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-   -   Ethiopean 787 fire at Heathrow (https://www.pprune.org/engineers-technicians/518971-ethiopean-787-fire-heathrow.html)

alisoncc 14th July 2013 08:12

TWT, I am aware of that. Never suggested it had anything to do with the battery per se, but as the cause of the battery malfunction has never been accurately determined, and this fire seems to be when the aircraft is undergoing similar activity, namely towing related, there could be some connection.

joy ride 14th July 2013 08:16

"no evidence of a direct causal relationship"

I fully understand that this needs to be investigated thoroughly and this will take time, but this carefully loose phrase does not reassure me about the entire battery and electrical system.

Add to this the fact that Boeing seems to have declined strong advice to insulate the roof structure, and that the Manchester 787 had electrical faults relating to toilets and galleys all leaves me very uneasy.

The Dreamliner reminds me of the British Advanced Passenger Train, in which every single component was new, radical and unproven. The project ended up seriously behind schedule, massively over-budget, and was then pressed into trial service too soon. It was technically superb, but unreliable and a failure. For the time being this is one Boeing in which I am NOT going.

Lemain 14th July 2013 08:28

Hear Hear!
 
1a fast asleep:

Seems to me that everybody is very tight lipped about the source of the fire. By now a large number of people would have inspected the plane and it would be obvious where the fire originated, even if they cant ascertain why.

Boeing really need to quickly calm the world concern as a matter of protecting their reputation and the future of the 787.
Hear hear! I would only add that the entire aviation industry is harmed in such cases, especially now that there is essentially a global duopoly for the manufacture of advanced passenger jets.

Unfortunately, if you go through every speculation as to cause, in this thread, not one is likely to have a good outcome. A faulty coffee-maker? Yikes....that's arguably the most frightening of all.

WYOMINGPILOT 14th July 2013 08:45

"Quoting Mark Mangooni, Ethiopian Airlines' senior manager in Britain, the Financial Times reported that airline staff had discovered a problem with the aircraft's air conditioning system during a routine inspection and had seen sparks but no flames."

Now I really feel comfortable. The maintenance staff only saw sparks but no flames. The fire may have come from the air-conditioning ducting routed above the galley.

Stuffy 14th July 2013 10:27

Once the public get a negative mind set. It is difficult to recover a positive one.

What happens when the negativity is reinforced by another incident?

I am not convinced by the battery 'fix'. Putting it in a metal box with a venting tube if it should overheat again. Is not a solution.

It may have been the only solution ?

I am sure Boeing will get there in the end?

cockney steve 14th July 2013 10:39

To those who declare this hull to be a writeoff.

Like you, I'm not a Composites expert,however,I do have background knowledge.

Boats/ships have a long history of all-composite construction and remember the medium in which they're immersed ,is somewhat denser than air and a lot more turbulent -hence the vessel is a lot more highly stressed and suffers continual impact-stresses. (waves hitting! )

Manufacturers will always make more sections than they need....why?
Because some will be rejects, others will be required , complete, for repairs.
Rveryone seems to be fixated on "complete section" replacement....it's just not needed...in the case above ,of a reject, the faulty area can be hacked-out and the rest used to supply a part-panel.

There is no technical reason why a repair could not be pieced-in without loss of structural integrity.
The bigger problem, is the repair being TOO STRONG and transferring stresses to other areas not designed to absorb them!
(something that emerged in the development of motor-body crumple-zones.)
All this B/s about"holding up production" and " all sections already assigned to a build"....sheesh!

I wouldn't fly on one either, but it's got nothing to do with the structural integrity of "patched composites" FFS, that's how it's built in the first place!...."Airfix Kit " was nearer the mark than you realise ;)

Flyer94 14th July 2013 11:39

@ManaAdaSystem

Quote:
At least four times in my flying career I have had to "roll the trucks." Two of these times there was actual smoke in the cockpit (once closing down runway 18 in FRA much to the delight of the gents behind us...)

So Fritz did not shut down FRA, just one runway? THAT was a smart decision. LHR have shut down several times, even when one or both runways were available.



You know the layout of FRA? Closing rwy 18 for an incident at it's rear end does not necessarily require to close 25L/R. It's a very large distance between the end of rwy 18 and the traffic on 25 L/R. So if they didn't went out of emergency services it was easy to let open the airport.

blakmax 14th July 2013 12:02

Where do I start?
 
Geez, Cockney Steve

Where do I start? Firstly, remember the "Phillips Explorer", the multi-hull vessel that was designed to circumnavigate the world in 80 days and then had a "structural malfunction" in the English Channel just after Lizzie launched her, and then sank in the Atlantic on her maiden voyage? (Shades of the Titanic).

There are vast differences between structures restricted to water travel where weight is not as critical and margins of safety are far more generous and aircraft where margins are much more finely managed. In a marine environment, a bad repair may involve a desperate resort to a dinghy and activation of an EPERB but in aircraft a bad repair may have far more significant ramifications. You have no life raft and you can not swim for long in air.

As for the "air-fix" comment, it is difficult for most people to comprehend that almost every aircraft anywhere has some adhesive bonded structure and in my (extensive) experience in adhesive bond failure forensics there have been an inordinate number of adhesive bond failures to metallic structures, so casting aspersions towards a "plastic" or "bin-liner" structure shows a neanderthalic ignorance of structural materials. There are even more significant deficiencies in bonded metallic structures than there are associated with fibre composites.

Next the "too-strong" comment. In reality, the problem of load transfer is not strength related, it is stiffness related. A compliant-but-strong material (like fibre-glass, high strength but low elastic modulus) will not cause as much load interaction as a stiff-but-weak material such as mild steel (low strength but high elastic modulus). Stiffness causes load redistribution problems, not strength.

HDRW 14th July 2013 12:14

While I'm only a PPL, I do seem to know more about electrics than some posters on here, so I feel I should point out some items: Circuit Breakers and fuses that are away from the device being protected will only respond to an electrical overload - an overheating boiler, oven, whatever, would only have its circuit interrupted by a thermal device on the thing itself, not by an overcuttent breaker in a panel somewhere else. An overheating "heater" draws roughly the same current as one that's working normally, so nothing in the electrical system will "notice" the problem. Any heating device should have thermal overload protection, and if it turns out that something in the galley had been left on and resulted in this fire, then the thermal cutout must have malfunctioned. A friend of mine used to work in a domestic electrical appliance test laboratory, and they test thermal runaway to prove that the cutout will do the job, and also do "special" tests where the thermal cutout is disabled, to find out what happens then. (Anything from melting the element or the wiring to it, so disconnecting the circuit, to exploding and showing plastic everywhere!). I inadvertently tested my own automatic electric kettle recently, by leaving the lid open so the steam-sensor didn't work. Came back later to find damp wallpaper for the top three feet of the walls, and the kettle empty and turned off by its thermal trip. If a £15 kettle does this, £thousands of aircraft galley equipment will (should) too!

Airsafes 14th July 2013 12:17

Heat from lightning strikes - composite material
 
Whilst watching the news footage of the heat damage to the outer body on the 787 I wondered if anyone knows how lightning strikes are dissipated around the airframe on composite bodies compared to the older alloy airframes?
Plastic doesnt conduct but I would ahve thought the extreme voltage and heat would damage any plastic material?

I found some information on the wiki site about lightning strikes but wondered about its effects on composite material if anyone had any ideas?
Lightning - Wikipedia, the free encyclopedia
Some of its comments.
"As a result of their greater power, as well as lack of warning, positive lightning strikes are considerably more dangerous. At the present time, aircraft are not designed to withstand such strikes, since their existence was unknown at the time standards were set, and the dangers unappreciated until the destruction of a glider in 1999.[37] The standard in force at the time of the crash, Advisory Circular AC 20-53A, was replaced by Advisory Circular AC 20-53B in 2006,[38] however it is unclear whether adequate protection against positive lightning was incorporated.[39][40]Positive lightning is also now believed to have been responsible for the 1963 in-flight explosion and subsequent crash of Pan Am Flight 214, a Boeing 707.[41] Due to the dangers of lightning, aircraft operating in U.S. airspace have been required to have static discharge wicks to reduce the possibility of attracting a lightning strike, as well as to mitigate radio interference due to static buildup through friction with the air, but these measures may be insufficient for positive lightning.[42]"

jolihokistix 14th July 2013 13:00

Even the BBC today seems to be tiptoeing around this thing: "Fire-retardant foam was sprayed at the airliner and an area on top of the fuselage in front of the tail appeared to be scorched." :mad:

aergid 14th July 2013 13:10

Oh well may as well put my pennies worth in to mix also:

By looking at the limited quality of the photographs of the damage to this aircraft. a full section replacement will most probably be carried out.
As the Aircraft is manufactured as a complete section by section structure (not panelised) any permanent repair would obviously in my opinion have to the same.
Nobody is debating that this could or could not be an electrical fault causing the fire. If it is an electrical fault then the batteries are related as they are the primary electrical system. We will just have to wait see what the AAIB investigation throws up....

as for the Fire Service. If they had 2 incidents ongoing the OIC would close the Airport as he could not guarantee response times. Also as stated before once the larger tenders were emptied they would have to be topped up again before any decent CAT level could be restored. So bravo to the OIC for taking what would have been a very challenged decision but the I believe to the correct one:ok:

fenland787 14th July 2013 13:12


Even the BBC today seems to be tiptoeing around this thing: "Fire-retardant foam was sprayed at the airliner and an area on top of the fuselage in front of the tail appeared to be scorched." http://images.ibsrv.net/ibsrv/res/sr...s/censored.gif
Are they tiptoeing around or are they (unusually) doing what we often complain journalists don't do, ie not speculating and waiting 'till they have some facts?

SRMman 14th July 2013 13:21

Repairing the damage
 
Cockney Steve,
You appear to be knowledgeable on the subject, and also dismissive of comments made by others.
You read my post, and therefore will have seen that I suggested Boeing have TWO options; I further discussed the pros and cons of both. Whilst a patch repair may appear to be the best option, it is not necessarily straight forward, and requires a team of design, static and fatigue stress engineers to ensure all aspects (including attracting load) are covered.

I stand by all my previous comments, including what I said about Boeing being very unlikely to have available large fuselage sections to cater for repairs. Time will tell.

lomapaseo 14th July 2013 13:55

Can the ET 787 Be Patched Repaired
 
If not why not?

Bonding ?

Load Carry?

I'm interested in how the military handles this as well.

Of course I will be surprised if Boeing says it can't

With all the opinions on here maybe the technical answers should be moved to the Technical Questions forum

DWS 14th July 2013 14:55

RE # 280 AND LIGHTNING STRIKES
 
Its not an issue to be discussed here- and its not an issue PERIOD.
777 have been flying for over a decade with composite tail fin. US Navy planes like A6(E) have had composite wings for over a decade. Airbus has used a composite fin-rudder for nearly two decades. I'm sure all have been hit by lightning at least once in several decades.

techniques include built in ' screen' into layups, sealant caps on fastener penetration of fuel tank areas, plating of tank penetrations for larger parts,, etc etc etc.

Direct damage for strike area is minimal.

Spend UR time on the boeing site for example or on industy sites looking up the magic word ' lightning strikes damage repair etc .

LookingForAJob 14th July 2013 15:33


as for the Fire Service. If they had 2 incidents ongoing the OIC would close the Airport as he could not guarantee response times. Also as stated before once the larger tenders were emptied they would have to be topped up again before any decent CAT level could be restored. So bravo to the OIC for taking what would have been a very challenged decision but the I believe to the correct one
this one clearly isn't going away. I made some of this point very early on in this thread but the post got deleted - presumably because it was considered to be deviating from the main topic - but now I have a couple of minutes so I'll try again.

Here is how an airport fire service works in very general terms - what I'm describing is the case for the UK, but there are variations in other countries. An airport decides that it wants to offer itself to particular types and, importantly, sizes of aircraft. Depending upon the size of the largest aircraft that it wants to be able to accommodate, a certain level of fire fighting and rescue facilities are required. These are defined in ICAO Annex 14. Many airports that provide cover or higher categories - bigger - aircraft will actually exceed the minimum requirements for a variety of reasons.

Amongst the other requirements for an airport fire service is to be able to attend an incident anywhere on the airport within a certain period of time. It's important to note that this does not mean every fire vehicle and fireman has to get to the aircraft within that period. Usually what happens is that all the fire vehicles will head out to the incident when called, but a rapid intervention vehicle carrying a senior fire officer will quickly get to the incident and will assess whether some or all of the other vehicles on their way are required.

In the event of a serious incident the external fire services (and indeed hospitals, ambulances and so on) will also be called. In theory the airport fire service is there to provide immediate fire fighting and rescue service with particular expertise for the airport and aircraft environment. As soon as the external services arrive, they start to relieve the airport fire service who are then able to return to their base, replenish their media and in other ways prepare to provide the airport with its published level of fire cover again. During the turnout, as was the case at Heathrow recently, while an incident is being attended by the airport fire service, the level of fire cover available for other movements is reduced, perhaps to zero. In practice, it's likely that any aircraft on the approach or taking off will continue as normal but subsequent movements that require fire cover will quickly be advised of the situation and, we'll need to go somewhere else in accordance with their SOPs.

Those who were astonished, stunned, amazed, indignant and so on, at the picture posted earlier showing lots of fire engines surrounding the ETH aircraft, as was pointed out by another poster earlier, most of the fire vehicles look like they are from external services - as will no doubt be the case for the personnel 'twiddling their thumbs'. A quick glance suggests there are 6 external fire appliances and one or two senior police and fire service personnel cars along with one mobile incident control room (probably part of the airport fire service), two airport appliances, the airport fire boss's car and an airside ops vehicle. All standard fayre after a serious incident at a major airport.

By the way, note that not all aircraft require to have fire cover available. That will not be the case at Heathrow, but there are some situations where movements can continue without fire cover. Unless the runway is blocked, and even that is moot by some interpretations, the airport does not close - it merely cannot provide fire cover.

Return to the situation where the senior fire officer reaches an incident and determines that only a minimum level of response is required and that the majority of the vehicles can return to the station. There's no need to close the airport, it's just that the level of fire cover may be reduced temporarily. At Heathrow this week, it seems highly probable that with two incidents in progress either coincidently or in quick succession, fire cover was reduced to zero.

That the mainstream media cannot distinguish between this situation and the airport being closed may not be surprising. But some supposedly professional aviation people don't know the difference is worrying.

I mentioned early on that sometimes large airport the level of cover is greater than the minimum required in some circumstances. One example is to be able to maintain full, published level of cover for aircraft movements and still to be able to respond to minor incidents or to provide a limited level of cover the public buildings that tend to get put up at an airport. Another situation that is quite common is that of a large airport which requires more than one fire station in order to be able to provide the response required to meet the regulations. For anyone who is interested, there are situations, although not in the UK as far as I am aware, where an airport fire service may leave the airport to attend a fire in nearby areas because the external fire service is far distant - this arises for remote areas where the airport is providing, perhaps, the only access to the area.

This is the general situation. I, of course, would welcome clarification or correction from anyone intimately aware of the current procedures at Heathrow.

Momoe 14th July 2013 16:36

Fire cover is determined by strict parameters, if those parameters can't be met then there is insufficient fire cover.
In the event of insufficient fire cover, it appears that LHR is not open for business, for low fuel state aircraft LTN/STN/SEN and LGW are viable alternatives with minimal additional flight time.

We don't know who calls the shots, whether it's the chief fire officer or higher up, triggered by the insufficient fire cover call from the fire services?

Statistically, the chances of an accident are slim if it remains open, but ATC sorted it out and re-directed aircraft to airports with fire cover without too much drama, maybe those operatives who dispatch without alternatives should rethink their policies rather than Heathrow?

Passenger 389 14th July 2013 17:27

Multiple posters have complained (or expressed bewilderment) that Boeing did not quickly issue a statement regarding the cause of the fire.

One factor may be that Boeing is a publicly traded company. My understanding of United States securities laws is rusty, but my recollection is that publicly traded companies can be sued for making statements that later are alleged to have been false or misleading and thereby impacted the stock market. A small army of American lawyers grew very wealthy by filing many such claims, whether meritorious or not (the cost of defending the claim can be so great that a company pays just to stop the bleeding).

The law governing such claims has changed considerably in recent years, and is now less favorable to claimaints (and their lawyers), yet it surely remains a consideration.

No doubt Boeing's lawyers are carefully reviewing any prospective public statement with that in mind (along with other potential legal issues).

phil gollin 14th July 2013 19:46

Just to note that considering the large number of CCTV cameras which almost certainly covered the incident it is quite amazing that no video footage has surfaced of the discovery and initial fire response.

It would seem that Fleet Street HAS cleaned up its act.


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