Dreamliner: Boeing 787 Aircraft Battery "Not Faulty" 184
A reader writes "Airline safety inspectors have found no faults with the battery used on Boeing's 787 Dreamliner, Japan's transport ministry has said. The battery was initially considered the likely source of problems on 787s owned by two Japanese airlines. The world's entire fleet of 50 787s has been grounded while inspections are carried out. Attention has now shifted to the electrical system that monitors battery voltage, charging and temperature. Transport ministry official Shigeru Takano said 'we have found no major quality or technical problem' with the lithium-ion batteries. Shares in GS Yuasa, which makes the batteries, jumped 5% on the news. 'We are looking into affiliated parts makers,' he said. 'We are looking into possibilities.'"
Japanese covering their butts? (Score:5, Insightful)
Re:Japanese covering their butts? (Score:5, Insightful)
Re:Japanese covering their butts? (Score:5, Informative)
This [mpoweruk.com] is a nice quick review of Lithium nastiness....
Possibility (Score:2)
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One of the planes was about a year old, the other a couple weeks. The older plane had seen its Li-Ion batteries replaced in more recent times, and the two suspect batteries were within 30 serial numbers of each other. If they're wearing out *that* quickly I'd be worried.
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How many batteries are there in each aircraft? just one?
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Of this type? Two. The APU and the main battery. They are identical and thus interchangeable such that if the main battery is not charged or otherwise not functioning before a flight, you can swap the APU battery in its place. There are, IIRC, other batteries scattered throughout the plane. Unsure if they're Li-Ion or not.
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How do you start the engine to turn the alternator?
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I'm really surprised those 787's haven't been falling out of the skies by now.. As usual, (this goes for most electronic products built in the last 25 years or so.) someone along the line ignored some critical thermal management details..
Recharging Eight(8) 60+amp/hr LiCoO2 cathode based batteries packed neatly in rectangle configuration configuration at nearly 0.8C. (75 minutes.) is a receipt for inevitable failure. Yeah.. the battery is spec'd for 0.8C. charge rate.. But, not packed side by side oth
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Batteries will fail, usually in some sort of spectacular manner. Their specific chemistry doesn't matter. In fact this is so well known, and the possibility of a fire was so well anticipated that Boeing did indeed design a containment cage for these batteries. Take a look at the pictures from the Boston incident. The heat damage was pretty well contained (the containment vessel was damaged quite significantly, but the rest of the nearby electronics remained intact). What *wasn't* contained, and what li
Re:Japanese covering their butts? (Score:4, Funny)
Exactly. I am wondering how many months the planes that have this problem have been in service. Why didn't this overheating problem happened in the earlier months? Testing a new battery will not get you anywhere. Testing an aged one maybe.
You guys should work for Boeing, I bet they never thought about testing used batteries from a different aircraft, or testing other, non-failed, batteries from the problem aircraft.
When they said they ruled out the batteries, they probably just rang up the battery manufacturer and said "Hey, we need to test your batteries, send us a couple new ones. But make sure they are ordinary batteries off the production line, don't spend all night cherry picking the best ones".
Re:Japanese covering their butts? (Score:5, Interesting)
The cells do not have identical leakage, so some cells tend to overcharge to compensate for the other cell in the stack which leaked its charge away.
This phenomena shows up after the cells have been in service for months to years.
The older chemistries I have worked with have been relatively tolerant of overcharge, converting the excess energy either to heat or hydrogen gas, which was silently vented. Lithium ion cells are not nearly as tolerant to overcharge as NiCd, LiMH, or Lead-Acid cells. Overfilling a lithium ion cell seems like overfilling a propane tank. Once it tops off, there is nowhere for the excess energy to go and POP goes the weasel.
If you are charging based on stack voltage, you will overcharge the hell out of a good cell as you try to bring the terminal voltage of a weak cell up. You will detonate your good cell in the process.
I am currently playing around with a lithium battery pack monitor with which I have individual chargers for each cell. There is no way I would consider charging all cells in series as is commonly done in the earlier packs. With the DC isolation I can easily get from high frequency inverters, it is quite easy for me to get matched voltages from multiple windings. I use supplemental converters to additionally charge individual cells that leak a bit more than others in the pack. I also have switched cell monitors which rapidly switch each cell onto a measurement buss along with three tightly controlled reference voltage sources. This results in a signal stream which indicates terminal voltage of every cell in the pack, cell by cell. This feeds a digitizer which constantly tracks each cell voltage and is instructed to terminate battery function if any cell shows over or under charge. If a cell simply needs a little help, the individual cell inverters kick in to boost the weaker cell and such activity logged.
A supplemental benefit of the serial analog data stream is that I can use any oscilloscope to see all the cells at once... I can sync to cell 0 which is the reference voltage. ( three references because this is so critical that if I have a reference drift I will have two others that hopefully are providing reliable data. Bad data = explosion; false trip=expensive downtime ).
Lithium batteries have a lot to offer, but they are also quite a bit more volatile than other chemistries I have worked with. Even YouTube has quite an assortment of videos of overcharged lithium cells igniting. Like a propane tank, they are quite useful if not mistreated, but can really take you to the cleaners if you do.
Re:Japanese covering their butts? (Score:5, Insightful)
As opposed to the American company that is heavily supported by the American government telling us the fault must lie with the Japanese batteries it bought. I see where you are coming from.
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Unlikely. The main battery faults of the past in this type of battery are metal shavings (Sony, e.g.) and problems with the insulation. Both are easy to identify once you know what you are looking for. The battery controller is a different matter: Highly complex software, possibly outsourced to some 2nd world country where they did not really understand what they are doing. I predict this is another instance of sub-standard software engineering practices that are so common in the industry today.
Which way will it go? (Score:5, Interesting)
The 787 is a revolutionary aircraft on many levels, from features to construction technology to production methods. I would expect there to be unforseen issues resulting from interaction between different systems. What I'm curious about is whether Boeing will get them all sorted out quickly enough...in which case they will be superbly positioned to compete, having mastered the many challenges around making the 787 what it is. If they don't, then they will be in terrible trouble. I feel like I'm watching aeronautical history playing out before my eyes.
I hope they get it all fixed in time, personally. The 787 is a hell of a plane. Check it out here: http://www.newairplane.com/787/ [newairplane.com]
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Do you work for Boeing or something...?
Re:Which way will it go? (Score:4, Insightful)
The 787 is a revolutionary aircraft on many levels, from features to construction technology to production methods. I would expect there to be unforseen issues resulting from interaction between different systems. What I'm curious about is whether Boeing will get them all sorted out quickly enough...in which case they will be superbly positioned to compete, having mastered the many challenges around making the 787 what it is. If they don't, then they will be in terrible trouble. I feel like I'm watching aeronautical history playing out before my eyes.
I hope they get it all fixed in time, personally. The 787 is a hell of a plane. Check it out here: http://www.newairplane.com/787/ [newairplane.com]
I'm not surprised by unforseen issues from the new technology and design (like the fuel leaks that have been reported), I'm quite surprised to see battery problems since they must have already run the batteries and charging system through many thousands of simulated takeoff/landing cycles both in bench tests and while installed in a test airframe.
Re:Which way will it go? (Score:5, Interesting)
I'm not surprised by unforseen issues from the new technology and design (like the fuel leaks that have been reported), I'm quite surprised to see battery problems since they must have already run the batteries and charging system through many thousands of simulated takeoff/landing cycles both in bench tests and while installed in a test airframe.
This. They knew the batteries were problematic. The Boeing engineers and subcontractors aren't idiots. Even if the snarky NYT opinion piece which suggests that Japanese firms were preferentially picked for financial rather than technical reasons is true - those said Japanese firms aren't exactly slouches (GL-Yeasu (sp?) makes Lithium ion batteries for spacecraft.
Sounds like a production issue. But these things are complicated. Look at the F22. That's why it's called the bleeding edge.
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Bleeding edge is for military aircraft, not commercial airliners that carry hundreds of people at a time with as little downtime as possible.
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Bleeding edge is for military aircraft, not commercial airliners that carry hundreds of people at a time with as little downtime as possible.
Some aircraft needs to make the leap to new technology or airliners would still be using unsealed lead-acid batteries.
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Wouldn't be the first time that testing has failed to represent actual use though. Even Boeing's flight testing may no be representative of how an actual airline operates the plane.
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" Attention has now shifted..."
You would think that given the importance of finding the problem here, they would have teams working in parallel looking at all the possible causes. They probably do, but the reporters just don't understand.
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I was more excited about the A380 myself, but I realize that there's a very small market for such large planes.
The 787 is using a lot of unproven tech. "Revolutionary" is good when it's built on sound fundamentals. I'm not sure the 787 was built this way. Rather, I suspect it was built on barely-good-enough and laboratory-tested, which are not encouraging signs.
There's a reason why a lot of civilian technology comes out of military research. Using it in the military will test the technology in the real worl
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Maybe lithium-ion batteries have been, too; I don't know. But IMHO considering how many millions of lithium-ion batteries are in service around the world, and in how many different applications, this can't be such a fundamental flaw. I think more likely a bug.
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And the military can compensate for greater risk of partial or full failure, both by the operators' prior training and greater built in redundancy as a result of a higher price tag that only the military would pay.
And by a tolerance for (or apathy towards, po-tah-to) loss of life in regards to compensatory damages.
In recent years, though, families have begun to sue manufacturers of military craft (e.g. Sikorsky) for wrongful death, so maybe this dynamic will change.
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I was more excited about the A380 myself, but I realize that there's a very small market for such large planes.
Forgive me, but is that true? I live in NZ and most planes to/from here are 747s of some colour. Those planes have been the backbone of international fleets for decades (the sixties?). I would say that there's a huge market for long-haul big planes - world population is going up, countries aren't getting any closer. The world's fleet of 747s will eventually need replacing with more 747s, or 380s, or ... something of that size. But now the long-haul runs need to be fuel-efficient and cheap.
And safe
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+1. The 787 is technically nice of course, but it's not really exciting the same way that a plane half again as big as the next smaller one.
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Another NZer here.
The difference in approach is that Airbus bet the farm on big planes travelling between hubs, then small (A320 sized) planes taking people to their final destination.
Boeing has bet the farm on smaller long range planes taking people exactly where they want to go.
It's going to be interesting if one of them has hit the winning formula, or if there's enough competition and different habits to support both approaches.
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I was more excited about the A380 myself, but I realize that there's a very small market for such large planes.
Excited? About something slightly bigger than the 4-decade-old 747? The most interesting thing about that plane is the prospects for sales to recoup even a significant fraction of the tens of billions the European companies, err, countries , paid to build it. Forget about bailing out Greece, Portugal, et al., some of those Euros are going straight into subsidies to the companies assembling it. Financially interesting, technically not so much.
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"I would rather you just said thank you, and went on your way, Otherwise, I suggest you pick up a weapon, and stand a post." Memorably delivered by Jack Nicholson as Col. Jessup in "A Few Good Men" (http://www.imdb.com/title/tt0104257/quotes)
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An A380 can fit 800 people. The newest, extra long 747-8 can't even hold 500.
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Wow, that's over 50% bigger! I'm just saying it's (obviously) not as technically interesting as employing an entirely new building material and process. And the 380's size is wonderful, until you are waiting for your bags or for customs with another 300 fellow passengers. Boeing decided that more efficient was better than bigger. And without governments to write-off the initial investment, a bigger plane would never pay off. It still might not be truly profitable, ever, anyway. Governments are also inv
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What I'm curious about is whether Boeing will get them all sorted out quickly enough...in which case they will be superbly positioned to compete, having mastered the many challenges around making the 787 what it is.
You will find that Murphy has a big bucket of bugs to keep dishing out from for the Dreamliner and Boeing.
IMHO This is a product jinxed by management hubris.
I hope they get it all fixed in time, personally. The 787 is a hell of a plane. Check it out here: http://www.newairplane.com/787/ [newairplane.com]
PR drivel, the only vector of exellence for Boeing these days.
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You are.
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yes!.
capability of fixing problems.
Though I would rate the ability to nix design problems before they endanger customers significantly higher.
Every oaf can do colorfull leaflets and produce problems while offshoring all responsibility.
more conventional batteries add few hundred lbs (Score:5, Interesting)
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At this point, since it;'s not the batteries themselves, it's most likely the charging system that's faulty. Li-Ion batteries have a more extreme reaction to overcharging, but it's not like lead-acid batteries wouldn't have problems.
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They actually had similar problems with NiCad when they first put them in planes. The failure modes for NiCad are not as bad. NiCad doesn't create a self-sustaining fire the way Li-ion can, but overheated NiCads can (and have) caused nearby objects to melt and/or catch on fire.
If it is the electronics, then it's possible that even if they'd gone with NiCad, they could still be having problems with the battery subsystem. The only difference in that case would be that you wouldn't have the "why did those i
Re:more conventional batteries add few hundred lbs (Score:5, Informative)
On single cells, that protection is a small IC affixed to one end of the battery. In a battery pack, there is a protection circuit that covers the entire pack. For a battery bank, it's perfectly reasonable to combine the protection circuit with the charging system. In consumer goods where the battery isn't a user replaceable item, the protection is built in to the charging circuit. In any of those cases, a defect in the protection circuit can lead to a problem.
In all of the above cases, the protection includes preventing over charge and over discharge (fatal to LiIon batteries).
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Yes, in the Boeing case, there must be a design flaw somewhere. Some set of conditions that didn't exist when they tested the things must be able to cause an overcharge without tripping the protection or causing an alert.
It could even be that the system as designed works fine until vibration breaks something.
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Of course it has over-charge protection. Most likely that protection is exactly what went wrong. It's not like they can just put a mechanical switch in there like a circuit breaker. It's all chips nowadays, you know.
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Most clueless posting so far. Of course batteries and charger are a unit.
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*sigh* We've been through this before - yes, the total saved is small per flight. But multiply it out across the decades the plane will be in service and it adds up to a very substantial sum. To folks who have to actually pay the bills, this matters. Hell, to anyone with a basic understanding of accounting (rather than
A Bit of a Deceptive Statement (Score:4, Interesting)
Driving into work this morning, I heard this same quote on NPR:
"Airline safety inspectors have found no faults with the battery used on Boeing's 787 Dreamliner, Japan's transport ministry has said."
Worded as such, I think most people would get the wrong impression. They're defining the battery as if it's sitting in someone's pocket, detached from any relevant system & unable to charge or discharge; I didn't think of it that way, and I'd suspect most others didn't either. Most news outlets could use the clarity (albeit, only eventually) provided by the BBC article. The battery *itself* is not the culprit, but investigators essentially *do* still suspect the battery *system,* including the batteries themselves.
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U
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I disagree. I think most people think of the battery as only the lump of chemicals that stores the charge. Most people would not think of all the electronics as being part of the battery.
Not entirely surprising (Score:5, Insightful)
Not entirely surprising, its usually the charger and/or the discharge protection ckts. Ask the RC electric airplane people who have at least a decade or so experience with lithium batteries in airplanes and burning them up. I was into RC planes back when everyone used NiCad but I've kept up with recent events. The batteries themselves rarely burst into flame, they burst into flame when you connect them to something that does something very naughty well outside the limits of the datasheet.
I think this will probably, in the long run, turn into a "EE ethics and morals class" debate. So discharging 15 amps out of a 10 amp pack results in a 0.001% chance (actually pretty high) of blowing the pack up per the data sheet. However not supplying 15 amps to the engine control system during an alternator malfunction (or whatever) means the engine shuts down and 500 people have a near 100% chance of death. "just follow that datasheet" stuff could kill lots of people, then again "ignore the datasheet" could kill lots of people too. So if you must use lithium batteries (why?), then you can find a local minimum death rate which will not be zero... of course finding that might have to be done via experiment on unwilling crash victims, whole nother ethical issue. Basically, we're trading human life for slightly improved gas mileage, which certainly makes me want to fly on a carrier using airbus products instead of boeing products, which has other ethical issues, etc. Is the ethical/moral failure the managers for doing it despite advice against, the engineers fault for not committing career and economic suicide by refusing to design a lithium aircraft pack, the supplier for making batteries for an unsuitable purpose, the arabs fault for making jet fuel so expensive so we have to kill people with lightweight batteries, ...
The simplest thing is a battery drop tank arrangement or a rather stout thick wall steel case, making the works heavier than using old fashioned lead acid.
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So discharging 15 amps out of a 10 amp pack results in a 0.001% chance (actually pretty high) of blowing the pack up per the data sheet. However not supplying 15 amps to the engine control system during an alternator malfunction (or whatever) means the engine shuts down and 500 people have a near 100% chance of death.
So what you're really saying is "Take the number of [batteries] in the field, A, multiply by the probable rate of failure, B, multiply by the average out-of-court settlement, C. A times B times C equals X. If X is less than the cost of a recall, we don't do one. "
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That’s what the bean counters call a simple actuarial analysis.
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There's also some net present value calcs of taking to profit today vs paying the settlements years later, but yeah.
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No, you want to still be employed. That way they have to give you a golden parachute when they fire you.
Nuanced response (Score:5, Informative)
So what you're really saying is "Take the number of [batteries] in the field, A, multiply by the probable rate of failure, B, multiply by the average out-of-court settlement, C. A times B times C equals X. If X is less than the cost of a recall, we don't do one. "
The actual answer is more nuanced.
FAA regulations define 5 levels of critical for safety systems: levels A through E.
Level A is for things that can knock a plane out of the sky when they fail; for example the stall speed alarm.
Level C is for things that can cause injury or at most a single death; for example, the cabin pressurization system
Level E is for things that don't affect flight safety; such as, in-flight entertainment or the microwave in the galley
For reference, I wrote the software for cabin pressurization systems. It's level C (hardware == B), which means that failure in pressurization is an emergency situation, but isn't expected to kill everyone on board. The masks drop and the pilot immediately dives to under 10,000 feet to restore breathable air.
If the cabin fills with smoke, it's not life-threatening per se. The pilot can override the pressurization system and "dump" the cabin atmosphere, and it clears pretty quick. (The captain also dives to under 10,000 feet if necessary.)
The battery catching fire isn't a problem SO LONG AS the fire itself won't cripple the aircraft. The battery underpowering the plane when the alternator dies MAY BE a problem which would kill people.
The people who design these things take these levels into consideration, and the general rule is "fail safe". If you can't "fail safe", then "fail in the least dangerous way". In my experience, the engineer must make many choices when designing an aircraft unit. The answer is always "do it *this* way, because if *that* happens it will be less dangerous.
Let's wait and see what the investigation uncovers. Here are some Cliff notes:
1) Li-Ion batteries might behave differently at altitude (cabin pressure is reduced while flying)
2) The battery may be performing to spec, while trying to compensate for a more dangerous problem
3) Smoke in the cabin is not as dangerous as you might think
4) Things that burn are designed to not damage things when burning
5) People who design aircraft are pretty smart, and have a generally high moral standard.
6) People who investigate aircraft incidents are really, really thorough, and have a good track record.
(Note: Glossing over some details to make an easier read.)
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The former is critical, the latter isn't an issue.
The fire can be contained, but it's the lithium that's a problem because it accellerates oxidation of aluminum. It's why there are regulations in place on transport of lithium in aircraft because a tiny bit of lithium can easily eat through critical aircraft stru
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There's a lot less aluminum in the largely carbon fiber 787. Doesn't this change the risk analysis?
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he said, "The actual answer is more nuanced. [gigantic detailed examples of possible outcomes].."
Sheesh. Doesn't *anyone* get the cultural reference I was quoting?
Screw it; I'm off to make some soap from human fat.
Tyler Durden (Score:2)
FWIW, I did get the reference (and I own the movie).
I was addressing the intent of the reference in its original context. There's lots of reason to despair the heartless actuarial calculations of corporations, but only where warranted.
Note that I didn't snark your post (an urge that I find difficult to control). Don't be disheartened - your post wasn't modded "Funny", even though it's a valid attempt. I was just trying to supply some background.
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Each engine and the APU in the tail have two generators attached, plus there is the RAT for emergencies. By all accounts the batteries are more or less there for consistency between power phases. The APU is supposed to be running during ETOPS segments, so one has to wonder what the power drain on the packs was to begin with. You would think the likely time for an accident would be on the taxiway while stuck for a long departure wait. I could see some engine stop and starts happening that might create the
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If you think Airbus isn't doing the same thing, you're deluding yourself. Minimizing the fixed weight load is the name of the game in aircraft design, and has been for a very long time. (Ford, Mercedes-Benz, General Foods, and pretty much every other company too... You want cheap flights, cheap cars, and cheap breakfast cereal, you're go
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Electrical Relay's (Score:2)
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Seems likely that you could be on the right track. I wonder if this has less to do with in flight conditions and more to do with APU and Ground power transitions because all the noted events took place close to either takeoff or landing and not in the middle of a long flight. I wonder about ambient temperature changes might be a factor too.
I can see where the transition to/from in flight and ground operations could be a lot more problematic for batteries and charging circuits due to momentary interruptions
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No problem with the battery (Score:2)
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Sum of the parts? (Score:2)
we have found no major quality or technical problem' with the lithium-ion batteries
How about several (many?) minor issues that, when taken together, add up to "the problem"? Also, since at least, one of the batteries was fried almost beyond recognition (from a photo I saw), how do you know there was no problem?
Overheating (Score:2)
Logs indicate no overcharging (Score:5, Interesting)
The battery charging voltages and currents are logged, the logs go to the flight recorder, and they don't indicate overcharging. [aero-news.net] There are monitoring circuit boards in the battery case, separate from the charger, which report this data. Either the charger failed in some way that caused an overcharge without the voltage sensing detecting this, or the battery itself failed.
The NTSB says they haven't found anything defective yet. The burned battery is enough of a mess that it's hard to extract much info, but they're using spectroscopy to check that the composition of the components was correct.
The grounding is necessary. The JAL aircraft at Logan only had 22 takeoff/landing cycles on it, and this has now happened twice, so the odds of further trouble are high. Over the next few days and weeks, batteries and chargers will probably be pulled from other aircraft and cycled through pressure chambers, shake tables, and hot/cold cycles in attempts to induce the failure.
Meanwhile, I suspect that there are frantic efforts at Boeing to design a replacement that doesn't use lithium-ion batteries.
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Dumb design. The enclosure looks positively american.
I've never seen something so superficially designed from japanese engineers.
Thales is French [wikipedia.org].
Brakes and wiring (Score:4, Interesting)
You can take it for what it's worth but the wide array of problems plaguing this plane right now, the wire harness does make sense. Though bad design or bad manufactoring is yet to be seen.
ROHS? (Score:2)
Interesting tidbit (Score:2)
"The airplane's control, navigation, and communication systems are networked with the passenger cabin's in-flight internet systems.[199] In January 2008, FAA concerns were reported regarding possible intentional or unintentional passenger access to the 787's computer networks. In response, Boeing stated various airplane protective
BP revisited (Score:2)
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oh definitely, let's all boycott planes made by "corporate fucks" and commit to flying only on planes made by little, friendly, ma-and-pa type ventures.
It was never the battery (Score:2)
It was never the battery that was the problem. Now, maybe the charging system of the battery, that's a different story. But the batteries themselves were not really though to be problematic. Most lithium ion batteries will become damaged if overcharged and overheat, even much later than the original overcharging. That is technically not a problem with the battery anymore than holding a lit match to a piece of paper is a problem with the paper (unless of course the design spec says it's not supposed to happe
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Exactly. The battery might be fine, but if other things in the system can make it catch fire, its not much consolation that the fault wasn't in the battery. It still might be a bad idea to put Li-ion batteries on aeroplanes.
Working as Designed (Score:2)
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Funny, but it's unlikely to be much of a contributor to a fire in a Lithium-Ion battery.
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On the contrary - lithium interacts very much with oxygen, and if oxygen did enter the battery cells due to pressure changes then it may still be the culprit.
And pressure changes are normal on an aircraft - especially at take-off and landing.
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Lithium Ion batteries supply their own oxygen. They don't burn with the air which makes them impossible to put out.
Re:Oxygen is usually the culprit in most fires (Score:5, Informative)
Actually it would not help. The nasty thing about these battery fires is the battery chemistry SUPPLIES OXYGEN.
Re:Oxygen is usually the culprit in most fires (Score:4, Interesting)
OMG, so THAT'S what Uncle Sam meant when he trained me to fight Class Delta fires!! Well, just push the damned thing overboard, and let the giant squids at the bottom of the sea worry about the fire!
Which reminds me - I saw a video one time - wonder if I can find it again . . . .
Can't find that particular video now, but this one gives you the idea:
http://www.youtube.com/watch?v=95O-bQo04Ok [youtube.com]
A fire department arrived at the scene of a cargo fire on board a tractor trailer. They proceeded to hose the fire down, and before they were done, a dozen other trailers had caught on fire. The fire would burn merrily along, the firemen would turn a hose on it, it exploded, they ran, and when the flames started to die down some, they would repeat. I wanted to laugh - but I've stood to close to the fire to many times to laugh, I kept expecting the fools to kill themselves.
Re:Oxygen is usually the culprit in most fires (Score:5, Insightful)
Water doesn't always work (Score:2)
My first day on the job in a very brief career as a firefighter, we responded to a vehicle fire. I backed up the engineer on the hose. The engineer pointed out the magnesium shifter in the cab of the truck - it was throwing sparks as if we were applying a grinder to it rather than 100gpm. Because it was small we could disapate enough heat to put out the fire, but it was kinda cool. We got more of an explanation back at the station.
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They tried that method of fire suppression. Then some idiots mislabeled canisters containing an oxygen generator and then they found their way into the cargo area of a passenger airplane. When the oxygen generators activates mid flight they provided both the ignition source and oxygen defeating the type of fire suppression system that you are suggesting. And thus it is no longer allowed.
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Consider the fact that batteries are experiencing pressure changes, vibration, temperature changes in addition to being charged/discharged and the fact that lithium interacts aggressively with oxygen and water as well I would say that the choice of that battery type is risky.
Pressure changes may cause oxygen to penetrate the batteries and make them fail.
That leads to the fact that the OP may be more right than funny.
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Media should learn when to shut up. Or people should think a bit more.
The process of Diagnosing a 787 isn't easy, a lot of parts, you first check the most likely causes and go further. The media love to jump and post the first guess from the engineers and scientists (a new study (That is in process, and hasn't been proven or peer reviewed) to show x = y, so it is written to make us think x = y), things like this just makes the common folk fear Ethnology and Science because it makes us sound like a bumblin
Osama Blue Laden (Score:3, Funny)
It would stop terrorism also: what a bargain!
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No need to suck.
Oblig That's what she said.
Why stop at oxygen? FAA Considering Passenger Ban | The Onion - America's Finest News Source [theonion.com]
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Sure the sudden increase in low air pressure might put out an onboard fire, along with a few of the passengers inside.
Here's a reference from appropriately-named ALOHA airlines: http://www.time.com/time/magazine/article/0,9171,149181,00.html [time.com]
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Not quite. The battery controller in the Boston fire specced out OK. That's useful but there are hundreds of other bits of electronics connected to the battery and the controller (something controls the controller). It probably isn't going to be a simple case of one thing out of spec - those would be picked up in the pre delivery checks. It's likely something that requires an interaction between a couple (or many) devices to create an edge case that no one has figured out.
Of course, you're going to wor
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It did. Not because the carpet was actually at fault, but it's less costly to recall a bazillion floor mats than to tell the customers a truth they don't want to hear: that the crashes were mostly the fault of panicked drivers frantically stomping on the accelerator.
Japan: still the undisputed world champions at face-saving.
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then the blame lies with the designers who used it: Boeing,
Boeing hasn't designed any subsystems stuff for years. I'm not even certain they have any structural people left.
Boeing produces a specification and puts it out for bid. The spec probably says: 'The battery shall not burst into flames or explode.' The implementation details are left up to subcontractors.