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FAA Grounds 787 Part 6  
User currently offlineNZ1 From New Zealand, joined May 2004, 2237 posts, RR: 26
Posted (1 year 2 months 3 weeks ago) and read 35144 times:
AIRLINERS.NET CREW
FORUM MODERATOR

Please carry on discussion here.

Previous thread located here: FAA Grounds 787 Part 5 (by iowaman Jan 23 2013 in Civil Aviation)#1

NZ1
Forum Moderator

291 replies: All unread, showing first 25:
 
User currently offlineRottenRay From United States of America, joined Jun 2010, 273 posts, RR: 0
Reply 1, posted (1 year 2 months 2 weeks 6 days 23 hours ago) and read 35146 times:

DocLighting writes:
" If there is, say, severe turbulence, it could navigate around the compartment that way."

Doc, you've taken blood samples - they're thinner than the electrolyte goo you're talking about. This stuff is not magically sticky in a picture and later capable of gymnastics in turbulence.

Also, just how turbulent are you talking about?

I don't see ANY liquid which is already stuck to something changing its direction in a major way with, say, a 2g event. I suspect that we'd have other issues to worry about at that point.

And, frankly, positing a battery meltdown followed by severe turbulence is something best left to Hollywood.

Really and truly, these situations just don't line up like that. Outside of Hollywood, that is.

Cheers!


User currently offlineliftsifter From United States of America, joined Feb 2008, 295 posts, RR: 0
Reply 2, posted (1 year 2 months 2 weeks 6 days 23 hours ago) and read 35144 times:

Has John Leahy made a comment at all about the grounding and how it may affect the A350 program?


A300 A310 A319 A320 A321 A332 A333 A342 A343 A346 A380 B738 B744 B763 B772 B77W B787 Q400 E190
User currently offlinesankaps From United States of America, joined Jan 2008, 2252 posts, RR: 2
Reply 3, posted (1 year 2 months 2 weeks 6 days 20 hours ago) and read 34587 times:

Some of the comments in the previous thread before it was locked are unbelievable!

"When has the FAA or NTSB ever been proactive?"

Well -- they are being proactive right now! Grounding the battery system and thereby the aircraft until they can be sure the root cause issues are identified and fied, before something disastrous occurs.

"It is all just politics".

In other words, Obama is to blame. Right. Boeing is based primarily in two states which helped Obama get re-elected -- Washington and Illinois. But Obama wants to screw them?

Guys -- we need to take a step back, read the NTSB statement, and just calm down and accept that the grounding wasa prudent, proactive step given the two incidents just 9 days apart, involving a new system and technology that had only recently been certified but hadn't really stood the test of time and extensive usage yet. That is exactly the right thing they did. And I love Boeing and its products as much as anyone else.


User currently offlineBraybuddy From Ireland, joined Aug 2004, 5572 posts, RR: 32
Reply 4, posted (1 year 2 months 2 weeks 6 days 20 hours ago) and read 34501 times:

Quoting RottenRay (Reply 1):
And, frankly, positing a battery meltdown followed by severe turbulence is something best left to Hollywood.

Murphy's Law. And aviation probably supplies one of the best (or worst) examples of same with the KLM/Pan Am collision at Tenerife in 1977: a bomb had exploded earlier at Las Palmas and the aircraft were diverted to Tenerife. Then you had the fog, the absence of ground radar, the misheard ATC instructions and the blocked-off taxiway. Had one of those events not occurred there would have been no collision.


User currently offlineUnflug From Germany, joined Jan 2012, 392 posts, RR: 2
Reply 5, posted (1 year 2 months 2 weeks 6 days 20 hours ago) and read 34482 times:

Quoting RottenRay (Reply 1):
Really and truly, these situations just don't line up like that. Outside of Hollywood, that is.

Unfortunately reality offers sometimes more phantasy than hollywood. Take almost any air crash investigation and you will find situations have lined up in ways not to be expected...


User currently offlineDocLightning From United States of America, joined Nov 2005, 18676 posts, RR: 58
Reply 6, posted (1 year 2 months 2 weeks 6 days 19 hours ago) and read 34433 times:

Quoting RottenRay (Reply 1):
Doc, you've taken blood samples - they're thinner than the electrolyte goo you're talking about. This stuff is not magically sticky in a picture and later capable of gymnastics in turbulence.

Do you know the consistency of this material over all temperature ranges? If so, how do you know? Also, blood is not terribly viscous and it gets all over everything. Are you saying this stuff is like blood?

Quoting Braybuddy (Reply 4):
Murphy's Law. And aviation probably supplies one of the best (or worst) examples of same with the KLM/Pan Am collision at Tenerife in 1977: a bomb had exploded earlier at Las Palmas and the aircraft were diverted to Tenerife

Yup. Just about every major aviation disaster in history has occurred because of an unlikely chain of events all coinciding (leaving aside intentional sabotage).

Quoting liftsifter (Reply 2):
Has John Leahy made a comment at all about the grounding and how it may affect the A350 program?

Even Mr. Leahy is smart enough to know to keep his mouth shut.

Anyway, it is far too early in the investigation to determine whether Airbus will actually need to make changes to the design of the A350, but you can rest assured that some people at TLS are watching these proceedings with great interest. And you can rest assured that none of them are gloating about it, because they know that if they are not careful, their new A350 might be next.


User currently offlineAirlineCritic From Finland, joined Mar 2009, 679 posts, RR: 1
Reply 7, posted (1 year 2 months 2 weeks 6 days 19 hours ago) and read 34312 times:

First, I'd like to thank once again CM, tdscanuck, rcair1 and others for informative posts. I would also like to welcome b2319 to a.net, your post certainly got me thinking about containment and relief valves as far more complex beasts than I had thought before. Thanks.

Second, I have a plea that this thread would not descent into political speculation or accusing NSTB or FAA of misbehaviour. They are one of the most respected organizations in the world in this area, and it would be, IMO, unthinkable that they would be misbehaving any way. They are the true experts. They have all the information that we do not have here in a.net. Exact state of containment systems and other equipment in the bays, for instance. If they say they need to ground the plane, they have a reason to do so. Even if it is just not being certain that no other damage occurs in some (perhaps obscure) other scenario than the one played out in the two incidents. Let them do their work.

And now to the topic of my post. I'm trying to understand different scenarios for lifting the grounding.

Scenario 1: Operational changes

ETOPS limitations, in-the-ground inspections, lower thresholds for diversion, perhaps some battery usage/charging changes in flight. If these procedures would be sufficient, the grounding could have been over in days. I can only conclude that either these procedures are insufficient, or that the NTSB does not understand the events well enough to allow the grounding to be lifted yet. Obviously, the root causes need to be found.

Scenario 2: Battery manufacturing quality

A problem is discovered in battery batches and/or manufacturing process, the issue is fixed and the planes start to fly again. If this was the solution, we could see the end of the grounding in weeks, particularly if defective batteries can be found by testing.

I think this is somewhat unlikely as the only fix, as I suspect the NTSB wants to understand how well the containment works in the eventual cases that even with high-quality batteries, there can be a thermal runway in one of them some day.

Scenario 3: Battery charging systems

Or perhaps these systems misbehaved in some way. A fix to them would be an engineering (and re-certification) process. In the best case this would take a few months, in the worst case more. I remember that the battery system manufacturer took seven years to design the current batteries. In my opinion, that is a very long time, and changing a component should be possible in months.

Charging system issues is a possible root cause, but it is looking a bit unlikely perhaps, if the early reports are true that the batteries were not overcharged. That being said, if the per-cell history of events burned down with the batteries, how would we know?

Scenario 4: Containment structures

It is probably not sufficient to fix the containment structures, but if a battery manufacturing fault is found, fixed, and the containment is enhanced to make the NTSB/FAA confident that it works in all cases, then the plane cloud clearly fly.

It is difficult to estimate how long this would take. A steel plate "shower curtain" would be very easy to add. Certification, analysis that it works in all cases would probably take longer. I'd say months.

A more significant modification, such as fluid venting out of the aircraft or even enlarging or moving the battery containment structure could take much longer. Half a year for venting out, years for moving the structure or making the EE bay larger to fit the new containment structure. FWIW, I think the shower curtain is probably going to be sufficient.

Scenario 5: Electrical system

Or maybe there is some issue with the electrical system that is causing trouble for the batteries. If this is the case, it would be very difficult and time-consuming to understand and fix the issues. But as an engineer, I find it difficult to believe this to be the case. Surely the design has voltage and current regulators that isolate the quality of the aircraft electricity from the quality of the electricity fed to the batteries.

But if they need to do something with the electrical system, it could take years. Adding a more high-quality regulation circuitry could be easy, however, maybe only months.

Conclusions

I think the issues are somewhere in categories 2 through 4. If a battery or charging system fault can be identified and a slightly enhanced containment put into place, the plane should fly in 4-6 months, if not sooner, at least as a temporary measure for current frames. And a more intelligent new containment adopted for future frames.

But it is also possible that once the events are understood, the current containment system is deemed adequate (as tdscanuck and CM believed early on in this thread). Then the critical time factor is understanding why the batteries failed, and I'd predict that to take some number of months anyway.

In the other extreme, it is also possible that the containment system needs a significant change. If no intermediate solution can be found, this could drag on for over a year. (Interestingly, according to Wikipedia, A350 should enter service mid 2014. If the worst comes to worst, we could see the 350 fly commercially before the 787 is back in the air. But I do not believe this to happen.)

Finally, I should add that none of this is rocket science. Batteries and charging systems are well understood. And the energy levels for containment are still... small, when you consider the size and energy content of the device. It is some number of times bigger than a car battery, not a nuclear bomb. Boeing engineers know how to enhance it, if it needs enhancing.

[Edited 2013-01-27 01:03:37]

User currently offlinesweair From Sweden, joined Nov 2011, 1804 posts, RR: 0
Reply 8, posted (1 year 2 months 2 weeks 6 days 18 hours ago) and read 34189 times:

Just maybe we will have to accept that lion batteries will catch fire, on any airplane that uses them. It will be up to the containment to be able to handle any fire. Or just ban the use of lion in air craft all together. Someone needs to develop a JET-A fueled fuel cell quickly..

User currently offlineseahawk From Germany, joined May 2005, 576 posts, RR: 0
Reply 9, posted (1 year 2 months 2 weeks 6 days 15 hours ago) and read 32780 times:

Looking at the Tesla Roadster electric car for example, I find it interesting that the individual cells are so small in their design, yet they still use an active cooling and heating system to control the individual battery packs. Even the space between each cell seems much larger in relation to the cell size, than in the Boeing solution:

I know it is a little of topic but interesting: http://www.teslamotorsclub.com/showt...hp/3810-Roadster-battery-%28ESS%29


User currently offlineCALTECH From Poland, joined May 2007, 2004 posts, RR: 27
Reply 10, posted (1 year 2 months 2 weeks 6 days 13 hours ago) and read 31835 times:

Quoting B2319 (Reply 260):

I joined a.net because, in part 3 of this thread, someone said the electrolyte "wasn't a liquid, it was a paste". What an absolutely ill-informed post if there ever was one. Anyway, the physical properties of the material to be vented will play a vital part of the safe handling of the release. Some examples of physical properties are density, viscosity, possibly solids content and so on.

How totally incorrect and ill informed the above post is. With out revealing too much information, the paste statement was relayed to us by the manufacturers, you can figure that out for yourself if you'd like, not just a statement put out there by a anet member. But if someone knows more than Boeing and Thales, be my guest, go ahead and post your information. This is why folks are bailing on this thread.



UNITED We Stand
User currently offlineb2319 From China, joined Jan 2013, 145 posts, RR: 0
Reply 11, posted (1 year 2 months 2 weeks 6 days 13 hours ago) and read 31536 times:

Quoting CALTECH (Reply 11):
How totally incorrect and ill informed the above post is. With out revealing too much information, the paste statement was relayed to us by the manufacturers, you can figure that out for yourself if you'd like, not just a statement put out there by a anet member. But if someone knows more than Boeing and Thales, be my guest, go ahead and post your information. This is why folks are bailing on this thread.

I'm bailing too. You can pick up a copy of any physical chemistry textbook and try and understand my point. (I studied using Atkins, though there were others). The scientific terms for the three phases are solids, liquids and gases. Sometimes vapours and gases are interchangable, in some contexts.

From memory, the post was a claim that a paste was somewhat not a liquid or didn't posses a liquid component. In any case, there weren't any links supplied for me to consider the original source.

If you've the ability to determine that my criticism of scientifically-incorrect statements, independent of the source, albeit non-referenced, originated with yourself, well, that's impressive.

My GBP 15.40 experiment with a.net, has been exactly that- an experiment.

I'm bailing from both the thread, and the forum, and have no plans to contribute, nor lurk, again.

With thanks and regards

B-2319.


User currently offlineart From United Kingdom, joined Feb 2005, 3341 posts, RR: 0
Reply 12, posted (1 year 2 months 2 weeks 6 days 13 hours ago) and read 31451 times:

Assuming (a) the cause of the overheating problem were identified (b) a fix had been designed, built and tested to a level where it would be acceptable to FAA (c) a fix for the containment issue had been designed, built and tested to a level where it would be acceptable to FAA, how long would it take the FAA to certify the aircraft as being safe again?

Once the aircraft were certified as safe, how long would it take to put the revised components into production and start installing them on the 787's delivered so far?

Would it be a few weeks between a solution to the problems being found and installation starting? Several (2/3/4) months?

Anyone have any idea how long the aicraft delivered will remain on the ground after a remedy is devised and approved?


User currently offlineCALTECH From Poland, joined May 2007, 2004 posts, RR: 27
Reply 13, posted (1 year 2 months 2 weeks 6 days 12 hours ago) and read 31008 times:

Quoting b2319 (Reply 12):
I'm bailing too. You can pick up a copy of any physical chemistry textbook and try and understand my point. (I studied using Atkins, though there were others). The scientific terms for the three phases are solids, liquids and gases. Sometimes vapours and gases are interchangable, in some contexts.

So what you know is learned from a book. Interesting.

Quoting b2319 (Reply 12):
From memory, the post was a claim that a paste was somewhat not a liquid or didn't posses a liquid component. In any case, there weren't any links supplied for me to consider the original source.

The memory point is incorrect and way off the mark. No where was it stated that it was not a liquid or didn't posess a liquid component, that has been inserted from a fallible memory. There were no links, it is what has been said by those who work with the batteries. Boeing is where the info comes from. Again, if you have info that shows Boeing has it wrong, please by all means please post it.

Quoting b2319 (Reply 12):
If you've the ability to determine that my criticism of scientifically-incorrect statements, independent of the source, albeit non-referenced, originated with yourself, well, that's impressive.

Think It was my post that first brought up that the electrolyte is more of a paste than a liquid such as those found in lead acid batteries. A incorrect post #260 was made in the last thread #5, that was impressive, ' I joined a.net because, in part 3 of this thread, someone said the electrolyte "wasn't a liquid, it was a paste". What an absolutely ill-informed post if there ever was one. '

So excuse me if there is a issue with your "absolutely ill-informed post."



UNITED We Stand
User currently offlineLN-KGL From Norway, joined Sep 1999, 961 posts, RR: 4
Reply 14, posted (1 year 2 months 2 weeks 6 days 12 hours ago) and read 30644 times:

Quoting sweair (Reply 8):
Someone needs to develop a JET-A fueled fuel cell quickly..

It's called an APU sweair


User currently offlinesweair From Sweden, joined Nov 2011, 1804 posts, RR: 0
Reply 15, posted (1 year 2 months 2 weeks 6 days 12 hours ago) and read 30569 times:

Quoting LN-KGL (Reply 18):

A fuel cell is a bit kinder to the environment than the APU as that is a small jet turbine itself. A fuel cell can use multiple fuels and create less pollution and noise. Maybe the cost and the heat is a problem?


User currently offlineflyglobal From Germany, joined Mar 2008, 558 posts, RR: 3
Reply 16, posted (1 year 2 months 2 weeks 6 days 11 hours ago) and read 30251 times:

Quoting seahawk (Reply 10):
Looking at the Tesla Roadster electric car for example, I find it interesting that the individual cells are so small in their design, yet they still use an active cooling and heating system to control the individual battery packs. Even the space between each cell seems much larger in relation to the cell size, than in the Boeing solution:

I know it is a little of topic but interesting: http://www.teslamotorsclub.com/showt...SS%29

And so will be other LI Car battery systems, like the Chevy Volt and newer Toyota's. Automotive use requires you to have your batteries at Winter in Canada and Russia (-40°C) and also at 100°C at least for heat (Death Valley, India, to name some location).
This requires heating devices and also ventilation and cooling ducts for the batteries.

For Air Planes the design requirements are different - less environmental temperature span at the battery location.

In one of the earlier threads I mentioned that I know that for Chevy it took rather 1/3rd effort for the Cell development and selection its self, 1/3rd for the packaging of the cells and 1/3rd for Power electrics and especially micro controls, software and data calibration.

For Automotive all is about warranty offer. A Chevy, a Toyota and probably as well the Tesla will only charge and discharge between 20 and 80% of capacity, depending on environment etc., charge and discharge is controlled depending on various parameters. Remember the Chevy Volt which caught fire about 2 weeks after a crash test.
A containment and updated procedures after accuidents have been the results.

My gut feel is that we will see something like this as a solution for the Dreamliner:
1) A specific fire and smoke monitoring system, as well as additional temp sensors (probably incl. a camera will be installed)
2) Software, and data cal regarding charging and discharging strategies will be updated in direction of 'more conservative)
3) A regular Battery exchange cycle will be established (like a bottle deposit and return system in Europe)

4) Boeing in the meantime will work on an update of the battery system with a different less risky battery system and get this extensively tested and certified (maybe in 2 years from now) and also will develop a PIP for existing planes for that.

This is what my crystal ball sees coming down the road (air).

Regards

Flyglobal


User currently offlineDocLightning From United States of America, joined Nov 2005, 18676 posts, RR: 58
Reply 17, posted (1 year 2 months 2 weeks 6 days 11 hours ago) and read 29784 times:

Quoting sweair (Reply 19):

A fuel cell is a bit kinder to the environment than the APU as that is a small jet turbine itself. A fuel cell can use multiple fuels and create less pollution and noise. Maybe the cost and the heat is a problem?

1) They are still a new and unproven technology.

2) They run at 400-800°C, which brings up a whole array of thermal containment issues for certification.

3) They would have to crack the fuel for hydrogen and then combine it with oxygen, leaving us to do what with the carbon?


User currently offlinesweair From Sweden, joined Nov 2011, 1804 posts, RR: 0
Reply 18, posted (1 year 2 months 2 weeks 6 days 10 hours ago) and read 29632 times:

Quoting DocLightning (Reply 19):

I wont have to be hydrogen, it can be jet fuel or methanol or any other hydrocarbon source for a fuel cell. Airbus and Boeing are both researching fuel cells. One day we could do away with the apu and batteries. Its sadly no option on the 787.

But to be an optimist, maybe this incident will lead to greater efforts to make the fuel cell a viable option for commercial aviation in the future.


User currently offlineLN-KGL From Norway, joined Sep 1999, 961 posts, RR: 4
Reply 19, posted (1 year 2 months 2 weeks 6 days 9 hours ago) and read 28698 times:

Well, the PAF technology to generate Hydrogen gas from Kerosenes are at an experimental stage and then we are talking about output of only 5kW.



Plasma and hydrogen on a plane to me says: This is even more dangerous than Lithium-ion battery - dare I mention STS-51 Challenger.


User currently offlineDocLightning From United States of America, joined Nov 2005, 18676 posts, RR: 58
Reply 20, posted (1 year 2 months 2 weeks 6 days 9 hours ago) and read 28566 times:

Quoting LN-KGL (Reply 21):
Plasma and hydrogen on a plane to me says: This is even more dangerous than Lithium-ion battery - dare I mention STS-51 Challenger.

I think fuel cells on planes are an inevitability. I just am very doubtful that it will be one of the earlier applications. I think we'll see vast batteries of fuel cells powering ships before one flies aboard an airliner.


User currently offlinesweair From Sweden, joined Nov 2011, 1804 posts, RR: 0
Reply 21, posted (1 year 2 months 2 weeks 6 days 9 hours ago) and read 28514 times:

The small consumer fuel cells are fueled with methanol, quite expensive but people like them as they work 24/7 compared to solar power on boats etc Almost no noise as well.

They do create waste heat though. Fuel cells for vehicles seem to be towards hydrogen.


User currently offlinePC12Fan From United States of America, joined Jan 2007, 2378 posts, RR: 5
Reply 22, posted (1 year 2 months 2 weeks 6 days 8 hours ago) and read 28351 times:

Quoting sankaps (Reply 3):
Well -- they are being proactive right now!

Like they did after two events that could have been catastrophic?? No, the FAA acts as they always have - reactive.



Just when I think you've said the stupidest thing ever, you keep talkin'!
User currently offlinesankaps From United States of America, joined Jan 2008, 2252 posts, RR: 2
Reply 23, posted (1 year 2 months 2 weeks 6 days 8 hours ago) and read 28014 times:

Quoting PC12Fan (Reply 24):
Like they did after two events that could have been catastrophic?? No, the FAA acts as they always have - reactive.

Well, if that is your definition of reactive, then no new airplane or technology would ever fly. There is a "tipping point" at which one must act. Waiting too long would be reactive. Acting too early would just kill all innovation. Acting at the tipping point, before something calamitous happens, is prudent and proactive (in that they don't wait for an actual crash before they act).


User currently offlinepliersinsight From United States of America, joined May 2008, 485 posts, RR: 0
Reply 24, posted (1 year 2 months 2 weeks 6 days 8 hours ago) and read 27958 times:

Quting flyglobal: "And so will be other LI Car battery systems, like the Chevy Volt and newer Toyota's. Automotive use requires you to have your batteries at Winter in Canada and Russia (-40°C) and also at 100°C at least for heat (Death Valley, India, to name some location)."

Are you taking battery compartment temps or air temp. I'm not so sure the air temperature reaches 100C (212F) in Death Valley. I've never been to India.....


25 tdscanuck : Fortunately for all of us, airplane's aren't designed to Murphy's Law...otherwise they'd never fly. Murphy's Law does get applied to individual compo
26 abba : I think Airbus has (or is in the process) as well - If my memory serves me well, it was to substitute the APU.
27 alfablue : Another comment which barely reflects facts or knowledge. The 787 is (or was) ETOPS certified and those Transatlantic tracks are not fixed. They chan
28 Post contains links sweair : http://www.technologyreview.com/news...693/fuel-cells-take-to-the-runway/ http://oilprice.com/Latest-Energy-Ne...en-Fuel-Cell-Powered-Aircraft.html Yo
29 tdscanuck : The comment I was replying to specifically referenced severe turbulence. I didn't repeat "severe" because I was typing quickly (shame on me) and was
30 thunderboltdrgn : Actually it did happened two weeks ago when a commuter train crashed into a house. Caused by a chain of events/factors so unlikely that they together
31 Post contains links PHX787 : http://www.japantoday.com/category/n...l-unable-to-find-cause-of-787-fire This is nuts. Wouldn't they be better off with a replacement source of elect
32 Kaiarahi : May I inject a small dose of reality. The probability of a thermal runaway, coupled with severe turbulence that somehow throws a paste electrolyte in
33 AeroWesty : Which stranded pax? Anyone disrupted in the first couple of days were long ago reaccommodated, and those on flights continuing to be cancelled are be
34 packsonflight : Come on, you know better. Every certification requirement, and that includes the special Li ion certification requirement, is issued for the whole ce
35 cornutt : Hmm... I wonder if they have a concern about the external venting. Were that to become blocked early in a battery event, say by melted material, coul
36 tdscanuck : Yes, for those that are stranded. Are there any left? Generally not. Even if that were the policy (and it's not), DOT has zero jurisdiction on what h
37 Post contains links vivekman2006 : OMG No! Nowhere on this planet does the air temperature reach 100C (212F) Not even close! 100C is the temperature at which water boils and is absolut
38 Post contains images lightsaber : Sadly, I think that is likely. At least for a bit. Besides otherwise mentioned limitations, fuel cells are heavy for the power delivered, have a slow
39 nycdave : Have been fascinated and (sometimes) enlightened by these threads. Just hoping that in this latest iteration we can at least avoid the "it's a politic
40 Post contains images KELPkid : I just hope that when all is said and done, if the FAA's calls of the sky falling proves to be baseless, then someone makes those heads go rolling
41 tdscanuck : That's certainly a good option...it would be consistent with all the FAA/NTSB comments I can think of so far and explain their concerns. Without seei
42 packsonflight : As I understand this, the special condition say that battery fire should contained and not pose a danger to other system, and this goes for the whole
43 beau222 : I tried reading through the entire topic from 1-6 and did not see this questions posted. Does the 748 series use the same type of battery or batteries
44 ComeAndGo : Not in nature but in a Sauna you can go up to 120 deg C. Humidity is zero, though. . . . and I've been in 135F in Palm Springs
45 Aesma : You quote a post that you have not understood at all, apparently. You just made me think of something. You're talking about the venting of the batter
46 cornutt : Interesting point. How much smoke would be generated, and how toxic would it be? Although if the outflow valve was completely blocked, I think the wh
47 JoeCanuck : The FAA approved the containment...and for the most part, the containment did it's job; it prevented the spread of fire, significant damage from fire
48 rwessel : If you had H2/O2 powered fuel cells, you'd need enough power to open the valves to the tanks, assuming the tanks were pressurized. You'd also need so
49 Post contains links AngMoh : Automotive specification for max temperature for components: Cabin mounted components: max operating temp 85 deg C Components mounted in engine bay:
50 Unflug : I don't think that air temperature is relevant in this case, we are talking about limits for car batteries. I am quite sure that the inside of a blac
51 seahawk : Well, I would say the containment worked reasonably in the first incident, but failed in the second. Flammable liquids (or paste) must not escape the
52 flyglobal : To make thinks clear: we talk about a car which stays in the sun in 45°C for lets say 2-3 hs. It heats up quickly above the outside temperature. At
53 Post contains links rotating14 : I was watching the news ticker and saw something close to the link below. Looks like the investigation is shifting from the battery itself and now to
54 Post contains links XT6Wagon : To me the FAA has been reasonable. The grounding while largely fueled by Media Frenzy, does make cautionary sense until they get a handle on the comm
55 Post contains links faro : Some new developments from Reuters: http://www.reuters.com/article/2013/...mliner-japan-idUSBRE90R05C20130128 Difficult to see whether this will have
56 seahawk : Please read my post correctly. I said flammable liquids, this does not mean 100% containment. I am fully aware that gases must be able to escape in a
57 RickNRoll : Not if you can provide sufficient expansion for the solids, and an escape valve externally for the gases. The existing container was what you have de
58 PITingres : XT6Wagon's statement stands correct. There is no criteria for containment of liquids, flammable or not. The only criterion that matters is that the l
59 7BOEING7 : The forward overboard vent valve while not as large as the aft outflow valve is still large enough that blocking it would be difficult and is not in
60 Post contains links InsideMan : don't know if this was posted earlier, interesting article.... http://www.huffingtonpost.com/2013/0...ive-japan-eased-saf_n_2564630.html
61 Kaiarahi : Which does make me wonder how they'll react when a consumer device lets go in the cabin with serious damage. Of the 132 incidents documented so far b
62 Stitch : No. I's probably NiCad (747s before the 747-400 use lead acid).
63 mham001 : I don't know about others but these batteries only get hot under heavy discharge/charge. The 787 batts don't see that much use by design. I do think
64 PITingres : Well, maybe. Trouble is that as soon as you take the management circuitry out of the box you have cabling and connectors to worry about, and they fai
65 Post contains links par13del : Article on the BBC, now what. http://www.bbc.co.uk/news/business-21230940
66 rolfen : 7 years to design the battery and they still couldn't get it right?
67 Post contains links sankaps : Excerpt from the Wall Street Journal today: "Shortly after the Federal Aviation Administration issued safety rules in 2007 for using lithium-ion batte
68 spacecadet : Now they move on to looking at other parts of the electrical system, or to the design of the battery itself. It does not mean they're at a dead end,
69 Post contains links frmrCapCadet : There are reports coming out that that are clearing various parts and systems from fault, can one of the experts here tell us what this means. To an a
70 asctty : Thank you, my specific post on this was deleted by the moderators. Lithium Ion batteries are used all over complex industry sectors as part of Uninte
71 seahawk : No obvious fault in the 2 major systems, this is not good.
72 SonomaFlyer : The articles seem to rule out the battery and charging system. I am assuming they rule out any material defect in the assembly of the battery? If the
73 rolfen : I don't think any system can be "cleared" in the sense where it can be absolved from any responsibility. Electrical systems are complex and bugs can
74 DocLightning : It is, and if it turns out that the explanation is "statistical aberration," then it will take many hundreds of thousands of event-free flying hours
75 Kaiarahi : Before everyone concludes that 2+2=22, what the NTSB actually said was that it found no obvious anomalies in the undamaged JL battery (i.e. the forwar
76 rheinwaldner : Lipos don't like cold temperatures. They loose a lot of capacity. Thus the real RC nerds heat them to 40°C before flying in Winter. That's for sure
77 ComeAndGo : it already happened, the airlines will ban Li-Ion's from flight. Virgin Atlantic did so a few years ago.
78 Unflug : No more cell phones, cameras, tablets and notebooks in the cabin? That will be kind of hard to enforce.
79 ba319-131 : Well, if the batteries have found to be 'clear' for duty, this seems to fall back to the electrical system in general. Given the huge amount of electr
80 Post contains images scbriml : That was a short-term issue related to two specific brands of laptop - Dell and Apple had a massive battery recall in 2006 after several battery fire
81 ComeAndGo : According to the NTSB slide presentation each battery cell has a Rupture Valve. Where does the electrolyte go to if it escapes through that valve. And
82 tdscanuck : The "exception" is the "extremely remote" stipulation...the FAA didn't require 100% protection, as they do for any single failure, but allow a (very
83 asctty : The point here is that that batteries are OK if the control system works. Who owns the control system? The battery manufacturer specifies safe parame
84 francoflier : The ban concerns checked luggage, freight, anything that is not accessible in flight. Let's not forget that Li-ion batteries have already downed an a
85 7BOEING7 : If there is smoke in the fwd equipment area the fwd vent valve opens to clear the smoke overbd. It is a several inch hole in the airplane and it woul
86 asctty : This is locking the door after the horse has bolted in safety terms as it will not prevent the battery overhating in the first place. A very complex
87 Post contains images michiganatc : Forgive me if this was already talked about, I haven't had a chance to read through the 750+ posts With the 787's all grounded, what airports did Unit
88 AeroWesty : Location/plane number: IAH: 901, 902, 905 & 906 LAX: 903 NRT: 904
89 7BOEING7 : All I was describing was the present way all the various "holes" in the airplane operate and the fact that the battery spreading goo around probably
90 justloveplanes : If you are referring to the UPS 747, I think that was an entire pallet of Li Ion batteries. A huge amount of stored energy and a potential fireball.
91 rwessel : Into the empty space in the battery case. And if enough boils out of the cells, obviously out the battery case vents and onto the floor of the EE bay
92 RickNRoll : That's one problem. According to the FAA "The battery failures resulted in release of flammable electrolytes, heat damage, and smoke on two Model 787
93 AeroWesty : Idle question: Other than just looking at the photo of the EE bay from the JAL plane, has there been any indication what other than the battery pack w
94 RickNRoll : Another question. Wouldn't Boeing have had to do a battery failure containment test during certification. Given the design of the container, I would a
95 Stitch : BECAUSE THE SPECIAL CONDITIONS DO ALLOW THE CONTAINMENT VESSEL TO LEAK ELECTROLYTES. If it did not, it risks explosion. That is why the top of the con
96 RickNRoll : Which does not answer the question. If the events now would have been pretty well identical to the tests then, why is it different now?
97 spacecadet : The NTSB has made it clear that they're not going to accept fires on airliners, period. As various people have said, there's always going to be that
98 ComeAndGo : Right, but if one cell is dying and the others are fine the potential short circuit could contribute to more doom, fireworks and fire. And there is n
99 Post contains images Stitch : That I would like to know, myself. JA804A operated for a year without a problem. 10 months with one battery and 3 months with another. And NH has thr
100 macc : [quote=DocLightning,reply=74] what if they cant establish any reasonable cause? in the end, they probably need more data. that is incidents. will they
101 2175301 : This may be a silly point - but I disagree that the NTSB has said that in the way you imply they have said it. The jet engines have fires in them. Pi
102 Aesma : I didn't think there would be a pressurization problem if the valve in one of the EE bay was blocked by a burning battery, if it came to that the pres
103 RickNRoll : You are talking about the cause, not the containment. That would have been tested too, wouldn't it?
104 Stitch : I'm assuming it was as I can't see the FAA not requiring such validation. I've asked for details, but so far nobody has provided any. I'm assuming th
105 Aesma : They're fine with very controlled combustion. When we say that an engine is on fire we rarely mean it's functioning as intended. Some gliders can be
106 alberchico : wait didn't the FAA grant a waiver allowing these birds to be flown back to their home bases ?
107 packsonflight : Possibly this was never tested, and the FAA relayed on documents provided by Boeing. I guess now when on two occasions the battery have failed it did
108 PanAmPaul : I'm not sure but the LOT 787 wasn't even covered by the FAA grounding and I was told it was still in Chicago as of two days ago.
109 cornutt : Actually, if I understand this right, there is. There's an overboard vent connected to the containment; it's clearly visible in one of the photos on
110 cornutt : The FAA doesn't grant blanket waivers for those sorts of things; an airline that wanted to ferry their planes would have to ask for waivers for each
111 Viscount724 : The EASA (EU equivalent of the FAA) issued their own grounding order almost immediately after the FAA order was issued.
112 7BOEING7 : If it was thin enough it would have found a body drain and dripped out of the airplane. I guessing that it was thick and grew thicker as it cooled an
113 7BOEING7 : If its the photo of the airplane with the two insets showing "stains" down the side of the airplane, the botttom inset shows the fwd overboard vent v
114 Post contains links tdscanuck : It's important for the main battery, not really for the APU battery. The APU battery really has no foreseeable purpose in flight, since the only time
115 Post contains images DocLightning : I just got the most hilarious mental image... Yes, well that's what I'm worried about. What if they simply cannot ascertain a cause? At what point do
116 tdscanuck : The FAA almost never tests anything themselves as part of certification (they do their own R&D and investigation testing though). They, or their
117 RickNRoll : It's not the answer to the cause, I was referring to the containment requirement. If the cause is never found, it will likely be even more important.
118 7BOEING7 : If the both packs fail, pressurization can't be maintained and the pilot descends to the lowest safe altitude or 10.000 ft whichever is higher. Depen
119 RickNRoll : But the FAA says "The battery failures resulted in release of flammable electrolytes, heat damage, and smoke on two Model 787 airplanes." Am I readin
120 gemuser : EASA would be authority to issue a wavier for the LOT aircraft BUT it would also need the agreement of all countries under the flight path, because o
121 rheinwaldner : Probably minor ones compared to whatever happened. But I agree, that the BMS does not depend on its location for it to function. And that there is no
122 DocLightning : Because in order to contain all of the temperature and pressure in that fire, it would have to be made of 6"-thick steel plate.
123 justloveplanes : That makes sense of course, and totally understandable. It might be possible to take the position, however, that a contained combustion event is not
124 Post contains links seahawk : In any container that can have an overpressure event, you obviously do not weld it shut, but you have exhausts for the gases and spare storage room f
125 JoeCanuck : NiMh has an even greater power density than Li-ion...but has a much lower power to weight ratio. They are slightly heavier than NiCd's, just as relia
126 gigneil : It is a Saft CVH531KA, a 20-cell, 53 Ah 24V NiCad rechargeable pack. It weights exactly 96 pounds. NS
127 BEG2IAH : It has been mentioned 50+ times in these threads that thermal runaway results in release of gasses and many posters want to have the battery sealed s
128 rheinwaldner : You speak about fire, pressure and temperature. I only about leaked electrolytes. These are two things. Stitch wrote with large letters, that leaking
129 seahawk : I dare say that it is not really rocket science to built a containment vessel that keeps the liquids in and lets the gas out. Even if the liquids sho
130 RickNRoll : It doesn't say "fluids or gases that may escape", it says "NO corrosive fluids or liquids that may escape", there is a big negative at the start of t
131 seahawk : Well it would also depend on what you define as the battery. If the baterry is just the cells and the charger and the metal box around it is the conta
132 justloveplanes : NiMH does sound interesting. Obviously seems more stable than LiIon? Less prone to runaway? Same current delivery (Per Ah reserve) and recharge cycle
133 Post contains images keegd76 : Just my own 2 cents. Based on my own line of work there would [probably] have been a separate environmental requirement for the battery as opposed to
134 prebennorholm : NiMH has higher capacity than NiCad. But unfortunately NiMH has by far the highest internal resistance when cold of all relevant battery types, inclu
135 tdscanuck : I was just talking about that with some friends last night...the short answer is, I don't know, because I don't think anyone has been in this situati
136 Stitch : The grammar is perfectly clear to me - if corrosive fluids or liquids do escape they may not damage surrounding structures. So the FAA and NTSB have
137 vzlet : Any reason why it wouldn't work to just enlarge the dimensions of the battery case by an inch or two and and use it as a (secondary) container for th
138 Shenzhen : Me thinks they will add a bunch of inspections (maint) and procedures (flight crew) and once an airline has met the requirements they will be allowed
139 tdscanuck : The only obvious issue I can see is that I'm sure there's some clearance requirement between the battery and surrounding parts, precisely to avoid me
140 strfyr51 : look guys, Everybody is going on and ON about the Lithium-Ion Batteries and their safety, But NOBODY seems to question the Manufacturer OF said batter
141 cornutt : Don't underestimate the amount of work that it might take to do that. Some sensors, particularly passive things like thermocouples, often rely on the
142 sankaps : But would it be any different if the grounding were the result of a crash due to a battery fire? They would still have to find the root cause, no?
143 AeroWesty : No, the ANA plane was one of the first delivered. And there have been 50 deliveries. As a passenger, I don't even know what to make of malarkey such
144 Aesma : You could make it an aluminum box with some fins in the direction that is clear of obstacles, it would help dissipate the heat of potential leaks.
145 max999 : I'm appalled and angry that some people on here have suggested that the 787 was grounded prematurely and then comparing to past aircraft (737 crashes,
146 tdscanuck : Steel box. Wrapping flaming lithium with potentially flaming aluminum will likely not pass muster with the FAA. Well, groundings don't happen very of
147 cornutt : If it was, say, 2 cm aluminum plate with fins, the fire would have to get pretty damn hot.
148 sankaps : ADs have very specific actions / fixes specified. The FAA cannot issue an AD if they don't know what to recommend to fix the problem. Therefore their
149 Post contains links tdscanuck : Sure they can. For example: "As a result of an in-flight, Boeing 787 battery incident earlier today in Japan, the FAA will issue an emergency airwort
150 ComeAndGo : Or make it out of expandable kevlar. So when the battery blows the container just expands rather then rupture.
151 ComeAndGo : because in other Li-Ion battery failures the battery did not explode but rather became so hot that it started combusting adjacent material.
152 SonomaFlyer : The containment box has to be made from a material which will not chemically react with the battery electrolyte nor catch fire itself. Aluminium isn't
153 justloveplanes : Extensive use of fins for heat transfer to can direct high temperatures away from other surfaces also.
154 Post contains links rcair1 : (5) No corrosive fluids or gases that may escape from any lithium ion battery may damage surrounding structure or any adjacent systems, equipment, or
155 JoeCanuck : Right...lb/amp hour. NiMh may not be certified and NiCd's are tried and true...it's hard to beat something that just works, doesn't cause any drama w
156 cornutt : Soooo... any news today? I haven't seen any.
157 BEG2IAH : So after all this discussion you are suggesting that battery should be sealed and you expect FAA to certify a bomb to be used on an aircraft? Interes
158 tdscanuck : There are two potential problems there...unless you're very clever with the Kevlar design, it would be really hard to guarantee the expanding case do
159 Post contains links spacecadet : Here's a wrinkle that I personally haven't seen talked about, and I believe I have been following these threads I thought pretty closely: Elon Musk re
160 packsonflight : All the solution that require any change or modification of equipment, that needs to be re certified, like a different battery, new charger or a new
161 tdscanuck : I'm not sure how that makes the NTSB happy...their current angle seems to be that it's simply unacceptable for the battery to catch fire. Having only
162 Post contains links BoeingVista : Boeing knew of problems with the 787 batteries, ANA changed 10 batteries between May and December 2012 http://www.nytimes.com/2013/01/30/bu...re-the-f
163 Shenzhen : ANA having replaced 10 batteries doesn't (in my opinion) mean there is widespread issues with the 787 batteries. What it does say is that 10 batterie
164 BoeingVista : 10 batteries and chargers were replaced over a fleet of 17 aircraft and you don't think this is significant? But of course when these batteries were
165 phxa340 : If you didn't cherry pick the article to fit your agenda is also mentions Boeing and ANA didn't report the battery changes because they were a reliab
166 JoeCanuck : Ah...I must have missed it. Thanks. Still...the vast majority of posters seem to agree with the grounding...if little else.
167 Shenzhen : How old is the battery on a phone before they start seeing a little less performance and lower voltage. I wonder what the expected "on wing" time for
168 Shenzhen : I used google to see if the MRBR is available on the internet. It wasn't, but did find the report for the 767. For the battery, this is what is requi
169 Post contains links flood : "At least 100 batteries failed on Boeing 787" http://seattletimes.com/html/busines...020241385_787deadbatteriesxml.html The Times also ran an article
170 spacecadet : Well, let's go back to the discussion on what constitutes "fire". If you strengthen containment, improve cooling, make the cells smaller and space th
171 rheinwaldner : I agree. I have said it many threads ago already. That has been required right from the start and I still think it is realisticly doable. But I also
172 RickNRoll : Sounds like the existing (necessary) safe guards for the LiIo batteries are so restrictive that they render any advantages not worth the trouble in p
173 BoeingVista : The Seattle Times article says 100 - 150 batteries failed fleet wide, I don't see how Boeing can have 100 plus Li-ion batteries plus multiple fail kn
174 RickNRoll : A lot of them havn't failed, if they just get to 15% capacity they lock themselves out, and have to be returned to the manufactuer to be reset and rec
175 AeroWesty : Because you have to actually read the article rather than react to its title: ----- "Most of the batteries were returned because they had run down so
176 JoeCanuck : The battery in the video is a Lithium Iron Phosphate battery...a chemically different battery than the ones found on the 787. It reacts differently t
177 wjcandee : Not necessarily, given that the article says that some ran down or locked out because mechanics incorrectly disconnected them. Sounds like this may b
178 AeroWesty : Ink from the life vest demos, IIRC.
179 BoeingVista : At least 2 batteries clearly were, and these were not amongst the 100 returned. How many more? You know, I believe thats some people only believe a s
180 AeroWesty : What would be accomplished looking for a fire threat when the reason for their return was "battery disconnected improperly" or "battery allowed to ru
181 7BOEING7 : "Most of the batteries were returned because they had run down so far that a low-voltage cutout was activated" Which part of this do you not understa
182 JoeCanuck : That, if it worked, wouldn't solve the certification problem since it would have to be tested and proven as much as any other design, and probably mo
183 XT6Wagon : and how many seat covers have been replaced in that time? ok thats a little silly..... so lets go for How many tires? How many brakes? Some things ar
184 astuteman : Either that or it proves that ANA were not aware of the underlying safety issue... In terms of the way a complex system fails, operator error combine
185 FlyingAY : Considering the nature of a LiIon battery, I think the system should automatically try to prevent a situation where the battery gets too empty and mu
186 seahawk : I would say it is not uncommon for a new technology to have some problems at the start. Although I must say it would have been interesting to know if
187 flood : Yes, I should have been more descriptive, sorry. If I'm not mistaken the 787's batteries are cobalt-based whereas the A350's Saft battery is manganes
188 ComeAndGo : then why is this happening ?
189 FlyingAY : LiIon batteries hardly are a new technology. Not even in an airplane. Well, it could be that at the time when the batteries were changed it was not a
190 AirlineCritic : The report about large number of batteries being returned is interesting. (If true, as always.) Remember that the 787 had a very extensive flight test
191 ComeAndGo : it's very simple it's mentioned in the Seattle Times article. This battery will drain in less then one hour if used by ramp personal when servicing th
192 Post contains links art : The lithium ion batteries installed on the Boeing 787 are inherently unsafe, says Elon Musk, founder of SpaceX and owner of electric car maker Tesla.
193 BoeingVista : Most doesn't mean all, you seem to have trouble understanding that. Are seat covers at risk from spontaneous combustion? If they were I'd be interest
194 AeroWesty : Perhaps you can explain the obvious I'm missing then. I accept that once a battery falls below a certain threshold while it's powering aircraft syste
195 Post contains images Unflug : Understandable But thanks anyway!
196 JerseyFlyer : Intuitively this makes sense. An explanation from Boeing for their choice of eight large cells when presumably they discounted options comprising lar
197 sankaps : The AD was to ground the aircraft. That is, as I said, the only logical option they have if they do not know the root cause of a recurring failure wi
198 BoeingVista : Over discharge of a Li-ion battery can lead to it short circuiting and that can lead to thermal runaway, it does not need to be recharged to be poten
199 AeroWesty : When you say "over discharge", is your meaning discharging too quickly or discharging below a certain value, or both?
200 RickNRoll : A normal battery doesn't need that special handling. A normal battery doesn't need to be returned to the manufacturer if it goes flat. These batterie
201 Post contains links sebolino : "Even Mr. Leahy" ? You think he's an idiot ? You mean, not like this ? http://www.youtube.com/watch?v=9WKdI-KVWtc
202 ncfc99 : I'm with Boeingvista on this, Boeing and ANA may have thought it to be a reliability issue, I can live with that, but with the 2 major battery incide
203 rheinwaldner : This information is a hint that the BMS is designed wrongly. If a large number of batteries is killed by discharging them too much, the charging/disc
204 UALWN : The article also says that "The frequency of battery failures reflects issues with the design of the electrical system around the battery, said the p
205 keegd76 : Just for clarification, what is the battery in question being used to power? I thought I read earlier that it was a back-up supply for the cockpit ins
206 AeroWesty : I don't see where I've ever denied that. BoeingVista still hasn't made his case for why these singular incidents of batteries running down while the
207 oneskyjet : 4-6 Months? If you seriously believe that, it's time to short Boeing stock. They gotta get this thing flying a lot sooner than that.
208 BoeingVista : I did and you replied to it. The batteries run down until they get to a damaged state ie, need replacement. A battery that has rundown into an under
209 Post contains links parapente : This thread is so long it is hard to know what has and has not been reported. I wondered whether this recent article had been posted - I could not see
210 AeroWesty : And my point is that a lot of the incidents were due to mishandling/operator error, and you're using this 100-150 headline number as all encompassing
211 ncfc99 : Maybe i'm being dumb but I can follow Boeingvista's train of thought (maybe wrongly), but not yours. I'm not understanding why you need each battery
212 AeroWesty : Okay, real simple terms. Line up 100 blenders on your kitchen table. I take a sledgehammer to 95 of them and make them inoperable (operator error). O
213 Post contains links trex8 : http://www.defense-aerospace.com/art...ttery-ills-before-ana-failure.html Not an expert but at least with ANAs battery issues it isn't clear to me fro
214 AeroWesty : Okay, I read that link. It's incomplete. You have to read the Seattle Times article in reply #169 and read the next few replies to get the full gist
215 RottenRay : Did you read either article? At All!? There were not "100 to 150 failures," there were that many replacements. -- Some were discharged to their lower
216 Post contains links and images flood : Looks like Boeing is going full steam ahead "It said it plans to manufacture between 635 and 645 Dreamliners by year-end" "Overall, Boeing says it pla
217 Post contains links robffm2 : aero.de and airliners.de are both running today an article from DPA. There it says: 'In the industry, some consider a delay of one to two years for p
218 Post contains links max550 : I think he might be on to something. With about 2,400 Tesla Roadsters on the road I can't find a single report of a fire involving their li-ion batte
219 rheinwaldner : I have no idea. A starting point would be to check the use cases in what situations current is drawn from the batteries. In a sense the low voltage d
220 Post contains images keegd76 : That's a mistake right?? Unless we're talking toy planes
221 ncfc99 : Not a good comparison in my opinion. A) thats sabotage, not operater error, B) I expect better than a 5% failure rate of the batteries used in aviati
222 RottenRay : I missed where there were 100 destroyed batteries, only that those which had been discharged past a certain level had to be returned as their safety
223 AeroWesty : You have to go back and read the Seattle Times article. It wasn't 100 destroyed batteries because of over-discharging. Many, many were disabled simpl
224 BoeingVista : Nope. Why should I bother, you can come to the realisation that there is a widespread problem and come on board or not in your own sweet time, no ski
225 ncfc99 : But to my mind they are directly linked by one thing, the batteries. What is making the batteries fail or have to be replaced is the big question, IM
226 tdscanuck : New aircraft change *far* more parts than that (in number terms). You can't lump economic problems (which is what part replacements without safety ef
227 seahawk : How often does a mechanic have to disconnect those batteries?
228 par13del : So does this mean that the FAA and Japan authorities are also investigating whether workers followed the proper procedures when they changed these ba
229 AeroWesty : Not a clue.
230 Post contains links LTC8K6 : http://seattletimes.com/html/busines...020241385_787deadbatteriesxml.html The article only seems to mention one ANA battery failure out of 10 replaced
231 LTC8K6 : Your a/c compressor is not running when you start your car, unless your car is very old. Doesn't matter if you leave the a/c turned on, the compresso
232 trex8 : from that link "However, she acknowledged that there has been a series of problems and listed %u201Cthe top three reasons for Boeing returning batter
233 cornutt : DIdn't I see the number 2000 hours somewhere up the thread? So many posts...
234 RottenRay : Actually, the three items I mentioned - discharged to safety interlock levels, expired, and faulty - were directly quoted from a Boeing employee. As
235 ncfc99 : Maybe I'm over complicating or over analyzing things. Either way, I know i'm getting a headache try to get my head around it. That much is obvious. I
236 BoeingVista : This isn't what the article says, it say that "Most of the batteries were returned because they had run down so far that a low-voltage cutout was act
237 tdscanuck : Replaced != destroyed. According to the articles, most were pulled for expiration (not destroyed) or the low-voltage interlock cutting in to *prevent
238 markalot : * I'm not qualified. Got that out of the way. The thing about the battery failures that I think might be relevant is that it exposes an issue, operat
239 Post contains images keegd76 : Thanks for the info. Do Yuasa also supply the charging system for the battery? If so then I'd assume they would have tested the failsafe mechanism fa
240 ncfc99 : I fear I maybe one of tose 'people' that you are refering to. From what I can gather from your posts, I have assumed the batteries would have more ca
241 ncfc99 : Thanks. That should give us a vague idea of how many got replace due to being expired. That there is......
242 cornutt : That leads to circular logic, though... If you have a system that stops drawing current from the battery before it bricks, well, now you can't draw c
243 Shenzhen : You sure about this? All the control / indication is on the re-fuel panel. I could see the fuel quantity system, and a few valves and lights. At leas
244 Stitch : They're rendered unusable aboard the airplane using the airplane's charging system. However, they can be reconditioned off the airplane and returned
245 PITingres : That's exactly what the design does. How is that not clear? The operator does something that drains the battery, if he/she keeps doing it long enough
246 7BOEING7 : Based on the large amount of battery problems I'm guessing Boeing already had engineers and the vendors working on that issue -- is this where the "my
247 spacecadet : My guess as a project manager - because that's the only way I know to approach this - is that in the absence of a "smoking gun", you're going to see
248 Shenzhen : I don't really believe that re-fueling or towing is the main cause for battery replacements. I can't think of too many occasions when an airplane woul
249 PITingres : I'm not seeing the connection. Not saying that there isn't, but I don't see how you can logically conclude that battery self-shutoff due to low charg
250 cornutt : No, that's Securaplane, with some involvement from Thales although I'm not sure what their role is.
251 RottenRay : Great post, Space, except for this last paragraph. The ANA battery wasn't in use when this voltage glitch appeared, and therefore, wasn't connected t
252 AeroWesty : A question I asked early on, but never got answered, was how long it takes from a 'battery event' which would cause a thermal runaway, and the actual
253 PlanesNTrains : Sadly, he's neither. There is a more nefarious reason that may be present. But that's not for me to decide. LOL A couple of important comments: and W
254 tdscanuck : I said they discharged in service...I have no idea how that conflicts with what you're saying or what the articles are saying. If you run the battery
255 trex8 : Perhaps the issue is that the charging system on the two planes which had an incident were malfunctioning and the batteries were left in a dangerousl
256 FlyingAY : Thank you for taking the time to answer me. So what you are saying, this is not true what Seattle Times writes: "At that stage, the batteries, which
257 cornutt : That would be the built-in battery management rather than the charging system, if I understand the design, but your point holds. It's possible that t
258 Stitch : As The Seattle Times statement appears written as it was a blanket statement, then yes, it is incorrect. If they had specifically noted that the batt
259 Shenzhen : Really nothing more then any other airplane except releasing the brake (if set) and applying the brake after the tow. I wounder if it is a standard o
260 7BOEING7 : The brakes are electric not hydraulic.
261 Shenzhen : Sorry, was talking airplanes in general (battery for 787 and accumulator for airplanes with hyd brakes). Cheers
262 Post contains images rheinwaldner : These batteries are essentially dead. It is written in the article with those words. So the article basically confirms that the battery lacks capacit
263 Shenzhen : Boeing CEO...... Responding to questions from analysts and reporters, McNerney said people and resources are not being diverted from other areas to so
264 Shenzhen : If the battery no longer provides any power to the airplane because it turned itself off doesn't mean it is dead at the component level, but certainl
265 scbriml : I think we need to use something like "disabled by design", maybe? It is clear that batteries in this state are unusable, but not damaged. They can e
266 RottenRay : I guess you'll have to choose who you trust with regards to technical info regarding the 787: A reporter with limited knowledge, or Tom, who lives an
267 Post contains links AeroWesty : Okay, this sure made me blink. In the LA Times article regarding Boeing's fourth-quarter earnings call with analysts: "Boeing expects earnings this ye
268 PITingres : This has all been gone over, above. Do you really think that ground handling time on battery alone wasn't part of the agreed-on spec accepted by a su
269 Post contains images Stitch : And that is incorrect as a blanket statement. The batteries cannot be recharged on the plane. The batteries can be recharged outside the plane. And n
270 tdscanuck : That's certainly a possibility, although I think the FAA/NTSB said they found no fault with the charger, didn't they? Although, even if the charger/B
271 trex8 : What did you expect them to say?? They said similar with the 737NG production issues 15 yrs ago. Gee, I think I'm still writing off some of my capita
272 SonomaFlyer : Thanks for the info Tom. It looks like there is a disconnect in the reporting which isn't a huge surprise given the technical nature of the issues and
273 max550 : That sounds very likely, it just seems to me that the battery design is an especially weak point. In my very limited experience with hybrid and elect
274 AeroWesty : That was prior to Sarbanes-Oxley, which came into effect in 2002. Even though I'm on the record that I expect most of the costs of the grounding for
275 XT6Wagon : Its possible that Boeing (or its suppliers) was already working on upgrading the batteries to the latest chemistry, and other advances. If so, it lik
276 Post contains images AirlineCritic : Folks, you are relying on news articles that might be incorrect, or at least not tell the whole story. Some batteries got changed, in addition to the
277 starrion : I thought SOX would require Boeing not to make obviously false statements to the press also, but if you consider that Boeing was blithely saying that
278 tdscanuck : I'm not sure how you relate a handling error to running the battery down. The battery has a finite capacity (measured in time, for maintenance purpos
279 abba : No matter what (we do not need to spilt hair here) - is this indicative of a deeper design flaw? The designers not knowing precisely how much power t
280 scbriml : At this point in time, they can't really say anything else. Until the root cause of the 787 issue has been identified, nobody knows how much it will
281 AeroWesty : Not necessarily. Knowing that you will have costs vs. not knowing you'd have an unexpected delay are two different things. When Boeing announced 787
282 Kaiarahi : Yes, they announced last week that they found no anomalies with the BCU (Securaplane). At the same time, they also said the BMS (Kanto) circuit board
283 Post contains links nomadd22 : http://www.flightglobal.com/news/art...ttery-fundamentally-unsafe-381627/ Gotta say I've come to agree with Elon's philosophy over the years. "Both Bo
284 tdscanuck : The designers know exactly how much power the systems need to draw in normal operation and how much time the battery can sustain that load. Then they
285 abba : Are you sure that there would be no way you could have known about that in advance? To me it seems as if someone hasn't done his/her homework properl
286 rcair1 : Intuition is not always right. Perfect example - "intuitively" a quad should be more reliable than a twin. But - what we see populating the skys is a
287 cornutt : I've been wondering about that ever since the rumor about the software update started circulating. Thinking about it in the context of what you said,
288 Kaiarahi : That would be Yuasa + Kanto + Securaplane.
289 Post contains images Shenzhen : A quad has twice as many engines when compared to a twin, therefore the reliability has to be lower (everything else being equal) at the airplane lev
290 RickNRoll : Wouldn't it be better to shut it off before it gets to the point where it locks itself? Would save everyone a lot of time and trouble.
291 Post contains links ComeAndGo : except that the charging has to be done at the OEM in Japan. So in other words the battery is useless. no, they have to be sent to the OEM in Japan t
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