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Topic: FAA Grounds 787, Part 10
Username: 777ER
Posted 2013-02-17 15:25:01 and read 32796 times.

Link to previous thread FAA Grounds 787, Thread 9 (by 777ER Feb 9 2013 in Civil Aviation)

WARNING: Due to thread 9 going off topic quickly and turning into a 'battle ground', the moderators will be watching this thread frequently and ANY offending/rule breaking posts will be removed. Please respect each others right to have their opinion.

[Edited 2013-02-20 00:15:16 by SA7700]

Topic: RE: FAA Grounds 787, Part 10
Username: mjoelnir
Posted 2013-02-17 15:49:39 and read 32792 times.

The Boeing solution, mentioned in The Seattle Times, of a robust containment should hopefully be enough to get the B 787 flying again. It takes care of the safety aspect. I really do not think that the flying public will take a burning battery safely contained worse than for example a failing engine.

Topic: RE: FAA Grounds 787, Part 10
Username: jetblueguy22
Posted 2013-02-17 15:56:46 and read 32723 times.

Quoting mjoelnir (Reply 1):
I really do not think that the flying public will take a burning battery safely contained worse than for example a failing engine.

I'm going to have to disagree with you on that. People hear fire and airplane in the same sentence and it really freaks them out. No matter if it a roll burning in the galley ovens or the battery, people get really uncomfortable. I like Boeing and would fly the 787 the moment it was back in service, but the general public doesn't understand the complexities and how safe the plane would be with a true permanent fix.
Pat

Topic: RE: FAA Grounds 787, Part 10
Username: PHX787
Posted 2013-02-17 15:57:15 and read 32722 times.

OK so to recap some, Japanese airlines (NH, JL) have cancelled 787 flights through the end of March, and LO through the end of October....... What about UA, AI, and QR? I find it quite hard to follow these threads to keep up.

Topic: RE: FAA Grounds 787, Part 10
Username: BestWestern
Posted 2013-02-17 16:20:21 and read 32605 times.

Quoting mjoelnir (Reply 1):
The Boeing solution, mentioned in The Seattle Times, of a robust containment should hopefully be enough to get the B 787 flying again.

This is nothing more than a rumor of a possible solution to an unknown problem. Boeing have said nothing publicly of the concept.

I too hope that this containment is approved so we can relaunch aircraft before the northern summer peak, but I really fear that we are looking at the end of the IATA Summer schedule before aircraft will be relaunched. We then fall into the trap of aircraft arriving when they are least needed - the start of the winter timetable.

Topic: RE: FAA Grounds 787, Part 10
Username: NAV20
Posted 2013-02-17 17:07:40 and read 32450 times.

Quoting BestWestern (Reply 4):
This is nothing more than a rumor of a possible solution to an unknown problem.

More information here:-

"Boeing is set to propose a short-term fix for batteries on its grounded 787 Dreamliner passenger jets, according to a report by the Seattle Times.

"The Seattle Times reports Boeing will propose building fireproof titanium or steel containment boxes around lithium ion battery cells that, in the event of a fire, would vent gases outside of the plane. The newspaper reports Boeing could submit the proposal to the Federal Aviation Administration as early as this week in an effort to get 787s flying again by May.

"Boeing is simultaneously working on a comprehensive redesign of the batteries in a process that could take nine months or longer, according to the report."


http://www.stltoday.com/business/col...b-836d-56c7-a249-033003a4607e.html

Topic: RE: FAA Grounds 787, Part 10
Username: BestWestern
Posted 2013-02-17 17:25:07 and read 32367 times.

NAV20, thats a repost from another article with a more positive spin - no new information at all from St Louis.

From the original article: http://seattletimes.com/html/busines...ology/2020373450_boeing787xml.html


"Boeing will not disclose any details of the solutions it is working on."

"investigators have still not pinpointed the cause."

"it’s unclear if the FAA is ready yet to accept containment of an overheated battery cell rather than prevention."

"the short-term fix will take at least three months to design, test, certify and retrofit,"


And from an analyst in that article...

“Boeing is trying to play it down to some degree, hopeful the solution is just around the corner,”

“We believe the grounding costs Boeing over $25 million a month in direct costs, and the total cost to Boeing could be over $1 billion.”

"Doubtful that Boeing will easily persuade regulators to let the 787 return to service soon."

"Polish national airline LOT on Thursday declared it’s not planning on having its 787s back in service before October. “I think even October is optimistic,” said Pilarski."

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-17 17:28:11 and read 32344 times.

Quoting jetblueguy22 (Reply 2):
eople hear fire and airplane in the same sentence and it really freaks them out. No matter if it a roll burning in the galley ovens or the battery, people get really uncomfortable. I like Boeing and would fly the 787 the moment it was back in service, but the general public doesn't understand the complexities and how safe the plane would be with a true permanent fix.

Just guessing here, but I would expect that once Boeing has proven they have a containment system robust enough to survive a battery fire that consumes the entire battery (so it burns the maximum time), such a fix will be considered sufficient to allow the 787 to return to service, but Boeing will still be ordered to either develop a more stable Lithium-Ion battery or switch to a NiCad-based replacement.

As for the flying public, I would not be surprised if it quickly moves to the back of their mind and then out of their conscious thought as people have short attention spans.

Topic: RE: FAA Grounds 787, Part 10
Username: KFLLCFII
Posted 2013-02-17 17:38:00 and read 32298 times.

Quoting NAV20 (Reply 5):
"The Seattle Times reports Boeing will propose building fireproof titanium or steel containment boxes around lithium ion battery cells that, in the event of a fire, would vent gases outside of the plane.

Would the combination of such a box and the Lithium-Ion battery end up weighing close to what a conventional Ni-Cad installation would be?

Topic: RE: FAA Grounds 787, Part 10
Username: BestWestern
Posted 2013-02-17 17:38:16 and read 32285 times.

Quoting Stitch (Reply 7):
I would not be surprised if it quickly moves to the back of their mind and then out of their conscious thought as people have short attention spans.

Agree 100% - the news cycle has become very short indeed. I really hope that this aircraft is up and flying before the Summer peak - however I fear it will be longer.

Topic: RE: FAA Grounds 787, Part 10
Username: NAV20
Posted 2013-02-17 17:51:54 and read 32255 times.

Quoting BestWestern (Reply 6):
no new information at all from St Louis.

Agreed, BestWestern, not confirmed by Boeing. On the other hand, though, it's the only thing that Boeing CAN propose? The alternative - spending upwards of a year re-designing and re-certifying the aeroplane with totally-different batteries - is just about 'unthinkable' in business terms. It would mean thousands of lost jobs, not just at Boeing but among all the suppliers worldwide; and untold amounts of money having to be found to compensate the customer airlines. I don't think it's an exaggeration to say that the 'spiralling costs' of that sort of scenario might result in the whole of Boeing having to close down?

My guess is therefore that the proposal will be made - and, further, that the FAA will eventually approve it.

[Edited 2013-02-17 17:53:55]

Topic: RE: FAA Grounds 787, Part 10
Username: ZKCIF
Posted 2013-02-17 18:17:38 and read 32110 times.

Quoting BestWestern (Reply 6):
We believe the grounding costs Boeing over $25 million a month in direct costs

if this is true, the direct costs are next to nothing. a couple of brand new 737s per month will cover that easily  
Quoting BestWestern (Reply 6):
the total cost to Boeing could be over $1 billion.”

What does THIS mean? Do they run into a 1-billion-loss if the delay is 6 months long? 9 months long?

I tried to calculate very roughly the expenses for airlines.
I am likely very far off the mark but my idea is:
The lifetime of a 787 is 25 years as that of any other contemporary plane. In 2037, there will be far superior planes anyway.
The acquisition costs of one plane probably were in the area of 120 million USD (heavy discounts for early frames, etc.)
one plane is expected to operate for about 9000 days (25yrs*365 days minus heavy checks).
when the plane is on the ground, it gets no extra cycles and requires comparatively little maintenance thus has insignificant costs in terms of spares, etc.
as a result, each day of grounding costs 120mil/9000days= 13,333USD of the plane's value, and one month is 400,000USD worth. how far off the real mark am i? thanks a lot for your answers.

[Edited 2013-02-17 18:24:46]

Topic: RE: FAA Grounds 787, Part 10
Username: prebennorholm
Posted 2013-02-17 18:24:59 and read 32080 times.

Quoting bonusonus (Reply 222):
Where did the 2.5 times heavier value come from? I have an MIT paper showing that Li-ion has a specific energy of 150 Wh/kg, compared to 50 for Ni-Cad.

The Yuasa LVP65 spec sheet, which has been linked several times in these threads, tells that energy density is 101 Wh/kg. Those 150 Wh/kg indicated by MIT is more like dreaming, or hopefully a typo.

Maybe MIT was looking at only the active interior of the cell, without the supporting structure, connectors and such. But a cell in the shape of a wet towel in a plastic bag isn't very useful.

50 Wh/kg for Ni-Cad is also on the optimistic side. 40 is more like a realistic average.

But these number naturally vary with maker and other specs, such as how rugged they are designed to be.

Topic: RE: FAA Grounds 787, Part 10
Username: rheinwaldner
Posted 2013-02-17 21:34:54 and read 31573 times.

Quoting Stitch (Reply 7):
Just guessing here, but I would expect that once Boeing has proven they have a containment system robust enough to survive a battery fire that consumes the entire battery (so it burns the maximum time), such a fix will be considered sufficient to allow the 787 to return to service, but Boeing will still be ordered to either develop a more stable Lithium-Ion battery or switch to a NiCad-based replacement.

How to proove a containment?
IMO Boeing should build 10 of them and let burn down 10 batteries within the aircraft. After that examine the impact. That would be aproper test, that could also restore a minimum of confidence. Generally I agree however with those, who think any other burning battery is not something Boeing or the FAA especially can afford.

Quoting KFLLCFII (Reply 8):
Would the combination of such a box and the Lithium-Ion battery end up weighing close to what a conventional Ni-Cad installation would be?

Not fully, but the advantage starts dissapearing.

Quoting prebennorholm (Reply 12):
Quoting bonusonus (Reply 222):
Where did the 2.5 times heavier value come from? I have an MIT paper showing that Li-ion has a specific energy of 150 Wh/kg, compared to 50 for Ni-Cad.

The Yuasa LVP65 spec sheet, which has been linked several times in these threads, tells that energy density is 101 Wh/kg. Those 150 Wh/kg indicated by MIT is more like dreaming, or hopefully a typo.

About 100 Wh/kg is not really progressive, which is good. Resarch is tackling 600 Wh/kg, but this is something for the future: http://www.greencarcongress.com/2010/05/sion-20100501.html

Topic: RE: FAA Grounds 787, Part 10
Username: jetblueguy22
Posted 2013-02-17 22:00:25 and read 31503 times.

Quoting Stitch (Reply 7):
Just guessing here, but I would expect that once Boeing has proven they have a containment system robust enough to survive a battery fire that consumes the entire battery (so it burns the maximum time), such a fix will be considered sufficient to allow the 787 to return to service, but Boeing will still be ordered to either develop a more stable Lithium-Ion battery or switch to a NiCad-based replacement.

As for the flying public, I would not be surprised if it quickly moves to the back of their mind and then out of their conscious thought as people have short attention spans.

I for sure agree with you on the first part. I think that would absolutely get the 787 back into service. As for the flying public I'm not sure initially. Most probably couldn't pick it out of a lineup if you put it next to a 777 and an A330, but when they are booking that trip to Poland or Tokyo and see that "Aircraft Type:787-8 Dreamliner" some people are going to get nervous. Obviously their fear would be unneeded after the fix, but it may exist. I certainly wouldn't have a problem booking it.
Pat

Topic: RE: FAA Grounds 787, Part 10
Username: BestWestern
Posted 2013-02-17 22:18:12 and read 31438 times.

Quoting ZKCIF (Reply 11):

Over and above the actual costs of the repairs and analysis, The analyst here is also probably including the NPV effect of shunting the entire delivery timetable back a further nine months - $100 in todays money is the same as $88 paid in one year if Boeing have an average cost of capital of 12%.

Delays like this wreck profitability in large projects, throw out company cash flow forecasts, and damage company valuations. Basically what is happening is boeing are manufacturing today for payment in say nine months after completion. Profitable companies go out of business because they run out of cash due to slow payment of bills -this wont happen to Boeing - expect bonds to be Secured - but probably is a part of the worries of the analyst.

Oh the joys of project financing when the shareholder wants a return yesterday. Lucky I'm not an accountant.

On top of this I can only imagine the inventory cost of the dozens of 787s and future parts.

Topic: RE: FAA Grounds 787, Part 10
Username: mke717spotter
Posted 2013-02-17 23:47:02 and read 31204 times.

Quoting PHX787 (Reply 3):
Japanese airlines (NH, JL) have cancelled 787 flights through the end of March, and LO through the end of October

I also reponded to this in another thread, but surely its not going to take THAT long to sort out the battery issue? What's going to happen if the FAA ban gets lifted in May for example? Are they just going to have their five 787s just sit in a corner somewhere until October? Hopefully this isn't set in stone because I'm probably going to Poland in July and was looking forward to flying the 787.

Topic: RE: FAA Grounds 787, Part 10
Username: ADent
Posted 2013-02-18 00:07:09 and read 31052 times.

Quoting mke717spotter (Reply 16):
I also reponded to this in another thread, but surely its not going to take THAT long to sort out the battery issue? What's going to happen if the FAA ban gets lifted in May for example? Are they just going to have their five 787s just sit in a corner somewhere until October?

I would guess they would park the 767s and fly the 787s, just to save fuel costs. Keep the 767s they can't return to the leasers as spares and look for some charter work.

It could be awhile. A month for Boeing to get the fix certified. A month until the first plane is flying. A month to modify the remaining 50 planes. That is 3 months before LOT gets their 2 787s back in the air. Could be more or less.

LOT is just basically saying we are not going to schedule any flights until we see the 787s back in the air. With the 787s long history of delays, IMHO this is not a bad idea.

Topic: RE: FAA Grounds 787, Part 10
Username: Rara
Posted 2013-02-18 01:52:57 and read 30283 times.

Quoting Stitch (Reply 7):
As for the flying public, I would not be surprised if it quickly moves to the back of their mind and then out of their conscious thought as people have short attention spans.

Until, of course, the next battery burns - contained or not.

Let's face it, Boeing is going to need a permanent solution.

Topic: RE: FAA Grounds 787, Part 10
Username: AndyEastMids
Posted 2013-02-18 02:38:01 and read 29946 times.

Quoting Stitch (Reply 7):
Just guessing here, but I would expect that once Boeing has proven they have a containment system robust enough to survive a battery fire that consumes the entire battery (so it burns the maximum time), such a fix will be considered sufficient to allow the 787 to return to service...

That's all well and good, but the first time a 787 with the new containment system rocks up at some airport with streaks of smoke/electrolite down the side ejected by the improved venting system, and lots of engineer-type folks start peering into lower compartments, and it's dragged off to some hangar and the next flight is cancelled... Or a 787 diverts and the fire crews are called out for a suspected battery fire... Someone's going to notice, the press are going to report it... The headlines are going to say something like - even though it was contained and the airplane didn't burn, there's been another 787 battery fire... Not good PR for Boeing, for the airplane, or for the operating airlines. Even with a temporary fix, how many battery further fires can be noticed/reported, even if they're totally and safely contained, before the travelling public and the FAA get the willies? Could the 787 survive with a temporary fix until a permanent fix is introduced, if ongoing evidence of occasional or even regualar battery fires arose?

Topic: RE: FAA Grounds 787, Part 10
Username: cmf
Posted 2013-02-18 02:38:20 and read 29927 times.

Quoting NAV20 (Reply 10):
I don't think it's an exaggeration to say that the 'spiralling costs' of that sort of scenario might result in the whole of Boeing having to close down?

I think you're painting the devil on the wall. I can't see a scenario where scrapping 787 would mean the end of Boeing. Nor can I see a scenario where the 787 is scrapped because of this battery issue. It takes something where there isn't alternatives.

Quoting NAV20 (Reply 10):
My guess is therefore that the proposal will be made - and, further, that the FAA will eventually approve it.

It is a very serious accusation you make with nothing more than prejudice to support it.

Topic: RE: FAA Grounds 787, Part 10
Username: LJ
Posted 2013-02-18 03:32:17 and read 29551 times.

Quoting jetblueguy22 (Reply 14):
Most probably couldn't pick it out of a lineup if you put it next to a 777 and an A330, but when they are booking that trip to Poland or Tokyo and see that "Aircraft Type:787-8 Dreamliner" some people are going to get nervou

The majority of the flying public will forget the problems as soon as it's flying again. You see already that the media attention is not so high (apart from some outlets) thus people will forget (or have already forgotten).

Quoting BestWestern (Reply 9):
I really hope that this aircraft is up and flying before the Summer peak - however I fear it will be longer.

This will be very important for some airlines. Airlines like Norwegian have big plans with the 787 for S13, and missing the Summer peak means missing the most profitable time of the year (and no NYC and BKK for DY this Summer).

Topic: RE: FAA Grounds 787, Part 10
Username: B777LRF
Posted 2013-02-18 04:01:24 and read 29335 times.

There is talk now, from ever increasing circles and not all of them repeating each other, that we're looking at a lengthy delay. The sources usually quotes in very conventional terms; weeks, few months, even a year. While that may be true, in fact it's certain one of them will be, it is, however, an imprecise measurement and unfit for a.net purposes.

To rectify this shortcoming I made some quick calculations on the back of my laptop, partially (well, fully then) based on post counts and sequel numbers on the "FAA Grounds 787, Part xxx" thread. I shall not divulge the intensity of the mathematics used, merely state the results as they came out. Thus I can say, with a level of certainty not uncommon to these boards though equally far removed from actual knowledge, that the 787 will fly again at the exact moment post number 27.501 is published in Part 103 of this thread.

Topic: RE: FAA Grounds 787, Part 10
Username: NAV20
Posted 2013-02-18 04:07:39 and read 29285 times.

Quoting cmf (Reply 20):
I can't see a scenario where scrapping 787 would mean the end of Boeing. Nor can I see a scenario where the 787 is scrapped because of this battery issue.

Misunderstanding, I think (hope?), cmf? I don't see any prospect of the 787 being scrapped - do you? I'm talking about the possibility of the authorities refusing to allow any further use of these batteries, thus forcing Boeing to spend a year or more developing, installing, and certifying new batteries straight away. And that, during that 'year-plus,' Boeing would have to close down the whole 787 production line, suspend deliveries, and compensate both the airlines already flying 787s and the customers counting on deliveries in said year-plus? The costs of any such 'programme' would be simply colossal?

Quoting cmf (Reply 20):
Quoting NAV20 (Reply 10):
My guess is therefore that the proposal will be made - and, further, that the FAA will eventually approve it.

It is a very serious accusation you make with nothing more than prejudice to support it.

For the life of me I can't see how that sentence is in any way an 'accusation'? I'm just saying that Boeing will make the sensible suggestion that they install better 'containments' and then develop and certify more 'foolproof' batteries ASAP. And that the FAA, after full consideration, will agree to that strategy and lift the grounding 'on terms'?

How is that 'accusing' either party of anything?

[Edited 2013-02-18 04:15:49]

Topic: RE: FAA Grounds 787, Part 10
Username: gulfstream650
Posted 2013-02-18 04:45:38 and read 28972 times.

I have a few questions:

1. Fire aside we can all agree that the battery system is faulty. If indeed there is another failure, where will the power come from to power the systems? I understand that the new systems require a quick-charge power source vs. conventional methods.

2. Even if the FAA approves the temporary fix, what will the implications be to the current ETOPS certifications?

Thanks

Topic: RE: FAA Grounds 787, Part 10
Username: BestWestern
Posted 2013-02-18 04:54:32 and read 29558 times.

Quoting gulfstream650 (Reply 24):
we can all agree that the battery system is faulty.

But what caused the fault is as yet, unknown.

Quoting LJ (Reply 21):
This will be very important for some airlines. Airlines like Norwegian have big plans with the 787 for S13, and missing the Summer peak means missing the most profitable time of the year (and no NYC and BKK for DY this Summer).

Hitting the summer peak is critical for all airlines. The whole Norwegian long haul business model is in deep trouble. Their marketing budget is invested, and probably their staffing plans are totally askew. The worst part is the not knowing when the aircraft will be available.

Topic: RE: FAA Grounds 787, Part 10
Username: s5daw
Posted 2013-02-18 04:59:16 and read 29492 times.

Quoting prebennorholm (Reply 12):
The Yuasa LVP65 spec sheet, which has been linked several times in these threads, tells that energy density is 101 Wh/kg. Those 150 Wh/kg indicated by MIT is more like dreaming, or hopefully a typo.

Could it be a difference between stored useful energy and total energy?
I know that LiPo cells must not drop below certain voltage or they go into thermal runaway - indicating there is still energy in them, but we can't use it.

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-18 05:30:27 and read 29943 times.

Quoting BestWestern (Reply 4):
This is nothing more than a rumor of a possible solution to an unknown problem.

I agree with what you are saying but would not describe this as an 'unknown' problem. There's lots known about the problem, unfortunately falling short of the exact reason why it occurred. As above the root cause might not ever be known due to the state the batteries are in, which means you have no better option than to work with the possible root causes, and hope you don't miss any.

Quoting BestWestern (Reply 4):
Boeing have said nothing publicly of the concept.

They, of course, are floating a trial balloon. They leak enough info to someone like Jon who then runs a story, and if it gets shot down they know not to go that way. In this case, the story did have another unnamed regulator say that at this point it's not going to fly, but I suspect with time as other approaches prove to be unfeasible it will gain some traction.

Boeing's got itself between a rock and a hard place.

If they end up going with containment (and presuming FAA lets them) they will need to have a solid public relations campaign ready to go. They'll need some sort of demo showing to the average person that the system will work. How you do that without showing all kinds of nasty things going out the outflow system is beyond me, but a simulation won't be convincing enough, IMHO.

If they don't go with containment, it's clear they have a very long down time facing them, because changing the battery means changing the charging system and a lot more re-certification to do.

Topic: RE: FAA Grounds 787, Part 10
Username: cmf
Posted 2013-02-18 05:50:17 and read 29730 times.

Quoting NAV20 (Reply 23):
Misunderstanding, I think (hope?), cmf?

I've reread your comments multiple times and I don't see a way they can be read different from how I read them the first.

Quoting NAV20 (Reply 23):
I don't see any prospect of the 787 being scrapped - do you?

It will be scrapped on day but due to obsolescence caused by newer products. But it is a long time away. As I said I don't see how it will be scrapped over the battery issue.

Quoting NAV20 (Reply 23):
I'm talking about the possibility of the authorities refusing to allow any further use of these batteries, thus forcing Boeing to spend a year or more developing, installing, and certifying new batteries straight away. And that, during that 'year-plus,' Boeing would have to close down the whole 787 production line, suspend deliveries, and compensate both the airlines already flying 787s and the customers counting on deliveries in said year-plus? The costs of any such 'programme' would be simply colossal?

And I was talking about your conclusions from the effects of a one year grounding which stated as:

Quoting NAV20 (Reply 10):
I don't think it's an exaggeration to say that the 'spiralling costs' of that sort of scenario might result in the whole of Boeing having to close down?

I do not see how a one year grounding would cause Boeing to close down. I don't see how a complete scrapping of the 787 program would shut down Boeing.

Quoting NAV20 (Reply 23):
For the life of me I can't see how that sentence is in any way an 'accusation'? I'm just saying that Boeing will make the sensible suggestion that they install better 'containments' and then develop and certify more 'foolproof' batteries ASAP. And that the FAA, after full consideration, will agree to that strategy and lift the grounding 'on terms'?

How is that 'accusing' either party of anything?

What you suggested, maybe not what you intended to suggest, is that FAA would approve the solution because the costs of having it grounded for a year would be too high. Not because the solution is good enough to make the risks acceptable.

Topic: RE: FAA Grounds 787, Part 10
Username: BestWestern
Posted 2013-02-18 05:53:22 and read 29813 times.

Oh, my blood boils. From the hype before the Qantas purchase, through roll-out through all the delays to the 'dreamliner' the PR team have had far too much influence on the project. If Boeing really believe in their solution- they should come out and say it - and really believe in it..... hiding behind proxies demonstrates a lack of belief in what they are proposing.

The same was the case on the day they rolled out a shell held together with fasteners from Home Depot because of a lucky date - If Boeing were not ready, they should have said it.

Quoting Revelation (Reply 27):
They leak enough info to someone like Jon who then runs a story, and if it gets shot down they know not to go that way

Should we expect the usual 'independent consultants' and the 'independent journalists' to gently massage the FAA/NTSB into submission over the next few months?

Quoting Revelation (Reply 27):
In this case, the story did have another unnamed regulator say that at this point it's not going to fly, but I suspect with time as other approaches prove to be unfeasible it will gain some traction.

Ah, the un-named response to the question that was never asked.....

Boeing needs to put the media handlers back into the containment box and let the engineers get to work in peace.

Topic: RE: FAA Grounds 787, Part 10
Username: NAV20
Posted 2013-02-18 06:38:29 and read 29294 times.

Thanks, cmf - guess that more or less clears our disagreement up.

Quoting cmf (Reply 28):
I do not see how a one year grounding would cause Boeing to close down. I don't see how a complete scrapping of the 787 program would shut down Boeing.

I guess it would come down to 'cash flow,' cmf. On the face of it, and 'stating the extreme case,' Boeing having to compensate lots of airlines for having bought fifty-odd aeroplanes that they aren't allowed to fly any more, for the foreseeable future - and also having to scrap many aeroplanes that have already been built, but can't be delivered and flown - would almost inevitably result in Boeing 'going broke.' But I don't think that will happen - and, moreover, even if it DID happen, 'Boeing' would immediately be replaced by a company called 'Boeing 2013' or something, and life would go on.....  
Quoting cmf (Reply 28):
What you suggested, maybe not what you intended to suggest, is that FAA would approve the solution because the costs of having it grounded for a year would be too high. Not because the solution is good enough to make the risks acceptable.


I see why you could feel that way. But you're quite right that that's not what I intended to suggest. I spent a lot of my working life in the construction field - dealing with all kinds of accidents, on 'both sides' of the argument, firstly in government, later at the 'sharp end.' To put it shortly, Boeing will be arguing that two 'non-fatal' incidents (only one with passengers at any risk) do not justify a complete grounding; and the FAA will be 'considering their position.'

We'll all just have to 'wait and see' where the controversy goes from here........just hope that we're not disagreeing any more. I expect that both of us are just hoping that a 'solution' is found - sooner rather than later.  

Topic: RE: FAA Grounds 787, Part 10
Username: packsonflight
Posted 2013-02-18 06:43:02 and read 29220 times.

Quoting Stitch (Reply 7):
Just guessing here, but I would expect that once Boeing has proven they have a containment system robust enough to survive a battery fire that consumes the entire battery (so it burns the maximum time), such a fix will be considered sufficient to allow the 787 to return to service

I think that it is impossible for the regulators to accept any soulution that does not fully comply with the special conditions set for the Li batteries, and the containment is only part of that. The other part is the instability or failiure rate of the battery. That must be addressed too.

Topic: RE: FAA Grounds 787, Part 10
Username: AngMoh
Posted 2013-02-18 07:32:33 and read 28746 times.

Quoting NAV20 (Reply 5):
More information here:-

"Boeing is set to propose a short-term fix for batteries on its grounded 787 Dreamliner passenger jets, according to a report by the Seattle Times.

"The Seattle Times reports Boeing will propose building fireproof titanium or steel containment boxes around lithium ion battery cells that, in the event of a fire, would vent gases outside of the plane. The newspaper reports Boeing could submit the proposal to the Federal Aviation Administration as early as this week in an effort to get 787s flying again by May.

This was Cessna's solution. It is not certified yet, but the expected time for recertification is 18 months. How can Boeing achieve the same in 3 months? 12 Months I can accept if Cessna's lessons learned are take into account, but 3 months not.

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-18 07:44:47 and read 28556 times.

Quoting BestWestern (Reply 29):
Oh, my blood boils. From the hype before the Qantas purchase, through roll-out through all the delays to the 'dreamliner' the PR team have had far too much influence on the project.

It's hard to argue that, on the basis of the 7/8/07 roll-out alone. On the other hand, there's more than enough reason to include engineering and manufacturing on the wall of shame. Sadly the misdeeds seem to swamp out the good deeds when one considers how far off the mark the program has been and continues to be.

Quoting BestWestern (Reply 29):
If Boeing really believe in their solution- they should come out and say it - and really believe in it..... hiding behind proxies demonstrates a lack of belief in what they are proposing.

I don't know about that. Dealing with public opinion is very difficult. If they would come out strongly in favor of a given plan only to see it not be acceptable then they would have limited their options needlessly.

I do see a movement to have a containment solution pass muster, BUT:

Quoting packsonflight (Reply 31):

I think that it is impossible for the regulators to accept any soulution that does not fully comply with the special conditions set for the Li batteries, and the containment is only part of that. The other part is the instability or failiure rate of the battery. That must be addressed too.

Indeed various figures on the regulatory side have said as much. The real question is the "addressing" part. They can find all kinds of ways to claim to address it. It'll be interesting to see how they proceed.

Topic: RE: FAA Grounds 787, Part 10
Username: DTW2HYD
Posted 2013-02-18 07:50:34 and read 28492 times.

Quoting BestWestern (Reply 25):
But what caused the fault is as yet, unknown.

Layman's guess would be Electonic Window Tinting + Sophisticated AVOD with Big LCD + Color Shifting LED lighting.

Software fix for the battery system in combination wtih Sleep Masks + Printed Material should do the trick to get these birds flying again in no time.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-18 07:51:53 and read 28622 times.



Quoting Rara (Reply 18):
Let's face it, Boeing is going to need a permanent solution.

And Boeing has at least 90 engineers in Japan working on it.


Quoting gulfstream650 (Reply 24):
If indeed there is another failure, where will the power come from to power the systems?

The batteries are the last and final power source for aircraft systems. The primary power source are the generators in the engine. The secondary power source are the generators in the APU. And the tertiary power source is the RAT. Only if both engines shut down, the APU shuts down and the RAT fails to deploy would the systems be using the batteries.



Quoting gulfstream650 (Reply 24):
Even if the FAA approves the temporary fix, what will the implications be to the current ETOPS certifications?

It depends. If Boeing takes up a 787, sets fire to a battery and flies in circles for 330 minutes and the plane operates normally...



Quoting NAV20 (Reply 30):
I guess it would come down to 'cash flow,' cmf. On the face of it, and 'stating the extreme case,' Boeing having to compensate lots of airlines for having bought fifty-odd aeroplanes that they aren't allowed to fly any more, for the foreseeable future - and also having to scrap many aeroplanes that have already been built, but can't be delivered and flown - would almost inevitably result in Boeing 'going broke.'

Such a scenario would require the 787 to be the only source of cash for The Boeing Company which you know is not the case.

Boeing is delivering 35 737s a month at a 20% profit margin per some sources. They're also delivering 8 777s a month at likely an even higher profit margin. The two 747s Boeing are delivering each month may or may not be profitable, but the two 767s they are delivering each month definitely are. And then there are all the ancillaries Boeing Commercial is selling at significant profit margins and all the product being delivered by IDS and other Boeing units, all evidently at a profit per Boeing's quarterly statements.

For 2012, Boeing's Operating Cash Flow was over $7.5 billion, an 87% increase over 2011. And when you consider those 47 787s that Boeing delivered lost them anywhere from scores to hundreds of millions of dollars each (in terms of sales price versus delivery cost), the rest of the company must really be cranking out cash.

As such, I cannot even remotely believe that if Boeing does not deliver a single 787 in 2013 and increases their undelivered inventory backlog by scores of frames that this will mean the company will become insolvent and have to file for Chapter 13 reorganization or Chapter 7 liquidation.

  



Quoting packsonflight (Reply 31):
I think that it is impossible for the regulators to accept any soulution that does not fully comply with the special conditions set for the Li batteries, and the containment is only part of that. The other part is the instability or failiure rate of the battery. That must be addressed too.

And I have offered the opinion that it will be addressed through switching to a more stable cathode type. But that can be addressed later, once a sufficiently robust containment system is developed and installed to insure that if the battery enters thermal runaway and catches fire it will not endanger the aircraft or it's systems.

[Edited 2013-02-18 07:55:14]

Topic: RE: FAA Grounds 787, Part 10
Username: cmf
Posted 2013-02-18 08:36:48 and read 27937 times.

Quoting NAV20 (Reply 30):
I guess it would come down to 'cash flow,' cmf.

It is always down to cash flow so, sure. But Boeing's financials are strong. They have a lot of cash flow from other programs. The programs that have kept the company going while pumping fortunes in to the 787 program. They have some 13 BUSD in cash for immediate expenses.

R&D and most WIP is already paid for so that will not have much negative impact on cash flow. What will cost is return of deposits and penalty charges to customers and probably to suppliers. However, as noted above they have plenty of cash and much more importantly solid positive cash flow from other programs.

In the end they would be required to take a gigantic write off but that is mostly paper and will only affect the year it is taken.

I fail to find support for your concern.

Quoting NAV20 (Reply 30):
I see why you could feel that way. But you're quite right that that's not what I intended to suggest. I spent a lot of my working life in the construction field - dealing with all kinds of accidents, on 'both sides' of the argument, firstly in government, later at the 'sharp end.' To put it shortly, Boeing will be arguing that two 'non-fatal' incidents (only one with passengers at any risk) do not justify a complete grounding; and the FAA will be 'considering their position.'

I can't see FAA willing to take the risk of there being another incident unless they have solid foundation to believe it will be contained.

As much as Boeing want to get the plane in the air I can't see them taking that risk either. That could actually force them to shut down as people would start questioning the safety of other models.

Quoting NAV20 (Reply 30):
I expect that both of us are just hoping that a 'solution' is found - sooner rather than later.

I have no doubt they will find a solution. Even if it means going back to old technology. It will take the time it takes. Everything else is too risky.

Quoting Stitch (Reply 35):

I wish I had read your argument before I typed in mine  

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-18 08:40:46 and read 27893 times.

Quoting Stitch (Reply 35):
And I have offered the opinion that it will be addressed through switching to a more stable cathode type. But that can be addressed later, once a sufficiently robust containment system is developed and installed to insure that if the battery enters thermal runaway and catches fire it will not endanger the aircraft or it's systems.

You seem to be implying that the FAA will suspend the failure rate part of the special condition until "later", even though the NTSB and others have stated that it is a concern?

Topic: RE: FAA Grounds 787, Part 10
Username: justloveplanes
Posted 2013-02-18 10:00:43 and read 27104 times.

Quoting AndyEastMids (Reply 19):
That's all well and good, but the first time a 787 with the new containment system rocks up at some airport with streaks of smoke/electrolite down the side ejected by the improved venting system, and lots of engineer-type folks start peering into lower compartments, and it's dragged off to some hangar and the next flight is cancelled...

I think Boeing is on the right track. To restate some previous comments, containment design can be very straightforward... Explosion proof containers for sensitive electronics, motors and other gear are off the shelf items in the off shore oil industry to protect against fire on oil rigs. The requirements for containment in these situations is protection against sparks in a continuously explosive hydrocarbon environment - which exceeds significantly what is necessary for a burning airplane battery emitting electrolyte in a non flammable EE bay.

The problem with these solutions is that they are (naturally) very heavy, and so are only a temporary solution as they are massive overkill from a design prospective. But say the solution is 200 lbs (about the weight of a passenger, it could be more) and saves months of downtime, it seems to me Boeing should have proposed this earlier.

This solution as a practical manner eliminates the thermal hazard at a reasonable operating cost, even if a container needs to be custom machined vice off the shelf (the design parameters for such a vessel are commonly in use in the industry). Make it big enough, with surfaced electrical connections and one might not even need the vent. The component becomes a self contained battery unit that upon failure is opened up, battery replaced, leads reattached and off you go.

Bulky, expensive and clumsy, but intrinsically fail-safe by design and industry practice and will buy time for a proper fix. I can't see how the NTSB would object to 100% isolation of combustion from the fuselage environment. One still needs to deal with the released heat, which seems to be fine as is.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-18 10:32:51 and read 26811 times.

Quoting Revelation (Reply 37):
You seem to be implying that the FAA will suspend the failure rate part of the special condition until "later", even though the NTSB and others have stated that it is a concern?

As I read it, the immediate need is for Boeing to develop, test, and confirm to the FAA's satisfaction that they have a containment system that will successfully withstand the most catastrophic battery failure - something along the lines of the battery catching fire and completely burning all available fuel - without that failure impacting flight-criticial systems or the structural integrity of the airplane. At that point, the failure rate is no longer a primary safety concern because if you have a failure, it will not result in damage to the airframe or a hull loss and the aircraft can successfully and safely make a landing at an alternate field within whatever time limits the FAA allows (and the FAA may very well be very conservative in this matter as it applies to ExTended OPerationS).

However, a high failure rate will be a cost-concern to the airlines because if the FAA (or their local regulatory authority) is very conservative about how far away they can operate from a diversion point and/or they have to routinely divert airplanes and/or replace batteries and containment systems because the incident rate remains high, they're not going to accept that for very long.

As such, a "foolproof" containment system should be sufficient to return the 787 to service, it will not be, IMO, an acceptable resolution in and of itself. The failure rate will need to be reduced, as well.

Boeing and their subs will subsequently have to develop a lithium-ion battery that is sufficiently damage-tolerant and stable that it has a failure rate similar to NiCad batteries. If they cannot develop such a battery, then they will most likely be forced to change the system to NiCads to restore dispatch reliability to a level the airlines will accept.

Topic: RE: FAA Grounds 787, Part 10
Username: RickNRoll
Posted 2013-02-18 10:58:47 and read 26496 times.

Quoting Stitch (Reply 35):
And Boeing has at least 90 engineers in Japan working on it.

Don't forget the "Mythical Man Month". This is going to take time, no matter how many engineers you put on the job. I do agree that Boeing is doing all it can to get the 787 in the air ASAP, it's not going to be worried about how much it has to spend to do so.

Topic: RE: FAA Grounds 787, Part 10
Username: glbltrvlr
Posted 2013-02-18 11:08:47 and read 26380 times.

Quoting jetblueguy22 (Reply 14):
see that "Aircraft Type:787-8 Dreamliner" some people are going to get nervous.

Most people have no clue what type of aircraft they are flying on, even if it is printed on the itinerary. But if the airlines see it as a problem, it's easily overcome. Recall Super 80?

Topic: RE: FAA Grounds 787, Part 10
Username: rheinwaldner
Posted 2013-02-18 11:11:13 and read 26367 times.

Quoting s5daw (Reply 26):
Quoting prebennorholm (Reply 12):
The Yuasa LVP65 spec sheet, which has been linked several times in these threads, tells that energy density is 101 Wh/kg. Those 150 Wh/kg indicated by MIT is more like dreaming, or hopefully a typo.

Could it be a difference between stored useful energy and total energy?

No, the stated energy densities does only consider energy that can be unloaded. You are correct, that a small rest will always stay in the battery. Like some fuel stays in the tank, even when the engine already have stopped running...

Quoting justloveplanes (Reply 38):
Bulky, expensive and clumsy, but intrinsically fail-safe by design and industry practice and will buy time for a proper fix. I can't see how the NTSB would object to 100% isolation of combustion from the fuselage environment. One still needs to deal with the released heat, which seems to be fine as is.

And with the volume expansion. Otherwise you'd have a spectacular bomb. So it never will be 100% isolated from the outside.....

Quoting Stitch (Reply 39):
As I read it, the immediate need is for Boeing to develop, test, and confirm to the FAA's satisfaction that they have a containment system that will successfully withstand the most catastrophic battery failure - something along the lines of the battery catching fire and completely burning all available fuel - without that failure impacting flight-criticial systems or the structural integrity of the airplane

Others have judged this approach as unsufficient, as the FAA would have to clear a solution that still violates elementary requirements issued by themselves. They got a bloody nose the first time, when they certified the current design, and I can't imagine, that they will say: "We certified burning batteries in error the first time, when we did not know, and now we should recertify the same batteries for public flight while we know that they don't pass our initial criteria???" Very optimistic and not very likely to turn out that way IMO.

Beside that how would you test that? A single flight with the burning battery would be a nice idea, but not enough IMO. E.g. structural integrity has to be tested beyond to be expected loads. How can you simulate a battery that burns more than to be expected?

A wild proposal would be, to conduct multiple tests, each with batteries, that have 150% of the actual batteries capacity....

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-18 11:16:55 and read 26305 times.

Quoting Stitch (Reply 39):
As I read it

I don't know what you are reading, but it would seem to be quite inconsistent with the well known "special conditions". I guess time will tell if such an alternate construction would be allowed.

Topic: RE: FAA Grounds 787, Part 10
Username: kanban
Posted 2013-02-18 11:43:12 and read 26023 times.

Quoting justloveplanes (Reply 38):
The component becomes a self contained battery unit that upon failure is opened up, battery replaced, leads reattached and off you go.

the battery in the containment box is a line replaceable unit (LRU) with external plugs. the unit would never be opened in the plane but sent to a certified repair station (which may or may not be the airline). Looking at the spaces occupied by the battery boxes, I would venture the new one will be slightly larger for and aft and side to side. However there is room to make it taller.. so maybe they raise the battery so dripping electrolyte goes to a pan below.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-18 11:48:43 and read 26037 times.

Quoting Revelation (Reply 43):
I don't know what you are reading, but it would seem to be quite inconsistent with the well known "special conditions".


Special Condition 1 appears to be met with the current design based on reports the charging system passed inspection, however investigators continue to look into the charging system so I will withhold final judgment at this time.

Special Condition 2 appears to have been violated in terms of a self-sustaining increase in temperature, but newer cathode chemistries have been designed to address that so changing the cathode chemistry to one of those new formulas should bring the battery back into compliance with this condition.

Special Condition 3 was met in both incidents.

Special Condition 4 was met with the current design.

Special Condition 5 was met in both events, however the FAA is concerned this may not be the case in a future event. Therefore, a more robust containment system needs to be developed to ensure it is met in the severest of cases (including those considered "extremely remote").

Special Condition 6 was definitely met in the case of JA804A and appears to have been met in the case of JA829J.

Special Condition 7 was met with the current design.

Special Condition 8 was met with the current design.

Special Condition 9 was met with the current design.




Quoting rheinwaldner (Reply 42):
Beside that how would you test that? A single flight with the burning battery would be a nice idea, but not enough IMO. E.g. structural integrity has to be tested beyond to be expected loads. How can you simulate a battery that burns more than to be expected?

The battery has a finite element of consumable fuel so once that level is reached, combustion can no longer continue.



Quoting rheinwaldner (Reply 42):
A wild proposal would be, to conduct multiple tests, each with batteries, that have 150% of the actual batteries capacity....

That would show how well the material can withstanding heat and pressure, even if the containment vessel was not representative of the one that would be installed in the 787's bay (as it would be 150% the size).

Topic: RE: FAA Grounds 787, Part 10
Username: Kaiarahi
Posted 2013-02-18 12:12:09 and read 25748 times.

Quoting Revelation (Reply 27):
They, of course, are floating a trial balloon. They leak enough info to someone like Jon who then runs a story, and if it gets shot down they know not to go that way.

Why would Boeing bother communicating with the FAA through the press when they're working directly with them (and the NTSB) every day?

Quoting cmf (Reply 36):
I can't see FAA willing to take the risk of there being another incident unless they have solid foundation to believe it will be contained.
Quoting Stitch (Reply 39):
As such, a "foolproof" containment system should be sufficient to return the 787 to service, it will not be, IMO, an acceptable resolution in and of itself
Quoting rheinwaldner (Reply 42):
Others have judged this approach as unsufficient, as the FAA would have to clear a solution that still violates elementary requirements issued by themselves. They got a bloody nose the first time, when they certified the current design, and I can't imagine, that they will say: "We certified burning batteries in error the first time, when we did not know, and now we should recertify the same batteries for public flight while we know that they don't pass our initial criteria???"

Lest everybody forget, the initial FAA "fix" after TWA800 was simply a minimum fuel requirement for the centre wing tank, despite widespread concern over aspects of the design and certification of the 741/2/3 (heat transfer from air conditioning packs located beneath the tank). The 744s continued to fly despite the design/certification issue and pax did not apparently avoid them. As the NTSB investigation advanced (it took 5+ years), further ADs were issued for inspection and replacement of specific electrical devices and wiring that could potentially be a source of ignition.

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-18 12:31:23 and read 25534 times.

Quoting Kaiarahi (Reply 46):
Lest everybody forget, the initial FAA "fix" after TWA800 was simply a minimum fuel requirement for the centre wing tank, despite widespread concern over aspects of the design and certification of the 741/2/3 (heat transfer from air conditioning packs located beneath the tank). The 744s continued to fly despite the design/certification issue and pax did not apparently avoid them. As the NTSB investigation advanced (it took 5+ years), further ADs were issued for inspection and replacement of specific electrical devices and wiring that could potentially be a source of ignition.

That's true, however considering the extremely small number of events ( 1-747, 2-737 ??) compared to the number of flights the odds of another event were very small. The center wing fuel requirement made the odds even smaller and now every airplane off the line has the tanks inerted. I don't think the 787 will get away that easily.

Topic: RE: FAA Grounds 787, Part 10
Username: RayChuang
Posted 2013-02-18 12:43:33 and read 25421 times.

My guess (personally!) is that Boeing's ultimate solution is to switch to a dry electrode lithium-ion battery--a newer-style battery design not so prone to battery fires. I wouldn't be surprised that Boeing is funding this research--especially since it will allow the size of lithium-ion battery pack to be smaller, providing even more fuel savings or longer range.

Topic: RE: FAA Grounds 787, Part 10
Username: gulfstream650
Posted 2013-02-18 12:48:07 and read 25308 times.

I really don't see how an organization such as the FAA would allow this tempory fix to suffice in order for revenue flights to proceed.

It just simply isn't an acceptable solution in this day and age and you can bet that if there is indeed another incident takes place you can be sure that the media will have a field day and Boeing will suffer.

I understand aviation and the risks but I don't think that I would be comfortable to fly on a 787 until this issue if PROPERLY FIXED. The proposed temporary fix if nothing other than glorified bush mechanics.

If the plane is allowed to fly as Boeing proposes, it will be nothing other than the result of a good 'ol USA back room political play.

Not acceptable.

Topic: RE: FAA Grounds 787, Part 10
Username: Kaiarahi
Posted 2013-02-18 12:54:51 and read 25248 times.

@ 7BOEING7
You may be right (especially since the FAA has a brand new administrator who's likely to be cautious at the beginning of his mandate), but the FAA authorised the fuel quantity fix in the face of public hysteria about "flying bombs" that was probably higher than that surrounding the 787.

[Edited 2013-02-18 12:56:08]

Topic: RE: FAA Grounds 787, Part 10
Username: ComeAndGo
Posted 2013-02-18 14:10:10 and read 24597 times.

Quoting Rara (Reply 18):
Let's face it, Boeing is going to need a permanent solution.

My post was deleted.

In the article in the Seattle times it confirms that Boeing sent 90 engineers to Japan to design a new battery. ThIs new battery will be the permanent fix. The temporary fix is the reinforcement of the battery container with a gas evacuation tube. This temporary fix is to get the aircraft flying again asap.

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-18 14:15:40 and read 24661 times.

Quoting Stitch (Reply 45):
Special Condition 2 appears to have been violated in terms of a self-sustaining increase in temperature, but newer cathode chemistries have been designed to address that so changing the cathode chemistry to one of those new formulas should bring the battery back into compliance with this condition.

Thanks for the clarification. It wasn't clear to me that the post I replied to (#39) included changing the chemistry. If you're including that, such an approach will take a lot longer to develop/manufacture/test/certify than a containment-only solution, so some might see it as a non-starter.

Quoting Kaiarahi (Reply 46):
Why would Boeing bother communicating with the FAA through the press when they're working directly with them (and the NTSB) every day?

Lots of reasons: (1) To not have to go on the record with FAA asking about it at this point in time (2) to not make the FAA go on the record with their answer at this point in time (3) To see what the public reaction will be, which may or may not be similar to the FAA's.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-18 15:03:27 and read 24277 times.

Quoting Revelation (Reply 52):
It wasn't clear to me that the post I replied to (#39) included changing the chemistry. If you're including that, such an approach will take a lot longer to develop/manufacture/test/certify than a containment-only solution, so some might see it as a non-starter.

I was and yes it will.

This is why I could see the FAA not forcing Boeing to park the plane until the new battery is ready provided they have a containment system guaranteed proven to protect against a major fire and/or electrolyte leak with the current battery to return the 787 to service in the interim.

That way, you first prevent the current battery from causing a crash / hull loss / injury / death, and you also ensure a safer battery is put into place as yet another level of protection. Passenger safety is not compromised during the development of the new battery and Boeing and airlines are able to return to operation.

Topic: RE: FAA Grounds 787, Part 10
Username: Wolbo
Posted 2013-02-18 15:26:05 and read 24088 times.

Ostrower tweeted this link to a short Boeing video on the 787 batteries and questioned who it was given to.

Topic: RE: FAA Grounds 787, Part 10
Username: BestWestern
Posted 2013-02-18 15:53:45 and read 23938 times.

Quoting Wolbo (Reply 56):
Ostrower tweeted this link

Ostrower should ask his buddies in Boeing that question.

Alas He feels all left out by boeing... "It definitely was not members of the media" boo hoo.

Topic: RE: FAA Grounds 787, Part 10
Username: cmf
Posted 2013-02-18 16:01:05 and read 23861 times.

Quoting Kaiarahi (Reply 46):
Lest everybody forget, the initial FAA "fix" after TWA800 was simply a minimum fuel requirement for the centre wing tank

Difference is they had a fix they felt addressed the problem they had identified as the cause.

Topic: RE: FAA Grounds 787, Part 10
Username: stasisLAX
Posted 2013-02-18 16:07:25 and read 23867 times.

Quoting Revelation (Reply 27):
Boeing's got itself between a rock and a hard place.

If they end up going with containment (and presuming FAA lets them) they will need to have a solid public relations campaign ready to go. They'll need some sort of demo showing to the average person that the system will work. How you do that without showing all kinds of nasty things going out the outflow system is beyond me, but a simulation won't be convincing enough, IMHO.

Boeing will need a solid "investor relations campaign" as much as a public relations campaign. These technical failures with the batteries has not yet caused Boeing's stock price to drop like a rock, but it has certainly erased any short (to mid) term upside to the stock price, something that has NOT been lost on Boeing's stockholders or institutional investors. A shareholder revolt should also be on Boeing's radar screen. These same Boeing senior leaders now fail to recognize the risk of an possible Engineering strike at Boeing, in spite of all that has gone wrong with the 787.

It's not going to be pretty with the Wall Street analysts and Boeing's corner offices, for sure.

[Edited 2013-02-18 16:10:01]

Topic: RE: FAA Grounds 787, Part 10
Username: prebennorholm
Posted 2013-02-18 18:04:23 and read 23600 times.

Quoting s5daw (Reply 26):
Quoting prebennorholm (Reply 12):
The Yuasa LVP65 spec sheet, which has been linked several times in these threads, tells that energy density is 101 Wh/kg. Those 150 Wh/kg indicated by MIT is more like dreaming, or hopefully a typo.

Could it be a difference between stored useful energy and total energy?
I know that LiPo cells must not drop below certain voltage or they go into thermal runaway - indicating there is still energy in them, but we can't use it.

The Yuasa LVP65 spec sheet data are based on charging to 4.025V and discharge to 2.7V.

The 2.7V figure is rather conservative. I wouldn't mind going down to 2.5V. But you can see on the discharge charts on the spec sheet that even extrapolating down to zero volt would hardly add one single percent to the capacity. The time/voltage curve is practically vertical at 2.7V.

It is very important not to discharge below minimum voltage. Doing so will start a chemical process in the battery which permanently erodes capacity. In addition it increases internal resistance which seriously decreases its ability to deliver short duration high power bursts as for instance needed to start the APU.

It will, however, not initiate a thermal runaway. But the increased resistance will increase heat generation during charging. If you charge such a degraded cell at maximum charge rate for a good cell, then it will cause the heat sensor to cut out charging well before it has reached even its degraded capacity. Only if the heat cut off fails, could it by itself cause a thermal runaway.

If you charge it at a reasonably slow rate - say 2-3 hours to full capacity - then such a degraded cell will be as safe as a good one, but it will act as if it was a smaller cell.

In principle this low voltage degrading works the same way as aging. We probably all have at least half a dozen such age-degraded Li-Ion batteries in years old phones, shavers, powertools, laptops, iPods, iPads, iGodknowswhat and other consumer products. The producers of such products usually make charge rate well below maximum for new cells, therefore we don't notice anything until opration time becomes uncomfortably short.

Topic: RE: FAA Grounds 787, Part 10
Username: gulfstream650
Posted 2013-02-18 18:10:56 and read 23637 times.

Quoting Wolbo (Reply 54):

I'm scratching my head at this point. Who were those people? For all we know they were pulled in off the street and paid $$ for their time. They certainly did not look very interested. If they were journalists, they would be taking notes.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-18 18:20:06 and read 23611 times.

Quoting gulfstream650 (Reply 59):
Who were those people?

It might have been an internal Boeing presentation for employees. In a company that large and diverse, I expect a significant number of them have no idea about the 787's electrical architecture.

Topic: RE: FAA Grounds 787, Part 10
Username: BoeingVista
Posted 2013-02-18 20:28:15 and read 23317 times.

Quoting gulfstream650 (Reply 59):

I'm scratching my head at this point. Who were those people? For all we know they were pulled in off the street and paid $$ for their time. They certainly did not look very interested. If they were journalists, they would be taking notes.

Looks like a focus group. No questions asked or answered so just a PR fluff piece.

I don't think that events like this will help Boeing's credibility

Topic: RE: FAA Grounds 787, Part 10
Username: Part147
Posted 2013-02-18 23:40:25 and read 22970 times.

Quoting BoeingVista (Reply 61):
Looks like a focus group. No questions asked or answered so just a PR fluff piece.

I don't think that events like this will help Boeing's credibility

I plan to discuss this with aircraft engineering students later on (we've been watching these events evolve over the last few weeks)... I'l let you know what they think afterwards!

Topic: RE: FAA Grounds 787, Part 10
Username: BoeingVista
Posted 2013-02-19 00:01:43 and read 22961 times.

Quoting Part147 (Reply 62):

I plan to discuss this with aircraft engineering students later on (we've been watching these events evolve over the last few weeks)... I'l let you know what they think afterwards!
http://video.boeing.com/services/pla...0eUADvmgWcuM2F&bctid=2167891130001

There is also a 30 minutes long version..

Topic: RE: FAA Grounds 787, Part 10
Username: packsonflight
Posted 2013-02-19 00:42:40 and read 22809 times.

Quoting gulfstream650 (Reply 59):
I'm scratching my head at this point. Who were those people? For all we know they were pulled in off the street and paid $$ for their time. They certainly did not look very interested. If they were journalists, they would be taking notes.

I am a bit curious too...

Interesting that Sinnet only mentions the secondary role of the battery on the 787, starting up the APU and initial power up. He does not mention the primary role of the battery in an emergency when the battery is left to power the brakes or flight instrument.

The comparison figures shown in the slide are important. It says that the battery on the 777 is 16A but on the 787 it is 150A. That is a huge difference and makes me wonder if changing to another battery thechnology would be possible

Topic: RE: FAA Grounds 787, Part 10
Username: flood
Posted 2013-02-19 02:01:28 and read 22705 times.

NY Times: Japan Finds Swelling in APU battery of ANA aircraft involved in emergency landing:

"I do not know the exact discussion taken by the research group on the ground, but I heard that it is a slight swelling (in the auxiliary power unit battery cells). I have so far not heard that there was internal damage," Masahiro Kudo, a senior accident investigator at the JTSB said in a briefing in Tokyo.

Kudo said that two out of eight cells in the second battery unit showed some bumps and the JTSB would continue to investigate to determine whether this was irregular or not.

http://www.nytimes.com/reuters/2013/...r=rss&emc=rss&smid=tw-nytimes&_r=0

Topic: RE: FAA Grounds 787, Part 10
Username: BoeingVista
Posted 2013-02-19 03:19:10 and read 22417 times.

Quoting flood (Reply 65):
NY Times: Japan Finds Swelling in APU battery of ANA aircraft involved in emergency landing:

So this opens a new front, the next logical question is how may installed or returned 787 batteries exhibited signs of swelling

Topic: RE: FAA Grounds 787, Part 10
Username: LTC8K6
Posted 2013-02-19 05:10:52 and read 22016 times.

Finding the swelling battery cells could be very good if it gives them info on what is going on with the batteries/cells.

Topic: RE: FAA Grounds 787, Part 10
Username: par13del
Posted 2013-02-19 06:08:43 and read 21821 times.

Quoting KFLLCFII (Reply 8):
Would the combination of such a box and the Lithium-Ion battery end up weighing close to what a conventional Ni-Cad installation would be?

I think space is the primary issue in the EE bays, not weight.

Quoting rheinwaldner (Reply 13):
How to proove a containment?
IMO Boeing should build 10 of them and let burn down 10 batteries within the aircraft.

So mock up are out of the question, one must actually risk life and limb in this day or modern technology?

Quoting NAV20 (Reply 23):
I'm talking about the possibility of the authorities refusing to allow any further use of these batteries, thus forcing Boeing to spend a year or more developing, installing, and certifying new batteries straight away.

If such were to happen I would expect it to be a mandate after a temporary fix is put in place to allow a/c to fly.

Quoting NAV20 (Reply 23):
The costs of any such 'programme' would be simply colossal?

Hence my thought that the FAA in its oversight of the industry in the USA would look at such as a last resort.

Quoting gulfstream650 (Reply 49):
I really don't see how an organization such as the FAA would allow this tempory fix to suffice in order for revenue flights to proceed.

There is a saying about those who do not study history, suggest a review of the FAA, its mandate and its history.

Topic: RE: FAA Grounds 787, Part 10
Username: francoflier
Posted 2013-02-19 06:33:01 and read 21718 times.

Quoting flood (Reply 65):
Kudo said that two out of eight cells in the second battery unit showed some bumps and the JTSB would continue to investigate to determine whether this was irregular or not.

Stupid question:

Have all other installed batteries been removed from the rest of the fleet and 'autopsied'?

I'm sure the answer is in the half million posts already posted, and it seems the logical thing to do. Still...

Topic: RE: FAA Grounds 787, Part 10
Username: Antoniemey
Posted 2013-02-19 13:33:08 and read 20967 times.

Quoting gulfstream650 (Reply 49):
I understand aviation and the risks but I don't think that I would be comfortable to fly on a 787 until this issue if PROPERLY FIXED.

Then apparently you don't understand the risks... In the incidents that have occurred, there was little to no danger to the aircraft or passengers. The FAA FEARS that future failed containment COULD potentially damage an aircraft which COULD lead to POSSIBLE danger to passengers.

Personally, I'd fly on one tomorrow if I could. Even with the projected rate of catastrophic battery failure from assuming this is the "normal" failure rate going forward, you're more likely to die from pilot error or damage related to a bird strike than you are from damage due to the battery immolating itself.

Topic: RE: FAA Grounds 787, Part 10
Username: AeroWesty
Posted 2013-02-19 13:44:32 and read 20865 times.

Quoting francoflier (Reply 69):
Have all other installed batteries been removed from the rest of the fleet and 'autopsied'?

Good question, I've been wondering the same. I've not read that any other used batteries have been inspected, but I certainly hope the investigation covers in-service batteries to see if there were any dangers developing. That would seem to be a logical thing to do before allowing planes back into the air, especially if they'll be receiving a new containment unit, as speculated.

Topic: RE: FAA Grounds 787, Part 10
Username: ServantLeader
Posted 2013-02-19 13:52:18 and read 20828 times.

Quoting Antoniemey (Reply 70):
Then apparently you don't understand the risks... In the incidents that have occurred, there was little to no danger to the aircraft or passengers.

Right, and the overheating battery emitted a burning smell which forced the plane to make an emergency landing and evacuate the passengers via inflated emergency slides -- just another day on the tarmac.

Topic: RE: FAA Grounds 787, Part 10
Username: Antoniemey
Posted 2013-02-19 14:00:32 and read 20768 times.

Quoting ServantLeader (Reply 72):
Right, and the overheating battery emitted a burning smell which forced the plane to make an emergency landing and evacuate the passengers via inflated emergency slides -- just another day on the tarmac.

That is NOT what I said.

Topic: RE: FAA Grounds 787, Part 10
Username: RickNRoll
Posted 2013-02-19 15:12:28 and read 20543 times.

Quoting Antoniemey (Reply 70):
Then apparently you don't understand the risks... In the incidents that have occurred, there was little to no danger to the aircraft or passengers. The FAA FEARS that future failed containment COULD potentially damage an aircraft which COULD lead to POSSIBLE danger to passengers.

Which is a serious enough issue to ground the fleet indefinitely.

Topic: RE: FAA Grounds 787, Part 10
Username: XT6Wagon
Posted 2013-02-19 17:09:48 and read 20233 times.

Quoting Antoniemey (Reply 70):
Even with the projected rate of catastrophic battery failure from assuming this is the "normal" failure rate going forward, you're more likely to die from pilot error or damage related to a bird strike than you are from damage due to the battery immolating itself.

More likely to die in your shower tonight than die flying around the world in a 787 (with fuel stops).
More likely to get hit by a drunk driver. (even in your own home)
More likely to get murdered by someone on PCP
More likely to *.*

People are very bad at risk analysis. We have 10 threads proving it.

Quoting RickNRoll (Reply 74):
Which is a serious enough issue to ground the fleet indefinitely.

There is a plane model that suffered engine power loss on both engines on multiple airframes in flight. Atleast one instance caused injuries. It was grounded for 0 days. Want to guess which plane this was?

Topic: RE: FAA Grounds 787, Part 10
Username: prebennorholm
Posted 2013-02-19 17:14:44 and read 20228 times.

Quoting packsonflight (Reply 64):
The comparison figures shown in the slide are important. It says that the battery on the 777 is 16A but on the 787 it is 150A.

Those figures are "current provided for airplane power-up". They do not tell anything about the power capabilities of those batteries.

From the 787 battery Yuasa LVP65 spec sheet we know that the discharge rate limit is 325A.

I haven't seen a spec sheet for the 777 batteries. But a 107lbs 20 cells NiCad battery will certainly have no problem delivering amps way up in the hundreds.

The difference - 16A vs. 150A - tells about different airplane achitecture and nothing else. 16A will for instance no way start an APU, even on the smallest airliner. 16A will run some of the avionics, and no more.

We know the capabilities of each battery technology. A NiCad battery for the 787 with similar capacity will have to be roughly 2½ times heavier, so more like 160 lbs instead of the 107 lbs on the 777.

Generally NiCad batteries are quite a lot more forgiving at extreme discharge rates. So a NiCad battery scaled to 787 capacity would likely be limited to somewhere between 500 and 1000A - that's roughly similar to your lead-acid car battery, but at half the voltage.

Topic: RE: FAA Grounds 787, Part 10
Username: DTW2HYD
Posted 2013-02-19 18:02:50 and read 20401 times.

Quoting stasisLAX (Reply 57):
Boeing will need a solid "investor relations campaign" as much as a public relations campaign.

In summary they need to wine and dine 4 Network + 3 Cable so called "Aviation Experts". Give some exclusive access to couple of batteries and some lab. Take them to Chicago,Seattle,Paris and Japan. No need to tell them anything (quote ongoing NTSB investigation), Boeing's Media/PR/Investor problem is solved.

Topic: RE: FAA Grounds 787, Part 10
Username: SEA
Posted 2013-02-19 19:32:25 and read 20303 times.

It appears as if JL have removed their titles from the 788 at BOS.

https://twitter.com/martysg/status/304063194480140289

Topic: RE: FAA Grounds 787, Part 10
Username: PHX787
Posted 2013-02-19 19:41:50 and read 20211 times.

Quoting SEA (Reply 78):
It appears as if JL have removed their titles from the 788 at BOS.

This is surprising! Is the window covered up too?

Topic: RE: FAA Grounds 787, Part 10
Username: RickNRoll
Posted 2013-02-19 20:15:29 and read 20092 times.

Quoting SEA (Reply 78):
It appears as if JL have removed their titles from the 788 at BOS.

Are they going to RMA it?

Topic: RE: FAA Grounds 787, Part 10
Username: LTC8K6
Posted 2013-02-19 20:37:08 and read 20015 times.

Maybe they are going to test fly it?

Topic: RE: FAA Grounds 787, Part 10
Username: rheinwaldner
Posted 2013-02-19 21:28:32 and read 19909 times.

Quoting Stitch (Reply 45):
Special Condition 2 appears to have been violated in terms of a self-sustaining increase in temperature, but newer cathode chemistries have been designed to address that so changing the cathode chemistry to one of those new formulas should bring the battery back into compliance with this condition.

Bingo. So you think that just making a new containment and keeping this requirement broken will be enough to bring the 787 in the air again?

Nonconformance with this requirement went undetected the first time which has led to this very uncomfortable situation today (where the FAA is accused to have certified in blind flight and people are wondering what else they did not notice).

But now we know that this battery violates this requirement. And you honestly believe that just strengthening the cage around it will be good enough to let something fly, that should never have been certified in the first place? This would be like mandating that just any other technology or solution, that is known to have failed certification criteria prior EIS, should be allowed to be fixed after EIS.

Quoting Stitch (Reply 53):
This is why I could see the FAA not forcing Boeing to park the plane until the new battery is ready provided they have a containment system guaranteed proven to protect against a major fire and/or electrolyte leak with the current battery to return the 787 to service in the interim.

There is no interim safety. The safety is guaranteed by meeting the hard requirements. So it is not acceptable to let the plane fly with technology that could break key requirements during every flight.

Quoting Stitch (Reply 53):
Passenger safety is not compromised during the development of the new battery and Boeing and airlines are able to return to operation.

There is no requirement that is actually just waste and not really needed for uncompromised safety. So removing required guards and safety levels does compromise the safety. Always. Even if it is interim.

Quoting par13del (Reply 68):
Quoting rheinwaldner (Reply 13):
How to proove a containment?
IMO Boeing should build 10 of them and let burn down 10 batteries within the aircraft.

So mock up are out of the question, one must actually risk life and limb in this day or modern technology?

No, no, these "burning batteries" tests should be done on the ground. Stitch proposed the same test inflight in order to create some PR effect that should restore public confidence. The hype, that would be created by doing that, would on the other hand help people to remember much longer that "there was something".

Quoting prebennorholm (Reply 58):
If you charge such a degraded cell at maximum charge rate for a good cell, then it will cause the heat sensor to cut out charging well before it has reached even its degraded capacity.

As charging is done with much less current. From the data I gathered somewhere it is charged quite conservatively with about 1C. So this defect would not necessarily bite the next time the battery is charged, but the next time it is discharged with 5C to 10C.

Quoting Antoniemey (Reply 70):
Quoting gulfstream650 (Reply 49):
I understand aviation and the risks but I don't think that I would be comfortable to fly on a 787 until this issue if PROPERLY FIXED.

Then apparently you don't understand the risks... In the incidents that have occurred, there was little to no danger to the aircraft or passengers. The FAA FEARS that future failed containment COULD potentially damage an aircraft which COULD lead to POSSIBLE danger to passengers.

Gulfstream650 did probably fear the same as the FAA to feel uncomfortable. I reworded how I would understand it:
Gulfstream650 feels uncomfortable that future failed containment COULD potentially damage an aircraft which COULD lead to POSSIBLE danger to passengers of an aircraft where he sits in. And yes, that would be a real risk if broken requirements stay unfixed for a while.

Topic: RE: FAA Grounds 787, Part 10
Username: gemuser
Posted 2013-02-19 21:53:05 and read 19793 times.

Quoting rheinwaldner (Reply 82):
And you honestly believe that just strengthening the cage around it will be good enough to let something fly,

Yes! It's called a wavier or concession against the requirement, a standard procedure that's been used time & time again. I see no reason (publicly available) why the FAA would not approve it until a more permanent fix can be developed, provided the interim measures do not compromise safety (which sounds possible given what is being reported) in the opinion of the certifying authority. It's been done before and will be done again in the future. It's how the system works and how its worked for the last 70 years.

Gemuser

Topic: RE: FAA Grounds 787, Part 10
Username: BoeingVista
Posted 2013-02-19 22:53:10 and read 19713 times.

Quoting RickNRoll (Reply 80):

Are they going to RMA it?

Looks like they are going to DHL it back to Seattle by road freight as they can't air freight the batteries  

Topic: RE: FAA Grounds 787, Part 10
Username: rikkus67
Posted 2013-02-19 23:35:51 and read 19571 times.

http://www.upworthy.com/see-the-scie...e-world-or-at-least-your-battery-l

I found this brief scientific blurb of an alternate energy source quite interesting (Graphene Superconductor)...anyone want to pass this along?

Topic: RE: FAA Grounds 787, Part 10
Username: RobK
Posted 2013-02-19 23:52:49 and read 19521 times.

Quoting gulfstream650 (Reply 49):
I really don't see how an organization such as the FAA would allow this tempory fix to suffice in order for revenue flights to proceed.It just simply isn't an acceptable solution in this day and age and you can bet that if there is indeed another incident takes place you can be sure that the media will have a field day and Boeing will suffer. I understand aviation and the risks but I don't think that I would be comfortable to fly on a 787 until this issue if PROPERLY FIXED. The proposed temporary fix if nothing other than glorified bush mechanics.If the plane is allowed to fly as Boeing proposes, it will be nothing other than the result of a good 'ol USA back room political play.Not acceptable.

Those are pretty much my thoughts on the situation as well. The FAA are still clearing the egg from their faces after the first round of blazing batteries; I don't see them willing to risk this happening a second time by stating it's okay for the planes to catch fire so long as they have a metal box round it. Add in the fact that the cause still isn't known AND they've discovered a bunch of bulging batteries ready to explode on other 787s... I just don't see how they can possibly certify them for flight.

Personally I think they should be kept grounded for however long it takes to get some safe batteries installed, such as the NiCads. However what I think will happen is either one of two things :

a. the FAA says "no" and they all stay grounded for the next ~ 12 months while a stable battery set-up is developed and certified.

b. some brown envelopes change hands with the FAA and they're back in service by summer complete with the metal box bodge. I foresee within a few months of this happening one of them will catch fire, the media outlets all over the world will have a frenzy, the FAA will ground it again and they won't fly until a new battery system is developed.

Topic: RE: FAA Grounds 787, Part 10
Username: rheinwaldner
Posted 2013-02-20 01:30:23 and read 19251 times.

Quoting gemuser (Reply 83):
I see no reason (publicly available) why the FAA would not approve it until a more permanent fix can be developed, provided the interim measures do not compromise safety (which sounds possible given what is being reported) in the opinion of the certifying authority.

Please stop joking.
You are making some wild claims and owe us some evidence that knowingly unmet certification requirements have ever been waivered to be resolved at a later point, in parallel while the plane already is being operated.

Topic: RE: FAA Grounds 787, Part 10
Username: freakyrat
Posted 2013-02-20 03:23:33 and read 19009 times.

Boeing seems to have found a way to fix the battery problems and hopes flights of the Dreamliner can resume in April.

http://www.foxbusiness.com/news/2013...my+%28Internal+-+Economy+-+Text%29

Topic: RE: FAA Grounds 787, Part 10
Username: aviaponcho
Posted 2013-02-20 03:47:10 and read 18910 times.

Did you get this one

http://www.npr.org/templates/story/story.php?storyId=172470522

Miswiring between APU / Main batteries...
What can we think of that ?

Topic: RE: FAA Grounds 787, Part 10
Username: gemuser
Posted 2013-02-20 04:10:12 and read 18828 times.

Quoting rheinwaldner (Reply 87):
You are making some wild claims and owe us some evidence that knowingly unmet certification requirements have ever been waivered to be resolved at a later point, in parallel while the plane already is being operated.

Please stop being so emotional!
It is normal practice, I use to process them.
The Boeing 787-8 has a "before further flight" Airworthiness Directive issued on it. That directive contains the conditions for satisfying the directive. Those conditions are:

Quote:
This AD requires modification of the battery system, or other actions, in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA.

See:
AD.nsf/0/8a1a8dc3135b60dd86257af60004cf4a/$FILE/2013-02-51_Emergency.pdf" target="_blank">http://rgl.faa.gov/Regulatory_and_Gu...f4a/$FILE/2013-02-51_Emergency.pdf

It is totally within the power of said manager to approve/disapprove any proposal Boeing may submit. He already has the power to issue a "waiver" to the certification requirements, including the Special Requirements, if he thinks it justified. He obviously won't approve any proposal if it decreases safety to an "unacceptable" level. "Unacceptable" being determined by said Manager in accordance with all the regulations, rules, procedures & practices already in place.
I think it is VERY likely, on the publicly available information, that said Manager WILL approve a beefed up containment box with external venting. Of course what is NOT publicly available may change this.
There is NOT and never has been a guarantee of complete safety in aviation, it is by its nature, dangerous. The current system, put in place from 1944 has delivered an increasing level of safety ever since. Its not perfect, but it is effective. The fact that the last airline "before further flight" AD was issued in the late 1970s, as discussed in these threads, is a testament to this.
There does not appear to be a consolidated list of previous waivers on the FAA web site (at least I couldn't find it) but there are a "lot" of references to them. I don't have the time to find any specific ones, but they are there somewhere. Maybe you would like to educate yourself by preparing a summary of those waivers issued against certification requirements over the last (say) 40 years. I think you would be very surprised by the results.

Gemuser

Topic: RE: FAA Grounds 787, Part 10
Username: NAV20
Posted 2013-02-20 04:27:03 and read 18761 times.

Something 'new,' I suspect. I'm arguably quite good with words, but just about illiterate with physics/electricity - but this story appears strongly to suggest that the recent B787 problems may have been caused by wiring errors:-

"TOKYO (AP) — A probe into the overheating of a lithium ion battery in an All Nippon Airways Boeing 787 found it was improperly wired, Japan's Transport Ministry said Wednesday.

"The Transport Safety Board said in a report that the battery of the aircraft's auxiliary power unit was incorrectly connected to the main battery that overheated, although a protective valve would have prevented power from the APU from doing damage.

"Flickering of the plane's tail and wing lights after it landed and the fact the main battery was switched off led the investigators to conclude there was an abnormal current traveling from the APU due to miswiring.

"The agency said that more analysis was needed to determine what caused the main battery to overheat and emit the smoke that prompted the Jan. 16 emergency landing of the ANA domestic flight and the worldwide grounding of Boeing 787 jets. They said they are consulting Boeing about the issue."


http://www.npr.org/templates/story/story.php?storyId=172470522

Just maybe there are still some prospects of a 'happy ending' to this huge mess?

Topic: RE: FAA Grounds 787, Part 10
Username: robffm2
Posted 2013-02-20 05:31:55 and read 18556 times.

Meanwhile the NYT reports that Boeing is looking for additional parking lots.

http://www.nytimes.com/2013/02/20/re...=1361366994-rwnEXFGloP0a4PZiDzzEbg

Topic: RE: FAA Grounds 787, Part 10
Username: jbcarioca
Posted 2013-02-20 06:14:48 and read 18350 times.

Recent events do indicate that there is a quality control problem with the B787 electrical system. That may be in manufacture, maintenance or both. Incorrect connections have played a role in more than one of these events.

So, Boeing made much of the design of B787 systems to select fittings, connectors, lengths colors and design to effectively preclude faulty connections. However, some people somewhere have successfully overridden these design elements and instructions.

It is logical to assume that these connections and others will be reviewed and corrected as needed to reduce the risk of error.

The redesign of the batteries to ensure better ventilation and overheating risk is another obvious requirement.

Boeing promised better containment and expulsion that is also needed. A cynic might note that they promised they and done that already in the original certification conditions and further attested that there was only a one in ten million chance of a leak anyway. Forgive me for a slight dose of cynicism regarding the Boeing outsourcing process that let this happen without extensive review (according to nameless Boeing engineers anyway).

Will all these things resolve the problems? Are the root causes identified? Who knows?

Topic: RE: FAA Grounds 787, Part 10
Username: rheinwaldner
Posted 2013-02-20 06:56:39 and read 18109 times.

Quoting gemuser (Reply 90):
I think it is VERY likely, on the publicly available information, that said Manager WILL approve a beefed up containment box with external venting.

From which publicly available information would you derive that?

Quoting gemuser (Reply 90):
There does not appear to be a consolidated list of previous waivers on the FAA web site (at least I couldn't find it) but there are a "lot" of references to them.

So that would support my view (no evidence of the opposite). Look, we need examples to find out whether this case bares similarities with something that happened earlier.

For comparisons you probably need a case like the DC-10 grounding. And I bet, if you add the remaining characteristics of the 787-case, you won't find any comparable case that has happened before. A case, where:
- There was a valid requirement (which means that it was not the fault of the requirement)
- The solution was certified under the wrong assumption, that it would meed the requirement (which means that there was a failure of the certifying authority)
- Multiple real world events proved, that there was a real gap between solution and requirement (which means that there is a flaw in the design)
- There was a serious threat (burning equipment that was not intended to burn), a serious impact and a serious conclusion (grounding).

So I would say the challenge is still on your side, to provide evidence that half baked solutions have ever been given a waiver under such conditions. I bet there is no such case and the 787 will also not be the first. All based on publicly available information.

I mean there are serious reputation risks for the FAA if they get this one wrong. And the FAA's reputation would probably be the smallest problem if real world events will develop once more in the wrong direction...

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-20 08:25:39 and read 17830 times.

Quoting Stitch (Reply 45):
Special Condition 2 appears to have been violated in terms of a self-sustaining increase in temperature, but newer cathode chemistries have been designed to address that so changing the cathode chemistry to one of those new formulas should bring the battery back into compliance with this condition.
Quoting rheinwaldner (Reply 82):
Bingo. So you think that just making a new containment and keeping this requirement broken will be enough to bring the 787 in the air again?

  

  



Quoting NAV20 (Reply 91):
Something 'new,' I suspect. I'm arguably quite good with words, but just about illiterate with physics/electricity - but this story appears strongly to suggest that the recent B787 problems may have been caused by wiring errors:-

UA found the same on one of their 787s when they performed inspections after the diversion to MSY.

  

Topic: RE: FAA Grounds 787, Part 10
Username: CF-CPI
Posted 2013-02-20 08:27:17 and read 17813 times.

Quoting jbcarioca (Reply 93):
Recent events do indicate that there is a quality control problem with the B787 electrical system.

Now that mis-wiring has been identified on one of the 'problem' aircraft, I am curious (as I am sure others are) as to how widespread it is across the entire 787 fleet. Some aircraft reported premature battery replacement, and I would be curious to know if there is any correlation between that issue and mis-wiring. I suppose it's possible that the mis-wiring is not directly causal to the battery overheat, but just another anomaly in the construction of the aircraft that needs addressing. I hope we'll get answers to these questions.

Topic: RE: FAA Grounds 787, Part 10
Username: starrion
Posted 2013-02-20 09:32:11 and read 17450 times.

So if they fix what is probably some form of sneak circuit in the wiring, gap the Li-ion cells so they don't cascade into thermal runaway, and strengthen and vent the containment, then we should be at a point where the batteries wouldn't be melting down.

That's probably the first good news since this sorry incident began.

Let's hope they made some progress on the generator issue and the other squawks they got in the intervening time.

Topic: RE: FAA Grounds 787, Part 10
Username: Kaiarahi
Posted 2013-02-20 10:13:29 and read 17295 times.

Quoting rheinwaldner (Reply 94):
So I would say the challenge is still on your side, to provide evidence that half baked solutions have ever been given a waiver under such conditions.

TWA800. The interim solution was to fly at all times with a specified minimum amount of fuel in the centre wing tank to reduce the risk of vapour build-up, while the NTSB continued its investigation into ignition sources. The design/certification issue was i) placement of the air con packs under the tank, allowing heat to be transferred and ii) a design assumption that vapour build-up could never be completely eliminated as a risk, so as a certification condition there must be no source of potential ignition in the tanks (which proved not to be the case). Unlike the 787, there had been 3 hull losses and 300 fatalities.

Topic: RE: FAA Grounds 787, Part 10
Username: Boeing717200
Posted 2013-02-20 11:05:05 and read 17105 times.

Glimmer of hope?

http://finance.yahoo.com/news/boeing...-dreamliner-battery-172708729.html

Topic: RE: FAA Grounds 787, Part 10
Username: sweair
Posted 2013-02-20 11:53:13 and read 16798 times.

I don't buy any anonymous info, the only info I trust is official from Boeing, NTSB and FAA, the rest is best taken with a huge amount of salt.

Remember there are always people out to make a buck when there are big stories. The Internet age makes people restless for info and news. A problem like this is not solved over night, if B did not know about it before this all happened that is. Maybe they had a study for a long time, who knows really.

Topic: RE: FAA Grounds 787, Part 10
Username: rheinwaldner
Posted 2013-02-20 12:00:34 and read 16755 times.

Quoting Kaiarahi (Reply 98):
TWA800

Good point, but IMO TWA800 was not a comparable case:

- In case of TWA800 the certification requirements AND the design have been validated by decade long uneventful operation (regarding the probable cause of that accident).

- So it was clear from the start that potentially new, more stringent requirements eventually would be the result of the investigations. But both, the initial requirements and the design were still sound. The nature of the bug was known to be extremely rare. The design did e.g. not violate older and known requirements.

All this points differ in case of the 787. So this was not a comparable case, where unfulfilled requirements were waivered to stay in place unadressed, just to continue operation.

Topic: RE: FAA Grounds 787, Part 10
Username: Kaiarahi
Posted 2013-02-20 12:11:04 and read 16932 times.

Quoting rheinwaldner (Reply 101):

Agreed, it's not completely comparable. But it did involve a secondary fix (minimum fuel / battery containment) while the root cause (ignition source / thermal runaway) was pursued. And the NTSB was not happy.

Topic: RE: FAA Grounds 787, Part 10
Username: Wisdom
Posted 2013-02-20 12:24:57 and read 16898 times.

If the miswiring is confirmed, it would acknowledge my theory that the current fed to the batteries by the wild frequency generators was "impure", causing the batteries to suffer from irregular charging parameters and heat up. This would also confirm my theory that the batteries were not in the wrong, but everything around it.

I was suspecting the engine generators, but with the APU it makes more sense.
The NH B787 was barely in the air, the APU would have been running on the ground.

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-20 12:25:56 and read 16900 times.

Quoting Kaiarahi (Reply 98):
Quoting rheinwaldner (Reply 94):So I would say the challenge is still on your side, to provide evidence that half baked solutions have ever been given a waiver under such conditions.
Quoting Kaiarahi (Reply 98):
TWA800. The interim solution was to fly at all times with a specified minimum amount of fuel in the centre wing tank to reduce the risk of vapour build-up, while the NTSB continued its investigation into ignition sources.

Filling the center tank to a minimum level was not a half baked idea and decreased even farther the already extremely remote chance of another failure. The fleet hours for those three incidents was tens of thousands of times more than the 50 787's in service. In this case the FAA didn't wait for a loss of life incident to start the process as they did with

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-20 12:31:34 and read 16833 times.

Quoting Kaiarahi (Reply 102):
And the NTSB was not happy.

Is the NTSB ever happy?

Topic: RE: FAA Grounds 787, Part 10
Username: LTC8K6
Posted 2013-02-20 12:46:16 and read 16745 times.

The miswiring article seems to be saying that while there was a wiring problem, it didn't cause the battery problem.

Topic: RE: FAA Grounds 787, Part 10
Username: gemuser
Posted 2013-02-20 12:50:59 and read 16715 times.

Quoting rheinwaldner (Reply 94):
From which publicly available information would you derive that?

Up thread & linked articles.

Quoting rheinwaldner (Reply 94):
So that would support my view (no evidence of the opposite). Look, we need examples to find out whether this case bares similarities with something that happened earlier.

No it does not! It simply means that it would require too much research to prove it to you, who obviously wishes to ignore reality.
I worked inside the airworthiness system for ten years, waivers/concessions happen every day, for all sorts of reasons and against all sort of requirements, it just that the general public just never hears about them. In ALL cases, that I saw, the professionals involved made sure that the level of safety was appropriate for the risk (if any) involved.

Gemuser

Topic: RE: FAA Grounds 787, Part 10
Username: Kaiarahi
Posted 2013-02-20 13:02:32 and read 16626 times.

Quoting 7BOEING7 (Reply 104):
Filling the center tank to a minimum level was not a half baked idea

Agreed - leaving aside the language of the post I was responding to, I was looking for an example where the FAA was satisfied (at least on an interim basis) with a fault tree approach that did not address the design condition (no sources of potential ignition), but rather addressed the probability of a design assumption (flammable vapour accumulation). I don't think containment is half-baked either, but as you rightly point out, the incidence of battery runaway is (at this point anyway) way higher than the incidence of exploding fuel tanks.

Topic: RE: FAA Grounds 787, Part 10
Username: AeroWesty
Posted 2013-02-20 13:33:11 and read 16438 times.

The question of where are the grounded 787s parked comes up from time to time. From a link in an article I was reading, it appears they're in 17 airports around the world:

Grounded and Stranded: Where in the World are the Delivered Dreamliners?

Topic: RE: FAA Grounds 787, Part 10
Username: ServantLeader
Posted 2013-02-20 13:59:19 and read 16316 times.

Quoting gemuser (Reply 107):
I worked inside the airworthiness system for ten years, waivers/concessions happen every day, for all sorts of reasons and against all sort of requirements, it just that the general public just never hears about them. In ALL cases, that I saw, the professionals involved made sure that the level of safety was appropriate for the risk (if any) involved.

Ah, a person in the know -- your opinion please on this supposition:

The 787 situation is obviously not an everyday rubber stamper -- it has become an international saga, and for some such as Boeing and the FAA, an international embarrassment -- since public perception is that the FAA was lax / hands-off in certifying the Li-ion battery system, and therefore complicit in the unfolding debacle, that they must now save face by showing that they are an impartial tough-minded regulatory agency looking out for the public's saftey first and foremost, immune to the ever present pressure to move things along in the name of corpoarte profits / shareholder wealth -- which means that they will likely reject temporary workarounds and/or any fix that smells less than 1000% safe -- which means Boeing's better fire-proof / explosion-proof box is a non-starter -- which means Beoing will be forced to go back to the drawing board and do a complete redesign using a proven safe technology such as NiCad -- which means a whole new cerification process -- which means 2013 is a no-fly zone for the 787.

Topic: RE: FAA Grounds 787, Part 10
Username: strfyr51
Posted 2013-02-20 14:20:08 and read 16199 times.

Here's Hoping that Boeing's "batteries" are in place, But I wonder when the new Battery Cases will be available with the Mods Installed?? Right now 100+ batteries will be needed as a minimum and that's going to take Time in itself with shipping. We just got all of our airplanes back on US soil and We have LOT's 787 at ORD. I know they'll be glad to hear this news.

Boeing Co has found a way to fix battery problems on its grounded 787 Dreamliner jets that involves increasing the space between the lithium ion battery cells, a source familiar with the U.S. company's plans told Reuters.

"The gaps between cells will be bigger. I think that's why there was overheating," said the source, who declined to be identified because the plans are private.

A spokeswoman for the U.S. National Transportation Safety Board declined comment on the Reuters report or any Boeing plan to return the 787s to the air.

"The decisions to return the airplane to flight will be made by the FAA and only after Boeing has demonstrated to them that the solution is adequate," Kelly Nantel said. "We continue to investigate the cause of the short circuiting."

A spokeswoman from the U.S. Federal Aviation Administration declined to comment. Boeing declined comment on details of any battery fix it may be considering.

Boeing is set to meet the FAA on Friday to propose measures to address the battery issue.

Topic: RE: FAA Grounds 787, Part 10
Username: PanAmPaul
Posted 2013-02-20 15:12:55 and read 16004 times.

Not sure if this is covered in the past 112 posts in this thread (I read as many as I could) but Boeing's top commercial airplane execs are going to meet with top FAA officials later this week and present a 10-part plan to get the Dreamliner back flying again.

Japanese officials apparenly found improper wiring in the ANA airplane that had the emergecny landing on Jan. 16. (Hard to imagine this was more than one month ago).

Hopefully the timing will be right based on the findings coming out of Japan WRT the meeting with the FAA.

Boeing to Propose Dreamliner Battery Fixes, Regulators Find Improper Wiring in ANA Aircraft

"Japanese regulators announced they believe they figured out part of the puzzle that has kept Boeing’s 787 Dreamliner aircraft grounded since January 16. The country’s Transport Ministry said that the battery had been improperly wired on Wednesday, as Boeing planned to begin the process of getting federal regulators to approve temporary battery fixes that will allow the Dreamliner to fly on Wednesday...."

Topic: RE: FAA Grounds 787, Part 10
Username: cornutt
Posted 2013-02-20 16:30:24 and read 15734 times.

Quoting 7BOEING7 (Reply 105):
Is the NTSB ever happy?

They're not. But that's in their job description.

Topic: RE: FAA Grounds 787, Part 10
Username: DTW2HYD
Posted 2013-02-20 16:49:46 and read 15682 times.

Quoting ServantLeader (Reply 110):
The 787 situation is obviously not an everyday rubber stamper -- it has become an international saga, and for some such as Boeing and the FAA, an international embarrassment -- since public perception is that the FAA was lax / hands-off in certifying the Li-ion battery system, and therefore complicit in the unfolding debacle, that they must now save face by showing that they are an impartial tough-minded regulatory agency looking out for the public's saftey first and foremost, immune to the ever present pressure to move things along in the name of corpoarte profits / shareholder wealth -- which means that they will likely reject temporary workarounds and/or any fix that smells less than 1000% safe -- which means Boeing's better fire-proof / explosion-proof box is a non-starter -- which means Beoing will be forced to go back to the drawing board and do a complete redesign using a proven safe technology such as NiCad -- which means a whole new cerification process -- which means 2013 is a no-fly zone for the 787.

FAA is no less or more lax with 787 battery than any other certification they do every day. No doubt this issue has high visibility and they have to be diligent. If Li-on is so harmful, what about 2-3 batteries in electronic devices carried on person by each passenger. Any one of those 400 to 600 batteries can catch fire. Should FAA ban any device with Li-on both from checked and carry-on.

Topic: RE: FAA Grounds 787, Part 10
Username: prebennorholm
Posted 2013-02-20 17:02:09 and read 15667 times.

Technically I do not doubt that the temporary fix is okay. I shouldn't wonder if this fix is mostly identical to Airbus' original design for the A350. At least Reuters reported a month ago that A had developed a one-way valve to the battery container and a battery-goo-proof outflow valve.

But this issue has become a lot more complicated than just making sure to avoid accidents, including injury to people on the evacuation slides.

First of all I understand ServantLeader in reply #110 where he indicates why the FAA might be reluctant to issue a waiver. But let us just assume for a minute that they do issue a waiver, and that the 787 flies again in April or May with the temporary fix:

The FAA has grounded all 787s on US register (the United 787s). All other relevant CAAs followed (if not leading, the Japanese).

If the FAA issues the waiver, will all relevant CAAs automatically follow on lifting the grounding and copy that waiver?

What if airlines around the world write in their adverts: "We operate only Li-Ion-free planes", and put streamers on the planes: "Li-Ion free plane"?

If we assume the permanent fix to be available at the end of this year: Then this year Boeing will deliver roughly 75 new planes with the temporary fix only - those produced this year and those finishing rework. Will the airlines accept them? All of them? Some of them? None of them?

A few hundred "old" batteries will be needed for the 2013 production planes plus for tests, replacements and spares. Are they available today? If not, will Yuasa produce them? If I was Yuasa CEO, then I would maybe already have closed down production in order to achieve minimum addition mudslinging on the Yuasa brand, and because the LVP65 cell sees its end of market potential. That might violate a contract with Boeing, but again, I as Yuasa CEO would maybe rather risk to pay a $1 million compensation to Boeing when the court has spoken in five years time.

This is a really unfortunate situation with a lot of if's.

Topic: RE: FAA Grounds 787, Part 10
Username: gemuser
Posted 2013-02-20 18:08:43 and read 15444 times.

Quoting ServantLeader (Reply 110):
The 787 situation is obviously not an everyday rubber stamper -- it has become an international saga, and for some such as Boeing and the FAA, an international embarrassment -- since public perception is that the FAA was lax / hands-off in certifying the Li-ion battery system, and therefore complicit in the unfolding debacle, that they must now save face by showing that they are an impartial tough-minded regulatory agency looking out for the public's saftey first and foremost, immune to the ever present pressure to move things along in the name of corpoarte profits / shareholder wealth -- which means that they will likely reject temporary workarounds and/or any fix that smells less than 1000% safe -- which means Boeing's better fire-proof / explosion-proof box is a non-starter -- which means Beoing will be forced to go back to the drawing board and do a complete redesign using a proven safe technology such as NiCad -- which means a whole new cerification process -- which means 2013 is a no-fly zone for the 787

IMHO totally wrong. I assume that the Manager Seattle Aircraft Certification Office is a professional engineer, he/she will ensure that ANY solution complies with all regulations etc OR that there is an appropriate, solid safety case for any waivers needed.

He/she will not care about the political spin. His/her boss may very well do so, but will be constrained by Boeing, because Boeing will know that their solution complies with all requirements, even if a waiver is required. If the Manager Seattle ACO does not approve the repair scheme for political reasons the FAA will be in Federal court very quickly. Or put another way, public relations is NOT a problem for the Manager ACO, its a problem for the PR & political people.
In short the political & PR types in the FAA/DOT/Congress will not be able to disregard the professional expertise of the Seattle ACO (presumably the most experienced ACO on the planet.

Gemuser

Topic: RE: FAA Grounds 787, Part 10
Username: gemuser
Posted 2013-02-20 18:12:03 and read 15436 times.

Quoting prebennorholm (Reply 115):
If the FAA issues the waiver, will all relevant CAAs automatically follow on lifting the grounding and copy that waiver?
IF they are convinced that that the waiver is technically sound, I would think so and I really really doubt that Boeing, the Seattle ACO or the FAA in general would issue one if their peers, especially EASA & the Japanese authority, don't agree.

Gemuser

[Edited 2013-02-20 18:13:05]

Topic: RE: FAA Grounds 787, Part 10
Username: kanban
Posted 2013-02-20 18:36:43 and read 15354 times.

Quoting ServantLeader (Reply 110):
The 787 situation is obviously not an everyday rubber stamper -- it has become an international saga, and for some such as Boeing and the FAA, an international embarrassment -- since public perception is that the FAA was lax / hands-off in certifying the Li-ion battery system, and therefore complicit in the unfolding debacle, that they must now save face by showing that they are an impartial tough-minded regulatory agency looking out for the public's saftey first and foremost, immune to the ever present pressure to move things along in the name of corpoarte profits / shareholder wealth -- which means that they will likely reject temporary workarounds and/or any fix that smells less than 1000% safe -- which means Boeing's better fire-proof / explosion-proof box is a non-starter -- which means Beoing will be forced to go back to the drawing board and do a complete redesign using a proven safe technology such as NiCad -- which means a whole new cerification process -- which means 2013 is a no-fly zone for the 787.

I'm confused as to whether you're trying to add to the knowledge base or argue points that most of us are content to wait and see what the FAA decides. The attempts to fuel a flame fest do nobody any good and rash statements of corporate and agency incompetence are just noise of opinionated outsiders wanting a soapbox.

Topic: RE: FAA Grounds 787, Part 10
Username: airtechy
Posted 2013-02-20 18:43:46 and read 15354 times.

I'm not sure I understand the timing. At the time the batteries caught on "fire", I would think that neither had any current draw. One was in the air and the other parked on the ground....I assume hooked to ground power at the gate. At most I would think they were being charged at the time.

It would seem that charging is more conducive to "fires" than high current discharging.

Topic: RE: FAA Grounds 787, Part 10
Username: hOmsar
Posted 2013-02-20 19:42:43 and read 15223 times.

Quoting prebennorholm (Reply 115):
What if airlines around the world write in their adverts: "We operate only Li-Ion-free planes", and put streamers on the planes: "Li-Ion free plane"?

Virgin Atlantic's new slogan?

"No Li-Ion 4 No Fire"

Topic: RE: FAA Grounds 787, Part 10
Username: ltbewr
Posted 2013-02-20 20:30:51 and read 15106 times.

I wonder how insurers for airlines, leasing companies, Boeing and component makers will react if a temp fix is done to the 787's battery systems. They may charge higher premiums to recognize the higher potential risks from the battery-electrical issues until a permanent fix is done. That could slightly hurt the economics of the 787, but the premiums must be high enough to cover for the potential risks if a major failure in flight.

I am concerned with the FAA in all this. It is a Federal Government agency, mandated to assure aircraft safety but is also subject to politcal pressures. The FAA could be very much affected with the potential sequester/mandated Federal government budget cuts that could reduce it's ability and extend the time for their approval of any temp or permanent fix. They may also be under pressure from key politicians of both parties due to the importance of Boeing as one our biggest export manufacturers, providing 1000's of top paying jobs just for the 787, to rush approval of temp or permanent changes. They also don't want blood on their hands if there is a major crash with a loss of life from another battery-electrical system failure. It sets up huge pressure to do the right thing but not be so particuar to hurt Boeing.

Topic: RE: FAA Grounds 787, Part 10
Username: stasisLAX
Posted 2013-02-20 21:16:55 and read 15104 times.

Boeing could have the 787 back into the air within 2 months, according to this New York Times article from today (2/20/13). Special insulation (possibly ceramic) will to used to better contain the batteries according to the article. "Concerned about fires with smaller lithium-ion batteries in cellphones and laptops, the agency (FAA) placed special conditions on Boeing’s use of the batteries that required containment and venting measures that have proved inadequate" to directly quote the article.

This quote sounds rather damning to both the FAA and Boeing.... but let's all hope that there's truly a near-term "fix" coming from Boeing.

Source: http://www.nytimes.com/2013/02/21/bu...ery-fixes-to-faa.html?ref=business

Topic: RE: FAA Grounds 787, Part 10
Username: rcair1
Posted 2013-02-20 22:11:45 and read 14902 times.

Quoting prebennorholm (Reply 115):
(if not leading, the Japanese).

The Japanese aviation authority did not lead the FAA. No CAA lead the FAA. Some Airlines (ANA and JAL) chose, voluntarily, to stop flying the 787 before the FAA AD.

Quoting prebennorholm (Reply 115):
What if airlines around the world write in their adverts: "We operate only Li-Ion-free planes", and put streamers on the planes: "Li-Ion free plane"?

What if - lets see...

Of the flying public...
89% of the passengers would say 'Huh? - I don't get it.
10% would say - damn - that means I can't bring my camera/cellphone/computer - better find another airline.
1% would laugh.

Of a.net
27.62597% would laugh at Boeings folly
27.62597% would say AB is either the same or worse.
8.18224% would troll
13.67533% would fall for the troll bait.
12.89% would ask the mods to shut down the thread.
The remaining members would either try to explain the facts or stop reading the thread.

Well - hey- one joke deserves another...

Back to the batteries - It is good to see some progress being made. The current situation is benefiting nobody, nowhere, nohow. Personally - I have high confidence that both the FAA and Boeing want to see the plane in the air, safely, sooner rather than later and there are a lot of very smart, who are not corrupt, not evil and not motivated by greed, working on it.

Topic: RE: FAA Grounds 787, Part 10
Username: BoeingVista
Posted 2013-02-21 01:35:24 and read 14435 times.

Quote:
An Auburn insider said the company ordered 200 such boxes, with the first 100 to be ready by March 18.

Commercial Airplanes CEO Ray Conner will lay out the company’s plan to Federal Aviation Administration officials Friday, but it’s unclear whether regulators will sign on to the fast-paced schedule.

Hold up, Boeing have gone ahead and ordered these new containment boxes before even running the 'fix' past the FAA?

http://seattletimes.com/html/busines...ogy/2020398575_boeingboxesxml.html

Topic: RE: FAA Grounds 787, Part 10
Username: flyglobal
Posted 2013-02-21 03:11:45 and read 14088 times.

Quoting BoeingVista (Reply 124):
Hold up, Boeing have gone ahead and ordered these new containment boxes before even running the 'fix' past the FAA?

http://seattletimes.com/html/busines...ogy/2020398575_boeingboxesxml.html



BV

Sounds plausible as a fix, be it called temporary of final.

So it might prevent a fire in a call to spread around making the problem 1/8th in consequence.
Some doubts, but in general with a fix mature enough it should be possible to get 'more samples' for a rout course identification.

But now given that an incorrect wiring was found, probably with an impact from Battery one to two? THis may turn the story.

Regards

Flyglobal

Topic: RE: FAA Grounds 787, Part 10
Username: XT6Wagon
Posted 2013-02-21 03:17:06 and read 14084 times.

Quoting BoeingVista (Reply 124):
Hold up, Boeing have gone ahead and ordered these new containment boxes before even running the 'fix' past the FAA?

and?

This isn't a grand conspiracy. How do you think they certify parts in the first place? They certainly didn't ask the FAA every time they ordered a new part for the static test frame.

Topic: RE: FAA Grounds 787, Part 10
Username: gemuser
Posted 2013-02-21 04:11:24 and read 14065 times.

Quoting XT6Wagon (Reply 126):
and?

This isn't a grand conspiracy. How do you think they certify parts in the first place? They certainly didn't ask the FAA every time they ordered a new part for the static test frame.

True but to get the AD lifted they need the approval of the Manager Seattle Aircraft Certification Office, I'll bet Boeing engineers are talking to him/her daily, at least.

Gemuser

Topic: RE: FAA Grounds 787, Part 10
Username: bikerthai
Posted 2013-02-21 05:58:13 and read 13691 times.

Quoting BoeingVista (Reply 124):
Hold up, Boeing have gone ahead and ordered these new containment boxes before even running the 'fix' past the FAA?

When you have 50+ planes grounded, you don't do things in series. If you can save a few days lead time by ordering these parts early and get them to the airplanes then it would be well worth it.

If the FAA reject the "containment portion", then the cost of fabricating these 200 box would probably not be more than the cost of compensating for grounding of one aircraft for one day.

Besides if the box is made of titanium, you'd better get in line and order your raw material early.

Finally, if the FAA does reject the fix, they can always put the stop work order before they build too many.


bt

Topic: RE: FAA Grounds 787, Part 10
Username: DTW2HYD
Posted 2013-02-21 06:30:17 and read 13549 times.

Quoting BoeingVista (Reply 124):
Hold up, Boeing have gone ahead and ordered these new containment boxes before even running the 'fix' past the FAA?

No supplier would make one or two boxes as per custom specs. Even if they do it will cost almost same as 100 boxes. So it is easy to place order for large quantity with a firm fence on smaller quantity. I guess to demo it is NTSB,JTSB,FAA and regulators or six countries they definitely need few boxes.

Topic: RE: FAA Grounds 787, Part 10
Username: ServantLeader
Posted 2013-02-21 06:40:07 and read 13485 times.

Quoting DTW2HYD (Reply 129):
No supplier would make one or two boxes as per custom specs. Even if they do it will cost almost same as 100 boxes. So it is easy to place order for large quantity with a firm fence on smaller quantity. I guess to demo it is NTSB,JTSB,FAA and regulators or six countries they definitely need few boxes.

The cost of the containment boxes isn't even a blip on the screen compared to the 787 program cost overruns proper -- no material risk to Boeing to place a production order for the boxes, presumably with a cancellation clause should the FAA reject the fix.

[Edited 2013-02-21 07:00:59]

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-21 07:20:20 and read 13355 times.

Quoting ltbewr (Reply 121):
I am concerned with the FAA in all this. It is a Federal Government agency, mandated to assure aircraft safety but is also subject to politcal pressures...

The FAA did Boeing no favors in grounding the 787, but prematurely lifting said grounding won't do them any favors, either.

Boeing's goal is to get the 787 back into service, but Boeing gains nothing by putting in place an insufficient interim "fix" for the issue to get back into service. Another incident that does not result in injuries will be bad enough - an incident that does lead to injuries or deaths would be truly disastrous.

Even if the FAA would accept the current battery going forward with a better containment system - and indications are the FAA will not - Boeing themselves appear to not accept that and are proactively working on new batteries that would replace the current model in the new containment system.

Topic: RE: FAA Grounds 787, Part 10
Username: par13del
Posted 2013-02-21 07:33:37 and read 13264 times.

Quoting BoeingVista (Reply 124):
Hold up, Boeing have gone ahead and ordered these new containment boxes before even running the 'fix' past the FAA?

I do not see the FAA approving the containment based on computer simulation, nor do I see the FAA getting involved in the design, they are going to mandate the actions / effectiveness of the box.
Boeing and it engineers thus have to design and submit to the FAA for approval.
I see nothing wrong with Boeing submitting its plans to a vendor to have sample built, if the FAA does not approve, Boeing will have to go back to the drawing board all at its own expense, so there is no need to be certain the FAA will approve the design before building samples for testing and certification.

Topic: RE: FAA Grounds 787, Part 10
Username: JHwk
Posted 2013-02-21 08:33:41 and read 12989 times.

Quoting airtechy (Reply 119):
I'm not sure I understand the timing. At the time the batteries caught on "fire", I would think that neither had any current draw. One was in the air and the other parked on the ground....I

From the limited detail in the article, it sounds like the APU could not backfeed the battery, but it could contribute to unintended current draw. This could potentially lead to accelerated aging of the battery.

A more robust containment solves the potential hazard to flight, but you really do need to figure out why the batteries are requiring as many replacements as they have been, which should help explain why the battery reliability is worse than anticipated. This piece of the puzzle may address this second part. (The third part is making sure the battery system is more robust where problems like this cannot lead to accelerated aging.)

Topic: RE: FAA Grounds 787, Part 10
Username: FriendlySkies
Posted 2013-02-21 10:02:27 and read 12725 times.

Quoting JHwk (Reply 133):
A more robust containment solves the potential hazard to flight, but you really do need to figure out why the batteries are requiring as many replacements as they have been

Boeing is certainly aware of that, but is also aware than in a complex system such as this, it may be months or even years before a root cause is nailed down, if one is ever found.

Decreasing the odds of thermal runaway with more separation and better insulation, combined with a robust containment system, is as good a fix as I could think of.

Quoting Stitch (Reply 131):
Even if the FAA would accept the current battery going forward with a better containment system - and indications are the FAA will not

The FAA isn't stupid, and they are also aware that discovery of a root cause could be years away. They will certainly take their time digging into the details on the proposal, but I'm not sure what signs you speak of that would indicate they will deny this fix outright, assuming it is adequately tested and demonstrated to retire the risk.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-21 10:09:29 and read 12727 times.

Quoting FriendlySkies (Reply 134):
They will certainly take their time digging into the details on the proposal, but I'm not sure what signs you speak of that would indicate they will deny this fix outright, assuming it is adequately tested and demonstrated to retire the risk.



I'm one of the people who have been arguing that the FAA would accept a stronger containment system with the existing battery as an interim fix to lift the grounding AD and allow the 787 back into revenue service.

But I do not believe the FAA would consider that the final resolution and that no further action would be required and that Boeing would be allowed to continue to use the current battery for the service life of a 787 airframe.

I believe the FAA will require either a new formulation of Lithium-Ion battery (my guess would be one using lithium iron phosphate cathodes) or moving to a battery using NiCad electrodes as the long-term fix.

[Edited 2013-02-21 10:42:13]

Topic: RE: FAA Grounds 787, Part 10
Username: sweair
Posted 2013-02-21 10:24:27 and read 12660 times.

Is there any news on a cause or is it still a mystery? Never finding the smoking gun would be the worst thing that could happen. I am perplexed that so many flights and test flights were done and no swelling cells have been known before these two incidents happened, what changed since EIS?

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-21 10:49:22 and read 12598 times.

Quoting stasisLAX (Reply 122):
Boeing could have the 787 back into the air within 2 months, according to this New York Times article from today (2/20/13). Special insulation (possibly ceramic) will to used to better contain the batteries according to the article. "Concerned about fires with smaller lithium-ion batteries in cellphones and laptops, the agency (FAA) placed special conditions on Boeing’s use of the batteries that required containment and venting measures that have proved inadequate" to directly quote the article.

This quote sounds rather damning to both the FAA and Boeing.... but let's all hope that there's truly a near-term "fix" coming from Boeing.

Seems that Boeing is going to give it a go to see if a solution with better containment, monitoring, internal stiffness and isolation will pass muster.

I didn't see them mention any change in chemistry, nor any steps to make sure there is/was no contamination during manufacturing.

The article mentions that the FAA will probably require a significant amount of testing, but doesn't mention how they're going to know how much testing is needed given that they failed to detect these issues in the original testing.

Topic: RE: FAA Grounds 787, Part 10
Username: par13del
Posted 2013-02-21 14:24:45 and read 12111 times.

Quoting Revelation (Reply 137):

I didn't see them mention any change in chemistry, nor any steps to make sure there is/was no contamination during manufacturing.

Even is more durable batteries is not a requirement, I'm certain that the other airlines who had not yet had problems with their batteries have noted the high rates of battery changes and will ultimately demand a better product.
Based on the number of items that went off the rails, this may be an item they were going to eventually address, now it is gonna be sooner rather than later, also expect a change in the SOP to ensure that the user pays closer attention to the drain and over use rather than ensuring that ground power is on as soon as possible.

Topic: RE: FAA Grounds 787, Part 10
Username: breiz
Posted 2013-02-21 14:40:42 and read 12064 times.

Quoting prebennorholm (Reply 115):
What if airlines around the world write in their adverts: "We operate only Li-Ion-free planes", and put streamers on the planes: "Li-Ion free plane"?


Will this have any consequence for Lion Air?   

Topic: RE: FAA Grounds 787, Part 10
Username: hamster
Posted 2013-02-21 14:48:19 and read 12075 times.

How did United get permission from FAA to fly 787 from Houston to Seattle during the grounding. Take me through this. Did they need attorneys? How was the FAA approached? how did they respond? What proof do the pilots need to take off? do they need to show documentation?

Topic: RE: FAA Grounds 787, Part 10
Username: FriendlySkies
Posted 2013-02-21 14:50:32 and read 12064 times.

Quoting hamster (Reply 140):

How did United get permission from FAA to fly 787 from Houston to Seattle during the grounding. Take me through this. Did they need attorneys? How was the FAA approached? how did they respond? What proof do the pilots need to take off? do they need to show documentation?

When did that happen? Last I heard UA's 787 fleet was 4x at IAH, 1x at LAX, and 1x at NRT.

Boeing flew an airplane from FTW back to PAE that was stranded to finish delivery preps, and received special FAA permission with a lot of restrictions...no idea on the details though.

Quoting Stitch (Reply 135):
I'm one of the people who have been arguing that the FAA would accept a stronger containment system with the existing battery as an interim fix to lift the grounding AD and allow the 787 back into revenue service.

My mistake, I haven't kept up with this thread. I'm not sure I 100% agree though. Unless and until a root cause is found, short of fully replacing the battery with Ni-Cad, I don't see how the proposed solution is any less safe than a new battery chemistry, so long as the risk can be shown to be adequately controlled.

[Edited 2013-02-21 14:52:22]

Topic: RE: FAA Grounds 787, Part 10
Username: ADent
Posted 2013-02-21 14:54:55 and read 12042 times.

If Boeing is going to stay Li-Ion (any technology, any improvements) they need better containment. Those boxes will be needed (unless they wise up and go NiCd).

I can see any Li-Ion battery being a problem getting approval in certain countries that are not Boeing friendly - say Russia or Europe or China, even in FAA and Japan CAA approve.

Topic: RE: FAA Grounds 787, Part 10
Username: FriendlySkies
Posted 2013-02-21 14:59:41 and read 12043 times.

Quoting ADent (Reply 142):
China, even in FAA and Japan CAA approve.

If the FAA signs off on a fix, China will too (maybe after some grumbling). They can't afford to create poor trade relations with the US.

Topic: RE: FAA Grounds 787, Part 10
Username: gemuser
Posted 2013-02-21 15:07:45 and read 12001 times.

Quoting hamster (Reply 140):
How did United get permission from FAA to fly 787 from Houston to Seattle during the grounding. Take me through this. Did they need attorneys? How was the FAA approached? how did they respond? What proof do the pilots need to take off? do they need to show documentation?

This is a standard procedure. The operator applies for a waiver, giving details of what they want to do, the FAA assesses the application, there maybe some negotiation back & forth over conditions, the FAA reaches a final decision and issues the waiver (if they approve) which specifies the conditions under which the waiver is granted. Totally routine and happens daily, although of course applications involving B787-8 probably get more scrutiny at the moment.

Gemuser

Topic: RE: FAA Grounds 787, Part 10
Username: kanban
Posted 2013-02-21 15:52:03 and read 11900 times.

Quoting Revelation (Reply 137):
I didn't see them mention any change in chemistry, nor any steps to make sure there is/was no contamination during manufacturing.

The absence of mention is most likely because they have not selected the most advantageous chemistry, or the best choice is a lab version with no production capacity or is still in a test mode. This could take some time.

Quoting par13del (Reply 138):
noted the high rates of battery changes

As I recall the bulk of the changes were related to use by ramp crews for interior lighting etc, where they exceeded the allowable time draining the battery to a point where it could not be recharged on the plane. (about 90% of the 100 removals were in this category)

Topic: RE: FAA Grounds 787, Part 10
Username: NAV20
Posted 2013-02-21 17:58:53 and read 11657 times.

Quoting kanban (Reply 145):
As I recall the bulk of the changes were related to use by ramp crews for interior lighting etc, where they exceeded the allowable time draining the battery to a point where it could not be recharged on the plane. (about 90% of the 100 removals were in this category)

Thanks for that, kanban, most illuminating.

It looks as if Boeing are now aiming at a 'complete fix' (that is, including modifications to the batteries to reduce the risk of overheating/short-circuiting), instead of just improving the 'containment.' A bit more detail here:-

http://www.nbcnews.com/business/boei...-battery-fix-source-says-1C8462915

Topic: RE: FAA Grounds 787, Part 10
Username: RickNRoll
Posted 2013-02-21 18:02:37 and read 11636 times.

Quoting kanban (Reply 145):
As I recall the bulk of the changes were related to use by ramp crews for interior lighting etc, where they exceeded the allowable time draining the battery to a point where it could not be recharged on the plane. (about 90% of the 100 removals were in this category)

The regularity of this occurring, along with the current ban on trasporting the conveniently, makes them problematic still. Just saying it's the customers fault isn't going to go down well with the customers.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-21 18:48:36 and read 11520 times.

Quoting RickNRoll (Reply 147):
Just saying it's the customers fault isn't going to go down well with the customers.

It is the customer's responsibility to adhere to the operating instructions for the product. If anything, Boeing's guidelines for battery draw are likely conservative, so that customers are still running them down is a sign to me that said customers need to better brief their staff and contractors (like fuelers, cleaners, etc.).

Topic: RE: FAA Grounds 787, Part 10
Username: francoflier
Posted 2013-02-21 19:00:21 and read 11508 times.

I'm part of those who think the idea of a better containment box is disturbing.

This amounts to pretty much accepting that the batteries will keep catching fire.

And I am skeptical about the thermal insulation between the cells. It will prevent any excess heat from one cell to spread to the next one, but it won't prevent that overheating cell from going berserk. In fact, thermal insulation will prevent proper cooling, won't it?

I'm guessing this would not be made public, but have the actual causes been identified, or are they just best guesses at this stage?

What worries me is that another battery issue, even if properly contained with the new boxes, will create more trouble for Boeing than the benefits of an early return to service...

Topic: RE: FAA Grounds 787, Part 10
Username: JHwk
Posted 2013-02-21 19:08:37 and read 11496 times.

Quoting francoflier (Reply 149):
And I am skeptical about the thermal insulation between the cells. It will prevent any excess heat from one cell to spread to the next one, but it won't prevent that overheating cell from going berserk. In fact, thermal insulation will prevent proper cooling, won't it?

I think that is being described incorrectly. I would have expected just an air gap to prevent conduction, but what is essentially needed is just something to allow a single cell to heat up and "grow", without impacting other cells. The talk of ceramic separators seems completely odd, unless it had some sort of cooling channels going vertically.

The original containment accepted that cells would eventually burn. The idea of strengthened containment is more to accept that when cells eventually burn you want to better control the situation than the original design. It isn't perfect, but that doesn't mean you are accepting a higher battery failure rate-- just that you are trying to protect yourself statistically.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-21 19:22:52 and read 11519 times.

Quoting francoflier (Reply 149):
I'm part of those who think the idea of a better containment box is disturbing.

This amounts to pretty much accepting that the batteries will keep catching fire.

Which is why Boeing and their suppliers are working on a new battery.



Quoting francoflier (Reply 149):
And I am skeptical about the thermal insulation between the cells. It will prevent any excess heat from one cell to spread to the next one, but it won't prevent that overheating cell from going berserk.

But it would prevent the other cells from going thermally berserk. So instead of eight cells entering thermal runway, only one would. Yes, that's not wonderful, but it's better than what happened in JA829J and what looks to appear to have been underway on JA804A.



Quoting francoflier (Reply 149):
I'm guessing this would not be made public, but have the actual causes been identified, or are they just best guesses at this stage?

Investigations are still ongoing and it's all been in the public eye. If they find the cause, it is not going to be a secret.



Quoting francoflier (Reply 149):
What worries me is that another battery issue, even if properly contained with the new boxes, will create more trouble for Boeing than the benefits of an early return to service...

I agree, and evidently so does Boeing, which is why they and their suppliers are working on a new battery.

Topic: RE: FAA Grounds 787, Part 10
Username: NAV20
Posted 2013-02-21 19:40:05 and read 11710 times.

Quoting francoflier (Reply 149):
And I am skeptical about the thermal insulation between the cells.
Quoting JHwk (Reply 150):
I think that is being described incorrectly. I would have expected just an air gap to prevent conduction

Boeing have often said that they're thinking about increased separation. But the mention of plates being inserted between the cells didn't come from them, but from a 'tame professor' contacted by Reuters  :-

"The logical solution for Boeing would be to install ceramic plates between each cell and add a vent to the battery box, Kiyoshi Kanamura, a professor at Tokyo Metropolitan University who has conducted research with several Japanese battery makers, told Reuters on Tuesday."

Topic: RE: FAA Grounds 787, Part 10
Username: fpetrutiu
Posted 2013-02-21 19:52:52 and read 11715 times.

"Boeing Co. is reportedly set to present regulators with a redesigned battery for its 787 Dreamliner that they hope will satisfy safety concerns.

The redesign will include insulation made of heat-resistant glass around each of the lithium-ion battery’s cells and a venting mechanism for fumes as well as a harder case to contain fires. Boeing is said to be developing kits so the new batteries can be easily swapped with the old ones in the same space. " Mike W. Thomas Reporter- San Antonio Business Journal

Article source: http://www.bizjournals.com/sanantoni...id-to-have-redesigned-battery.html

Topic: RE: FAA Grounds 787, Part 10
Username: kanban
Posted 2013-02-21 20:39:49 and read 11561 times.

Quoting RickNRoll (Reply 147):
The regularity of this occurring, along with the current ban on trasporting the conveniently, makes them problematic still. Just saying it's the customers fault isn't going to go down well with the customers.

There are many requirements for the airlines in the area of operation and maintenance.. violating these voids warranties. the battery depletion to the lock out level is a customer problem just like not taxiing with under inflated tires.. Fortunately they can be recharged at a licensed repair station.

Quoting fpetrutiu (Reply 153):
The redesign will include insulation made of heat-resistant glass around each of the lithium-ion battery’s cells and a venting mechanism for fumes as well as a harder case to contain fires. Boeing is said to be developing kits so the new batteries can be easily swapped with the old ones in the same space.

I am suspicious of this statement.. the battery packs are not customer serviceable as far as trading cells.. the new packs will be interchangeable with the existing packs, and maybe Yuasa will sent mod teams to the customers sites to accomplish this mod, however I believe that the moment an airline tampers with or modifies the box contents, the warranty is void.

Now looking at a kit idea, it will probably include new battery packs (in the new containment boxes), ducting and hardware for venting externally, and a requirement to double check all system wiring. Maybe some changes to the controllers, and some monitoring hardware/software.

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-21 21:11:44 and read 11518 times.

Quoting kanban (Reply 154):
I am suspicious of this statement.. the battery packs are not customer serviceable as far as trading cells.. the new packs will be interchangeable with the existing packs, and maybe Yuasa will sent mod teams to the customers sites to accomplish this mod, however I believe that the moment an airline tampers with or modifies the box contents, the warranty is void.

I don't see anything here that says the customers would be doing any battery servicing other than removing one whole battery and replacing it with another--the customer won't be swapping cells. I imagine Boeing will send out trained AOG teams to get this job done correctly--especially for the ducting part.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-21 21:42:37 and read 11494 times.

Quoting fpetrutiu (Reply 153):
Boeing is said to be developing kits so the new batteries can be easily swapped with the old ones in the same space.
Quoting kanban (Reply 154):
I am suspicious of this statement..

This statement could be that Boeing is producing kits so that airlines or MROs can replace the existing containment vessel and battery pack with the new containment vessel, battery pack and venting. This would save them the time of having to fly the planes back to PAE (or another Boeing site) to have the swap drone.

Topic: RE: FAA Grounds 787, Part 10
Username: PHX787
Posted 2013-02-21 23:47:36 and read 11227 times.

I don't know if this was posted yet but UA delayed the launch of the DEN flight until the end of May....

Topic: RE: FAA Grounds 787, Part 10
Username: ADent
Posted 2013-02-21 23:57:19 and read 11264 times.

Quoting FriendlySkies (Reply 143):
If the FAA signs off on a fix, China will too (maybe after some grumbling). They can't afford to create poor trade relations with the US.

Before the grounding there were 787s ready to deliver to China. Looks like 7 787s are about ready to go to China Southern and Hainan, but waiting on Chinese approval.

See http://articles.chicagotribune.com/2...ines-civil-aviation-administration

Quote:
China has been increasingly assertive when it comes to exercising its right to independently certify the airworthiness of western-built aerospace equipment, such as engines, industry sources said.

Topic: RE: FAA Grounds 787, Part 10
Username: rheinwaldner
Posted 2013-02-22 04:00:11 and read 10693 times.

Quoting NAV20 (Reply 146):
It looks as if Boeing are now aiming at a 'complete fix' (that is, including modifications to the batteries to reduce the risk of overheating/short-circuiting), instead of just improving the 'containment.' A bit more detail here:-

So the storyline has changed. No "a better containment is enough to fly"-talk anymore. I still don't get, why some believed the opposite.

Boeing recent communication sounds much more trustworthy than earlier statements.

Also if the root cause could be nailed down to some miswiring, a quick fix would be possible (no redesign, no changed dimensions) and so the end of the grounding would be in sight.

Topic: RE: FAA Grounds 787, Part 10
Username: packsonflight
Posted 2013-02-22 04:25:10 and read 10560 times.

The proposal for redesigning the battery Boeing is submitting to the FAA apparently consists of two major changes:

Improved containment in the case of battery fire, and added insulation between the cells. I fail to see how that is addressing the failure rate of the battery, which is to high. As far as I can see the added insulation is intended to prevent thermal runaway in one cell to spread to the next one or the whole battery, which reduces the risk in case of battery fire.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-22 05:11:06 and read 10378 times.

Quoting packsonflight (Reply 160):
mproved containment in the case of battery fire, and added insulation between the cells. I fail to see how that is addressing the failure rate of the battery, which is to high.

It doesn't. I imagine that is why Yuasa is said to be developing a new battery.

Topic: RE: FAA Grounds 787, Part 10
Username: packsonflight
Posted 2013-02-22 05:30:47 and read 10272 times.

Quoting Stitch (Reply 161):
It doesn't. I imagine that is why Yuasa is said to be developing a new battery.

But still Boeing is advocating this as a permanent battery fix


http://seattletimes.com/html/busines...ogy/2020398769_boeingboxesxml.html

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-22 05:49:50 and read 10205 times.

Quoting packsonflight (Reply 160):
The proposal for redesigning the battery Boeing is submitting to the FAA apparently consists of two major changes:

Improved containment in the case of battery fire, and added insulation between the cells. I fail to see how that is addressing the failure rate of the battery, which is to high. As far as I can see the added insulation is intended to prevent thermal runaway in one cell to spread to the next one or the whole battery, which reduces the risk in case of battery fire.

Yes, I too find it interesting that there's no mention of anything being done to improve the individual cells, rather it's all focused on the packaging of the cells within the battery along with improved monitoring, containment, venting, etc.

The improved insulation would provide less heat transfer between the cells which presumably is an attempt to prevent a single cell from entering thermal runaway due to aggregate heat buildup. The NYT article also mentions the entire device would be more rigid so perhaps vibration issues would be mitigated. It also mentions attempts to control humidity.

An earlier ST article said:

Quote:

Battery experts caution that while the most likely culprit is a tiny metal shard contaminating the cell during the manufacturing process, the root cause may never be definitively proved because of destruction from the thermal runaway.

Which is why I keep finding it interesting that nothing is being said about addressing the individual cells and/or their manufacturing process.

We also have the NTSB's stated concern that the failure rate is higher than predicted.

It will be interesting to see how this plays out. We could find that increased rigidity and thermal isolation causes a reduction in both single cell and multi-cell failures. However, if the end result is a noticeable rate of single cell failures resulting in diversions I doubt the end result will be satisfactory.

I also wonder if the improved containment and venting will prevent the foul odor that a single cell burning will still produce from being noticed in the cabin. I'm asking because that might cause concern or even panic amongst the passengers.

Topic: RE: FAA Grounds 787, Part 10
Username: bikerthai
Posted 2013-02-22 06:13:26 and read 10116 times.

I wish Tom was here to explain everything. But I venture to guess he may have been told to keep quiet until the full details are presented to FAA and everything is approved.

Here's my best shot at interpreting all the stuff I read from the press:

1) The containment box is only a temporary fix.
2) The containment box is by itself is not the only thing being done as a temporary fix.
3) The flight crew will be monitoring these battery during the flight to catch any anomaly and shut that system down before the cell go catastrophic. IMO this may be the primary OP to keep the 787 flying until the permanent fix is available.

As we in A-net have been told again and again that each airplane has multiple protection scheme for every system. So don't fall into the trap that the containment box itself is the only "fix" Boeing will use to get the planes flying again. The box is only the last resort in case the battery catch fire.

4) The permanent fix will be a battery re-design which may or may not include the "cell" separator, built in fire-proof containment box and battery/cell venting.
5) My guess would also be that a more robust battery monitoring procedure would be included in the software to make it more automatic and alleviate the flight crew from having to do it.
6) There may be other layers of changes that have not yet been discussed - perhaps a different cell charging profile.

Asside: Why is NI-Cd an alternate to Li-Ion? Wouldn't Ni-MH be a better fix?

bt

Topic: RE: FAA Grounds 787, Part 10
Username: ContnlEliteCMH
Posted 2013-02-22 07:01:52 and read 9920 times.

Quoting kanban (Reply 154):
battery depletion to the lock out level is a customer problem just like not taxiing with under inflated tires.

Customer misuse is *a* reason why the batteries can be depleted to or beyond a level at which the onboard system cannot recharge them, but it's not the only reason. It's possible that so many batteries have had to be replaced simply because the airlines are misusing them, but it's also possible that there is some other problem that is causing depletion.

These could include...

... unintended load on the battery even when there is not supposed to be any load.
... undercharging: failure to achieve full charge even though the monitoring unit says it is fully charged.
... damage caused by overcharging.

I spent a couple days this week reading about lithium-based (and other types of) batteries. Very interesting stuff. BatteryUniversity.com (a lot of their material comes from Cadex) provides some well-structured information on batteries of various types, and they describe the charging cycles for several types of battery. One lesson is that a load on a battery when it is being charge may alter the accuracy of the monitoring unit. A second is that some batteries have a wider tolerance at peak charge and some don't. Lithium-based batteries tend to be less tolerant.

I'm not exonerating the airlines of blame and I'm not saying that undercharging/overcharging is a problem. I'm pointing out that a little knowledge makes it easy to imagine possibilities that undermine the hard-and-fast opinion offered above. The truth is that nobody here knows the details of the investigation beyond what they read in the press and that's not very detailed, so a little "opinion couching" is probably warranted.

Topic: RE: FAA Grounds 787, Part 10
Username: gulfstream650
Posted 2013-02-22 07:11:11 and read 9872 times.

Quoting francoflier (Reply 149):

I'm part of those who think the idea of a better containment box is disturbing.

This amounts to pretty much accepting that the batteries will keep catching fire.

Agreed. My perspective is that the plane should stay grounded until the new fix is installed and approved by the FAA.

No bush mechanics; it has to be done properly and done right.

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-22 07:16:18 and read 9888 times.

Quoting bikerthai (Reply 164):
1) The containment box is only a temporary fix.

IMHO the NYT article at http://www.nytimes.com/2013/02/21/bu...-propose-battery-fixes-to-faa.html indicates that Boeing is trying to get a non-temporary fix approved. It seems likely that there is a longer term plan for a re-designed battery, but it seems Boeing wants that to be independent of the containment plan. Maybe we are saying the same thing, but to me a temporary fix plan would need to state that it's temporary, and I haven't seen that in any of the reports.

Quote:

Boeing officials said they had also hoped to make all the fixes at once rather than dividing them into temporary and longer-term changes. By delaying some changes, Boeing could have been exposed to more problems.

As a result, one big change under Boeing's plan would be to redesign the batteries to place insulation inside and around each of the eight cells to minimize the risk that a short circuit or fire in one of the cells could spread to the others, as investigators have said occurred on the battery that caught fire in Boston on Jan. 7. Boeing might also adjust how tightly the batteries are packed.

Boeing would make other changes within the batteries to reduce the chance that vibrations, swelling or moisture could cause problems, industry officials said. Boeing has already been testing some of the changes. The plane maker believes it could rebuild the batteries by next month on the 50 jets that have been delivered to airlines. But federal officials are likely to move more slowly and demand more tests and assurances, and the final decision could rest with Mr. Huerta's supervisors at the Transportation Department.

Besides taking more steps to prevent short circuits from occurring, Boeing's plan would enclose the battery within a sturdier metal container and create tubes to vent any hazardous materials outside the plane. It would add systems to monitor the activity inside each cell instead of just the battery as a whole.

Seems Mr. Connor and Mr. Huerta will be meeting today to discuss this plan.

Hope it goes well!

Seems to me to be worth noting that while this is a very senior meeting between the head of the FAA and the head of BCA, that if either party views the outcome unfavorably there is an escalation path to the head of the DOT and the CEO of Boeing.

Topic: RE: FAA Grounds 787, Part 10
Username: rcair1
Posted 2013-02-22 08:41:22 and read 9506 times.

Quoting fpetrutiu (Reply 153):
Boeing is said to be developing kits so the new batteries can be easily swapped with the old ones in the same space. " Mike W. Thomas Reporter- San Antonio Business Journal
Quoting kanban (Reply 154):
I am suspicious of this statement..

I believe this is using the term "battery" to include the entire assembly - not the "cells" in a battery.

If you ignore all the conspiracy theories and accusations of massive incompetence - it is pretty clear what Boeing is doing.

Step 1)
They are proposing a fix to the containment structure which will increase the safety if a cell goes into runaway. They doing this by:
a) preventing heat from 1 runaway cell spreading to another (insulation between cells).
b) reducing the fuel load in a fire - (same as a).
c) Improving the containment system to be more robust.
d) Likely improving monitoring and vibration resistance.

This approach assumes that they cannot guarantee a battery will not go into thermal runaway - which, BTW, was always true and is no different today.
- No matter what battery they put in - they will have some type of containment.

This is not being presented as a 'Temporary Fix" for obvious reasons.
1) They do not want a time limit associated with a redesign. I believe they will design away from Li-Ion or change chemistry - however, they want to do this on their schedule, not a FAA schedule.

Step 2) (parallel not serial).
At the same time they are investigating a re-design that will either replace the battery with a non Li-Ion one, or improve the Li-Ion technology to address reliability and safety issues.
Again - they want to do this on their schedule. I would to the same.

I fully believe that if they cannot get the FAA and other authorities (not NTSB) to buy off on a "non-temporary" (not saying permanent) fix - they will move to a "temporary" fix plan.
The only change this will cause is that the re-design will be on an FAA schedule, not a Boeing schedule.

This is not rocket science..

Quoting bikerthai (Reply 164):
Asside: Why is NI-Cd an alternate to Li-Ion? Wouldn't Ni-MH be a better fix?

NiMH has 2 problems compared to either Li-Ion and NiCad (ignoring capacity.)
NiMH has a much higher self discharge rate.
- A NiMH will loose 20% capacity at 70F in 30 days (240 hr). It will loose 40% at 100F
- A NiCad will loose 20% at 70F in 10 weeks (560H) and will loose 70% in 20 weeks (1020 hr)

Self discharge is not a large factor for a/c operations though.

More important is the temperature characteristics.
At -20C
NiMH will retain only 20% of it's capacity.
NiCad is at 60% capacity.

Of course, NiCad has issues too - the most problematic for a/c is memory effect.

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-22 08:59:13 and read 9419 times.

Quoting rcair1 (Reply 168):
If you ignore all the conspiracy theories and accusations of massive incompetence - it is pretty clear what Boeing is doing.

Step 1)
They are proposing a fix to the containment structure which will increase the safety if a cell goes into runaway.

Indeed, but it's not clear to me that this is sufficient. I think it's safe to presume most commercial 787 pilots will divert if only one cell goes into runaway and if this happens anywhere near the two events in ten days frequency it won't pass muster. I suppose time will tell, but I have to wonder what the impact of one more incident of pax evacuating down the chutes would have on the 787 program.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-22 09:16:28 and read 9344 times.

Quoting Revelation (Reply 169):
Indeed, but it's not clear to me that this is sufficient. I think it's safe to presume most commercial 787 pilots will divert if only one cell goes into runaway and if this happens anywhere near the two events in ten days frequency it won't pass muster.

I would like to believe the end-goal of these redesigns is to not just prevent a thermal runaway in a single cell from propagating to other cells, but to prevent a thermal runaway in a cell, period as that's part of the FAA's Special Conditions.

Topic: RE: FAA Grounds 787, Part 10
Username: blrsea
Posted 2013-02-22 09:25:49 and read 9281 times.

Quoting NYT article (Reply 167):
As a result, one big change under Boeing's plan would be to redesign the batteries to place insulation inside and around each of the eight cells to minimize the risk that a short circuit or fire in one of the cells could spread to the others, as investigators have said occurred on the battery that caught fire in Boston on Jan. 7. Boeing might also adjust how tightly the batteries are packed.

Would these have any effect on the battery efficiency itself? If not, why wasn't this thought of earlier itself as effects of thermal runaway were well known for Li-Ion batteries?

Topic: RE: FAA Grounds 787, Part 10
Username: ikramerica
Posted 2013-02-22 09:37:39 and read 9249 times.

What's truly silly about this whole thing is that the two failures were not in the same system, not the same kind of failure, and yet were "linked" because they were both batteries. This led to conflation by the media and public, and many on anet, that there were two battery "fires".

If every type was grounded because of one off wiring mistakes and one off component failures, there would be no aircraft flying today.

It is my firm belief that the 787 is grounded due to a cascade of CYA actions that begins with the utter failure of the Japanese nuclear regulatory agency to properly monitor their power plants and their safety agencies to properly monitor safety certification of cars, aircraft seats, etc. In other words, if it wasn't JL and NH with these issues, the 787 would be in revenue service while the investigation continued.

Is it a bad thing that it is grounded without a single fatality, hull loss, etc? It's unprecedented, that's for sure. And no more people have died since the grounding. That proves it is warranted.

If only the cruise ship, bus, train, ferry, name your transport here, amusement park, etc. industries were held to such a high standard.

Topic: RE: FAA Grounds 787, Part 10
Username: sankaps
Posted 2013-02-22 10:13:47 and read 9165 times.

Today's Wall Street Journal has some interesting tidbits relating to Boeing CEO McNerney's reactions to, and handling of, the crisis.

Two things especially caught my attention. First, upon hearing of the ANA incident, McNerney called Boeing Commercial Chief Connor and said "The battery problem isn't a one-off anymore".

Second, upon being told by his Chief Technology Officer the next day that "nothing that happened posed a risk to the plane of the passengers", McNerney banged his hands on the desk and said "Do you understand the meaning of what we're dealing with here?" [The issue is not just] "electrochemistry in a battery... its about the safety and confidence in our planes and our brand. And it can't happen again."

In other words, he was not in denial, excuses, and arcane technical explanations mode, he saw the bigger picture immediately.

And for that he certainly earns my respect.

Topic: RE: FAA Grounds 787, Part 10
Username: kanban
Posted 2013-02-22 10:14:57 and read 9116 times.

Quoting rcair1 (Reply 168):
If you ignore all the conspiracy theories and accusations of massive incompetence - it is pretty clear what Boeing is doing.

Glad to see you're hanging in there while we wait for clear answers..

My comment was mainly relative to the journalism which to me alluded to airlines doing more than they would normally be allowed to do on vendor proprietary LRUs.

the kit approach with new batteries in a new containment box and parts kits/instructions better fit airline capabilities

Topic: RE: FAA Grounds 787, Part 10
Username: lightsaber
Posted 2013-02-22 10:26:20 and read 9130 times.

I was razed on a.net for predicting the 787 grounding would last a few months. I'm sad the grounding looks like it will go 50%+ longer than I estimated. But that is what it takes to solve aviation problems. There are shortcuts, but only so many...

Quoting Stitch (Reply 170):
I would like to believe the end-goal of these redesigns is to not just prevent a thermal runaway in a single cell from propagating to other cells,

I do not think it is possible. This at least keeps it contained. But I know *nothing* about batteries (other than understanding the chemistry to a certain, but not expert degree).

Quoting ikramerica (Reply 172):
If every type was grounded because of one off wiring mistakes and one off component failures, there would be no aircraft flying today.

   But they are grounded and thus must go through steps to be airborne again.

Quoting ikramerica (Reply 172):
If only the cruise ship, bus, train, ferry, name your transport here, amusement park, etc. industries were held to such a high standard.

Or medicine... If medicine adopted Aerospace proceedure techniques, lives would be saved. But your point is valid, the 787 has been held to an unusually high standard. Cest la vie. I didn't agree with the grounding, but once it happened, it takes on a life of its own.  

Boeing had TWO QA issues with the 787: The fuel valve coating *and* the wiring to the battery/lights. I hope Boeing QA 'wakes up.'

Lightsaber

Topic: RE: FAA Grounds 787, Part 10
Username: ServantLeader
Posted 2013-02-22 10:52:03 and read 8978 times.

Quoting sankaps (Reply 173):
In other words, he was not in denial, excuses, and arcane technical explanations mode, he saw the bigger picture immediately.

And for that he certainly earns my respect.

The 787 program has been plagued with problems since 2008 when delivery dates first started to slip -- that's a 5 year run of being behind the curve and screams of a denial modus operendi -- McNerney should have been fired circa 2011 for this pitiful performance, but since he is both CEO and COB, he is in the enviable position of being able to throw others under the bus.

Topic: RE: FAA Grounds 787, Part 10
Username: sweair
Posted 2013-02-22 11:31:04 and read 8973 times.

Please keep the thread on topic, all the interesting information gets lost in all crap posted that has nothing to do with the topic!

What is the latest news?

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-22 12:31:47 and read 8761 times.

Quoting ikramerica (Reply 172):
If every type was grounded because of one off wiring mistakes

Not sure what you are referring to.

Quote:

JTSB chairman Norihiro Goto told reporters that the incorrect wiring did not likely cause the overheating of the ANA 787’s main battery, but added that the wiring issue concerned him and warranted further investigation, according to multiple reports from Tokyo.

Ref: http://atwonline.com/aircraft-engine...ncorrect-wiring-found-ana-787-0221

Quoting lightsaber (Reply 175):
Boeing had TWO QA issues with the 787: The fuel valve coating *and* the wiring to the battery/lights. I hope Boeing QA 'wakes up.'

There definitely are some loose ends out there:

Quote:

An oil leak was caused by an improper paint job that led to a switch not working properly, while inadequate taping led to cracks in cockpit glass, and a faulty part led to braking problems, according to the Transport Ministry's investigation released Friday into problems that occurred with the 787 Dreamliner in January.

Ref: http://www.huffingtonpost.com/huff-w...ing-787/?utm_hp_ref=green&ir=green

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-22 13:04:07 and read 8585 times.

Quoting Revelation (Reply 178):
Quote:
An oil leak was caused by an improper paint job that led to a switch not working properly, while inadequate taping led to cracks in cockpit glass, and a faulty part led to braking problems, according to the Transport Ministry's investigation released Friday into problems that occurred with the 787 Dreamliner in January.

All of which on any other airplane (except the A380 or the 787 five years from now) wouldn't have sen the light of day.

Topic: RE: FAA Grounds 787, Part 10
Username: KarelXWB
Posted 2013-02-22 13:11:24 and read 8593 times.

Quoting sweair (Reply 177):
What is the latest news?

Now updated by Reuters:

- Boeing will not propose abandoning the lithium-ion batteries
- The proposal includes insulation between the cells of the battery and a stronger, stainless steel box with a venting tube to contain a fire and expel fumes outside the aircraft should a battery catch fire again
- Boeing's proposal to the FAA is not a temporary "band-aid"
- Boeing is not working on a backup or longer-term fix for the problem, no one is on the Plan-B team

Full article http://www.reuters.com/article/2013/...eing-787-faa-idUSBRE91L11U20130222

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-22 14:29:38 and read 8272 times.

Quoting KarelXWB (Reply 180):
Boeing is not working on a backup or longer-term fix for the problem, no one is on the Plan-B team

Call me skeptical, but I don't buy that. I've been around corporate life too long to think no one is working on plan B, and this statement from an unnamed source really reeks of corporate spin.

Also http://www.reuters.com/article/2013/...7-faa-review-idUSBRE91L16W20130222 says:

Quote:

Deputy Transportation Secretary John Porcari, FAA Administrator Michael Huerta and other FAA officials met with senior Boeing executives earlier Friday to discuss the status of ongoing work to address 787 battery issues, said FAA spokeswoman Laura Brown.

"The FAA is reviewing a Boeing proposal and will analyze it closely," Brown said. "The safety of the flying public is our top priority and we won't allow the 787 to return to commercial service until we're confident that any proposed solution has addressed the battery failure risks."

Note that they said "battery failure RISKS" not just "battery failures", which seems to be saying in a subtle way that the FAA is going to support the containment solution.

Topic: RE: FAA Grounds 787, Part 10
Username: tugger
Posted 2013-02-22 14:38:23 and read 8216 times.

Quoting Revelation (Reply 181):
Call me skeptical, but I don't buy that. I've been around corporate life too long to think no one is working on plan B, and this statement from an unnamed source really reeks of corporate spin.

I dunno, once I realized that any "Plan B" full scale change out of what is used would require a recert and that time that required, I think the company is pretty much "all in" with proving that with these additional safeguards the current system is safe and acceptable .

They may have a "B Team" but that is a massive money losing proposition. Best to go with proving the certified stuff safe.

Tugg

Topic: RE: FAA Grounds 787, Part 10
Username: JHwk
Posted 2013-02-22 14:55:13 and read 8145 times.

Quoting tugger (Reply 182):

Agree. They are admitting that this is the extent of what they could do in a palatable time frame. It doesn't preclude more improvements moving forward, but it limits constraints placed on what they are doing.

It also seems to suggest that they are doing all of the component issues they could to provide a safe environment.

Topic: RE: FAA Grounds 787, Part 10
Username: KarelXWB
Posted 2013-02-22 15:12:26 and read 8088 times.

I'm wondering if Boeing really needs a "plan B" (unless the FAA wants it). It's very common to replace aircraft parts often and there is no problem if the battery fails as long as the containment system can guarantee a 100% safety.

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-22 15:33:18 and read 8010 times.

Quoting KarelXWB (Reply 184):
I'm wondering if Boeing really needs a "plan B" (unless the FAA wants it). It's very common to replace aircraft parts often and there is no problem if the battery fails as long as the containment system can guarantee a 100% safety.

Assuming the two failures were not a statistical fluke, I would have to believe that the airlines would want batteries with a longer MTBF - and here "F" means both "failure" and "fire".

Hence my belief that Boeing will, by choice or by force, move to a more stable cathode chemistry. It's been suggested that lithium iron phosphate would need a ninth cell to provide the same power, but based on the Sandia National Labs testing, it looks to be orders of magnitude more stable than the current lithium cobalt oxide. And when it does enter thermal runaway, the temperature is significantly lower and the rate of temperature rise is also significantly lower.

[Edited 2013-02-22 16:07:32]

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-22 15:37:22 and read 8021 times.

Quoting tugger (Reply 182):
They may have a "B Team" but that is a massive money losing proposition.
Quoting JHwk (Reply 183):
They are admitting that this is the extent of what they could do in a palatable time frame.

IMHO an interesting contrast to what the FAA is saying:

Quoting Revelation (Reply 181):
The safety of the flying public is our top priority

Topic: RE: FAA Grounds 787, Part 10
Username: tugger
Posted 2013-02-22 15:42:56 and read 7957 times.

Quoting Revelation (Reply 186):

IMHO an interesting contrast to what the FAA is saying:

Quoting Revelation (Reply 181):
The safety of the flying public is our top priority

I don't see why both can't be applied and be OK. There is no way to overlook cost, even when the "safety of the flying public" is involved. That is what risk is all about, cost versus benefit. Boeing wants no less a safe aircraft than the FAA.

Right now the apparent risk is too high and Boeing's job is to show that it is, or can be brought to be, within accepted risk tolerance limits.

Tugg

Topic: RE: FAA Grounds 787, Part 10
Username: CALTECH
Posted 2013-02-22 15:58:37 and read 7931 times.

Boeing has a plan for the fix.

AP sources: Boeing proposes battery fix for 787s

http://news.yahoo.com/ap-sources-boe...es-battery-fix-787s-205323948.html

Topic: RE: FAA Grounds 787, Part 10
Username: PanAmPaul
Posted 2013-02-22 16:29:26 and read 7798 times.

The FAA issued a statement today after the Boeing meeting, as did Boeing. At least the two sides are talking.

FAA Says Boeing Needs to Address Battery Risks Before Dreamliners Will Fly Again

"Federal Aviation Administration officials announced they are reviewing a proposal from Boeing to allow the Dreamliner to fly again, following a meeting on Friday between FAA Administrator Michael Huerta, Deputy Transportation Secretary John Porcari, and senior Boeing executives including including Ray Conner, head of the aircraft maker’s commercial airplanes unit...."

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-22 17:11:02 and read 7617 times.

Quoting tugger (Reply 187):
I don't see why both can't be applied and be OK.

I agree, but I'm concerned that it seems the root cause and the probability of failure of the individual cells is not well understood, while we see the rush towards the financially prudent course of action. Boeing could easily find that the root cause rears its ugly head again shortly after implementing the proposed changes and find themselves wishing that they paid more attention to Plan B, but hey, big money's on the line so it seems we're going to go down the expedient path first...

Topic: RE: FAA Grounds 787, Part 10
Username: BoeingVista
Posted 2013-02-22 17:23:05 and read 7589 times.

Quoting KarelXWB (Reply 184):

I'm wondering if Boeing really needs a "plan B" (unless the FAA wants it). It's very common to replace aircraft parts often and there is no problem if the battery fails as long as the containment system can guarantee a 100% safety.

The battery supports emergency functions in case of other failures so you cannot say that battery failures are of no concern as long as they are physically contained.

Topic: RE: FAA Grounds 787, Part 10
Username: blrsea
Posted 2013-02-22 17:26:29 and read 7580 times.

Quoting BoeingVista (Reply 191):
The battery supports emergency functions in case of other failures so you cannot say that battery failures are of no concern as long as they are physically contained.

I think the MEL checklist already contains checking the battery. The fact that ANA has replaced more than 10 batteries on its 787s so far indicate that they do check the batteries regularly. And I guess the cockpit displays indicate that too.

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-22 17:41:04 and read 7550 times.

Quoting blrsea (Reply 192):
I think the MEL checklist already contains checking the battery. The fact that ANA has replaced more than 10 batteries on its 787s so far indicate that they do check the batteries regularly. And I guess the cockpit displays indicate that too.

The MEL probably states you can fly without the APU battery subject to restrictions but probably nothing about the main battery because you can't leave home without it. Checking both batteries for a minimum level is probably a maintenance requirement every morning prior to operations.

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-22 18:15:41 and read 7417 times.

Quoting BoeingVista (Reply 191):
The battery supports emergency functions in case of other failures so you cannot say that battery failures are of no concern as long as they are physically contained.

True, battery failures are of concern, however if you're down to the Main battery in an emergency it's not your day. The only thing that the battery would support for more than a few seconds is the brakes which means you may not stop at the end of the runway.

Topic: RE: FAA Grounds 787, Part 10
Username: mke717spotter
Posted 2013-02-22 18:45:52 and read 7354 times.

So with this new proposed fix, will all the delivered 787s need to fly back to PAE to get their batteries modified, or will it be done on-site?

Topic: RE: FAA Grounds 787, Part 10
Username: Stitch
Posted 2013-02-22 18:55:02 and read 7339 times.

Quoting mke717spotter (Reply 195):
So with this new proposed fix, will all the delivered 787s need to fly back to PAE to get their batteries modified, or will it be done on-site?

It sounds like Boeing might be developing a field-replaceable kit.

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-22 19:00:43 and read 7331 times.

Quoting mke717spotter (Reply 195):
So with this new proposed fix, will all the delivered 787s need to fly back to PAE to get their batteries modified, or will it be done on-site?

Boeing will put together service bulletin "kits" and ship then to the airlines. They may send out AOG personnel to support the customers installation depending on how difficult the installation is. Also included will be any operational changes for either or both of the ground and flight crews. Flying back to PAE for modification doesn't really make sense in this case.

Topic: RE: FAA Grounds 787, Part 10
Username: NAV20
Posted 2013-02-22 19:14:23 and read 7274 times.

Quoting 7BOEING7 (Reply 197):
Flying back to PAE for modification doesn't really make sense in this case.

Especially since they'd be flying with the (suspect) unfixed batteries?  

One thing that puzzles me is that there've been no reports of any further test flights by Boeing yet? Surely the altered battery setup will have to be very thoroughly tested before the FAA will even think of lifting the grounding?

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-22 19:32:12 and read 7239 times.

Quoting NAV20 (Reply 198):
One thing that puzzles me is that there've been no reports of any further test flights by Boeing yet? Surely the altered battery setup will have to be very thoroughly tested before the FAA will even think of lifting the grounding?

The two recent flights of ZA005 were for checking out battery instrumentation prior to installing the fix according to the local (KING TV) news earlier tonight. Any test flights for the new setup won't happen until after the FAA determines that it's a valid way to go and agrees to the required test conditions. There may be a lot of ground tests before it ever makes it into the airplane but the whole process will probably move forward much quicker than it normally does.

Topic: RE: FAA Grounds 787, Part 10
Username: PW100
Posted 2013-02-22 19:34:58 and read 7255 times.

Quoting Stitch (Reply 170):
I would like to believe the end-goal of these redesigns is to not just prevent a thermal runaway in a single cell from propagating to other cells, but to prevent a thermal runaway in a cell, period as that's part of the FAA's Special Conditions

But the current proposed solution . . .

Quoting rcair1 (Reply 168):
a) preventing heat from 1 runaway cell spreading to another (insulation between cells).

. . . may perhaps have an opposite effect. By applying any form of insulation, you do reduce/prevent the cascade type failure; however you may INCREASE the single cell failure (if for all else equal), as the single cell can now no longer off load a portion of it's thermal energy to other cells. This may increase the single cell failure rate.

Quoting ikramerica (Reply 172):
It is my firm belief that the 787 is grounded due to a cascade of CYA actions that begins with the utter failure of the Japanese nuclear regulatory agency to properly monitor their power plants and their safety agencies to properly monitor safety certification of cars, aircraft seats, etc. In other words, if it wasn't JL and NH with these issues, the 787 would be in revenue service while the investigation continued.

I have a hard time accepting that CYA actions by Japanese nuclear regulatory agency would in any way effect FAA decision making process.

I think you are missing the big picture here, seeing a lot of trees, but missing the bush.

The Nr.1 reason FAA issued the AD (which in effect grounded the 787 fleet) was the fact that Boeing had earlier claimed/demonstrated to a satisfactory level in the design certification, that such an event (battery thermal runaway) would happen less than once in a million hours. Once such an event happened twice in 50,000 hours, or less than two weeks apart, the whole certification basis of the 787 Type Certificate fell away, and the FAA had no other option.

Basically, the AD says Boeing has to redo this part of the design certification, and demonstrate how they will meet their earlier claims, and more importantly, how they can prove their assumptions. And you can count on it that this time there will be a lot more scrutiny than the first time around, when Boeing had a significant level of “delegated authority” to sort of self-demonstrate that the design met certification standards.



Rgds,
PW100

Topic: RE: FAA Grounds 787, Part 10
Username: cornutt
Posted 2013-02-22 21:07:47 and read 6979 times.

Quoting 7BOEING7 (Reply 194):
True, battery failures are of concern, however if you're down to the Main battery in an emergency it's not your day.

This. If you're down to needing the battery for power in flight, you've had at least four failures: both engines, the APU (or its generator), and the RAT have all failed. I don't know that that's ever happened all in one flight. The one concern is that the engines and APU are subject to a common-cause failure: fuel exhaustion. I could see a MEL provision that you could fly without the main battery provided that extra fuel is carried.

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-22 21:57:42 and read 7089 times.

Quoting cornutt (Reply 201):
I could see a MEL provision that you could fly without the main battery provided that extra fuel is carried.

The MEL as well as Emergency Checklists are not predicated on multiple failures. The MAIN battery is there (should all 4 engine generators fail) to power the Captain's instruments momentarily until the RAT deploys ( a failure mode designed to)--if your fuel is exhausted, after the RAT deploys you no longer need the MAIN battery unless you're in gliding distance of an airport because its only use then is to power the brakes--no runway, no need. If the RAT does not deploy and the APU not start (a failure mode not designed to) you'll have the Captain's instruments until the battery runs out which I'm guessing will be less than 30 minutes (on average) if not a lot less. Have a nice day.

Topic: RE: FAA Grounds 787, Part 10
Username: Unflug
Posted 2013-02-22 22:09:15 and read 7087 times.

Quoting sankaps (Reply 173):
In other words, he was not in denial, excuses, and arcane technical explanations mode, he saw the bigger picture immediately.

And for that he certainly earns my respect.

That's correct. Imagine the guy in his position would have this attitude:

Quoting ikramerica (Reply 172):
What's truly silly about this whole thing is that the two failures were not in the same system, not the same kind of failure, and yet were "linked" because they were both batteries. This led to conflation by the media and public, and many on anet, that there were two battery "fires".
Quoting 7BOEING7 (Reply 202):
Have a nice day.

These threads are certainly not funny. But you made my day today  

Topic: RE: FAA Grounds 787, Part 10
Username: sweair
Posted 2013-02-22 23:29:06 and read 6915 times.

I still think they aim to change the battery chemistry, but that will be a longer term fix, it will need to be re certified and will take more than a year at least.

When that new battery is ready and certified it will be retrofitted to all 787s flying. Until B comes out publicly saying a modified box is the ONLY fix, I will believe it, everything else is just guessing and rumours.

Topic: RE: FAA Grounds 787, Part 10
Username: scbriml
Posted 2013-02-22 23:55:10 and read 6869 times.

Quoting ikramerica (Reply 172):
If every type was grounded because of one off wiring mistakes and one off component failures, there would be no aircraft flying today.

Until every 787 has been inspected, we won't know if these really are "one off" issues.

The Japanese investigators' findings are somewhat worrying - suggesting a failure of Q&A at Boeing in the rush to get 787s to the customers after all the delays.
http://www.foxnews.com/world/2013/02...-problems-but-still-investigating/

Quote:
Japanese investigators have identified the causes of fuel leaks and other problems with Boeing's 787 but are still investigating the more serious battery problem that forced an emergency landing in January and the worldwide grounding of the jets.
...
An oil leak was caused by an improper paint job that led to a switch not working properly
...
while inadequate taping led to cracks in cockpit glass
...
and a faulty part led to braking problems
...
the Japanese ministry said this week it had found the ANA jet's auxiliary power unit had been erroneously wired to the main battery that overheated

Topic: RE: FAA Grounds 787, Part 10
Username: Braybuddy
Posted 2013-02-23 00:14:49 and read 6788 times.

Quoting ikramerica (Reply 172):
It is my firm belief that the 787 is grounded due to a cascade of CYA actions that begins with the utter failure of the Japanese nuclear regulatory agency to properly monitor their power plants and their safety agencies to properly monitor safety certification of cars, aircraft seats, etc. In other words, if it wasn't JL and NH with these issues, the 787 would be in revenue service while the investigation continued.

I'd say it's more to to with the fact we are living in a time when higher and higher saftey standards are not only expected, they are the rule, which may be tough for the manufacturers, but can only be good for passengers. If you were selecting your seat twenty years ago the first question you were asked was "Smoking or non-smoking", which seems absolutely ridiculous now. And I remember in the mid-'80s aviation insurers were expecting to live with one major hull-loss every month, which seems extrarodinary now.

Topic: RE: FAA Grounds 787, Part 10
Username: rwessel
Posted 2013-02-23 03:51:12 and read 6291 times.

Quoting rcair1 (Reply 168):
I believe this is using the term "battery" to include the entire assembly - not the "cells" in a battery.

Technically, a battery is always an assembly of cells, and a single cell device, for example a AA "battery", shouldn't be called a battery at all. Common usage is rather more flexible, though.

Topic: RE: FAA Grounds 787, Part 10
Username: Kaiarahi
Posted 2013-02-23 04:37:07 and read 6192 times.

Quoting ikramerica (Reply 172):
What's truly silly about this whole thing is that the two failures were not in the same system, not the same kind of failure, and yet were "linked" because they were both batteries.

Wrong. 1) The APU and main batteries are identical - they're designed to be interchangeable. 2) They're interconnected - the APU battery also draws on the main for APU starts.

Quoting ikramerica (Reply 172):
This led to conflation by the media and public, and many on anet, that there were two battery "fires".

There were.

Quoting ikramerica (Reply 172):
It is my firm belief that the 787 is grounded due to a cascade of CYA actions that begins with the utter failure of the Japanese nuclear regulatory agency to properly monitor their power plants and their safety agencies to properly monitor safety certification of cars, aircraft seats, etc.

You seem to have a problem understanding the sequence of events, even though it's been explained here multiple times. NH and JL voluntarily grounded their 787 fleets following the second incident. Then the FAA issued the grounding directive. Then the JAA (and other country's authorities) issued a grounding directive.

Topic: RE: FAA Grounds 787, Part 10
Username: sweair
Posted 2013-02-23 04:43:14 and read 6201 times.

I would fly on the not fixed 787 tomorrow if possible, I don't think it was ever close to being dangerous as in downing the aircraft even with a flimsy containment.

Modern people are just horrified of living, everything is so dangerous, until I get a man purse I will not live my life in fear.

Topic: RE: FAA Grounds 787, Part 10
Username: par13del
Posted 2013-02-23 04:59:49 and read 6124 times.

Quoting Braybuddy (Reply 206):
I'd say it's more to to with the fact we are living in a time when higher and higher saftey standards are not only expected, they are the rule, which may be tough for the manufacturers, but can only be good for passengers.

I think it is more of a CYA to be honest, the improper wiring should have been discovered on both sides - user and OEM-, Boeing probably knew that with their electric plane users would be inclined to use the battery more thus running them down, I'm betting that there was some fine print on the issue. When you look at the number of failures of products the world over prevention (increased inspections) has taken a back seat to once a failure has occured, ensure that it never happens again by running the company out of business and putting punitive damages on the industry in the hope that it does not occur again, question is, in this day and age with all the technology available to us, is punitive damages the best way to prevent an accident tomorrow after a failure today versus more inspections two days prior to prevent the failure?
At the end of the day it is all about money, the legal industry has a vast number of lawyers ready and willing to work, inspection jobs on the other hand are long, booring, mostly uneventful, no praise or media attention, nothing spectacular when an item is discovered during maintenance and corrected, versus the worldwide spectacle when a failure occurs.
Look at the current horse meat fiasco, how many inspections in how many countries failed, do we not have measures in place to catch these thing before the get into the food supply? An example of the principle I'm talking about not to initiate a discussion off thread topic.

I would love to know if ANA and JAL reported the multiple battery failures to Boeing, does the battery OEM have to report to Boeing how many replacements / recharges that they perform, it can very well be that Boeing put improved battery functionality on the punch list way below the other pressing items such as gettign more a/c out the door. No different than when they boosted production of the 737 and ran into Q/A problems, the issue was not new technology then and I suspect it is not now, the properties of the mix in the battery are well know, indeed the measures put in place to accomodate them are extraordinary and shows that they know what they were / are dealing with.

Topic: RE: FAA Grounds 787, Part 10
Username: tharanga
Posted 2013-02-23 05:42:11 and read 5962 times.

In a hazardous scenario, you want both prevention and containment in your design. If the failure could be happening at a relatively high rate, I'm not sure what the FAA and NTSB will have to say about a strategy that is primarily focused on containment.

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-23 06:13:11 and read 5900 times.

Quoting PW100 (Reply 200):

The Nr.1 reason FAA issued the AD (which in effect grounded the 787 fleet) was the fact that Boeing had earlier claimed/demonstrated to a satisfactory level in the design certification, that such an event (battery thermal runaway) would happen less than once in a million hours. Once such an event happened twice in 50,000 hours, or less than two weeks apart, the whole certification basis of the 787 Type Certificate fell away, and the FAA had no other option.

Basically, the AD says Boeing has to redo this part of the design certification, and demonstrate how they will meet their earlier claims, and more importantly, how they can prove their assumptions. And you can count on it that this time there will be a lot more scrutiny than the first time around, when Boeing had a significant level of “delegated authority” to sort of self-demonstrate that the design met certification standards.

Excellent summation!

I'm still having a hard time understanding how Boeing will demonstrate their claims for the entire system given the root cause for the single cell failures is still not known and that it provides data points that will undermine their claims.

Quoting sweair (Reply 204):
I still think they aim to change the battery chemistry, but that will be a longer term fix, it will need to be re certified and will take more than a year at least.

When that new battery is ready and certified it will be retrofitted to all 787s flying. Until B comes out publicly saying a modified box is the ONLY fix, I will believe it, everything else is just guessing and rumours.

As above, we have a claim of 'no plan B' being attributed to unnamed Boeing insiders. Clearly to me that is corporate spin, intended to insure that the replacement battery idea gets no traction.

Quoting scbriml (Reply 205):
The Japanese investigators' findings are somewhat worrying - suggesting a failure of Q&A at Boeing in the rush to get 787s to the customers after all the delays.

Personally, I'm thinking that's normal teething problems for a new airplane. There always are areas where failures occur, and simple issues like paint getting into a place it should not, or insufficient glue on a window, inevitably occur and get sorted pretty quickly.

Topic: RE: FAA Grounds 787, Part 10
Username: cornutt
Posted 2013-02-23 08:46:26 and read 5479 times.

Quoting tharanga (Reply 211):
In a hazardous scenario, you want both prevention and containment in your design. If the failure could be happening at a relatively high rate, I'm not sure what the FAA and NTSB will have to say about a strategy that is primarily focused on containment.

Well, you go back to the fault tree analysis. One possible approach is to make a worst-case assumption that a cell will fail on every flight, and go from there. Test the containment and venting by setting fires in it, with something that has equivalent energy to a runaway cell plus a safety margin. (Thermite, maybe?) Figure out how much energy above the design maximum it takes to cause a containment failure. From there, the materials boffins can figure out a good estimate of the probability of a containment with a real battery. If it meets the 10^-9 standard, and the evidence from analysis and testing backs that up, the FAA has to approve it. I don't know if this is the approach Boeing is actually using, but it's one possible approach.

Topic: RE: FAA Grounds 787, Part 10
Username: sweair
Posted 2013-02-23 10:22:04 and read 5175 times.

Quoting Revelation (Reply 212):
As above, we have a claim of 'no plan B' being attributed to unnamed Boeing insiders. Clearly to me that is corporate spin, intended to insure that the replacement battery idea gets no traction.

That would be a very stupid decision of Boeing for sure, they have all eyes watching them and as you have seen huge numbers of anti Boeing posters shunning them daily.

I think after all the mess that the 787 project has been so far they need to take the right path this time, over do it on the safe side.

Media is clearly in for a spin, not that they are Airbus fanboys, they try to sell news. Every hiccup will be blown out of proportion if it is about the 787 in the future. Remember how the A380 had its share of media spin and excrement?

The most vocal people are sadly often the least informed and knowledgeable. Yes things were better in the old days, news did not travel as fast and media storms was not as easy to create.

The 787 is a blueprint for the future of airliners, someone had to take the step for development to move forward, although with a bit of pain. But no one will question bleed-less in 20 years time, I am sure, the progression did not end in the 60´s.

I for one shun the media and people that get off by shoveling crap for fun and pleasure.

Topic: RE: FAA Grounds 787, Part 10
Username: rcair1
Posted 2013-02-23 10:48:22 and read 5072 times.

Quoting Revelation (Reply 169):
Indeed, but it's not clear to me that this is sufficient.
Quoting Revelation (Reply 190):
I agree, but I'm concerned that it seems the root cause and the probability of failure of the individual cells is not well understood, while we see the rush towards the financially prudent course of action. Boeing could easily find that the root cause rears its ugly head again shortly after implementing the proposed changes and find themselves wishing that they paid more attention to Plan B, but hey, big money's on the line so it seems we're going to go down the expedient path first...

I'm quite sure Boeing is also concerned that the root cause is not determined. It would always be nice to have full root cause understanding of any issue - but that is not reality. It is much like a visit to your doctor. Often we do not know the root cause of an illness - so we treat the symptoms while trying to find it. We do not wait for the root cause to be found before we treat the symptoms. In this case I'm quite sure there are efforts to understand the root cause as well as treat the result of a failure in a way to preserves safety.

Also - words matter. They way you wrote the paragraph illustrates a bias, not a factual statement - that is fine. Opinions are well expressed. However, you could write the same paragraph in a way that does not imply or predicate a lack of care for safety.

Boeing and the airlines needing the 787 are businesses. It is indeed the 'financially' prudent path to work on a solution that assures safety and gets the a/c in the air. It was not built to be pretty sitting on the ground. It would not be financially prudent to sit twiddling thumbs while root cause analysis, which may or may not ever be established, goes on and on. The word "rush" is a value statement. It often means to hasten or work without quality - 'rushed' work is poor work. Another word that may not be so negatively laden is 'quickly'. Boeing is working quickly to find a solution.

And in fact, what would you expect them to do - work slowly?

Indeed - there is a risk in working quickly, with imperfect knowledge, toward a solution that you may find is not optimal from a long term perspective. It may 'cost less' to design the 'correct' fix now, if you knew it, and if you ignore the cost of lost business to the airlines and Boeing. They are risking the cost of design work that may be short lived or have to be revised. That happens all the time in engineering. You evaluate the cost/benefit/risk ratio and do what makes prudent financial sense. BTW - putting dangerous a/c in the air also has financial cost.

What we need to do is make sure that Boeings 'quick' work is also 'quality' work - they are not exclusive characteristics. That is the FAA's job.

Quoting BoeingVista (Reply 191):
The battery supports emergency functions in case of other failures so you cannot say that battery failures are of no concern as long as they are physically contained.

The battery only supports emergency functions when both engines have failed, and only while the APU and/or RAT deploys. The only case where you would need the battery for extended time would be if all engines and APU and RAT fail. Even the gimli glider and the more recent cases with fuel starvation in Pacific and bird strike in NY did not cause that. Gimli glider and the A330 in the Pacific had Rats. The A320 in the river had an APU. None were running on batteries for more than seconds.

Quoting 7BOEING7 (Reply 194):
The only thing that the battery would support for more than a few seconds is the brakes which means you may not stop at the end of the runway.

The battery would run the pilot flight instruments and computers - which is what it is intended to run - for more than a few seconds. But it's design purpose is to run it for minutes till other sources come up.

Quoting PW100 (Reply 200):
however you may INCREASE the single cell failure (if for all else equal),

That presupposes that a failure is _caused_ by overheating the cell for a non-runaway reason, i.e., in normal operation. In essence, supposing that the spacing/intra-cell insulation will cause the individual cells to run so dangerously hot in normal operation to cause a cell runaway. I'm quite sure that the design includes heat flow modeling such that the battery cells will not overheat in normal operation. Recall - the thermal load is identical, in normal operation, with or without the spacing. The heat sink - which is the insulation/box - is larger in the re-design. Of course, the head flow (conduction) may be quite different - so you have to account for that in the design. I'm 100% sure they are considering that.

Again - what they are doing is REDUCING THE FUEL LOAD by limiting cell runaway induced heating to 1 cell. In essence, the fuel is reduced to 1/8th the current battery because the design prevents a runaway/burning cell from causing the same issue in other cells.

I see no reason that isolating the cells would cause more failures if the design is done correctly.

Quoting par13del (Reply 210):
Boeing probably knew that with their electric plane users would be inclined to use the battery more thus running them down,

No - they knew the plane uses more electricity - why do you think it has bigger batteries? But that battery size is intended to support normal operations for the load the plane has. The cases where the battery is over discharged are when the plane is sitting on the ground - not hooked up to shortline - and powered up for some reason. From towing to cleaning.

Quoting par13del (Reply 210):
I would love to know if ANA and JAL reported the multiple battery failures to Boeing,

Of course they did. First of all - I would not be surprised if the replaced batteries were some type of warranty case in many instances. Second - they can probably only obtain replacements from Boeing.

[Edited 2013-02-23 10:52:18]

Topic: RE: FAA Grounds 787, Part 10
Username: sweair
Posted 2013-02-23 11:22:14 and read 4947 times.

Quoting rcair1 (Reply 215):

Thank you, a sober voice in the wild jungle here. People need to cool down and think for themselves IMO.

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-23 11:36:32 and read 4888 times.

Quoting rcair1 (Reply 215):
Quoting 7BOEING7 (Reply 194):The only thing that the battery would support for more than a few seconds is the brakes which means you may not stop at the end of the runway.

The battery would run the pilot flight instruments and computers - which is what it is intended to run - for more than a few seconds. But it's design purpose is to run it for minutes till other sources come up.

Assuming all four engines generators trip off, the Main battery takes over the Captain's instruments--within 30 seconds the RAT deploys and takes over--end of story, the Main battery is done. If the APU started automatically as it should, it will be online providing electrical power about 30 seconds later. If the APU doesn't start the Main battery will be used for braking after you land.

In flight the Main battery is there to transition the essential instruments from one power source to another. Even if the RAT doesn't deploy the APU should be online within about a minute. The 787 Main battery, or that of any other large airliner, is not meant to get the airplane back to the ground safely, most will be dead within 20-30 minutes if not sooner. After that it gets very dark.

Topic: RE: FAA Grounds 787, Part 10
Username: kanban
Posted 2013-02-23 12:21:09 and read 4752 times.

Quoting rcair1 (Reply 215):
I would not be surprised if the replaced batteries were some type of warranty case in many instances. Second - they can probably only obtain replacements from Boeing.

The batteries are vendor design and therefore procurable directly from the vendor as an LRU.

not seeing the assembly plan it;s hard to say which supplier.. i.e. does Yuasa install the batteries in the containment box and hook up all the wiring, or a second supplier like Thales?

Although I don't think we know how many were actual failures versus those drawn down too far to allow in plane recharging.

Topic: RE: FAA Grounds 787, Part 10
Username: tharanga
Posted 2013-02-23 12:31:17 and read 4719 times.

Quoting rcair1 (Reply 215):
It is much like a visit to your doctor. Often we do not know the root cause of an illness - so we treat the symptoms while trying to find it.

I don't disagree with other things you said, but I have to protest here - this is an extremely strained and ultimately meaningless analogy. Medicine is not a good source of analogies for engineering, in this sense.

The process of investigating the fault is inherently different between medicine and engineering - the engineer has many more tools and methods at his disposal, and the human body is much more complicated and difficult to understand. And the human will obviously choose to go on living until the doctor comes up with a root cause, and the human will often recover without any root cause being identified. In engineering though, you have a very different choice - do you keep operating or selling the machine, while it is still failing for reasons you haven't identified yet.

Topic: RE: FAA Grounds 787, Part 10
Username: Revelation
Posted 2013-02-23 12:54:28 and read 4646 times.

Quoting rcair1 (Reply 215):
I'm quite sure Boeing is also concerned that the root cause is not determined. It would always be nice to have full root cause understanding of any issue - but that is not reality. It is much like a visit to your doctor. Often we do not know the root cause of an illness - so we treat the symptoms while trying to find it. We do not wait for the root cause to be found before we treat the symptoms.

Yes, it's true, but the doctors also work by the "cause no harm" principal so to extend the analogy, there's no mandate for the 787 to fly if it "causes harm", the world will get on fine without it in the mean time even if this is inconvenient to various stakeholders.

Quoting rcair1 (Reply 215):
In this case I'm quite sure there are efforts to understand the root cause as well as treat the result of a failure in a way to preserves safety.

Yes, I'm sure there are. The context of my thoughts if not my writing is the press reports of statements being made allegedly by multiple Boeing insiders that there is no "Plan B". In my mind those statements seem to be aimed at closing down any discussion of a new battery option. I can't see any purpose for them otherwise.

Quoting rcair1 (Reply 215):
Also - words matter. They way you wrote the paragraph illustrates a bias, not a factual statement - that is fine. Opinions are well expressed. However, you could write the same paragraph in a way that does not imply or predicate a lack of care for safety.

Words matter, as do their context. In this case, it's an internet discussion forum where I'm stating a concern and using a hypothetical to illustrate it and further the discussion.

As for bias, I suppose by expressing a concern I can be considered to be biased, but given we don't have many facts to go on, one can also consider those to not have similar concenrs to be biased, albeit with a different bias.

Quoting rcair1 (Reply 215):
Boeing and the airlines needing the 787 are businesses. It is indeed the 'financially' prudent path to work on a solution that assures safety and gets the a/c in the air. It was not built to be pretty sitting on the ground. It would not be financially prudent to sit twiddling thumbs while root cause analysis, which may or may not ever be established, goes on and on. The word "rush" is a value statement. It often means to hasten or work without quality - 'rushed' work is poor work. Another word that may not be so negatively laden is 'quickly'. Boeing is working quickly to find a solution.

I'm fine with either word, it doesn't change what I'm trying to say.

Quoting rcair1 (Reply 215):
What we need to do is make sure that Boeings 'quick' work is also 'quality' work - they are not exclusive characteristics. That is the FAA's job.

Indeed, and as above, it'll be interesting to see how that can be done in the context of the known failures.

The descriptions we have of Boeing's plan don't have much discussion of what is thought to be the most likely root cause, metal shards, and what can or should be done to address that. Note the plan may address that, all I'm saying is the information being made public at this point doesn't seem to address that.

Quoting rcair1 (Reply 215):
The heat sink - which is the insulation/box - is larger in the re-design. Of course, the head flow (conduction) may be quite different - so you have to account for that in the design. I'm 100% sure they are considering that.

Good point. I'm sure it's being considered and analyzed. It'll be interesting if Boeing and/or NTSB and/or FAA will communicate these kinds of technical details presuming this design goes forward, in an effort to win public confidence.

Topic: RE: FAA Grounds 787, Part 10
Username: alfablue
Posted 2013-02-23 13:28:01 and read 4533 times.

Quoting cornutt (Reply 201):
The one concern is that the engines and APU are subject to a common-cause failure: fuel exhaustion. I could see a MEL provision that you could fly without the main battery provided that extra fuel is carried.

There are two cases of fuel starvation incidents. On approach or in cruise. In first category you can put UA DC-8, Avianca B707 and even BA B777 accidents all ending in the hull loss. In the later category you find the Gimli glider and Air Transat A330 (I come back to that later) which happened in cruise and ended in successful emergency landings, however both times without the possibility to start the APU due to real fuel starvation. Extra fuel would have had no effect on neither of those two incidents.

Quoting 7BOEING7 (Reply 202):
The MEL as well as Emergency Checklists are not predicated on multiple failures.

Not true. On the QRH for sure you find dual hydraulic loss and dual engine loss emergency procedures.

Quoting rcair1 (Reply 215):
It is much like a visit to your doctor. Often we do not know the root cause of an illness

it only affects you and not 220 fellow travellers in a carbon tube over the Pacific

Quoting rcair1 (Reply 215):
Gimli glider and the A330 in the Pacific had Rats. The A320 in the river had an APU. None were running on batteries for more than seconds.

And by design the RAT's need airflow which latest at roll out but sometimes at gear down will switch of the RAT and force to fly on battery. For sure the RAT can not provide braking power (electric, hydraulic, whatever).

Coming back to the Gimli glider and the Air Transat incident (Azores, Atlantic). Calculate the chances of 2 airlines from the same country experiencing a somehow similar incident (both in a way caused by technical defects). That should make anyone doubt statistics.

I will give you another example of statistics. How likely is it that an Airline manages to crash an airframe for the first time with PAX on board ending in a complete hull loss before others do and that for four times and all from the same production facility (Toulouse) and all having the same flight control system (fly by wire). AF managed to crash the first Airbus A320, the first Concorde, the first A340 and last but not least the first A330. If you add the little incident in JFK to the list (even though no hull loss but interesting nevertheless) it should now really make you rethink how statistics can bite your ass.

My point is that a failure chain leading to a hull loss is usually very complex and that the unlikely happens surprisingly often and thats why known failures need to be mitigated or eliminated. I don't see a huge improvement by adding ceramic separators and a better containment/venting system if the underlying failure rate is not tackled. Its doctoring on symptoms as previously mentioned but not eliminating the sickness.


alfaBlue

[Edited 2013-02-23 13:30:48]

Topic: RE: FAA Grounds 787, Part 10
Username: Wisdom
Posted 2013-02-23 13:44:16 and read 4467 times.

Reading some posts here, I see that there is a huge misconception on the role of the battery on the aircraft.
The battery's role is not to fill gaps during short periods of transitions between power sources.

The battery system and as it is called, the essential bus bar system powers essential/vital systems required to maintain safe flight in case of a major ELECTRICAL malfunction.

For ETOPS, this is of great significance as it's imperative that pilots be able to maintain stable flight and navigation to the closest airport in case of an electrical malfunction, eventually followed by an engine failure at the most critical moment of an ETOPS flight.

ETOPS, under the FAA defintion, unlike what many think, is not only a twin engine thingy, it relates to all the essential systems of an aircraft that pose a threat to an aircraft when diversion time becomes a factor in the outcome. In EU-OPS, the difference is made between ETOPS for twins and LROPS for 3-4 engined aircraft.

ETOPS and LROPS define standards of operations based on reliability of systems, procedures and even personnel essential for safe flight, wherever the safe outcome of incidents or failures can be affected by the diversion time to the closest suitable landing airport.

The battery operates essential thingies of last resort, such as standby instruments and usually a single display that can be switched between PFD/ND. It operates DC pumps of essential hydraulic systems in case of a total AC system failure and the RAT fails to activate or is deactivated by other systems or the flight crew.

The RAT is tested during maintenance checks, but it has its own problems. The hydraulic pump/generators that it operates could fail too, and if you've ever tested one, you'd know that the RAT is not something that you would like to rely on. It makes a huge rattling noise, has very unstable RPM's even in a test configuration, the deploying mechanism could get stuck, ice formation, etc...

[Edited 2013-02-23 14:10:05]

Topic: RE: FAA Grounds 787, Part 10
Username: PlanesNTrains
Posted 2013-02-23 13:59:23 and read 4384 times.

Quoting ServantLeader (Reply 176):
The 787 program has been plagued with problems since 2008 when delivery dates first started to slip -- that's a 5 year run of being behind the curve and screams of a denial modus operendi -- McNerney should have been fired circa 2011 for this pitiful performance, but since he is both CEO and COB, he is in the enviable position of being able to throw others under the bus.

Yawn.

Quoting sweair (Reply 216):
Thank you, a sober voice in the wild jungle here. People need to cool down and think for themselves IMO.

Just because someone disagrees with you doesn't mean that they are not thinking for themselves. In fact, it might mean quite the opposite.

-Dave

Topic: RE: FAA Grounds 787, Part 10
Username: rcair1
Posted 2013-02-23 14:10:34 and read 4339 times.

Quoting tharanga (Reply 219):
I don't disagree with other things you said, but I have to protest here - this is an extremely strained and ultimately meaningless analogy. Medicine is not a good source of analogies for engineering, in this sense.

As both an engineer and an emergency medical responder I'm well versed in the differences in the 2 fields/approaches.

It is interesting that engineers who have left engineering and gone into medicine are often considered to be the best diagnosticians. However - since all analogies are suspect and rarely will convince somebody who has a different opinion, it really does not matter too much. Either the analogy will allow somebody to learn and draw a conclusion - or not. They are offered in that sense.

Quoting alfablue (Reply 221):
it only affects you and not 220 fellow travelers in a carbon tube over the Pacific

220 patients then. And, if you consider the process of approving drugs for people - and the analog of certifying the plane, we are talking very similar instances. I've not done the math, but I suspect your risk of a serious side effect from some medications is far more than the danger to passengers on modern aircraft resulting from certification failures.

But - isn't it interesting that this discussion has absolutely nothing to do with 787 batteries - it is more about people battering...  

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-23 14:34:17 and read 4237 times.

Quoting alfablue (Reply 221):
Quoting 7BOEING7 (Reply 202):The MEL as well as Emergency Checklists are not predicated on multiple failures.
Not true. On the QRH for sure you find dual hydraulic loss and dual engine loss emergency procedures.

True, I guess I should have been more specific. Multiple engine failures (up to 4) are covered because they have in fact happened as well as multiple hydraulic failures (up to 2) but even on a 747 with 4 hydraulic systems the checklist only covers 2.

Quoting Wisdom (Reply 222):
Reading some posts here, I see that there is a huge misconception on the role of the battery on the aircraft.
The battery's role is not to fill gaps during short periods of transitions between power sources.

True and not true. If you're down to the battery in any modern airliner you only have a limited amount of time (30 to 60 minutes depending on the battery and its condition) before the battery is dead and the cockpit goes dark--you better be VFR with a field in sight. Planes like the 777 and 787 have multiple generators (4) plus the APU and the RAT to insure you never end up flying around with a battery only. In both the 777 and 787 the Main battery supplies power with loss of all 4 engine generators until the RAT drops which is about 30 seconds--after that its done. The big drain on the 787 battery in flight is to supply backup power for the brakes because if you're on RAT power only, that drops off at about 70+/- knots on rollout.

Topic: RE: FAA Grounds 787, Part 10
Username: alfablue
Posted 2013-02-23 15:13:14 and read 4110 times.

Quoting rcair1 (Reply 224):
220 patients then. And, if you consider the process of approving drugs for people - and the analog of certifying the plane, we are talking very similar instances.

They are not as you participate in a clinical study voluntarily and actually you sign a consent form. If a pill does not perform after market introduction or cause unforeseen side effects it actually gets grounded too (forever I might add so lets hope Boeing has more luck with the 787). So what would the logical choice be? A consent form at check in were you sign off on the risk to fly on an aircraft with an essential system showing a below certification standard failure rate?

Coming back to the 787, I think the authorities have put the hurdle high up with that bold statement of 1000% safe and underlying cause of the failures - Boeing has not addressed those issues and the FAA statement says that too.

I have found an interesting accounting article though -- it shows more detail of the underlying financial mess the 787 threatens to become.

http://edmondsbeacon.villagesoup.com/p/the-787-financial-crisis/965997

alfaBlue

Topic: RE: FAA Grounds 787, Part 10
Username: PW100
Posted 2013-02-23 15:48:02 and read 4002 times.

Quoting rcair1 (Reply 215):
Again - what they are doing is REDUCING THE FUEL LOAD by limiting cell runaway induced heating to 1 cell. In essence, the fuel is reduced to 1/8th the current battery because the design prevents a runaway/burning cell from causing the same issue in other cells.

I see no reason that isolating the cells would cause more failures if the design is done correctly.

I fully agree with what you're saying about reducing the fuel load. I also agree that if done correctly (which leaves huge room for discussion . . . ) insulation should not cause more failures of the total battery pack, or even of individual cells.

The single cell failure was brought up in the post I was referring to, and I was merely trying to point out that the solution of insulation MAY induce the opposite effect with respect to the single cell failure rate.

Applying insulation will by definition increase individual cell temperatures at the moment they go for whatever reason above their normal operating temperature. If a single cell increases temperature, but not yet to the extent that it will go into thermal runaway (perhaps by virtue of the BMS stepping in in a timely fashion), shedding some heat energy to the surrounding might help prevent it from reaching that critical temperature. This might buy just a little extra time for the BMS to intervene, and that intervention could also protect the adjacent cells that are now assuming some heat from the critical cell. Adding insulation will much better protect the adjacent cells, but can still have a negative effect on the initiating critical cell.

Complicating factor might be that the individual cells are pretty big, as claimed earlier by Elon Musk, and the BMS might not be able to oversee all temperature zones in the individual cell.

Also worthy noting is that out of 16 cells total between the two burnt AJL and ANA batteries, only a handful of them actually did go into full thermal runaway. So from that point of view, the extra insulation was not really required to protect the other cells. Perhaps that was because they were able to dissipate sufficient heat to keep them under the critical temperature, or perhaps the BMS was more effective on the non-critical cells.

Again, this all was just a reaction to the an earlier post, that suggested/claimed that Boeing would/could/should demonstrate that even a single cell thermal runaway would not occur (to the extent of less than once in a million hours).

Quoting Wisdom (Reply 222):
Reading some posts here, I see that there is a huge misconception on the role of the battery on the aircraft. The battery's role is not to fill gaps during short periods of transitions between power sources.

The battery system and as it is called, the essential bus bar system powers essential/vital systems required to maintain safe flight in case of a major ELECTRICAL malfunction.

For ETOPS, this is of great significance as it's imperative that pilots be able to maintain stable flight and navigation to the closest airport in case of an electrical malfunction, eventually followed by an engine failure at the most critical moment of an ETOPS flight

I'm not sure I understand what you are saying. Surely you can't be suggesting that a battery would power all critical systems for the diversion time to the closest suitable landing airport. For ETOPS 330, that would mean that the main battery would power all critical systems for 5.5 hours.

It requires only a single generator (probably for less than 50% of it's normal capacity) of one engine, or the APU, or even the RAT. As soon as that power is on-line, the battery will stop feeding the essential bus bar.
To me that sounds as the main battery is only required for transition between power sources (on the essential bus bar, as you named it).

Also, I'm at total loss why you stress that ETOPS applies not only to twin engined airframes. I have not seen anyone doubt that in this thread, and I fail to see the relevance to this thread.


Rgds,
PW100

Topic: RE: FAA Grounds 787, Part 10
Username: alfablue
Posted 2013-02-23 16:02:32 and read 3961 times.

Quoting PW100 (Reply 227):
Also, I'm at total loss why you stress that ETOPS applies not only to twin engined airframes. I have not seen anyone doubt that in this thread, and I fail to see the relevance to this thread.

I would say ETOPS is among the biggest issues the 787 faces. Its quite relevant to this threat as we talk a lot about certification and probabilities. The battery and battery buses are so deeply integrated that they certainly play a role in the ETOPS/LROPS certification process. Wisdom didn't imply that the aircraft has to be able to fly 5.5 hrs on batteries but he raised a valid future concern for Boeing - Will the Dreamliner maintain its ETOPS certificate?

http://blogs.crikey.com.au/planetalk...l-it-restrict-787-etops-approvals/

http://www.thedailybeast.com/article...9/boeing-s-dashed-flight-plan.html

from the article:

Nor has the FAA, pre-occupied by the battery investigation, discussed the future of the 787’s certification for long haul flights. That remains moot while it mandates that 787s remain grounded.

But in view of what has so far emerged, the agency’s resistance to Boeing’s desire to accelerate the rating to 330 minutes has likely hardened. As it is, the key question for airlines now is not simply, when can we get this airplane back in the air, but how far can it fly?

alfaBlue

[Edited 2013-02-23 16:07:39]

Topic: RE: FAA Grounds 787, Part 10
Username: Wisdom
Posted 2013-02-23 17:55:33 and read 3699 times.

Quoting PW100 (Reply 227):
I'm not sure I understand what you are saying. Surely you can't be suggesting that a battery would power all critical systems for the diversion time to the closest suitable landing airport. For ETOPS 330, that would mean that the main battery would power all critical systems for 5.5 hours.

It requires only a single generator (probably for less than 50% of it's normal capacity) of one engine, or the APU, or even the RAT. As soon as that power is on-line, the battery will stop feeding the essential bus bar.
To me that sounds as the main battery is only required for transition between power sources (on the essential bus bar, as you named it).

Also, I'm at total loss why you stress that ETOPS applies not only to twin engined airframes. I have not seen anyone doubt that in this thread, and I fail to see the relevance to this thread.

No that's not what a battery is for. The battery is supposed to hold up critical systems for the duration of the diversion in case of an electrical failure. That is standby instruments, a navigation display and if possible, DC pumps to charge the accumulators (electric braking in the 787's case).

5.5 hours is tight on a 2kwh battery but a small LCD screen is around 20 watts, the ADIRS should be around 150 watts total and your VHF radio's 30 watt. All in all, 300 watts is probably what it takes, I don't think Boeing could go around installing a battery that would not be able to support critical systems on its own during an ETOPS diversion.

Braking doesn't take as much as one would think, once the brakes are engaged, there is barely any power required unless released and reapplied.

An APU takes 10 seconds to fire-up, if other gens are online you don't need the main battery to power anything at all, I don't see why you would fly with any of the 4 engine gens offline on something as hungry on electricity as the 787. So even if you lose an engine, you'd still have 2 gens providing electricity to the essential busbars as their first priority.

As you see, there is no stop-gap role for the battery to play.

That a battery is there to fill gaps is a misconception of people who have never had an aircraft's electrical schematic in their hands. The DC system is an emergency back-up for the case that the entire AC system goes haywire, nothing to do with single gens or even two gens failing.

As to the RAT, if it gets that far, ie no generation at all, a battery is a welcome addition. The RAT will have its hands full providing power to the hydraulics, if it works that is. The RAT is, like the battery, a system of last resort. However, the rat is not something that you use on a daily basis so you don't know if it works until it deploys and starts feeding your systems.

Your battery is your source of power of last resort, the only thing that you know won't let you down even when you're having a very, very bad day. In light of that, a good containment is not a sufficient fix, the battery needs to be reliable.

[Edited 2013-02-23 17:59:36]

Topic: RE: FAA Grounds 787, Part 10
Username: 7BOEING7
Posted 2013-02-23 19:17:02 and read 3535 times.

[quote=Wisdom,reply=229]No that's not what a battery is for. The battery is supposed to hold up critical systems for the duration of the diversion in case of an electrical failure. quote]

WISDOM, please find a 777 or 787 Flight Crew Operations Manual and do some reading. The Main battery only powers the essential flight instruments when nothing else is available i.e., after all four generators go down and the RAT hasn't come up to speed. The 787 FCOM states the "The main battery provides power for: the Captain's flight instruments (energizes essential instruments until RAT deployment)". The main buses power the DC bus until you lose the main bus then the battery takes over, at least on all the Boeing airplanes. Do to its lack of redundancy the 737 had/has an optional larger battery but that only buys you an hour and a half (?) at best.

FYI the APU on the 787 and 777 takes over a minute to come up and online in flight.

Topic: RE: FAA Grounds 787, Part 10
Username: cornutt
Posted 2013-02-23 19:40:41 and read 3491 times.

Quoting alfablue (Reply 221):
I don't see a huge improvement by adding ceramic separators and a better containment/venting system if the underlying failure rate is not tackled.

But that's exactly how blade failures in engines are handled. No certification authority requires that an engine design be 100% free from ever throwing a blade, nor does anyone know how to build such an engine. Those failures are handled by building containment into the engine, and everyone accepts that approach as long as the fault tree numbers meet the certification standard.

Topic: RE: FAA Grounds 787, Part 10
Username: PW100
Posted 2013-02-23 20:26:13 and read 3393 times.

Quoting alfablue (Reply 228):
I would say ETOPS is among the biggest issues the 787 faces . . . .

I don't think I have disputed that. It certainly was not my intention.

The poster was stressing that ETOPS did not only apply to twin-engined airframes but to all airframes (three and fout holers as well), and that THAT was being overlooked by a lot of folks in these threads. THAT, I did no see in this thread, and THAT I think has no relevance in this thread.

Which does not mean that ETOPS is not an issue with the 787. It's one of the safest bets that once the 787 gets back to the air, it will not have ETOPS 330, and ETOPS 180 might also be a challenge.

Rgds,
PW100

Topic: RE: FAA Grounds 787, Part 10
Username: PW100
Posted 2013-02-23 20:56:39 and read 3346 times.

Sigh, I don't know where to start . . .


First you write that the battery will have to feed the critical systems for the full duration of the diversion:

Quoting Wisdom (Reply 229):
No that's not what a battery is for. The battery is supposed to hold up critical systems for the duration of the diversion in case of an electrical failure. That is standby instruments, a navigation display and if possible, DC pumps to charge the accumulators (electric braking in the 787's case).

5.5 hours is tight on a 2kwh battery

And then you state that the battery will only need to provide power for 10 seconds:

Quoting Wisdom (Reply 229):
An APU takes 10 seconds to fire-up, if other gens are online you don't need the main battery to power anything at all, I don't see why you would fly with any of the 4 engine gens offline on something as hungry on electricity as the 787. So even if you lose an engine, you'd still have 2 gens providing electricity to the essential busbars as their first priority

BTW How do you envision a 5.5 hr glide . . . ? You mean the aircraft will fly for 5.5 hrs without any electrical power generation?

As long as engines are running, you’re pretty much guaranteed to have at least one generator on-line**. If not, then there is the APU gen that will come on-line within a minute or so. If not, then there is the RAT-gen, which surely will provide more accumulated power than a battery can provide over a 5.5 hour period.

** Not to mention that as soon as one engine fails (or even one generator, I think) the APU will be started, which brings and additional two generators on-line.

Quoting Wisdom (Reply 229):
As to the RAT, if it gets that far, ie no generation at all, a battery is a welcome addition. The RAT will have its hands full providing power to the hydraulics, if it works that is. The RAT is, like the battery, a system of last resort. However, the rat is not something that you use on a daily basis so you don't know if it works until it deploys and starts feeding your systems

The RAT also drives a generator. I would tend to believe that there is a good reason Boeing added the weight of a RAT driven generator . . . And the RAT system is very simple, and thus pretty pretty reliable, I would expect.

So the APU and eventually the RAT will take care of your bad day. The battery will cover the delay in getting one of these on-line. And the battery will stop the aircraft at roll-out once airspeed drops below 60 knots or so - above that speed the RAT-gen still provides sufficient power for the electric brakes.

Quoting Wisdom (Reply 229):
Braking doesn't take as much as one would think, once the brakes are engaged, there is barely any power required unless released and reapplied

I find this interesting. I'm not disputing. It is just that I would expect that a significant force would be required to pull the brake discs together. Doing this electrically will require a significant current draw to generate the required EMF force. I did not expect that engaging the brakes will require more current than keeping them engaged.
I can see that what you are saying would apply to hydraulic actuation, but I did not expect that from electrical actuation. I would appreciate if you could provide more insight.

Rgds,
PW100


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