Odds and Ends: NTSB issues 787 report today; FAA readies OK; A350-800 future debated

NTSB Report Comes Today: The National Transportation Safety Board issues its preliminary report on the Boeing 787 JAL fire today, around 11am ET.  Here is the NTSB 787 page that has been updated throughout the process. We’re traveling and may not be able to pick up the report as it comes out, so Readers, please do so and post in Comments; we’ll upgrade to a fresh post when able.

FAA readies OK for 787 plan: The FAA is expected to give Boeing the green light to begin implementing its proposed plans to fix the 787 battery issues. We expect this approval to be Friday or next week. Extensive testing will be required, but the length remains unclear. The NTSB report may or may not have implications.

Ray LaHood, secretary of the Department of Transportation (the FAA is part of DOT), still has questions. See this Wall Street Journal article via Google News, so it should be readable to all. A key paragraph:

[P]ushback against a quick final decision from Mr. LaHood—who oversees the FAA and must sign off on any package of fixes—and from regulators in Japan threatens to delay the more important resumption of Dreamliner commercial flights for months, according to industry and government officials. (Emphasis added.)

And:

A team of FAA technical experts is urging preliminary approval of Boeing’s plan, and FAA chief Michael Huerta appears likely to agree within a week or so, the officials said. That would establish a framework that could allow Boeing to begin test flights as soon as the third week in March. Results from those flights would have to be analyzed by agency officials and reviewed by Secretary LaHood and his staff before Boeing could seek permission to retrofit aircraft and seek new certification. Routine certification tests for batteries take four or five weeks, according to industry officials.

A350-800 future debated: Qatar Airways’ vociferous CEO, Akbar Al-Baker says Airbus is dropping the A350-800. Airbus says it’s not. (Also here.) Aeroturbopower has this interesting post on the subject.

Bombardier Reveals CSeries today: Bombardier will have its “reveal” of the CSeries today in a ceremony that isn’t quite a roll-out in the party-like fashion usually accompanying a new aircraft type. Rather, invited guests will visit the assembly line to see the completed aircraft. BBD isn’t taking the airplane off the production line so it doesn’t lose production time. The Wall Street Journal has this description via Google News.

51 Comments on “Odds and Ends: NTSB issues 787 report today; FAA readies OK; A350-800 future debated

  1. Oooh! Looking forward to the CSeries reveal. Cool that it’s on the factory floor!

  2. Re A350-800, QR, US and HA are high profile customers. I can see US being pragmatic in regards to their AA merger. 787-9s are on order too. HA, maybe give them a very good deal on A330s (e.g 10 yr lease) if they think A350-900 will remain to big/ expensive, so they can decide then with whats on offer at that point.

  3. Aeroturbopower’s analysis only holds weight for LCCs, such as Air Asia, which choose to put 9 across in economy class on A330s and 10 across in economy class on A350s. Not something Qatar would do.

    As for the A350-800, it’s pretty obvious that Airbus doesn’t want it to EIS before the A350-1000. That’s why they’re asking customers to upgauge to dash-900s in order not to have to pay penalty fees for late-arriving dash-800s. Better then to fully optimise the shrink model, using the latest state-of-the-art technologies that will be used on the dash-1000, and delay the EIS to 2018/2019.

    As for an A330neo, one should note that a new and heavier engine would increase range by around 10 percent — a range increase which is not needed! The A350-series will have enough range for all prospective customers. An A330neo would thus become a far more potent beast if it was re-optimised for medium range (A330-300).

    As I pointed out in an earlier comment, the A330s fuel tanks (centre tank and wing tanks) was designed with enough volume for the fuel capacity requirements of the A340-300. In fact, the A330-200 which has the same centre tank activated as that of the A340-200/300, only uses a fraction of the fuel capacity of the centre tank. However, the centre tank is obviously very useful on the A330 MRTT. 🙂

    If Airbus would shrink the centre wing box volume by around 50 percent, re-engineer the wing box inboard of the engines (i.e. similar to how the forward spar on the A380 wing box tapers from the inboard engines to the centre wing box), but without changing the outer moldline of the airfoil, significant weight savings could be achieved. In fact, the heaviest part of an aircraft is the centre section, and the A330, even how good it is, is still hampered by far a too voluminous wing box, although the entire airfoil itself is correctly sized. From the centre box to the inboard engines, there are three spars (forward, centre and aft). The A350 has done away with the centre spar, hence there’s no reason a re-engineered A330 wing with a smaller-sized centre (CFRP?) wing box should not use only two spars. By changing only the structure of the wing box and by retaining the leading and trailing edges of the wing, most of the wing-production infrastructure could still be used on am A330neo.

    By reducing empty weight along the lines outlined above and with a MTOW reduction slightly less than 10 percent — in addition to other improvements such as using A350-styled wingtips (no point in using sharklets as wing span is not a constraint for the A330) — IMO you would have a pretty good business case for a re-engining program for the A330 and using the latest state-of-the-art engine technologies. No point in re-engining with the still too heavy Trent-1000/GenX engines as they represent “old” technologies. 😉

    If MTOW is reduced by a little less than 10 percent, thrust requirements should be around 60,000 lbs and not 72,000 lbs which is the datum today. Hence an A330neo using significantly lighter state-of-the-art (PW 60000G?) -GTF engines with 60,000 lbs of thrust should have about the same payload range capability as that of the current A330s using 72,000 lbs of thust engines.

    • It’s an interesting concept. You made your description of it even clearer than last time. But it appears to me like a major rework that would require extensive, and expensive, modifications. And all with a complex re-certification process. But I suppose it might be worth it, considering the high demand for the type.

      1- Is Airbus considering that option, as you describe it?
      2- Is Pratt & Whitney interested to develop a 60,000 lbs GTF for the A330?

      • Well, the “problem” is that the current A330 is still a pretty hot commodity and that the demand for especially the A330-300 is likely to remain strong for the rest of the decade. For example, the A330-300 owns the Chinese domestic WB market – a market that is growing every year. Hence, the incentive for Airbus to do “something” is at the moment not there. By the time Airbus is ready to go ahead, the better solution might be to desig an all new composite wing, sized similar to the one described above for an A330neo, but to put it on an A350 derived aircraft instead (i.e. A350 fuselage/empennage/VTP pluss a new smaller HTP, new 787-8 sized MLG etc.).

        As for the engine, I’m sure that Pratt would be very interested in responding to a RFP for a 60,000 lbs GTF engine. Likewise with RR, which seemingly has a long term business strategy of at least competing on all WB platforms. I’m not sure about GE. It seems as if GE has made its bed with Boeing — which I believe they’ll one day regret. IMO, GE turning down Airbus on the A350 might go down in history as one of the greates business blunders in aerospace history.

      • How much recertification would it really need? Given that the MAX is still grandfathered on the original 1967 certification of the 737 (46 years ago!), wouldn’t Airbus be able to take the same approach, based on the much-newer A333 certification?

      • As for re-certification, the point is that for a re-engining programme; that’s what you’ve got to do anyway — and re-certification cost is in the hundreds of millions of dollars bracket. The additional costs for a re-engineered wing box (i.e. re-design, testing and re-jigging of the manufacturing infrastructure) would likely be in the neighbourhood of 2 billion dollars.

      • Enders said one lesson from the Dreamliner’s problems is that there may be a benefit to upgrading existing aircraft rather than embarking on entirely new designs.

        “It’s not completely risk-free” to modify existing designs, Enders said. “But it’s of course much less risky than developing new aircraft and it comes for the fraction of the cost.”

        Enders said that the European Aeronautic Defence and Space Company had not gained business due to Boeing’s problems with the 787 Dreamliner.

        http://economictimes.indiatimes.com/news/international-business/tougher-certification-after-boeing-787-woes-eads/articleshow/18853776.cms

    • In which axis do you propose to shrink the wingbox?

      In height? No, that would reduce the static height that allows large wingspan without weight penalty.

      • In the longitudinal axis.

        Please do note that the re-engineered airfoil itself would pretty much retain much of the same shape as that of the current wing (i.e. wing area, chord, trailing edge and leading edge outboard of the engines). What I’m proposing is to shrink the wing box between the two engines longitudinally. The aft spar in the centre box and in the two wing boxes would dimensionally remain the same size and be positioned exactly where they are today. On the current wing, the forward spar is positioned at the equivalent length of 10 fuselage frames forward from the aft spar (5.35m). In the re-engineered wing, the front spar would be positioned only 6 fuselage frames (3.21 m)*** forward of the aft spar while the centre spar would be removed alltogether. Then, draw a line from the new position of the centre wing box forward spar to the intersection of the engine centre-line and the forward spar outboard of the engines. That’s where the forward spar between the wing box and the engines would be positioned.

        If you take a closer look at the wing of the A380, there’s a large volume forward of the forward spars. The forward spar is canted towards the centre wing box at a very high angle. If it wasn’t designed that way, and the forward spar on the A380 had the same cant angle to the centre wing box as that of the forward spar of the A330, the centre wing box on the A380 would truly have been humungus. In the longitudinal axis it would have been some 50 percent longer.

        ***In comparison, the longitudinal length of the centre wing box of the A310 is the equivalent of 5 fuselage frames (2.68 m).

    • OV-099 agree. We discussed before. Imo a NEO could be launched if a big cargo airline wants to commit to e.g 50 A330Fs but only if itis far more fuel effient and quiet.

      The scale down of the A330 would IMO only be possible if an entirely new wing and wingbox is developed, resulting in a kind of 767XWB aircraft.. 😉

      http://i191.photobucket.com/albums/z160/keesje_pics/AirbusA330-700Light.jpg

      But if i was Airbus Executive maybe I would prefer that new wing + wingbox for a 757 class superefficient “A322/A325”, narrowing the payload-range gab from below..

      Or if I was such an executive I probably wouldn’t be able to think beyond A320 NEO / A350-900 / A400M EIS 🙂

      • An all new wing is halfway to an all new aircraft. IMO, if you’re going halfway you might as well go all the way as the ROI is usually much better. Re-engineering the A330 wing box and re-engining the aircraft would at most be a quarter of the way to an all new aircraft. Pretty doable IMO. 🙂

        As for your excellent Photobucket image, the wing box shape (dark grey) of the A330-200 is very well outlined. At the line of intersection of the dark gray area of the wing and the white fuselage, you’ll find the centre wing box. Now, reduce the length of the centre section by 40 percent (i.e moving centre wing box forward spar 4 fuselage frames aft). From the new further aftward position of the centre wing forward spar, draw a line to the most forward dark grey position of the engine centre-line. Then make a new figure with a reduced darker grey area representing the surface area of the re-designed outer wing box.

        As for your conceptual A330-700, the wing box (dark grey area) would be too big relative to the overall size of the wing. The centre wing box is longer longitudinally than the one on the A330-200. 😉

      • Well the wing of this A330-700 would be significantly smaller and flatter. Thats where the A330 carries the majority of its fuel. So a -700 would need a significant centerwingbox tank to get into a 5000NM range. It has to be light, not specially small.

        • keesje :
          Well the wing of this A330-700 would be significantly smaller and flatter. Thats where the A330 carries the majority of its fuel. So a -700 would need a significant centerwingbox tank to get into a 5000NM range. It has to be light, not specially small.

          Didnt know you were a combination of aerodynamicist, structural engineer and efficiency expert all rolled into one !!!

          Airbus needs you to explain what they are doing wrong ??? ;-P

  4. So what happens to all the A-358 orders for airlines that don’t want the bigger version? Keesje already pointed this out in his reply #3

    • As of now they persist.
      -800 being in the trailing position would allow porting of weightsaving features from the -1000 to the -800 getting away from the “plain shrink” image.

      But isn’t this just more FUD campaigning from interested parties at the moment?

    • Looking at the A350 orders list, it wouldn’t seem to effect that many airines, some of whom could easily upgauge to the dash-900. (i.e airlines already operating aircraft the size of A333s/772s). The most important airline operating aircraft no bigger than the A332s (Hawaiian Airlines) seems to be more than satisfied with the A330-200; of which they have ordered 22 units. Waiting for a fully optimised A350-800 arriving in 2019, shouldn’t be much of a show-stopper for HA.

      http://en.wikipedia.org/wiki/List_of_Airbus_A350_orders

  5. Looks like a few FACTS will come out today about what happened – but still not why.

    for BA to claim a final fix by whatever method is NOT optomistic ??

  6. Was it not last week that Leahy wanted another assembly line to cope with orders for the 350-1000? Perhaps the bean counters have a counter offer, drop the -800 and have those slots for the-1000.
    That then leaves the path clear for Airbus to do a 77X on the A330, to cover the 787-8 segment.
    Sound business to me. Less risk but still sizeable investment.

    • Yes, a 77X on the A330 without having to design an all new wing. Since you would reoptimise the A330-300 for intermediate range distance; performance-wise, you don’t really need an all new wing, just a modified “old” one that’s reoptimised and redesigned, weight-wise and fuel volume-wise, for an A330neo and not for an A340-300.

  7. Addendum.

    On the A380, the Air Generation System (AGS) is located in this unpressurised area forward of the front spar (in the wing root). Since the above mentioned re-designed wing would also provide for a relatively large A380-type unpressurised area forward in the wing root, the AGS, or other large bulky systems located in the wing-to-body fairing could be re-located to this are. Hence, the wing-to-body fairing could be redsigned as well and reduced in size, leading to a further reduction of overall drag.

    http://books.google.com/books?id=KcaYjPhRnWUC&pg=PA129&lpg=PA129&dq=a380++air+conditioning+compressor+wing+root&source=bl&ots=rkw635Z_g2&sig=UCcFkesShJ02l6GCr1U6RZscMd8&hl=no&sa=X&ei=h8c4UaOaMofQtAan-4GYDQ&sqi=2&ved=0CDEQ6AEwAQ#v=onepage&q=a380%20%20air%20conditioning%20compressor%20wing%20root&f=false

  8. ntsb:520449.pdf: “noteworthies”
    1.3 p9/10
    damaged wiring bundle from J1 ( sensors connector ) wires and also the stainless steel sleeve from excess currents while the grounding strap that burned away in Japan was intact.
    1.5.3
    protrusion on battery case cause: arcing between cell 5 body and case

  9. Ooopsie- major blooper on behalf of boeing from reuters

    and ntsb . .

    2013/03/07/us-boeing-dreamliner-ntsb-

    wherein since apu shut down cause of battery issues, no blower was available to vent fumes etc

    must of missed that on the power point presentations

    1) battery goes bonkers
    2) apu power is needed on ground to open-drive vents
    3) ap-u shut down cause battery bonkers
    4) vents dont work

    DUH!!!!!

    The NTSB’s 39-page “interim factual report” provides extensive detail on the testing performed on the battery that burned on a parked jet shortly after landing at Boston’s Logan International Airpoprt. But it also made clear that investigators remain a long way from understanding why it happened in the first place.

    Among the reports findings: a system designed to vent smoke outside the plane during a battery fire failed to function because it lacked power after the battery caught fire. The system’s auxiliary power unit (APU), a gas-driven engine in the tail of the plane, also was shut off at the time, and the battery is used to start that system.

    “As a result, smoke generated by the APU battery could not be effectively redirected outside the cabin and aft (electrical equipment) bay,” located in the fuselage behind the right wing of the 787.

    Boeing had said that the venting system failed because the plane was on the ground and lacked cabin pressure to use in expelling fumes from the cabin.

    The NTSB report marks a milestone in the agency’s probe into one of two lithium-ion batteries that burned on 787 jets in January. However, the report signaled that the NTSB has signficant additional work to do in its investigation. Japanese regulators are investigating the second incident

    ++

    of course the APU is NOT gas driven . . .

  10. What on earth were the power point rangers smoking ? POt was not legal in WA state until a few months ago

    from the NTSB report

    The main and APU battery, as shown in figure 3, consists of eight lithium-ion cells that are connected in series and assembled in two rows of four cells. Table 1 shows the specifications for the APU battery and cells. The insulation sheets provide electrical insulation and physical separation between each cell and between the cells and the aluminum battery case, which is electrically grounded. An upper and a lower fixation tray secure the position and orientation of the cells in the battery case.

    MY GOD ! Lithium and Aluminum are not compatible- especially in the presence of moisture/water- can go boom !!

    • MY GOD ! Lithium and Aluminum are not compatible- especially in the presence of moisture/water- can go boom !!

      Come down please!
      The basic cell already has a massive aluminium anode.
      and the Lithium in the cell and the case on the outside have no contact.

      much more interesting is that there was arcing inside the battery
      and heavy currents that did not take path over the grounding strap.

      • You missed my point !!
        given that energy is the product of Li and Aluminim and an electrolyte – why would anyone DESIGN a containment system- box with the same basic material ( even if a different alloy ) ??

        And of course using an aluminum ( ground ) system also makes one wonder.

        Bottom line – outsourcing the tests and compliance analysis which said the ONLY reason to get a fire will be because of OVERCHARGING ?

        REALLY ??
        http://seattletimes.com/html/businesstechnology/2020505762_ntsb787reportxml.html

        Originally published March 7, 2013 at 9:36 AM | Page modified March 7, 2013 at 12:49 PM

        NTSB: Boeing outsourced 787 battery safety analysis to subcontractors

        Among the findings in the documents released Thursday:

        • Boeing outsourced both the analysis and testing of the battery system’s safety, performed to get Federal Aviation Adminstration (FAA) certification, to its battery system subcontractor, Thales of France, and to the battery maker, GS Yuasa of Japan.

        “Theses analyses and tests were performed by Thales/GS-Yuasa and reviewed by Boeing,” the NTSB states.

        • The safety analysis by Thales and GS Yuasa determined that “overcharging was the only known failure mode” that could result in fire. Boeing therefore built safeguards into the system to “to ensure that the likelihood of occurrence of an overcharge event” was less than one in a billion — which is the usual FAA standard in providing for potentially catastrophic events.

        However, there is no indication in the NTSB documents that the battery that caught fire was overcharged.

      • Relating to the chemistry I missed your point because it does not exist 🙁

        What I am still missing is infornation on which potential the cell body is sitting on: Anode, Kathode (or floating?no)

        Noteworthy is the requirement for the cell bodies to be isolated from each other and the case of the box and what materials have been used.
        PVC for isolation is unusual, overheating/burning will release hydrogen chloride.

        Still the use of an eclosure design adequate for nonexpanding nylon vessel NiCd cells for conductive and potentially expanding Li-Ion cells was less than brilliant.

        Still wonder who’s idea this was.

        Apropos found some doc that shows how Saft designs enclosures ( and ancillary systems ) for their cylindrical cells:
        http://www.doc-center.robosoft.com/@api/deki/files/2791/=Manuel_UtilisationVL41M72V39Ah.pdf

        • Uwe—-Still the use of an eclosure design adequate for nonexpanding nylon vessel NiCd cells for conductive and potentially expanding Li-Ion cells was less than brilliant.
          Still wonder who’s idea this was….

          But it was cheap and from somewhere in the report made of .063 aluminum sheet!

          And having the emergency flight control battery above a main battery is pure stupidity- even in flight- heat rises and so do flames !

          I’m sure it looked neat and efficient and saved 1/4- to 1/2 pound of extra wiring !!

          designed by an MBA and an Personal computer geek, approved by an artist- and presented in thrilling power point colors to a Board made up of helath care providers and GE wannabees.

          Looks as if no sneak circuit analysis- and perhaps should have gotten a local industrial power types involved – the ones who keep your house power runnning 24/7 and know how to handle large numbers of AC power along with starter generators

      • I also think Don misses the point.

        The batteries use lithium ions in the electrolyte and aluminium electrodes… this has absolutely nothing to do with the aluminium battery box. The potential difference between the metals is part of what makes it a battery.

        It’s not like there’s a chunk of lithium close to a chunk of aluminium somewhere outside the battery casing…!?

        • SomeoneInToulouse :
          I also think Don misses the point.
          The batteries use lithium ions in the electrolyte and aluminium electrodes… this has absolutely nothing to do with the aluminium battery box. The potential difference between the metals is part of what makes it a battery.
          It’s not like there’s a chunk of lithium close to a chunk of aluminium somewhere outside the battery casing…!?

          well now consider when ONE cell burst diaphram opens up , vents electrolyte all over and produces a certain amount of heat, etc.

          Heard of domino theory ??? Or cascading failure- or for want of a nail a hjorseshoe was lost, for want of a horseshoe a horse was lost and …..

          Boeing made a big deal of puncturing ONE cell with a nail and getting a bit of smoke.

          Now mention of doing it in an enclosed thin aluminum box with cells tightly packed and steill active with lots of ‘energy”…

          • Well, nailing the cell obvious was the unsuitable method applied to an unsuitable object.
            With the nail put through the enclosure was already breached..

            And yes, bringing High energy switched power electronics together with more sensitive electronics is a PITA. One P in that A is raised ground potential from high currents in the ground return. And the Dreamliner seems to be rife with Power converters connecting the various busses forwards and backwards.

          • Interesting . . ..
            go to

            http://dms.ntsb.gov/public%2F54000%2D54499%2F54251%2F520314%2Epdf

            E.3.3.3 BATTERY CASE GROUND WIRE
            The wire had been cut by fire fighters for extrication of the battery case from the airplane and both halves were examined at the NTSB Materials Laboratory.
            The green battery case ground wire had been routed along the front of the battery case past where the W504014 wire bundle had separated from the J1 connector.21 The green ground wire had been extensively fire damaged in the area where the J1 connector had been badly burned. (See Figure 17)
            The portion of the ground wire that had been attached to the avionics rack ground point was also found to exhibit heat damage. In the laboratory, the insulation of the green battery ground wire was cut open where the exterior was undamaged. The inner surface of the insulation was found slightly blackened and brittle to the point of cracking when flexed, consistent with resistance heating by electrical current applications beyond what the wire had been designed for. (See Figures 22 and 23)
            Figure 22. Battery case ground wire
            Figure 23. Inner surface of the battery case ground wire, in an area that was not thermally damaged on the exterior. View shows the white plastic has blackened plastic and become brittle.

            page 31

            seems that a very small ground wire had high current . . . . .

            But look at the money they saved by not using an IRON BIRD system ( All systems and wiring and motors and . . .) put together in approx space- location forms but in a building and bucu tests and instrumentation because it is expensive !!!!!

          • see my post “noteworhties”:
            http://leehamnews.wordpress.com/2013/03/07/odds-and-ends-ntsb-issues-787-report-today-faa-readies-ok-a350-800-future-debated/#comment-34231

            The cable harness attached to J1 ( sensors ), going to the charger shew significantly more damage than the grounding strap. ( grounding strap is for tying to a potential and not for taking currents, anyway )

            Imho this could indicate that the battery rack and the charger were on distinctly different ground potentials.

      • But Don, you were talking about lithium and aluminium as being incompatible… what’s that got to do with cascades etc.? You realise the electrolyte is made up of (amongst others) lithium *salts*, right? There’s no pure lithium involved, which seems to be what you’re worried about. If that firefighter had been splashed with hot molten lithium I doubt he’d be around to discuss it with the NTSB afterwards.

        Tightly packing energy dense cells with no cooling or individual cell monitoring is asking for cascades. On that we agree.

        • SomeoneInToulouse :
          But Don, you were talking about lithium and aluminium as being incompatible… what’s that got to do with cascades etc.? You realise the electrolyte is made up of (amongst others) lithium *salts*, right? There’s no pure lithium involved, which seems to be what you’re worried about. If that firefighter had been splashed with hot molten lithium I doubt he’d be around to discuss it with the NTSB afterwards.
          Tightly packing energy dense cells with no cooling or individual cell monitoring is asking for cascades. On that we agree.

          Its been stated that the firefighters did not know LI was involved. Although it makes a poor battery- its very likely that LI- salts and Aluminum in a hot environment will generate some chemical reaction releasing perhaps hydrogen , etc. And if the mess is hot- putting water on it makes it worse- When the fire crew found that powder did not work- they used halon- bucu amounts for a long time, etc. So my point was- why use a known material – aluminum- thin gage- to contain a possible mixture of Li bearing electrolyte which if nothing else will over a period of time with a small leak corrode or cause an unwanted chemical reaction ?

          The answer is – noone minding the store

          And now they seem to be using a stainless steel or possibly titianium or ? case, muichm thicker.

          By the way – Hot salt solutions in general are not usually compatible with most titanium alloys.- dont know about li salts specifically

  11. and exactly from the NTSB report page 32

    Boeing’s 787-8 electrical power system safety assessment also included an analysis of lithium-ion battery cell failure modes. This analysis determined that overcharging was the only known failure mode that could result in cell venting with fire. As a result, Boeing established additional design requirements to ensure that the likelihood of occurrence of an overcharge event was extremely improbable.48 Boeing further determined that cell venting without fire could be initiated by several different failure modes, including external overheating, external short circuiting of appropriate impedance, internal short circuiting, recharging a battery that has been overdischarged, high-rate charging, or charging at cold temperatures.

    great analysis !!!

    To evaluate the effect of cell venting resulting from an internal short circuit, Boeing performed testing that involved puncturing a cell with a nail to induce an internal short circuit. This test resulted in cell venting with smoke but no fire. In addition, to assess the likelihood of occurrence of cell venting, Boeing acquired information from other companies about their experience using similar lithium-ion battery cells. On the basis of this information, Boeing assessed that the likelihood of occurrence of cell venting would be about one in 10 million flight hours.
    Boeing used the results of its analysis and tests to incorporate several safety features inside and outside of the battery that were designed to prevent the conditions of cell venting and cell venting with fire. These features included thermal protection devices, circuitry to monitor cell and battery voltages and temperatures, circuits to ensure that all cells in a battery are charged equally and within safe voltage limits, and components and circuitry that discontinue charging of the battery when conditions warrant this action.

    OOOPs forgot to divide by 2 or 200 or whatever

    But I’ll bet the powerpoints looked neat !!

  12. “Routine certification tests for batteries take four or five weeks, according to industry officials”
    But is this really a certification test of the battery? Due to the circumstances, this should be far from routine. Also, the biggest question at hand, is this really a certification? The planes were grounded through an AD. Theoretically, no certification or recertification is required.

  13. SomeoneInToulouse :
    That document is showing a lot of electrical and heat damage away from the battery itself. Certainly seems to contravene the rules concerning no damage to rest of EE bay. I wonder why none of this was in the other recent presentation and update!

    My guess is the cabling damage ( at least the J1 harness ) precedes the burn damage.
    given cause: _resistive_ heating : wires _and_ the stainless mesh covering/shielding
    going to J1. The report has no word on sequence !?

    • Uwe :
      Well, nailing the cell obvious was the unsuitable method applied to an unsuitable object.
      With the nail put through the enclosure was already breached..
      And yes, bringing High energy switched power electronics together with more sensitive electronics is a PITA. One P in that A is raised ground potential from high currents in the ground return. And the Dreamliner seems to be rife with Power converters connecting the various busses forwards and backwards.

      Somewhere in one of the few documents I have scanned was mention of the problems using a resistive load to simulate apu starting – versus actual apu starter generators, and the discovery of rapid changing from load to charge etc during the starting cycle

      Got me to thinking ( which is by some accounts dangerous 🙂 )

      I have a mid sized RV which uses an VERY old design generator ( kohelor) of about 3 Kw – 110VAC capacity. It uses a combo starter- generator running off a 12 volt battery.

      After it starts – and is running at correct speed for 60 cycle output – it takes somewhere around 10 seconds before AC power is available on RV wiring. At the same time ( I haven’t checked exactly ) it produces 12-14 volts DC to recharge batteries.

      Thus the voltage output is ‘stable” (more or less) BEFORE coming on line.

      I mention this, because what the 787 system **seems** to do is allow powering the AC/DC convertor OR DC charging bus to come on line even while starting the APU- thus the rapid change between load and charge noted.

      Makes me wonder if the computer design mensas ever bothered to do the same thing on apu or engine start- which is to build in a xx second delay AFTER starting before going ON LINE.??

      Large swings in large power systems can do bucu damage- both at home and in airplanes.

      To go a bit further along this line – I also note that when I had my home power panel ( 220 vAC ) updated to code ( it was 50 years old ), the requirement was to ground EVERYTHING.

      Since I had/have copper water lines and sewer lines the result was the electrician ran multi stand 1/4 inch dia copper cable to water lines- natural gas lines-sewer lines, and then tie into TWO new 8 foot buried ground rods about 8 feet apart. This in addition to the standard ground line coming into the service entrance.

      I guess its both for lightning protection and to ensure ALL grounds are at same potential.

      Which doesn’t seem to be the case on the 787. ?

    • UH OH- BA pulling a fast one ??
      http://www.speea.org/index.html
      Boeing to close Seattle flight simulators

      In a hastily scheduled, listen-only, teleconference, The Boeing Company today announced the closure of all flight simulator services in Seattle.

      The removal of these services will negatively impact engineering functions. Boeing 787 engineering will be impacted first as the company intends to move 787 simulators “immediately.”

      Industry experts predict up to 10 months downtime to move simulators to Miami, reconfigure them and get FAA recertification. Taking the 787 simulators off line indicates that Boeing leadership expects the 787 fleet to be grounded for a substantial period of time.

      Pilots and instructors in the Airplane Manufacturing Pilots Association (AMPA) are meeting at SPEEA Tukwila headquarters today at 2 p.m.

  14. Amusing, “can’t stop pimping the image”

    Forbes reports that orders for the 787 continue despite problems.
    As Air Berlin is reported to have ordered 15 Dreamliners just now.

    contrast with:
    Air Berlin ordered 15 in 2007 has lots of problems
    currently ( just survided having Mehdorn)
    What one findes in German mendia is that they are contemplating
    shifting their order (fully or partial) to 787-9 getting around
    problems on AB’s and BA’s side.

    no wonder the share value performs well.

      • yes, forgot that.
        Anyway the fascinating aspect is a fake sales notice to
        compensate investigation effects just ahead of the weekend gave a boost of 2 dollars.
        A correction will be old news on Monday, so that boost will
        persist a bit.

      • “Fake sales notice”, lol… more like good ‘ol sloppy journalism. Looks like BA’s stock closed flat today. I’m surprised to see the NTSB report didn’t do more damage though.

      • See!?
        That is why i think it is floated misinformation and not sloppy journalism. go back in time and you will find a trail of those “sloppy” floaters all around. ( In the same vein you wil find a trail of sloppy “sinkers” on Airbus reporting. The playing field is level because someone continuously tilts it over to one side.)

    • Do a google at “Seeking Alpha” in combination with Boeing. A ever stopping stream of news Boeing is doing great whatever and now is the right moment to buy. I do not know who’s behind it but they are obviously getting away with it. Everybody wants to be excited by Boeing stock and they get the news they want. Everybody happy.

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