Quoting RickNRoll (Reply 144): Doesn't it take a long time to get those new numbers?

It will be impossible to predict such a time frame. Therefore the fix will have to be done differently, by rearranging the branches on the fault tree.

That's doable. The really big problem is not that batteries can fail, even if that probability of course shall be minimized. The real issue is that a battery failure can cause collateral damage. The latter is the really touch words from FAA ("could" etc.), and it doesn't need to be the case.

The batteries will be removed from the EE-bays. Their failure mode has proved incompatible with other equipment in there.

Just add turbulence and negative G to the fault tree, and we have the battery goof all over.

The FAA won't accept that. Other CAAs overseeing non-US carriers won't accept that. The airlines won't accept that.

Add to that, this is close to an unparallelled world wide PR disaster. Boeing used the internet and social media to market this plane as the plane of choice ("jet lag free", etc.), and it so far backfired. If they had instead told that they made another plane, bigger than the 737 and smaller than the 777, then... They cannot un-invent the internet. They can only recover by taking a technical action which is clearly explainable to the non-technical public.

It may wipe away the weight advantage over older and proven systems. But just look at the alternative.

Quoting Cubsrule (Reply 147): Maybe. I cited the Toyota recalls in 2009 and 2010 as a good recent example of a different part of DoT running amok, and the stop sale in early 2010 was the functional equivalent (for cars) of a grounding. AFAIK, no one at NHTSA lost their job over how that was handled.

I would consider those recalls to be nothing in comparison to this. Cars and airliners are not really analogous other than the fact that they are both transportation.

There was a stop sale. The issue was fixed. Toyota moved on. Toyota was also very responsible and very attentive to getting the recall notices out there and performing the required actions. At no point did I feel like Toyota was trying to minimize the issue. Rather, people were faking accelerator malfunctions and brake malfunctions to try to get money out of Toyota.

And... a plane crash (or the mere suggestion that there's a risk of one) is different from a car crash in the same way that Hurricane Sandy was different from a bit of rain.

This situation is so different, it's not even comparable.

And car recalls happen all the time.

Quoting DocLightning (Reply 151): There was a stop sale. The issue was fixed. Toyota moved on.

Stop sales are pretty rare (sort of like groundings). Recalls are more like ADs - frequent and not usually newsworthy (for instance, practically no one in the mainstream media is talking about the fact that the new Ford Escape has been recalled four times in a matter of months, including a couple of times for issues that can cause fires). That's why it's an interesting comparison.

In hindsight, the stop sale was absolutely the wrong decision, for there was nothing serious wrong with any Toyota vehicle and absolutely nothing wrong with the vast majority of Toyota vehicles -- those without all-weather floor mats and without the accelerator pedal at issue in the second recall. DoT acknowledges that it was bungled, but there's been no public fallout at the agency. What makes you think that a determination down the road that the 787 grounding was somehow handled incorrectly (either started or ended at the wrong time) would have any different effect?

Quoting DocLightning (Reply 151): I would consider those recalls to be nothing in comparison to this. Cars and airliners are not really analogous other than the fact that they are both transportation.

Fully agree. Besides a stop sale is not the same as a grounding: Toyotas were not taken off the road. It is much more analogous to an AD.

http://www.thedenverchannel.com/news...ents-on-boeings-new-787-dreamliner


So I ran across this article that may shed some light on the 787 dilemma. Just as interesting, since the 787 is the first of its kind and there is no other plane to compare it too, how does the FAA properly diagnose the problem(s) so that it won't happen again?

Quoting DocLightning (Reply 151): There was a stop sale. The issue was fixed. Toyota moved on. Toyota was also very responsible and very attentive to getting the recall notices out there and performing the required actions. At no point did I feel like Toyota was trying to minimize the issue. Rather, people were faking accelerator malfunctions and brake malfunctions to try to get money out of Toyota.

Sorry to go off the 787 topic, but wasn't the root cause found to be the driver side floor mat could bunch up and jam the bottom of the accelerator pedal? And gosh, no driver on earth would realize the safe way to stop the acceleration of a 'runaway car' is accomplished by turning the ignition key OFF. Now, if turning the ignition off or selecting neutral on the transmission didn't stop the car from accelerating, Toyota would be responsible for an unsafe design. But as it was, Toyota went over and above what was necessary. As to the 'fakes' Doc mentioned, I remember one Prius driver who was on the news stating his car accelerated wildly out of control to 120 MPH. A Prius accelerating wildly out of control to 120 MPH? Give me a break! In the forty or fifty second yawn-fest that ensued getting up to that speed (if a Prius is actually able to go that fast), it never occured to the driver to select neutral or kill the ignition? Hopefully they crawled back under their stone.


Back to the 787... I must admit I am a life-long Boeing fan, and I am very concerned about the 787 devastating their reputation, from an airline standpoint and from a passenger standpoint. With all the negative publicity, will anyone ever really trust the outcome of the investigation, even if they announce they have found the fault?

The 787 jabs are already going around:

''ScreamLiner'', ''Boeing Broiler'', ''Come Fry with us'', ''Arrive alive in aluminum, or perish in plastic''

Quoting DocLightning (Reply 145): If the aircraft flies again and there is another major issue, either with this battery or with another system, the aircraft will be grounded again. And if that happens, it could essentially mean the end of the 787 program. It would be, AFAIK, unprecedented in commercial aviation history. So they'd better be very sure that they have it right this time around.

I really feel bad for the employees who worked so hard on this project, only to have it become a PR nightmare. Air Canada was planning to add the B-787 to their fleet next year, now I wonder if they still want to?




✈ LD4 ✈

[Edited 2013-01-20 19:54:36]

Quoting sankaps (Reply 154): Fully agree. Besides a stop sale is not the same as a grounding: Toyotas were not taken off the road. It is much more analogous to an AD.

The analogy is important (but imperfect) because of how rare both events are. The fact that NHTSA deals with recalls on a daily basis doesn't really prepare them to handle a stop sale.

Similarly, the fact that FAA handles ADs on a daily basis doesn't prepare them to ground a type. I am confident that in hindsight, we will all find much to criticize in how FAA handled this grounding, but that's the nature of the beast.

Quoting Skydrol (Reply 156): Air Canada was planning to add the B-787 to their fleet next year, now I wonder if they still want to?

Seems as if a year ahead will give them time enough to plan around this, by then something will have been found to get the type back in the air and that's the important part in the long run even if passenger perception does suffer a bit. I figure the carriers that were getting them, adding more, or starting destinations in the next few weeks/months would have more to worry about.

Quoting rotating14 (Reply 155): http://www.thedenverchannel.com/news...liner

The end of this article is pretty damning against the FAA:

"In other words: the investigation is becoming a lot more complex than expected, which will likely delay the Dreamliner's return to the air.

But there's a bigger picture here: The complexity of this problem is also raising questions about whether the F-A-A is equipped to oversee such sophisticated technology.

The FAA failed to detect these problems in its original inspection process."

There were 'special conditions' in the certification process which the 787 had to adhere to. What possible problems in the design did the FAA fail to detect?

Quoting AeroWesty (Reply 159): There were 'special conditions' in the certification process which the 787 had to adhere to. What possible problems in the design did the FAA fail to detect?

No doubt that when they find it, 14 CFR Part 25 (transport category certification rules) will be a few paragraphs longer  

Quoting AeroWesty (Reply 159): The end of this article is pretty damning against the FAA: "In other words: the investigation is becoming a lot more complex than expected, which will likely delay the Dreamliner's return to the air. But there's a bigger picture here: The complexity of this problem is also raising questions about whether the F-A-A is equipped to oversee such sophisticated technology. The FAA failed to detect these problems in its original inspection process."

The FAA may be a little behind the times in their knowledge, and lithium cells are pretty new in airliners. I don't think the problem is too complex for them to come to understand, but perhaps they don't understand it as well (yet) as they need to. Certainly a lot of people at NTSB and FAA are getting crash-courses in lithium technology over the past weeks, and you can bet that additional policies, procedures, regulations, etc. will result with a net increase in safety for all.

In some ways, it seems a little similar to me as the square window problem in the Comet. Metal fatigue wasn't particularly well understood at the time, but they did their best with testing, went above and beyond the norm of the day; but the end result was that there were still unknowns that lead to some catastrophic failures. I think it is unlikely that the 787 will take the same path as the Comet; but there are similarities in the learning curve. Further, I do expect all the hulls currently built to be back in the air - but there will be modifications, no doubt.

Quoting KELPkid (Reply 160): No doubt that when they find it

The investigation has barely begun. If I'm reading things right, it's still possible that the design is solid, but the execution of it was faulty. Or is that completely off the mark?

Have been travelling, very late to the party. Picking up some stuff from the prior threads:

"Am still hoping Tdscanuck or CM will comment in whether or not atmospheric pressure changes might have a role.. (See post 1)"

Possible, but heavily tested so unlikely.

Quoting art (Reply 7): Could any of the cognoscenti hazard how long the grounding will be if it is determined that the problem is "simply" manufacturing defects in the batteries concerned?

Best case is they discover a manufacturing defect that's detectable...then they just have to inspect the fleet batteries for the defect and clear those that don't have the defect. An approximately similar thing happened with 737NG fuel pumps several years ago (they had to be X-rayed to make sure some internal wires were in the right place). That could be done on the order of days/a few weeks.

Quoting Aesma (Reply 15): The basis for certification is that many kinds of failures can happen, without downing the aircraft. If we now discover failures that were not predicted, all bets are off.

cornutt summed this up far better than I could. Failures that weren't predicted are very bad, but this isn't a failure that wasn't predicted. It's just that the failure probability might be way off...this is also bad, but considerably more tractable than unanticipated failure modes.

Quoting PW100 (Reply 16): Can't we all just agree that in the view of the regulators (FAA, EASA etc), anything supposed to be airborne that has not been demonstrated to be safe, is by definition unsafe?

No. That's not how the regulations work. Under that system, nothing would ever get certified.

Quoting francoflier (Reply 27): in flight fire is never, ever something where you can say there is no risk of losing the aircraft. Especially when it happens in an inaccessible area with little fire protection/fighting capability.

Although it's true that you can never say there is *no* risk of losing the aircraft, you can estimate how likely it is for a fire to result in loss of the aircraft. In this case, since a battery fire was a design condition, the probability of a catastrophic event is still very very low. That doesn't make fires acceptable, in any way, but it does moderate the gap between likelyhood of a battery fire and likelyhood of a hull loss.

Quoting RickNRoll (Reply 55): Not wanting to be a pain, but it only fixes the problem of the batteries failing as they have recently. They still need to address the issue of containing a battery adequately when it does fail.

So far, the existing events have demonstrated that the containment *does* work.

Quoting JoeCanuck (Reply 60): My opinion is that these Li-ion batteries, (and batteries of similar chemistry), are unsuitable for high power applications on aircraft. The probability of failure and the difficulty in predicting failures, as well as the violent way they fail, raise them above the level of acceptable risk.

That's not necessarily true; you could assume the probability of a battery fire is 1, then modify the containment to still keep the probability of a catastrophic event to be extremely remote. This is, obviously, not what will actually happen but risk gets assessed at the aircraft level, not the component level, so component reliability doesn't directly inform what acceptable risk is.

Quoting bonusonus (Reply 69): How and when does each type of battery get charged? And how much recharging is typically required in each?

Both batteries are charged anytime the airplane system is energized by another source (ground power, engine generators, or APU) until they're full, then they're just periodically checked. Since Li-ion doesn't discharge quickly when not used, they'll basically just sit there until they experience a current draw again. Since 787's like to stay powered up, any carrier that keeps them on ground power may never be charging the battery in any significant way.

Quoting KC135Hydraulics (Reply 82): If a pickup-sized Diesel engine requires upwards of 700 cranking amps to turn over, imagine the instanteous draw from the electric starter on the 787's APU. It has to be quite high.

Not so bad...700Ax12V = 8400W. The 787 APU doesn't have a load compressor so it's only operating at very low power when starting and the battery is at higher voltage...I suspect it's actually pulling a lot less than 700A.

Quoting sweair (Reply 90): So to repeat my question, would or could a fuel cell fueled by Jet-A be safer than a battery?

Could? Yes. Would? Unlikely.

Quoting sweair (Reply 90): They create heat, but has there been any serious incidents with fuel cells?

I think fuel cells have melted down, but the problem is usually around the fuel or reformer rather than the cell itself.

Quoting packsonflight (Reply 92): The 787 did not contain the battery failure properly. As far as I can see this is a fact, and Boeing definitely have to make some hardware changes here and get them certified.

How is this a fact? In both cases, the battery fire was contained and no other equipment was taken down in the process. Isn't that the containment requirement?

Quoting teme82 (Reply 113): Quoting WingedMigrator (Reply 111): That much is easy. 32V x 65Ah = 7.5 megajoules I think that is more than enough to cause serious issues with the aircraft. If all the batteries would fail at the same time it would be really bad day for that plane and it's occupants.

The batteries aren't co-located and both battery areas are designed to contain the full energy of a battery fire indefinitely. It would be very very bad from a reliability standpoint but, at least based on the current facts, wouldn't present a danger of loss of the aircraft.

Quoting F9animal (Reply 116): The plane is grounded because it is not safe.

No. The plane is grounded because the regulators don't feel that Boeing has adequately proven that it meets the requirements. It is absolutely true that the regulators will ground a plane that is unsafe but that's not the only reason.

Quoting F9animal (Reply 116): A fire from a battery is dangerous. Stop downplaying it, because it is what it is.

I agree it shouldn't be downplayed, but it also shouldn't be up-played. Fire is dangerous. Fire in an area designed to contain a fire, however, is a heck of a lot less dangerous than fire in an area not designed for it. This is *the* major difference between these events and Swissair111.

Quoting RickNRoll (Reply 144): Doesn't it take a long time to get those new numbers?

You can always put them up to 1 and see how that impacts the rest of the fault tree; this is conservative and gives you an idea of what the allowable range of numbers is.

Quoting WingedMigrator (Reply 146): Since the time for the battery to combust itself totally is far less than the certified ETOPS time, is it not a condition for certification that the battery be allowed to combust itself totally, in flight, without endangering life?

Yes.

Quoting prebennorholm (Reply 150): The batteries will be removed from the EE-bays. Their failure mode has proved incompatible with other equipment in there.

How so? What other equipment stopped functioning?

Quoting Skydrol (Reply 156): With all the negative publicity, will anyone ever really trust the outcome of the investigation, even if they announce they have found the fault?

Well, at least one person will. I suspect I know others.

Tom.

It does appear that everyone, the FAA included, has lost some perspective here.

The biggest concern of the pundits (and by extension, the public) at the outset was the extensive use of CFRP in the hull and wings.

Remember how everyone freaked when they saw those wings bend up on takeoff? Surely that can't be safe, right?

Turns out that on this whole ship, in its production version, the thing that has grounded it (other than politics) is a freakin' battery. Something that, at the end of the day, is barely-necessary. And something that they spent seven years designing and testing. And something that still, as far as I can tell, even with a complete failure of the battery [i.e. ignition] never posed a safety of flight issue and never spread beyond the containment. To my mind, this occurrance is many orders of magnitude more safe than a contained single-engine failure (i.e. blade off) at climb thrust, which is an event that gets no notice in the mainstream press when it occurs.

Since there is no effective extinguishing agent other than burying it, how about they just attach the thing to a parachute, mount it on a hatch, and if it catches fire...poof! Overboard it goes.   Frankly, just as sensible as evacuating an aircraft on the runway when there is no indication of fire or actual smoke, as ANA did. Hysteria much?

All aircraft have batteries. All batteries have the possibility of thermal runaway. Didn't someone say that they're next to the loo on the KC135? Plainly, this is a problem that can be solved in the long run. The only thing that is sad to me is that, without any demonstrated effect on safety of flight, the plane has been grounded while the problem is being solved.

[Edited 2013-01-20 21:35:08]

Quoting Cubsrule (Reply 157): Similarly, the fact that FAA handles ADs on a daily basis doesn't prepare them to ground a type. I am confident that in hindsight, we will all find much to criticize in how FAA handled this grounding, but that's the nature of the beast.

Two aircraft in a 72-hour period had an onboard FIRE (no, I am not backing down from that word). It might have been contained. It might have been slow. But it was combustion where there should be none. Both fires were in the same component and there were only about 50 frames in service on this brand-new type. Darned right it should be grounded. The only "mishandling," if any, was that it took the FAA until the next day to ground it.

Quoting AeroWesty (Reply 159): But there's a bigger picture here: The complexity of this problem is also raising questions about whether the F-A-A is equipped to oversee such sophisticated technology.

Fair enough point. But then again, the FAA does not design the aircraft or make it safe. The OEM (Boeing, in this case) does that. The FAA is not at fault for the primary failure. I will point out that the OEM also failed to detect these problems during testing. The FAA is only in charge of enforcement.

Quoting AeroWesty (Reply 162): If I'm reading things right, it's still possible that the design is solid, but the execution of it was faulty. Or is that completely off the mark?

there is no yes or no to your question... just a maybe/maybe not...
The problem with wanting to state absolutes now before the final answer is avai is people with other answers rather than accept, will argue conspiracy and coverup.. or political intention.

one of the advantages of being old, is we recognize that there is more we don't know than what we do know.

Quoting kanban (Reply 110): The NTSB reported on Jan 20th 2013 that a first examination of the flight data recorder of JA829J showed the nominal battery voltage of 32V has never been exceeded. The battery, powering the APU for APU startup, has been disassembled into its 8 cells for detailed examination and documentation, 3 of the cells were selected for further disassembly and examination of cell internal components.

Thanks, so we now know that a single cell died and did run away thermally. I also have to say that 8 cells is not much for such a high capacity. Why the selection of high currents instead of higher voltages?

We also must assume now, that the charger seems to have failed (we do assume, that it has a balancer).

It is the chargers responsibility, to deal with each single cells and prevent it from becoming hot.

Quoting KC135R (Reply 130): It seems (if I read the current info correctly) that the JAL battery DID NOT exceed "max" voltage and the ANA battery did.

Max voltage is meaningless as explained by me and much more in detail by nm2582.

Quoting iahmark (Reply 131): Even though it appears the voltage limit wasn’t exceeded in the case of the battery that caught fire in the Japan Airlines 787 in Boston

Dito.

Quoting JoeCanuck (Reply 134): I haven't seen the specs of the 787 batteries but 32v is probably the nominal voltage value, rather than the full charge value...which could be 38v or even more.

Usually cellNumber x 3.7V is considered as nominal. 4.2V is the ultimate max voltage (for lipo, there are other types of lithium batteries with slighty different voltages). Above that (and it is a very tight tolerance), the cell swolls and starts overheating. So 38V can never be reached without fireworks with 8 lipo cells.

So what we know is:
- The regulatory requirements demanded, that no cell would ever heat up to unsafe temperatures -> that requirement was broken. So there must be flaw. There is a gap how the system performed, and how it should have performed.

- The technical solution to prevent that, would first be a balancer and second a cell temperature monitoring. I do assume, that both capabilities are build into that charger (anything else would be culpable and fully warrant the grounding).

- But one of these two solutions failed. Possible reasons:

- Wrong wiring in the balancer.

- Defective electronics. But we read, that these systems exist redundantly. But still, there are single points of failures e.g. in the area of the amplifier, that generates the charging current per cell.

- Undetected criteria. E.g. low cell temperatures, as they could happen often inflight, change the characteristics quite a bit. Are all the effects on the battery coming from environmental influences modelled correctly in the charging system?

Quoting DocLightning (Reply 165): Fair enough point. But then again, the FAA does not design the aircraft or make it safe.

What you quoted from my post was what I was quoting from the article (the reason why it was enclosed in quote marks and set in italics).

Quoting DocLightning (Reply 165): I will point out that the OEM also failed to detect these problems during testing.

Which problems? In the design or execution of the design?

Quoting kanban (Reply 166): there is no yes or no to your question... just a maybe/maybe not

That's what I was thinking. We just don't know enough yet to be damning towards any part of the process, expressed well by tdscanuck in his recent post quoted below. We don't know what failure it is yet that needs correcting.

Quoting tdscanuck (Reply 163): The plane is grounded because the regulators don't feel that Boeing has adequately proven that it meets the requirements.

Quoting wjcandee (Reply 164): The only thing that is sad to me is that, without any demonstrated effect on safety of flight, the plane has been grounded while the problem is being solved.

We have to have confidence in the FAA. If they deem the aircraft potentially unsafe to fly, we have to accept their opinion, and stop second guessing them.

When they deem the aircraft safe to fly, we have to accept their opinion and not second guess them as they know far more than we will ever do.

Quoting wjcandee (Reply 164): the thing that has grounded it (other than politics) is a freakin' battery.

Politics didn't ground this aircraft - if anything there is political pressure in the other direction, as Boeing is part of the fabric of the US economy.

Quoting Skydrol (Reply 156): With all the negative publicity, will anyone ever really trust the outcome of the investigation, even if they announce they have found the fault?

Me, I have total confidence that the 787 will continue to be a safe, competitive, value for money aircraft. If it takes one more month to ensure that, so be it. It will be forgotten about in twelve months when the media circus is onto something else.

Quoting Skydrol (Reply 156): ''ScreamLiner'', ''Boeing Broiler'', ''Come Fry with us'', ''Arrive alive in aluminum, or perish in plastic''

Sticks and stones may break my bones.....

We are lucky then the aircraft are bought by bean counters who read the New York Times, China Daily or the Economist, rather than some sensationalist rag of a 'newspaper'

Having been involved in a lot of engineering to try to determine a design failure mode....but never with a battery...I'm guessing that a sharp engineer will postulate a cause for the failure, they will start with a new battery with this deliberately created fault, and they will test it to failure maybe accelerating the test conditions. They can't take a year to test for failure.

I doubt they will learn anything from the two charred batteries.

Quoting DocLightning (Reply 145): It's very disconcerting that Boeing is in denial about the word "fire."

Quoting DocLightning (Reply 165): Two aircraft in a 72-hour period had an onboard FIRE (no, I am not backing down from that word).

Doc, I get it that you do not like what Boeing has said (or has not said) in their public communications about the two battery fires. What you may not realize is that once the NTSB opens an investigation into any accident or incident, all public comments on the subject from the OEM are dictated by the NTSB. Boeing cannot legally comment on the battery issue beyond a set of statements which are entirely controlled by the NTSB.

Quoting CM (Reply 171): Boeing cannot legally comment on the battery issue beyond a set of statements which are entirely controlled by the NTSB.

I cannot believe that even for a second. They might be strongly discouraged from commenting, and even further discouraged by the possibility of inadvertent self-incrimination, but legally barred? No such law on the books.

Quoting WingedMigrator (Reply 172):

Every time the NTSB opens an investigation, the instructions to Boeing are made crystal clear by the NTSB; there can be no public communication on the subject without the NTSB having the final right or review, edit or reject the communication, with the NTSB typically providing direct guidance on what to say and when to say it. I don't know if it is a matter of legislation or not, but for all practical purposes it may as well be. Any time there is an active NTSB investigation, they are dictating what the OEM can and cannot say about the matter.

Quoting AeroWesty (Reply 162): If I'm reading things right, it's still possible that the design is solid, but the execution of it was faulty. Or is that completely off the mark?

Yes, that's a possibility.

Quoting wjcandee (Reply 164): Since there is no effective extinguishing agent other than burying it, how about they just attach the thing to a parachute, mount it on a hatch, and if it catches fire...poof! Overboard it goes.   Frankly, just as sensible as evacuating an aircraft on the runway when there is no indication of fire or actual smoke, as ANA did. Hysteria much?

I disagree...ANA did the right thing. They'd just had a battery fire. Then, very soon after, they got a battery warning and a funny smell...evacuation was the prudent thing to do. Evacuation, although quite likely to cause minor injuries, is very unlikely to hurt anybody in a major way. There is almost no harm (and considerable potential benefit) to evacuating when you're not sure what's going on.

Quoting wjcandee (Reply 164): All aircraft have batteries. All batteries have the possibility of thermal runaway.

True. That's why the possibility was designed in. However, the FAA required a certain maximum probability of a fire. With a single data point (the Boston event) you get no data on probability so the FAA had nothing to go on. With the second event, you get frequency data, and it pointed in a direction that was certainly against what the FAA had requested. Hence the situation changed drastically after the second event.

Quoting wjcandee (Reply 164): The only thing that is sad to me is that, without any demonstrated effect on safety of flight, the plane has been grounded while the problem is being solved.

It's not about demonstrated effect on safety of flight, it's about demonstration of compliance with regulations. There are lots of ridiculous regulations that you still have to comply with, even if they have no direct bearing on safety of flight.

Quoting DocLightning (Reply 165): The only "mishandling," if any, was that it took the FAA until the next day to ground it.

I disagree. After the first event, nobody had any data on whether this was very bad luck or the start of something...you don't get any rate data off a single event. All that the first event did was show that something that was believed to be possible was possible. The second event provided rate date...that's what triggered the FAA, I suspect.

Quoting DocLightning (Reply 165): I will point out that the OEM also failed to detect these problems during testing.

That's only relevant if it's a design problem, and so far we don't know what it is. OEM testing can only pick up a manufacturing defect during testing if the defect is also present during the testing.

Quoting airtechy (Reply 170): I doubt they will learn anything from the two charred batteries.

You'd be surprised at how good aviation investigators are. They can learn incredible things from what appear to be useless lumps of charred rubble.

Tom.

Quoting WingedMigrator (Reply 172): Quoting CM (Reply 171): Boeing cannot legally comment on the battery issue beyond a set of statements which are entirely controlled by the NTSB. I cannot believe that even for a second. They might be strongly discouraged from commenting, and even further discouraged by the possibility of inadvertent self-incrimination, but legally barred? No such law on the books.

Well...time for the lawyer to do what lawyers do:

49 CFR 831.13

"§ 831.13
Flow and dissemination of accident or incident information.
(a) Release of information during the field investigation, particularly at the accident scene, shall be limited to factual developments, and shall be made only through the Board Member present at the accident scene, the representative of the Board's Office of Public Affairs, or the investigator-in-charge.
(b) All information concerning the accident or incident obtained by any person or organization participating in the investigation shall be passed to the IIC through appropriate channels before being provided to any individual outside the investigation. Parties to the investigation may relay to their respective organizations information necessary for purposes of prevention or remedial action. However, no information concerning the accident or incident may be released to any person not a party representative to the investigation (including non-party representative employees of the party organization) before initial release by the Safety Board without prior consultation and approval of the IIC."

There's other stuff out there along these lines. The point is that the NTSB is in control of the information flow.

That's why Boeing is gritting its teeth, and folks like Gordon Bethune are being rolled out to call the FAA morons for the grounding.

[Edited 2013-01-20 22:36:10]

Quoting CM (Reply 173):

But the FAA won't put words into Boeings mouth, i.e if Boeing don't say fire the FAA wont insert the word fire into Boeing communication so Doc's point still stands, De Nile is a river that runs through Chicago.

Quoting tdscanuck (Reply 174):

Seems like a reasonable summation

A couple of Questions for the Boeing guys:

Do the individual cells on the 787 battery have individual charging circuits?

What if any systems or capabilities does the 787 lose if it loses the main battery?

Quoting wjcandee (Reply 175):

Thanks for that. Also found additional (similar) rules for parties to an investigation here: http://www.ntsb.gov/doclib/forms/NTSB_Investigation_Party_Form.pdf which is effectively the contract the OEM signs when they are made a party to the investigation.

It appears it is a matter of legislation, as the document cites 49 C.F.R. §§ 831.11 and 831.13 as the authority for the policy.

Quoting BoeingVista (Reply 176): But the FAA won't put words into Boeings mouth, i.e if Boeing don't say fire the FAA wont insert the word fire into Boeing communication so Doc's point still stands, De Nile is a river that runs through Chicago.

It's the NTSB, and I suggest you go read the linked policy. It makes it clear the words which are made public or provided to the media - all of them - will come from the NTSB.

Quoting tdscanuck (Reply 174): you don't get any rate data off a single event.

Sure you do: you've had one event per N flight hours. You have a rate from that, albeit with a wide confidence interval. Two observations will give you a tighter confidence interval, three even more, etc.

Quoting wjcandee (Reply 175): 49 CFR 831.13

Thanks    and apologies to CM.

So I am wondering what sort of activity, if any, there is in the desert to put mothballed frames back in the air, to make up for lost 787 capacity? What sort of capacity pinch are the Japanese, especially, facing?

Also, does anyone remember what sort of capacity pinch happened when the DC-10 was grounded? Did airlines pull planes out of the desert?

Or did/will everyone just tough it out for the time being and lose customers if not enough seats are available?

Thanks

Quoting WingedMigrator (Reply 172): I cannot believe that even for a second. They might be strongly discouraged from commenting, and even further discouraged by the possibility of inadvertent self-incrimination, but legally barred? No such law on the books.

The actual rule is probably in the agreement that the non-NTSB parties have with the NTSB, but check out slide 12 of:

http://www.ncdot.gov/transcomm2012/about/IncidentManagmentNTSB.pdf

Probably a party would not face a criminal sanction violating the rule, just the contractual one, but will likely get bounced out of the investigation if they do. And just how long is the NTSB's investigation of the 787 going to take *without* Boeing's expertise?

Anybody who callas the FAA morons for that grounding is a moron. An in-flight fire which can not be put down by any means available on the plane is a huge risk. The battery failing is not a huge problem, the failure mode is. Just read up how long the fire department in Boston needed to kill the fire and how hard it is to kill such a battery fire, this is a big problem for an ETOPS180 or ETOPS 120 plane. The battery should not ignite and it should not spill its contents, which means that the containment also failed.

For me the FAA faces 3 facts.

1. those batteries fail (that is the easy one)
2. the failure mode is critical (by design), the designed counter measure fails as well (containment)
3. there is no other option available on the plane to put out a battery fire

Quoting CO953 (Reply 179): Also, does anyone remember what sort of capacity pinch happened when the DC-10 was grounded? Did airlines pull planes out of the desert?

United was still a dozen or so years from retiring their stretch DC-8s, which they could substitute on some of the DC-10 routes. One flew the morning outbound/evening return for SFO-IAD-SFO at the time as a sub.

Quoting WingedMigrator (Reply 178): Thanks and apologies to CM.

Thanks, but not at all necessary. I've learned from more of your posts over the years than I can count. We're all a bit smarter because of others here.

Quoting tdscanuck (Reply 163): How is this a fact? In both cases, the battery fire was contained and no other equipment was taken down in the process. Isn't that the containment requirement?

From the FAA original statement:

"The battery failures resulted in release of flammable electrolytes, heat damage, and smoke on two Model 787 airplanes. The root cause of these failures is currently under investigation. These conditions, if not corrected, could result in damage to critical systems and structures, and the potential for fire in the electrical compartment"

I see no argument here!

When you sign the form that CN linked to, you agree to abide the rules in the attached Guidance for Parties, which can be found at: http://www.nata.aero/data/files/ntsb_investigation_party_form.pdf The Guidance is annexed directly behind the form to be signed.

The relevant portion is as follows:

"VIII.
Release of Information
Prior to the NTSB’s adoption of the final report, only appropriate NTSB personnel are authorized to publicly disclose investigative findings, and, even then, the release shall be limited to verified factual information identified during the course of the investigation. In addition, party participants or their respective organizations must refrain from providing opinions or analysis of the accident outside of the participants in the investigation. Failure to abide by these requirements may lead to removal of a party from the investigation."

Also: from Section VII: "Limitations on parties commenting publicly on possible findings of the investigation, including the probable cause of the accident, will remain in effect until after the Board adopts the final report."

So its pretty clear that you let NTSB do the talking until the final report, in terms of characterizations and expected outcomes, or you can lose your party status.

http://www.ainonline.com/aviation-ne...battery-fires-keeping-li-ion-caged

One solution could be putting the batteries in similar bags and adding a Halon injection system that fills the bag in case of a runaway cell. It would probably also be an option to reduce the number of cells in each battery pack.

Quoting CM (Reply 177): It's the NTSB, and I suggest you go read the linked policy. It makes it clear the words which are made public or provided to the media - all of them - will come from the NTSB.

You know, no.

The linked document says the NTSB will be the only voice but Doc and myself were referring to the Boeing statement on the Boston incident http://boeing.mediaroom.com/index.php?s=43&item=2554 that failed to mention a fire and was clearly made by BOEING not the NTSB after the NTSB had begun the investigation... So I'm really not getting your point here at all...

Quoting CM (Reply 171): Doc, I get it that you do not like what Boeing has said (or has not said) in their public communications about the two battery fires. What you may not realize is that once the NTSB opens an investigation into any accident or incident, all public comments on the subject from the OEM are dictated by the NTSB. Boeing cannot legally comment on the battery issue beyond a set of statements which are entirely controlled by the NTSB.

So while the NTSB repeatedly used the term "fire" in their January 8th press release, Boeing was then told by the NTSB to call it a "787 event". Sorry, that's downright comical.

Quoting tdscanuck (Reply 163): So far, the existing events have demonstrated that the containment *does* work.

I guess this is why I seem to be repeating myself. According to the FAA, containment did not work. They say exactly why they think it didn't work. Smoke and flammable material were not contained, and posed a potential hazard to other aircraft systems. You could say that nothing was damaged by the "containment" that is being disputed, but the FAA feels it is not satisfactory in that it could have damaged important systems.

But the material did not cause damage to any other major system. How was that a failure of the containment?

Quoting KC135Hydraulics (Reply 190): But the material did not cause damage to any other major system. How was that a failure of the containment?

Because FAA believes that there is a chance that we won't get that lucky the next time. The words from FAA: "These conditions, if not corrected, could result in damage to critical systems and structures, and the potential for fire in the electrical compartment".

Quoting KC135Hydraulics (Reply 190): But the material did not cause damage to any other major system. How was that a failure of the containment?

I find your argument basically flawed. The fact that the material didn't actually cause damage to any other system doesn't mean that the containment didn't fail. The very fact that the material left the container means that it wasn't contained. Whether or not it did any damage - once not contained as it should have been - is an entirely different matter.

Quoting seahawk (Reply 181): An in-flight fire which can not be put down by any means available on the plane is a huge risk

But no such thing ever happened here

Quoting seahawk (Reply 181): Just read up how long the fire department in Boston needed to kill the fire and how hard it is to kill such a battery fire, this is a big problem for an ETOPS180 or ETOPS 120 plane.

For the actual fire-fighting on the ground, I suggest you read the posts by rcair1
But fire-fighting on the ground and containement in flight are 2 different problems, as has already been mentioned countless times on these threads. Sure, they are related, but you can't directly apply knowledge regarding one scenario to the other

Quoting seahawk (Reply 181): The battery should not ignite and it should not spill its contents, which means that the containment also failed

Not necessarily, if the contents spilled in a way which does not endanger critical systems then it worked. Which seems to be the case in these 2 incidents. However it seems that preliminary observations indicate that under additonnal specific circumstances, there is a possibility of critical damage. Such possibilities have to be rigorously ruled out before the planes can fly again.
But this does not mean that the system actually failed in Boston or in Japan

Quoting packsonflight (Reply 184): I see no argument here!

see above

Quoting FlyingAY (Reply 191): Because FAA believes that there is a chance that we won't get that lucky the next time.

Exactly ! But that does not mean the containement failed in the 2 actual incidents

Quoting BoeingVista (Reply 187): but Doc and myself were referring to the Boeing statement on the Boston incident http://boeing.mediaroom.com/index.php?s=43&item=2554 that failed to mention a fire and was clearly made by BOEING

That was a statement made a single day after the incident, and perhaps before the NTSB issued its own statement with preliminary findings. In which case no really reliable information was available - just check the first threads to see how much contradictory and incomplete info was going around. So I can't really blame Boeing for using a vague, generic term.
Basic rule : you do not act upon unreliable information.

And in any case, for that very reason, the only relevant technical information regarding these on-going issues is the information provided by the NTSB. I couldn't care less about what Boeing says in press statements

Quoting BLRAviation (Reply 3): If empty flights are allowed like in the case of AI, then by the same logic, test flights should also be allowed.

Ferry flights have an inbuilt procedure with appropriate permission from Regulatory.

Quoting airmagnac (Reply 193): Not necessarily, if the contents spilled in a way which does not endanger critical systems then it worked. Which seems to be the case in these 2 incidents. However it seems that preliminary observations indicate that under additonnal specific circumstances, there is a possibility of critical damage. Such possibilities have to be rigorously ruled out before the planes can fly again. But this does not mean that the system actually failed in Boston or in Japan

I am sorry. I simply do not understand what you write here.

I think it is a known fact that batteries do from time to time break down in a way as we have seen in Boston and Japan. So systems must be in place to handle such a situation safely. The two batteries are located in different places as far as I understand. Why they broke down is as of yet unknown reasons - perhaps it is only a matter of bad luck. A lot of systems can be put in place to avoid batteries breaking down very often. But they will from time to time as I understand the discussion so far.

Now the fact that a totally foreseeable event actually happens - something that everybody - including Boeing - know will happen now and again - should not ground the 787. Either something has happened that has not been foreseen or some (containment) system didn't work as intended. If everything just did work as planed the incident shouldn't have lead to a grounding but only a new battery.

Quoting airmagnac (Reply 193): contents spilled

If contents were spilled the containment has failed. To have spilled content, you don't need a containement.

Quoting airmagnac (Reply 193): But this does not mean that the system actually failed in Boston or in Japan

Wrong. The design failed spectacularly to stay within the bounds as layed out very profoundly by the regulatory requirements.

There is a lot of wordart in these threads to play down what happened. But wordart won't impress a fire that evolves hundreds from miles away from the next airstrip.

As if anybody would really be interested to learn how well the containement would prevent spilled content and held back smoke during a 40min on board fire over the Pacific. As if the luck would not have been stressed enough...

IMO what we know is enough to admit, that neither Boeing nor the FAA have prooved to build and certify solid airborne lipo-appplications. From what we know today they can't provide valid guarantees that the today solution works safely. Because the guarantee that they gave initially has been rendered obsolete.

A lot of the initial intentions and plans have become paper waste due to real world events...

Quoting airmagnac (Reply 193): For the actual fire-fighting on the ground, I suggest you read the posts by rcair1 But fire-fighting on the ground and containement in flight are 2 different problems, as has already been mentioned countless times on these threads. Sure, they are related, but you can't directly apply knowledge regarding one scenario to the other

I guess you mean rcair1´s post about the low energy stored in the battery or to be more exact you little Jet-A is needed for that amount of energy. But this is not the problem imho. A lipo battery that has reached a critical state will re-ignite again even if the fire is extiguished for a moment unless either all energy and flaming content is burned or you cut it from any oxygern supply or you cool the remaining cells down. And this means cooling down an unstable cell which might be undergoing a reaction which heats itself up. I see non on-board system that can do this.

Quoting rheinwaldner (Reply 196): If contents were spilled the containment has failed. To have spilled content, you don't need a containement.

There does seem to be a major disagreement here about something that I would intuitively have thought was very simple to agree on.

Quoting BoeingVista (Reply 176): Do the individual cells on the 787 battery have individual charging circuits?

No battery is going to have separate charging circuits for each cell, but they can have monitoring circuits for each cell. I'm gathering that Boeing didn't go that route from the reports so far, so it would take an autopsy to try and determine the sequence of events.
There are two ways a bad cell could cause overcharging and failure. A bad cell can not pass charging current as well, causing the voltage on that cell to go up and cause grief, or you can have a shorted cell, which causes the voltage on the other 7 cells to rise. "No more than 32 volts" doesn't tell you that there was no overcharging or excessive voltage.

Being old and inflexible, I'm thinking that they need to rely a little less on computer odds crunching and more on Murphy.

[Edited 2013-01-21 04:13:52]