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Ethiopean 787 fire at Heathrow

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Ethiopean 787 fire at Heathrow

Old 14th Jul 2013, 22:19
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LHR Fire cover

I've seen fire cover requirements refering to ICAO Annex 14 mentioned here.
The actual place to go is Chapter 9.
There you will find the level of fire cover required based on size of aircraft.
This is where Heathrows problem is somewhat obvious.
The amount of water/foam necessary to be available for Cat 6 and above aircraft, which most of LHR's movements are these days (i.e. Widebody's) is about 9 times the requirement for Cat 4/5 typically smaller 737/A319.
So, LHR probably could have stayed open for the smaller aircraft and remained legal for CAA purposes but couldn't meet the higher level required by most of its movements. I can see the headlines now "Newcastle A319 allowed to land while Beiging flight forced to divert", probably easier on ATC to divert everyone than pick and mix.
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Old 14th Jul 2013, 22:37
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Can't believe how anxious people are to rubbish the B787 and how short their memories are!

I remember some years ago arriving at CDG one morning to see a very new A340 sitting in a maintenance bay almost completely burnt out, didn't generate a fraction of the hysteria that the Ethiopian B787 is managing.
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Old 14th Jul 2013, 22:47
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If it is an electrical fault then the batteries are related as they are the primary electrical system.
Eh? Primary?
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Old 14th Jul 2013, 23:27
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The requirements are set out in CAP168 chapter 8, not 9, chapt 9 is emergency planning.

If the RFFS cat is declared as 0 it means that, yes the cat could be lowered if appliances, media and personnel are available to respond.

Last edited by Nubian Major; 14th Jul 2013 at 23:28.
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Old 14th Jul 2013, 23:46
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"The requirements are set out in CAP168 chapter 8, not 9, chapt 9 is emergency planning."

Agree, the UK interpreted requirements of Annex 14 Chap 9 are in CAP168 Chap 8.
But the whole point is the high level of fire cover required for the type of aircraft operating through LHR in general today.
If they empty one of those big tenders on a small fire that puts the level of fire cover down until it's replenished.
We might all say why haven't they got more tenders, there lies a cost benefit v frequency of incidents arguement.
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Old 15th Jul 2013, 00:33
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@newvisitor:

Thanks for your thoughtful post. I also have read with interest the posts from amicus, who is so obviously worried about the inflammibility of the epoxy resin in the composites make up the skin of the 787 fuselage, and who reports that he was on the losing side in a battle to get the upper part of the fuselage skin lined with thermal insulation.

I also read with interest from the FAA report on flammability properties of these materials that, "Typically, surface combustion needs a high temperature to be sustained, which is usually in excess of 500°C."

In isolation, that the material can burn is an interesting fact suggesting obvious concerns. But it seems to me that more must be taken into account in order to understand the implications of this fact for safety of air transport flights as dynamic systems.

I take as a premise that a powerful fire onboard a pressurized transport at altitude is an extremely dangerous event (whichever materials are used in the airframe), and generally non-survivable unless the fire's duration is limited by fire suppression or exhaustion of fuel/oxidizer.

Though I claim no expertise, I have worked as an engineer in the fire protection industry -- I wonder whether a fire capable of heating a significant area of composite cabin skin to 500+ Celsius for more than a few seconds wouldn't be quite a nasty blaze in its own right. I haven't done any of the analysis necessary to quantify this, which would have to take into account such factors as cooling by conduction to the outer surface.

Wondering about the safety issues of composite skins, brings several questions to mind:

1. Considering the kinds of fires that have been observed or are relatively likely in air transport cabins, how large and sustained would such fires need to be, in order to create the conditions required for sustained burning of the composite skin? For the purpose of discussion, I'll coin the name composite burn-up fires, or CBU fires for short, to refer to cabin fires sufficiently energetic to cause such skin burning.

2. How would conventional aluminium aircraft skins perform under the conditions of CBU fires as defined above?

3. Subtracting the combustion products from the composite skin itself, would the cabin air be able to sustain life in fires meeting the CBU criterion? What would the survivability implications be, regardless of airframe materials?

4. How much toxicity would combustion of the composite resins add to the cabin air, as compared to the toxicity from the CBU fire conditions that would precipitate skin burning?

I get that amicus objects strenuously to the 787's present application of these materials. My questions are about the practical safety implications of this technical vulnerability. In real-world fire scenarios (sadly, smoke/fire incidents on airliners are not so uncommon), what kind of differences in outcomes might be expected, taking the related factors into account?

In a way, we may be thankful for the incident in London, in which noone was hurt. Fire experts will be able to provide some estimates of the power and duration of the fire, offering a practical case of "how bad it got" in order to burn through the skin. Hopefully, the investigation will also address temperatures and toxicity of the cabin atmosphere during the blaze.

I also hope that some assessment can be made of the extent to which the aerostructures were compromised by the damage, and what the structural implications might have been for the plane's ability to land, had such damage occurred in flight.
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Old 15th Jul 2013, 01:48
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The reason that the A340 fire in Paris did not cause the same hysteria is that the cause was quickly identified i.e. the yellow hydraulic electric pump failing to stop after the cargo doors were closed and overheating. Quite different from the B787 problem where the cause still has not been found.
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Old 15th Jul 2013, 02:21
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Quite different
from the B787 problem where the cause still has not been found.


So you think the hysteria will die down when the cause of the Ethiopian fire is announced? It has certainly been found but disclosure will be in the hands of the Boeing legal team who will almost certainly have sub-contractor and product liability considerations and don't wish to set themselves up for being sued.

There is a very unhealthy anti Boeing cult developing, nothing short of cancellation of the B787 will satisfy them.

Last edited by parabellum; 15th Jul 2013 at 02:27.
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Old 15th Jul 2013, 03:39
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I wouldn't agree entirely on the whole 'anti Boeing' line of thought,but i can understand your point.
I just think people really do want to makes sure or understand that crew/pax will be safe when flying on these aircraft.I personally would like to think that the Boeing engineers had already thought these problems through with regard to fuselage integrity and the survivability of the aircraft to remain intact and airworthy if a fire took place in flight. Not forgetting the pax/crew being able to survive on the rubber jungle and bottles.
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Old 15th Jul 2013, 04:09
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I personally would like to think that the Boeing engineers had already thought these problems through with regard to fuselage integrity and the survivability of the aircraft to remain intact and airworthy if a fire took place in flight
As an retired Boeing Engineer I would like to agree with you, but sadly, few such engineers/techs had much to say about such design issues. In the name of cost savings, reduced research, and bucu outsourcing, the majority of those type of decisions were tempered by the faster- cheaper method. Thus we had the fubar non testing of batteries ( driving a nail thru one cell for example ), few system tests of an all up system, etc. NOT that those in charge deliberately looked the other way, but instead the working grunts either bailed out when able, or put self survivablity above pressing an unpopular with top brass questions or issues. Power point rangers rule the roost- thus we had the PR team insist on rollout of an empty shell just to make a nice pr date of 7-8-7.

Consider that the 747 was designed, built, flew, and a new factory was built in less time than the delays on the 787.
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Old 15th Jul 2013, 04:38
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NewVisitor,
.Thank you for your thoughtful and rational comments, they are much appreciated.
I have been working in aerospace engineering since being a young squirt apprenticeship in 1952 at De Havillands. We even had a composites departmen in 1952, well only the superb Mr. Johnston, who I served under for six months and learned copious initial composites knowledge and data from that kind and superb gentleman.
In the early 50's,we employed Redux phenolic bonding extensively on our aircraft including the Sea Vixen and the ill fated Comet 1 for stinger to wing skin bonding as well as for many fuselage components.
I have been working and specializing in the design and analysis of aerospace composites since the mid-60's, so I hope that I know enough to contribute something of merit, from both the engineering and historical aspects of composites in in paricular, the flammability and fire hazards of the 787.
Incidentally, I finished my engineering career consulting concerning composites for three years at Boeing Commercial, so I know pretty well Boeing engineering and BMT. plus Allen Fawcett pretty well as well as many others composites folks at Boeing or now retired.
My point in writing extensively concerning both the flammability and FST hazards of the epoxies on 787 stems from a lot of experience working on FST with NASA, Moffet, Ciba-Geigy, Celanese and several other companies in the early 70's. I I worked for many years getting all FST hazardous epoxies banned for A/C interiors for many years or even decades and the FAA finally passed the no epoxy for interiors in the middle 80's.
Now we are faced with epoxies with FST hazards all over the 787 and the flammability and FST problems inherent therein
I have had many discussions since 2005 with FAA , Boeing, Airbus et al concerning the FST hazard inherent in that A/C,and , I note, trying to work properly through the FAA system. Clearly and undeniably there exists both a flammability and major FST hazard on that A/C calling into question survivable crash flammability and crash hazards.
In summary, I got nowhere, as the FAA always ignored my comments or paid stand bureaucratic lip service with no resulting safety corrections, crash testing or the like, so now we are unfortunately placed as engineers and , I hope,well qualified composites experts, fearing a fatal incident on 787, which could have been and should have been avoided.
Concerning the Ethiopian fire, I again note that the FAA agreed, under strong Boeing pressure, to only have internal burn-through fire insulation on the lower half of the 787.
I protested long and loudly to the FAA concerning the lack of any such insulation on the upper 180 degrees of the fuselage and the LHR fire was in the right place to prove my point, their errors and fortunately with no loss of life, THIS TIME.
I lived through and worked upon the Comet disasters and don't want that experience repeated, but it will be if strong steps and measures are finally and rapidly taken by Boeing, the FAA, EASA and NTSB to correct and remedy the inherent design deficiencies of the 787.
I am neither a Cassandra nor an eccentric, merely a aerospace engineer specializing in design and analysis of composites engineering since the early 60's plus Mr. Johnston's earlier wisdom and training in composites and biffing me around the ears in the early 50's at De Havillands.
And you, Sir, are a breath of sanity and fresh air on this forum as there has been much codswallop written here regarding fires, repairs, and crash-worthiness et al on this board and my Boeing engineering and BMT friends grew to be well attuned to that remark and assessment and remarks concerning codswallop in my three years consulting with them.

Last edited by amicus; 15th Jul 2013 at 04:51.
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Old 15th Jul 2013, 05:12
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Amicus and Newvisitor

Hats off to both of you. Your rational exchange is what PPrune used to be. Your experience and knowledge, articulately stated, brings the conversation back to an intelligent exchange of ideas and allows the rest of us, without your specific skill set, to listen and learn.
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Old 15th Jul 2013, 05:21
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787 Certification - Fuselage - Special Conditions

Amicus...and others. I read your comments with interest.
Interesting to consider the Heathrow fire in the context of the 787 Certification and its Special Conditions for the fuselage. To what extent did the 787 Certification Special Conditions address flammability and survivability then - or was that ('Composite Fuselage ' Special Condition) related only to the physical fuselage structure and its capacity to withstand physical forces in a crash landing.
In the past I have tried to get more detailed information on what the 787 Special Conditions actually mean in practice - especially the ones relating to lithium ion batteries and the fuselage crashworthiness - but without success.
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Old 15th Jul 2013, 05:34
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Uncle Fred,
My sincere appreciation and I can only hope that pprune restores itself to its old glory and get rid of the ongoing and wasteful dross and codswallop, so evident of late and in this current thread. I am most grateful yourself and to New Visitor for giving me hope of correction and change.

Thank you, again, Sir,

Last edited by amicus; 15th Jul 2013 at 05:36.
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Old 15th Jul 2013, 06:21
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it's not going to be as easy as hitting the TOGA button and taking the shortest route to that nice nearby airport and landing there. All of the normal flows of traffic will be disrupted.
Ultimately it comes down to "Command" and awareness.

Any airfield, be it 1, 2 or 3+ RWs could "close" with no notice. Fuel policies allow (but do not require) you to re-arrange your flight to land with "(just) above Reserve" without telling anybody (e.g. ATC) nor having a "Plan B" (Diversion).

I have my "ways" of dealing with such situations, I am sure others have theirs. They vary from informing ATC as soon as possible if a GA will result in either a PAN or Mayday. I suspect (but do not know) that if an aircraft was inside 5NM for LHR, and had clealy notified LHR that "in the event of a GA I will be declaring a Mayday for Fuel", then on Friday they would have been allowed to land.

In the event a short of fuel late GA happens, I will have briefed with my colleague the "bottom" line. This might be 7700 and direct track to 8NM final at XXX, whatever ATC say.

Others may, or may not, disagree. But the other side of the coin - working without thought to minimum fuel policies, and then expecting the normal ATC system to cope with mass diverts and have everybody on the ground with > Reserve, I think is "optimistic"
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Old 15th Jul 2013, 06:29
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I have found the discussions on composites extremely interesting. As a lawyer I am currently involved in litigation surrounding the blast effects on laminates so the whole debate is fascinating.
However, as illuminating as the discussion may be, I would avoid flying in a 787 until everyone was satisfied that the aircraft is safe. As things stand, there is a great deal of evidence that suggests the 787 needs more time to work through its teething problems - without passengers on board!
Heaven help Boeing if there was a major accident as a result of some fault - batteries or otherwise.
To use an old adage, they are "playing with fire".
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Old 15th Jul 2013, 07:31
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I don't think threre's anything particularly anti-Boeing about this.

When ETOPS first came about, the industry set about demonstrating how 2 engined aeroplanes could reliably operate across the wilderness without compromise.

We now have a new aeroplane type that appears to have a predisposition to fire to such an extent that the aircraft could be quickly compromised.

Given its intended market, I believe that is genuine cause for concern.
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Old 15th Jul 2013, 07:57
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Amicus and Newvisitor

Hats off to both of you. Your rational exchange is what PPrune used to be. Your experience and knowledge, articulately stated, brings the conversation back to an intelligent exchange of ideas and allows the rest of us, without your specific skill set, to listen and learn.
You may recall I quizzed amicus early on about the clear knowledge of the 787 and materials

That has led to rather a lot of reading over the weekend of websites / articles, some of which I suspect are authored by amicus. They are not whacky theories, but asking Boeing/FAA probing questions and seemingly not getting the answers.

The articles seem to pre-date the A350 final design, which has now also gone down the composite route, at times apparently against some at Airbus' judgement who might have preferred the A380 "hybrid" route?

As such, I feel better informed and will follow the ET follow up with interest - and maybe cross referred to the 777 SFO accident.

What I am still unclear about is how "different" the A350 is to the 787? 1 difference is "panel" fuselage construction (A350) v Barrel (787) - the panel being simpler and easier to repair i.e. in the ET case, it might require the whole aft fuselage "barrel" replaced if it cannot be patched.

The burn / insulation differences between the 787 Toray 3900-2 and A350 Hexcal M21E materials / construction would also be of interest if anybody can help...


PS if anybody is interest please see Lonely Scientist and the 'Impossible Dream' chapters...
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Old 15th Jul 2013, 10:25
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Amicus was vocal on the issue in 2011 when LOT had the unfortunate wheels up landing.

See http://www.pprune.org/rumours-news/4...ml#post6784032

Edited to say: Amicus was vocal as far back as 2007...!! Search for his enlightening posts ...

Last edited by Desert Dawg; 15th Jul 2013 at 10:29.
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Old 15th Jul 2013, 14:08
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A quick question - what UK agency does the official investigation on an event such as this?

The Toulouse A340 runup accident was classified as an industrial accident, not an aviation accident, and thus BEA did not do the final report. Similarly, in the US, it would probably be OSHA and not NTSB doing the official investigation.
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