back to article UK investigators finger emergency beacon for 787 Heathrow fire

The initial accident report into the Boeing 787 that caught fire at London's Heathrow airport last week has concluded that the fault likely lies with the aircraft's emergency location beacon, and it recommends disconnecting it as an interim measure. The world's third-busiest airport was shut down for over an hour on Friday …

COMMENTS

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  1. Dick Pountain

    Won't be told

    Said it before - lithium batteries are too cranky for aeroplanes (especially plastic aeroplanes). Burning a hole in your trousers is unpleasant, burning a hole in an aeroplane is a disaster.

    1. Falanx
      Mushroom

      Re: Won't be told

      Please RTFR, lithium manganese dioxide batteries are worlds away from lithium ion and lithium polymer batteries...

      1. Anonymous Coward
        Anonymous Coward

        Re: Won't be told

        Correct, we use lithium batteries down oil wells, where it is notoriously hot and unpleasant. They don't just explode for no reason.

        We have a lot of problems with this airplane because of the wiring.

        Wiring is a bugger like that. You can spend all day designing the best widget in the world, but get the wiring wrong and it's screwed anyway. You have no idea how many electronics issues can be traced back to it.

        1. itzman

          Re: Won't be told

          have you any idea how hot an aircraft skin, parked in full sun, gets...a LOT hotter than down a mine or well.

          Especially if its made of carbon fibre..

          1. Anonymous Coward
            Anonymous Coward

            Re: Won't be told

            Then something needs to be done. Although carbon fibres can take pretty high temperatures, the polymers that hold them together cannot.

            The reason that glass fibre boats are painted white is because otherwise in the tropics the hulls could overheat and delaminate. Polyester, vinylester and most epoxies are not really Lloyds certifiable because they are not boilproof, whereas things made of resorcinol glued wood are.

            I doubt that the skin gets hotter than it can get down an oilwell. But I'm prepared for someone to tell me I'm wrong, and cite numbers.

      2. itzman

        Re: Won't be told

        No they are fairly similar.

        Better, but still liable to burst into flames at elevated temperatures. And still able to easily destroy themselves and start a fire when shorted.

    2. LarsG
      Meh

      Lets hope

      That when one crashes a survivor will be able to use his mobile phone to call the emergency services!

      1. Anonymous Coward
        Anonymous Coward

        Re: Lets hope

        So long as they don't rely on Apple Maps for their location that is.

    3. itzman

      Re: Won't be told

      I think that is overly harsh.

      Lithium batteries can be used, but the cooling requirements of a carbon fibre aircraft are making a bit of a difference.

      The old 'well its always worked before' approach is not it seems working now.

      It will get solved, BUT not before Boeing has taken a big commercial hit.

  2. Daniel B.
    Facepalm

    Wait

    ... they're disabling an emergency beacon? Really?

    Given its function, it seems to be the kind of stuff you really want to have if the airplane ever crashes! Wouldn't it be better to fit a non-flamey version of the beacon instead of leaving the airplane beaconless?!?!

    1. Rob Carriere

      Re: Wait

      Certainly, but they might not have a non-flamey version lying on the shelf. Different device, likely different shape and so on. So that's the solution you want to work towards, but not an immediate one.

      Until then the question becomes, which is the greater risk: the aircraft crashing and rescue being hindered by absence of an ELT, or the aircraft catching fire by the presence of one. Note that on-board fire-fighting kit proved insufficient to the task -- you really don't want this happening in flight. Give the rarity of crashes, reducing the risk of fire is almost certainly the smarter choice.

      1. Allan George Dyer
        Boffin

        "likely different shape and so on"

        But that's what Duct Tape is for.

        1. Tom 13
          Joke

          Re: that's what Duct Tape is for.

          Just make sure to use the roll that comes with round things. The ones that tear off in rectangular brackets will suffer too much stress.

        2. Anonymous Coward
          Anonymous Coward

          Re: "likely different shape and so on"

          It's Duck Tape. No, really. It may get used for taping ducts, but the original inventor still sells it as Duck Tape.

          1. John 62

            Re: "likely different shape and so on"

            The dutch word 'doek' is the origin here and when used with tape it refers to adhesive tape made from or strengthened by cloth. Hence duck tape and Duck (R) tape. Some jurisdictions don't allow it to be used on ducts unless it is specially treated.

            http://en.wikipedia.org/wiki/Cotton_duck

    2. Crazy Operations Guy

      Re: Wait

      The aircraft still has emergency beacons, the ELT is just more accurate than the others. A typical passenger aircraft will have 3 small beacons: 1 in the nose section, another right between the wings, just under the deck plating and one in the tail assembly, some of the bigger planes have more or attached as optional components depending on purpose of the craft.

    3. Voland's right hand Silver badge
      Devil

      Re: Wait

      I do not see a problem with it - provided that its FAA certification is adjusted accordingly. I do not see how on earth, in hell or otherwise an aircraft which does not have a functioning beacon can have 270 minutes divert allowance (that certification without an operating record was insane in the first place). With a non-functioning beacon it should not be allowed the normal 60 which nearly all two engine aircraft have as it is.

  3. Anomalous Cowshed

    Boeing was minding his business...

    Farmer Boeing was riding on his ass, making his way slowly towards the village market, ogling the buxom farm girls in their colourful dresses, when a strange, unsettling and brittle worm-like creature appeared out of the blue and bit him for no apparent reason.

  4. Mage Silver badge
    Alert

    Plastic Vs Aluminium

    Surely ANY fire or risk of fire is worse in this plane than the older ones. Surely it needs higher standard wiring and LOWER fire risk design parts.

    Was too much outsourced and cost reduced?

    How do you make brittle Teflon (PTFE). That's an achievement.

    Also other than Glass or Ceramic or Fibre glass about the most fire proof cable insulation*. Used since WWII for expensive wiring.

    *You can burn it, but it needs a lot more heat than say PVC.

    1. Anonymous Coward
      Anonymous Coward

      Re: Plastic Vs Aluminium

      I see you've got a downvote already. Some explanation from the downvoter would be welcome.

      Is it my imagination or do I remember PTFE wirewrap (and other) wire in the 1980s? IE It's not exactly new (WW II even before that!), and you would hope that by now its characteristics should be widely understood. I

      Whereas the characteristics of composite fuselages, in the unseasonal London sun for 8 hours with no electricity to power the aircon, therefore getting hotter by the hour in the higher parts of the fuselage (heat rises, etc).. no, surely nothing that simple... surely please?

      "Was too much outsourced and cost reduced?"

      Maybe the downvote means somebody doesn't want that question asked or answered? Some of us already have our opinions.

      1. SkippyBing

        in the unseasonal London sun for 8 hours

        Whereas in Ethiopian Airlines home country it's never exposed to those kind of temperatures...

        1. Anonymous Coward
          Anonymous Coward

          Re: in the unseasonal London sun for 8 hours

          "Whereas in Ethiopian Airlines home country it's never exposed to those kind of temperatures..."

          Stop and think for a moment. Just a moment.

          Any of the experts reading here know what Standard Operating Practice for ground power is in sunnier climes than LHR?

          Maybe routinely leave the aircraft with ground power active, maybe to run a bit of ventilation, maybe even run a bit of cooling? Would seem sensible to me, although Skippy doesn't seem to think so.

          In the LHR incident the ground power was switched off, the aircraft was shut down, including the ventilation and aircon. In the hot sun, unventilated aircraft get hotter by the hour till they reach equilibrium, just like unventilated cars and vans, except bigger and hotter.

          In an aluminium skinned aircraft you've got decent thermal conductivity. Significant hotspots aren't that likely.

          Who knows about the thermal conductivity of the Plastic Padding used on this aircraft, or about SOP in sunnier climes?

      2. Intractable Potsherd

        Re: Plastic Vs Aluminium

        "Whereas the characteristics of composite fuselages, in the unseasonal London sun for 8 hours with no electricity to power the aircon, therefore getting hotter by the hour in the higher parts of the fuselage (heat rises, etc)"

        And according to a poster at PPRuNE (Professional Pilots' Rumour Network) who seems to know his stuff, there is inadequate (read "no") fire-retardant material in the top half of the fuselage on the 787 (see postings by amicus at http://www.pprune.org/rumours-news/518971-ethiopean-787-fire-heathrow-20.html). He also writes that the resin used will ignite at about 550 degrees F (288deg C), and that it is the same stuff that got banned for use on oil-rigs after Piper Alpha. Just to add to the fun, he reckons that a fire that burns through the skin whilst in flight will tend to propagate in the air-flow rather than extinguish (like a blown-on cigarette end, as I imagine it). Now, I don't have the technical expertise in composites to evaluate all this, but it makes me rather worried about this particular aircraft if even part of it is true! Now add a new type of wiring that is brittle, and I think I'll be avoiding it for a considerable time.

        1. Anonymous Coward
          Anonymous Coward

          Re: Plastic Vs Aluminium

          If you think Wikipedia is a poor primary source, until you've seen PPRunNE you ain't seen nothing, son.

          Not too long ago, one contributor wrote in regard to a fairly minor light plane incident that "He could not rule out alien involvement" and he was absolutely dead serious.

          1. Anonymous Coward
            Anonymous Coward

            Re: Plastic Vs Aluminium

            Wikipedia and PPrune are both mixed bags. Some rubbish (aliens, and for this incident the "no reason to close LHR completely" meme), and some sources of definitive information (links to legit Boeing and other documents about what's where on this aircraft) and some sources for further research which outsiders may not otherwise have known about (e.g. Piper Alpha should hopefully be well researched and documented, though how much of it is readily available on t'Interweb is moot given that we're talking late 1980s).

            PPrune has now caught on to the "parked in a sunny place" discussion but as yet no one's asked whether the standard operating procedure in sunny places includes forced ventilation/cooling, and whether ground power (which was off at LHR) is needed for forced ventilation/cooling.

            Much of amicus's stuff is detailed technical stuff in his own particular field, which most of us won't be able to comment on let alone benefit from.

            One very valid point he makes should be understandable by most folk here [paraphrased]:

            "In an aircraft with a relatively short history (less than two years of flying and not many total hours in the air), there have already been three fuselage fires. What should that be telling us?" [paraphrase ends]

            Isn't that a fair question?

            Does anyone at Boeing HQ remember the Ford Pinto fuel tank story, or isn't that story fashionable on MBA courses?

            1. Anonymous Coward
              Anonymous Coward

              Re: Plastic Vs Aluminium

              Even mentioning Ford in the same sentence as Boeing is an insult to Boeing engineers. And I say that as someone who hopes Airbus crushes Boeing's nuts (big local employer).

              But you are right about one thing. Like the Library in the Borges story, Wikipedia contains both truth and falsehood. As a result, it's impossible to use it except as a lookup for subjects you actually already know about, which rather defeats the purpose.

          2. Yet Another Anonymous coward Silver badge

            Re: He could not rule out alien involvement

            To be fair - he couldn't

            I think this is going to be my new favourite phrase for bug reports

      3. Anonymous Coward
        Anonymous Coward

        Re: Plastic Vs Aluminium

        We used PTFE clad wire in the late 1970s. It was for tropicalised equipment being sent to India, where the cockroaches eat PVC. (I am not making this up).

        I find it hard to believe that it could get brittle so quickly; it had a lot more elongation than PVC. The insulation only needs to be quite thin and so the wire is very light, but the weight saving on a two tonne machine tool really was not significant. It cost a lot more, though. I remember being phoned up by the foreman at BICC to ask whether we wanted the marking on the earth wire straight or twisted, because he hadn't got the original order and if they made the wrong one there was virtually no chance of selling it to anyone else.

        I could be persuaded to believe that the thin insulation makes it more prone to wear through due to vibration.

        Also, unpleasant as the fumes from hot PVC may be, the fumes from overheated PTFE are much, much worse. Fluorine is one of the nastiest substances out, up there with mercury. You may survive inhaling hydrogen chloride, but fluorine gas is more or less guaranteed death.

        1. Yet Another Anonymous coward Silver badge

          Re: Plastic Vs Aluminium

          Insulation - we don't need no insulation. This is an American aircraft, post-and-wire was good enough for our houses it should be good enough for airplanes (*)

          (note: come the counter-revolution this word will be banned)

    2. RegGuy1 Silver badge
      Joke

      How do you make brittle Teflon (PTFE). That's an achievement.

      That'll never stick.

    3. Snake Silver badge
      Alert

      Re: Plastic Vs Aluminium

      PLEASE someone tell me this whole wiring story is not true. :-(

      For all the self-professed techies around here, I guess it is apparent that most have no interest in aviation technology. Brittle wire? To learn what it can do Google "Kapton", and then "Kapton Swiss Air", and learn the horrors.

      Yes, you can indeed make" brittle" PTFE coatings - the PTFE is combined with other ingredients in hopes to gain additional advantages. PTFE might be flexible in native state but it has other problems - it does not have the utmost in abrasion resistance and, even worse (from an aviation perspective) according to Wiki's tech article, it degrades over time with exposure to temperatures over 79 C / 117 F. If you think that those temperatures are never reached in an aircraft, I would advise you to study NTSB's TWA Flight 800 technical briefing at http://www.ntsb.gov/doclib/reports/2000/AAR0003.pdf and hit section 1.16.5.1 starting at page 124 / PDF page 142 :o

      Anyway, the EXACT quotation from the source material story regarding the Teflon wiring is:

      "To my amazement, I have been told by someone in the know, that the Teflon insulated wire being used on the Dreamliner is so fragile (emphasis mine), mechanics are prone to saying, "Don't look at it too hard or you'll break it." Teflon insulated wiring helped save weight for an airplane Boeing billed as 20% more fuel efficient."

      This may be the EXACT the same failing of Kapton - in this case, the PTFE insulation may have been made so thin, in the name of weight savings, that it simply cannot stand up to the physical abrasion / heat-cool cycles that an airliner places on it. The suspected cause of Swissair 111 was Kapton abrasion and this lack of abrasion resistance was what led to Kapton being BANNED by the U.S. Navy and the FAA ended up issuing numerous AD's (Airworthiness Directives, the highest level of 'recall' notice) to cover it. Millions of dollars were spent after Swissair 111 in rewiring aircraft to get rid of Kapton in various systems due to lack of durability and if they have created the same situation in the new PTFE wiring, in the name of weight savings, we are in for serious trouble.

      1. Falanx
        Mushroom

        Re: Plastic Vs Aluminium

        And making additions to that extruded PTFE would be for what reason? As an actual *materials* engineer, not the idiot mechanical engineers we spend all day fixing the screwups of and who are responsible for this 'PTFE is too brittle' nonsense, PTFE extruded insulation is used because of its fireretardence and excellent environmental and electrical performance. PTFE does exist as a *bulk* engineering polymer with lots of different additions, but no-one on earth is going to try to extrude Glacier DU around a gorram piece of nickel-plated copper wire. The reference in WIki is bunk. PTFE has a continuous upper working temperature of about 150 degrees. That's continuous as in, forever.

        And, really? Brininging kapton into the conversation to muddy the waters? Kapton is polyimide, a thermosetting polymer not a thermoplastic, with entirely different set of chemical mechanical and environmental properties for PTFE. This is nothing like the issues with kapton insulation, thank you very much.

        *Seethes at the general ignorance*

        1. Crisp
          Pint

          Re: Dammit Falanx!

          You made me learn something!

          On a Friday as well!

        2. itzman

          Re: Plastic Vs Aluminium

          Yerrs, what you say is true BUT we have a situation in which a battery has exploded and an aircraft has caught fire. Iether te barrety did that all by itself because it was flaming hot, in which case its either something about the CF that is causing hugely elevated temps, or ots something about the wiring.

          As far as parking aircraft in Ethiopia, the dreamliner hasn't been parked in Ethiopia yet.

          That beacon goes into dozens of other aircraft. They don't routinely catch fire. Ergo there is something specific about the aircraft installation.

          One of the things in that aircraft, is that its using low weight wiring. Its too soon to say, but that is at least a likley candidate for further investigation. As is temperature monitoring of a parked aircraft to see just how hot it really is getting.

          I would not be surprised to see temperatures approaching 180C at or near the CF surface. It is a great absorber of sunlight., And a coat of white paint is not as good as being a reflective metallic surface.

          These are all soluble issues, but until they are solved, its not looking good for this plane.

          1. This post has been deleted by its author

          2. Anonymous Coward
            Anonymous Coward

            Re: Plastic Vs Aluminium

            "That beacon .. don't routinely catch fire." : Yes, something is very likely different here.

            "the dreamliner hasn't been parked in Ethiopia yet" : I didn't know that, and probably most other readers didn't either. Including SkippyBing, apparently.

            "temperature monitoring of a parked aircraft to see just how hot it really is getting." :Surely they've already done this? Please?

            The bit that particularly bothers me is the combination of large quantities of niche materials, in relatively new applications, combined with old operating practices, e.g. if you KNOW it's going to be hot, maybe you leave the ventilation on, but London isn't hot, therefore switching ground power off is OK. After all, that works for all other aircraft in London in the past doesn't it, and nothing's new and untested here is it?

            " low weight wiring .. likley candidate for further investigation" : Yes. Afaict the only wiring from the ELT to the airframe is low power wiring, for something like a "test" button in the cockpit. Not power wiring. We'll see.

            "These are all soluble issues, but until they are solved, its not looking good for this plane." : Not good also for the people who have approved it for commercial flight, seemingly on the basis of little more than all the suppliers promising that everything would be OK (an exaggeration perhaps, but how much?).

            We wait and see.

            1. SkippyBing

              Re: Plastic Vs Aluminium

              Apparently I should be more explicit when I make my points.

              Is a slightly warm London the warmest conditions a 787 will have been parked in? I doubt it, ANA uses them and last time I was there Tokyo was pretty warm as well. Shockingly airline manufacturers heat and cold soak their aircraft as part of the design and certification process.

              Will there be procedures for parking in warm weather? Probably if it's thought it could be an issue, if not it's likely adverse reactions would have occurred somewhere else first as a seasonally warm London is quite mild compared to a lot of places.

              Will these procedures list the airport they should be carried out at? I doubt it, they'd probably use something more reliable like the air temperature. If only there was some way of getting that at an airport...

              1. Anonymous Coward
                Anonymous Coward

                Re: Plastic Vs Aluminium

                Forget the PTFE, the really worrying bit is "the French company Labinal, which specializes in electrical wiring used in the 787".

                French electrics? In an airplane? They've never heard of Renault?

          3. Anonymous Coward
            Anonymous Coward

            @ itzman

            "As far as parking aircraft in Ethiopia, the dreamliner hasn't been parked in Ethiopia yet."

            Where did that come from ?

            AAIB - landed at LHR...... after an uneventful flight from Addis Ababa

        3. Anonymous Coward
          Anonymous Coward

          Re: Plastic Vs Aluminium

          Upvoted for supplying information in a digestible format. I join you in your seethe. Anyone who doesn't know the difference between kapton and ptfe really shouldn't be posting on this forum, especially if they actually have responsibility for any wiring in difficult conditions.

    4. Anonymous Coward
      Anonymous Coward

      Re: Plastic Vs Aluminium

      The dreamliner is trying to be more fuel efficient, hence weight reductions. But this is moving into uncharted territory as a result.

    5. DanceMan
      Boffin

      Re: Plastic Vs Aluminium

      Theatrical lights use what I believe to be teflon wire to the sockets, where it gets quite hot. The jacket on this wire is tough. It's been in use in the theatres I work in for over 20 years, and I would never describe it as brittle. Quite the opposite.

  5. Duffy Moon

    Given the choice of flying on an aluminium or composite plane, I'll go for the aluminium. As we all know, early adopters are exposed to all the undiscovered faults.

    1. Anonymous Coward
      Anonymous Coward

      "Early adopters"? This stuff's been flying around in aircraft primary structure for well over 30 years. The fact that it's only now appearing in large portions of commercial airliners is down to its reducing cost and the caution of the aerospace industry, not a lack of experience.

      1. itzman

        now appearing in large portions ..

        ..is the key.

        if the whole skin is now CF, thats a BIG area to absorb sunlight, and not be especially good at radiating internal heat away

    2. Anonymous Coward
      Anonymous Coward

      @Duffy Moon

      I agree, new is dangerous. New cars are recalled too and yesterday yet an other Dremliner had to return mid flight. As for "bite Boeing on the ass". I am more concerned with my own. And as for the DC10 it was the cargo doors that opened mid flight and too down two or three planes. That was a stupid design error with the incentive of giving slightly more room in the cargo space..

      1. TeeCee Gold badge
        Unhappy

        Re: @Duffy Moon

        And as for the DC10 it was the cargo doors that opened mid flight and too down two or three planes.

        Starter for 10: Which aircraft manufacturer was it who continued to install non-plug cargo doors and fit a similarly risibly inadequate safety interlock mechanism, some time after the DC10 failures? When said manufacturer was appraised of the inadequate locking system, did they a) ground the affected aircraft to fix the problem or b) shove their heads up their arses until 9 people died when a door let go and took a big chunk of fuselage, along with a few rows of seats, with it?

    3. Yet Another Anonymous coward Silver badge

      >I'll go for the aluminium. As we all know, early adopters are exposed to all the undiscovered faults.

      I'm sticking with wood

  6. Dodgy Geezer Silver badge

    If it ain't Boeing...

    ...it ain't burning....

    Given that these planes seem to catch fire at the drop of a hat, I wonder how easy and.or costly it is to repair heat-damaged composite?

    1. John Smith 19 Gold badge
      Happy

      Re: If it ain't Boeing...

      "...it ain't burning...."

      That's a bit unfair.

      Besides "Screamliner" is better.

      1. I ain't Spartacus Gold badge
        Pint

        Re: If it ain't Boeing...

        I suspect that when the enquiries are all finished, we'll find out that Boeing bought all the flammable bendy-buses dumped by London, stuck wings on them, painted them white and is selling them on as Dreamliners.

        Now I've resolved this complex engineering problem for the world, I'm off to the pub.

  7. wolfetone Silver badge

    Echoes of the DC-10

    Readers who are old enough will recall the MacDonnell Douglas DC-10, which was a brand new innovative plane of the mid/late 70's. During it's initial release it suffered many high profile crashes because the engine would fall off. Nothing to do with MD, but more to do with crappy maintenance practices invented by the airlines to save time. It got so bad, with the negative PR, people would actively refuse to fly on the DC-10 and change to different planes, even if it cost more money. MacDonnell Douglas eventually suffered from the DC-10's early failure, and was bought by..... Boeing.

    Thing is, the 787 is an innovative airplane, and it's never been done before. Everything on that plane is checked by the FAA before it's given a certificate of air worthyness. It's not as if they're duct taping everything together and letting the plane loose.

    The cause of the fire isn't known, and wiring may be a contributor but I doubt it's the cause. Fact is, it could yet again be a battery failure, and no matter what type of wiring you have won't stop the battery being effectively shit.

    Furthermore, as far as I know, there is no one beacon on board an aircraft to see where the plane is. There are two beacons attached to the Black Box and the Voice Recorder. These last for 30 days under water. These are the only two beacons on most aircraft. So, what they're effecively saying is that either the Black Box melted or the Voice Recorder did. Which could be a problem in determining the cause of the fire.

    1. Yet Another Anonymous coward Silver badge

      Re: Echoes of the DC-10

      > Everything on that plane is checked by the FAA before it's given a certificate of air worthyness.

      Nothing on the plane is checked by the FAA - that's not how certification works, not a single FAA engineer touches the aircraft.

      They check that Boeing has procedures in place to test the aircraft and check that Boeing follow those procedures. Boeing then does the same for its sub-contractors.

      1. frank ly

        @YAAc Re: Echoes of the DC-10

        I think wolfetone is refering to the FAA airworthiness certification process for components and materials and processes, in general; and not suggesting that FAA engineers crawl around the aircraft looking at stuff.

        1. wolfetone Silver badge

          Re: @YAAc Echoes of the DC-10

          That is what I meant, sorry for the confusion.

      2. Anonymous Coward
        Anonymous Coward

        What are audits for? How should they be conducted?

        "They check that Boeing has procedures in place to test the aircraft and check that Boeing follow those procedures. Boeing then does the same for its sub-contractors."

        A process that demonstrably worked so satisfactorily with the Dreamliner batteries. Not.

        "Tick the box" based audits are great, as long as the aim is to pass the audit and get the product/service to market, rather than actually find out whether the product/service needs to be improved before it is fit for purpose.

        It's not just aircraft. UK readers who follow the news recently will have read about CQC audits, an extreme example of what happened when audits of hospitals, care homes, etc, were switched to a "light touch", de-skilled, tick-the-box-oriented system.

        1. Yet Another Anonymous coward Silver badge

          Re: What are audits for? How should they be conducted?

          The system mostly works because Boeing has quite a strong incentive not to build the next DC-10.

          And the alternative is that aircraft engineers inspectors who weren't good enough to get a job at Boeing and went to work for the government do it instead.

          Picture the staff at the DMV - would you rather have these guys specifying the design of your anti-lock brakes or an engineer at BMW?

    2. Anonymous Coward
      Anonymous Coward

      Re: Echoes of the DC-10

      My man on the inside told me that what was basically wrong with the DC-10 was that, because of advances in nondestructive testing and materials fabrication, they decided to reduce the safety factor on many components from around 2 to around 1.4.

      The problem was that for years US mechanics had got away with stupid practices because those big safety factors protected people from them.

      The car industry went though a similar phase when CAD meant that, for instance, engines should not be dismantled (breaking structural integrity) while key components were under stress. That was about the time I started to have things serviced by main dealers on the basis that they might mess things up, but they had enough assets to be taken to court.

      Even now garages foul up on replacing parts that actually need some real care - like turbochargers.

  8. Winkypop Silver badge
    Joke

    I think I'll stick with the 'tin tops' for now

    I don't have the mettle for plastic planes.

  9. seven of five Silver badge
    Joke

    Worked as designed:

    I´d suspect it worked as designed: transmitter failed, so the beacon reverted to optical signalization.

    1. TRT

      Re: Worked as designed:

      Ah. Moses code signalling. Reliable.

      1. Anonymous Coward
        Anonymous Coward

        Re: Worked as designed:

        Please stop beating about the bush and explain.

  10. BornToWin

    So once again the kneejerk reaction is wrong

    I'd have no reservations flying on any current commercial aircraft. The 787 battery deal was a fluke and has now been over-engineered to compensate for what may have actually been a slight battery manufacturing issue. That of course won't stop the clueless media from hyping every incident from a bug hitting the windshield to an uncleaned seat pocket...

    1. Anonymous Coward
      Anonymous Coward

      Re: So once again the kneejerk reaction is wrong

      The 787 battery deal may or may not have been a fluke, because as Boeing admit they don't actually know the root cause. The "solution" has been to enclose the batteries in a stainless steel dustbin so that they can burn away without setting the rest of the aircraft on fire!

  11. Anonymous Coward
    Anonymous Coward

    A lot of noise over nothing

    So it wan't the L-ion batteries at all but an issue with the ELB manufactured by Honeywell that caused the small fire. Of course this won't be widely reported like the sensational original story.

    1. Yet Another Anonymous coward Silver badge

      Re: A lot of noise over nothing

      Or it was the installation, or the new revolutionary ligthweight wiring, or the power connections or some other cause that happened to be in the same place

      6000 of the units are in service without exploding - it's suspicous that a brand new delivery of a brand new model suddenly suffers from it

  12. John Smith 19 Gold badge
    Meh

    aircraft, aircons, batteries and wiring.

    These 4 items seem to have a few problems around them. Classics include aircon under partly empty fuel tank vaporizes fuel, mixes with air (no inert gas purge system). Add Kapton wiring (which explodes rather than burns, as the USN discovered decades ago).

    Note the blog post mentioned in the article also says the electronics cooling radiator is in this area and the cooling system may not have been switched on. warm day x warming electronics x well charged battery == woof.?

    One point about carbon fibre. People have referred to engineers who cannot adjust to using it properly as treating it like "black Aluminium." I doubt Boeing engineers are like this in the main structure but you have to wonder about stuff worked on by the "B" team. Like everything you need to play to CFC's strengths and manage its weaknesses.

    The PTFE wiring business sounds very suspicious to me. I'm not sure if PTFE is naturally ductile in thin layers or if you have to add "plasticizers" to it but it's continuous use temperature is pretty high. PTFE is a carbon backbone with all the usual Hydrogen's replaced by F. That bond is strong making it tricky to melt, tricky to dissolve and very tough to burn. You have to put a lot of energy into it to get it to start reacting.

    As for the "fix" being remove an emergency locator beacon, are the others of the same type?

    This sounds like a car mechanic saying "We "fixed" the problem with your ABS. We disabled it".

    Happy driving with that.

    1. Anonymous Coward
      Anonymous Coward

      Re: aircraft, aircons, batteries and wiring.

      "the cooling system may not have been switched on."

      I think that's almost certainly "*wasn't* switched on", unless anyone knows different.

      Aircraft on ground, main engines off, APU off, ground power off.

      Assuming (!) the ELT is the culprit: these particular ELTs are out there in thousands, and don't routinely fail.

      Something was different here. It *might* have been a manufacturing defect, in which case Boeing just got very unlucky - the first observed manufacturing defect just happened to be in a Dreamliner. Oh dear. What are the odds?

      It seems more likely that some unforeseen (or foreseeable but dismissed as almost infinitely improbable) set of circumstances was involved.

      In the background is the concern that this thing caught fire and the on-aircraft facilities were insufficient to deal with the fire. Not what you need mid-flight.

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    1. itzman

      Re: Cause of accident:

      except it didn't. This is an auxiliary beacon. Nothing to do with the black box.

  14. Anonymous Coward
    Anonymous Coward

    Re. faulty batteries

    I suspect that this problem was caused by a stray particle induced internal short in the Li-metal cells, possibly a manufacturing defect similar to that in Li-Ion packs used elsewhere.

    They are routinely tested but this could have been a long term failure as the cells sit for years and are perodically impedance and voltage tested to confirm the charge is still present; if this process caused electromigration of loose particles then a KABOOM is inevitable.

    Perhaps the simplest fix is to replace *all* the Li-* batteries with safer imide technology, at least these are failsafe and thanks to the nearly solid electrolyte are guaranteed not to release flammable fumes or liquids if something bad happens.

    AC/DC

  15. JaitcH

    " it's a bit of a black eye for Boeing."

    Black scorch marks, too.

    Perhaps Honeywell can drill some holes in the airside casing so the smoke vents outside the aircraft.

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