypee]

"… first time …"

See: Flight 358, A340, 2 August 2005, Toronto Airport, Canada.

https://en.wikipedia.org/wiki/Air_France_Flight_358

Similarities, but 'safe'; time - effect relationship was sufficient for evacuation.
Pprune discussion at that time speculated contribution of independent oxygen generators in cabin overhead.
But not to overlook fuel from the aircraft(s) damage as the accelerant.

N.B. Wings / fuel tanks intact.
What are the structural / material differences between cabin and wing.


https://cimg6.ibsrv.net/gimg/pprune.org-vbulletin/1600x506/img_0296_bf1decc2367df8a418e323ae1ba1e8861142bb8f.jpeg

Edit: and B777
https://en.wikipedia.org/wiki/Asiana_Airlines_Flight_214

https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/1920x1280/img_0297_5d0498b7c47386d1c0dc27fb3b0c7c4755ef95c3.jpeg

[tdracer]

I think there will be a great deal of study of this accident and to how well the carbon composite construction held up compared to what could have been expected of aluminum - both for fire protection and for the effect of the impact with the Dash 8.

That being said, at least according to a Wall Street Journal article - it took nearly 18 minutes (from initial impact) before the aircraft was full evacuated. Sounds like the carbon composite fuselage held up as pretty well...

[safetypee]

Flammability Properties of Aircraft Carbon-Fiber Structural Composite

https://www.fire.tc.faa.gov/pdf/07-57.pdf

https://en.m.wikipedia.org/wiki/Los_Angeles_runway_disaster

Everyone already out

https://cimg1.ibsrv.net/gimg/pprune.org-vbulletin/800x600/img_0301_239f8d9f878a9b69f0ab093e5f8fe7fe6ef01e1a.jpeg

[unmanned_droid]

How do you investigate a few buckets of carbon shards?

[Lomon]

That being said, at least according to a Wall Street Journal article - it took nearly 18 minutes (from initial impact) before the aircraft was full evacuated. Sounds like the carbon composite fuselage held up as pretty well...

It is a bit disingenuous quoting the evacuation took 18 minutes. According to this report https://theaircurrent.com/feed/dispatches/japanese-tv-reconstructs-jal-a350-evacuation-from-passenger-footage/ 11 minutes of that time was the captain making 100% sure there was no-one left on the aircraft before he "abandoned ship" himself. If that is true, then everyone (bar the captain) was off in 7 minutes.

[RatherBeFlying]

Aluminum vs Carbon Fiber Epoxy in Fire Aluminum has a low melting point compared to many other metals; so offers little shielding to fuselage components. Carbon fiber with epoxy in this case seems to have held up longer.

I am wondering if a 777 in the same situation and evacuation duration would have had as good a passenger survival outcome.

Whatever is burning, the combustion products are toxic and incapacitating. Survivors of smoke inhalation may end up with reduced lung function and shortened lifespans. Firefighters typically have few years post retirement.

[45989]

Well quite obviously, "expert" constitutes two parts - "ex", meaning 'has-been' and "spurt", meaning 'drip under pressure'.
Brilliant! Too True though:D:D:D

[tdracer]

It is a bit disingenuous quoting the evacuation took 18 minutes. According to this report https://theaircurrent.com/feed/dispatches/japanese-tv-reconstructs-jal-a350-evacuation-from-passenger-footage/ 11 minutes of that time was the captain making 100% sure there was no-one left on the aircraft before he "abandoned ship" himself. If that is true, then everyone (bar the captain) was off in 7 minutes.
You totally missed the point of that statement!
There were 18 minutes between impact (where the fire started), and the point where the aircraft was fully evacuated. The point is not that it took 18 minutes, it's that the fuselage provided protection from the fire for 18 minutes! Never did I question why it took that long - there is plenty of that going on in the existing thread in the accident forum.

18 minutes is pretty damn good - as others have speculated, I doubt aluminum would have held up that well for that long...

As I posted, there will be no shortage of study of how the carbon composite construction fared, compared to conventional aluminum (as well as ways both could potentially be improved). During the development stage of the (similarly constructed) 787, there was plenty of nay-sayer speculation that carbon composite wouldn't provide the same level of protection as aluminum in an accident - my initial impressions from this accident say those critics were rather dramatically wrong...

[Lomon]

You totally missed the point of that statement!
There were 18 minutes between impact (where the fire started), and the point where the aircraft was fully evacuated. The point is not that it took 18 minutes, it's that the fuselage provided protection from the fire for 18 minutes! Never did I question why it took that long - there is plenty of that going on in the existing thread in the accident forum.

18 minutes is pretty damn good - as others have speculated, I doubt aluminum would have held up that well for that long...

As I posted, there will be no shortage of study of how the carbon composite construction fared, compared to conventional aluminum (as well as ways both could potentially be improved). During the development stage of the (similarly constructed) 787, there was plenty of nay-sayer speculation that carbon composite wouldn't provide the same level of protection as aluminum in an accident - my initial impressions from this accident say those critics were rather dramatically wrong...

It wasn't necessarily a dig at you or anyone on the forum, but more the way the media is portraying the time taken for the evacuation - as if 18 minutes was a long time to get 379 people off an aircraft rather than the triumph and bravery that was getting all the passengers and crew off in 7 minutes and then spending another 11 minutes in a burning airframe checking to be 100% sure that everyone they were responsible for had been safely evacuated.

[safetypee]

See link; early signs of fire inside the cabin.
Plastic windows melt before structure ?
Note internal smoke hazard.

Also note outcome fire pattern appears to be top-down from the roof (several aircraft), which might further indicate an inside-out fire.

[How many mobile lithium batteries remained on board - an intense fire might only require one to sustain it?]

https://www.pprune.org/accidents-close-calls/656665-jal-incident-haneda-airport-49.html#post11570942

Re; "passengers and crew off in 7 minutes" … after the aircraft was stationary. Evacuation timings are normally assessed from the moment that the crew command an evacuation; i.e ignores time before-hand required to understand the situation and decide to evacuate.

[DogTailRed2]

How do operators survive these accidents? That's a considerable dollar loss to recuperate, or is the hull fully insured?

[NutLoose]

I would be very very careful, I remember a Harrier crash in Germany and it burnt, the crash team were walking around kicking up dust and inhaled the fibres that literally shredded their lungs.

[island_airphoto]

How do operators survive these accidents? That's a considerable dollar loss to recuperate, or is the hull fully insured?
Insurance went up for pretty much anything that flies thanks to the Boeing Max crashes, so it seems like they all have insurance ;)

[SOPS]

How do operators survive these accidents? That's a considerable dollar loss to recuperate, or is the hull fully insured?

Is that a serious question? I miss when this forum was for professional pilots.

[swh]

Everyone already out



Have another look in the cockpit, they were last to leave 18 minutes after landing.

[Good Business Sense]

Insurance went up for pretty much anything that flies thanks to the Boeing Max crashes, so it seems like they all have insurance ;)

Yep .....and we'll all (virtually all operators of all sizes) get an increase in insurance costs on the back of this next year.

[DIBO]

How do operators survive these accidents? That's a considerable dollar loss to recuperate, or is the hull fully insured?
Nontheless the insurance,
"Japan Airlines (JAL) has said it expecting to report an operating loss of Y15bn ($104m) as a result of the collision between one of its A350 aircraft and a coastguard plane at Haneda airport."

[tdracer]

Nontheless the insurance,
"Japan Airlines (JAL) has said it expecting to report an operating loss of Y15bn ($104m) as a result of the collision between one of its A350 aircraft and a coastguard plane at Haneda airport."
The airframe is covered by insurance. The disruption costs, the costs to take care of the passengers (and their baggage, etc.), PR and reputational damage, etc. - that all falls outside the scope of the airframe insurance.
Plus, a replacement aircraft will likely significantly more than what they get from the insurance...

[xyze]

I think the interesting and novel thing about this accident is the fact that the roof of the fuselage did not disintegrate the way aluminum would - see pics of the AF and Asiana birds above and many others e.g.

https://cimg9.ibsrv.net/gimg/pprune.org-vbulletin/727x301/2_bf22afb0349925fbf6d421740950f31053042bbc.jpg


in which there has been an intense cabin fire (even of relatively short duration). What seems to have happened is that once inside the fuselage (getting in from below) the fire was retained within it without breaching the roof. All those pictures of the fire in which there is a raging fire inside and along the length of the cabin as seen through the windows and doors without the roof having gone are a first - at least for me.

https://cimg4.ibsrv.net/gimg/pprune.org-vbulletin/711x381/1_45ff8493a236c02f930f73335da08575a0ea6dba.jpg

Usually by the time the fire inside is that advanced and intense, the roof has melted away and the flames can be doused before the lower half of the plane is destroyed. I wonder if in this case the intact roof prevented the effective control of the fire, leaving the fire crews to simply watch as the burning cabin floor melted and sank into the baggage compartment (while still fully/partially covered by a sagging roof) and continued to burn until the fuselage was the complete melted wreck seen the next day. I also wonder if melted masses of plastic/carbon have made it hard to find the CVR - which as far as I am aware has still not been found.

[meleagertoo]

I don't think it makes much if any difference what the materials are, once a fire has taken hold inside the cabin no amount of external water/foam can have any effect whatsoever except for boundary cooling. Unless you can achieve foam delivery inside it's just going to run off the fuselage onto the ground.
Sure, fight external fire with every effort to prevent burnthrough, but if/once that occurs you've lost the battle, and with the massive damage in the belly of this aircraft the hull's integrity may well have been compromised anyway.
I suspect we're going to be hearing a good deal about the health hazards of burned carbon fibres too, an issue that's barely been raised so far. Removal and disposal of the wreckage will be a difficult business, especially if there is any wind at all.

[Germaine]

When comparing alluminium fuselage structure to composite, I would have thought one of the most important measures is how long it takes an external fire to breach an undamaged fuselage. I appreciate the fuselage of the A350 at Haneda may have been anything but undamaged, however, it seemed to stand up reasonably well to the extenal blaze. I am not in any particular composits vs alluminium camp here, although, to make a comparison with the Manchester 737 disaster in the 80's, it according to wiki, it would seem that fire burned through the fuselage in less than a minute, and last survivor was removed by fire crew after 5.5 minutes. However, this was a big fuel fed fire with the hot side into wind, so admittedly, a different scenario.
Disclaimer: lurking SLF here, no aircraft industry knowledge apart from a knowledge of what burning composite smells like having done ultrasonic bonding trial for the industry.

[RichardJones]

Plastic burns well. Heating plastic in a super heated "oven", and condensing the gas given off, produces petrol. (pyrolysis)

I did question, on JB the consumption rate of the burning fuselage. I was told to keep out of it and leave it to the proffesionals on pprune . My response to the expert, was removed by the moderator.

[Germaine]

Plastic burns well. Heating plastic in a super heated "oven", and condensing the gas given off, produces petrol.

I did question, on JB the consumption rate of the burning fuselage. I was told to keep out of it and leave it to the proffesionals on pprune . My response to the expert, was removed by the moderator.
Maybe, but CF laminate does not burn like plastic, i do know this from experience, components I used to clamp the laminate started to burn due to energy transmission tbrough the laminate from the ultrasonic source, but not the CF. Additionally, the A350 seemed to hold up pretty well.

[Ninthace]

Plastic burns well. Heating plastic in a super heated "oven", and condensing the gas given off, produces petrol. (pyrolysis)

Interested to know what you think "petrol" is in this context. Could you run a car on it?

[RichardJones]

Interested to know what you think "petrol" is in this context. Could you run a car on it?

Yes you can I am informed and believe. If you can produce sufficient quantities. Petroleum spirit.
However, being realistic, the energy involved in heating the stuff, would be greater then the energy produced,in petrol.
I raised this, to illustrate the volatility of some of these composite materials.

[Germaine]

Yes you can I am informed and believe. If you can produce sufficient quantities. Petroleum spirit.
However, being realistic, the energy involved in heating the stuff, would be greater then the energy produced,in petrol.
I raised this, to illustrate the volatility of some of these composite materials.
Do you think thst volitility was on display with the post crash fire of the A350? I would say, (as another poster already observed) that the fire resilience of the A350 actually thwarted the fire fighters dealing with what became an internal blaze, o
n an alluminium aircraft the fuselage roof would typically melt and burn quite quickly, The A350 didnt seem to do that, consequently, the fire fighters couldnt douse the flames.

[Germaine]

To add to this.... A quick google indicated that CF Laminate has a melt point of over 3000c while alluminium melts at 600c and burns at 1000c. Disclaimer: Google "fact" accuracy not guaranteed!