Sponsor Message:
Civil Aviation Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
FAA Grounds 787, Part 11  
User currently offline777ER From New Zealand, joined Dec 2003, 12114 posts, RR: 18
Posted (1 year 6 months 1 week 2 days 4 hours ago) and read 25999 times:
AIRLINERS.NET CREW
FORUM MODERATOR

Link to thread #10 FAA Grounds 787, Part 10 (by 777ER Feb 17 2013 in Civil Aviation)#menu209

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.

216 replies: All unread, showing first 25:
 
User currently offlinePW100 From Netherlands, joined Jan 2002, 2455 posts, RR: 12
Reply 1, posted (1 year 6 months 1 week 2 days 4 hours ago) and read 25996 times:

OK. Recap:

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.

Friday 22 Feb 2013 Boeing presented an action plan to the FAA:

Boeing remains tight-lipped about its proposed fix, but according to multiple sources, it includes:
• A stronger, sealed containment box enclosing the eight battery cells;
• A system of venting tubes that in case of an incident would channel any flammable vapors or liquids directly out of the airplane;
• Continuous monitoring of temperature and voltage of individual cells within the battery;
• Better thermal separation of the cells, with some barrier such as high-temperature glass inserted between them.


Good luck to Boeing, and hope to see many 787 contrailing the skies soon!



Immigration officer: "What's the purpose of your visit to the USA?" Spotter: "Shooting airliners with my Canon!"
User currently offlinePHX787 From Japan, joined Mar 2012, 7477 posts, RR: 18
Reply 2, posted (1 year 6 months 1 week 2 days 4 hours ago) and read 25967 times:

Ok I really would like to follow and contribute to this thread as much as I possibly can. I have a plethora of news that keeps getting posted on Japanese websites, but I find it quite difficult for me to post because of how quickly these threads get out of control. I want to second 777ER's post here, and I would like to add thread 7 and 8 went out of control to become a battle ground as well.

Quoting 777ER (Thread starter):
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.

We're 11 threads in with actually little progress into the fix, besides the "temporary" fix that B calls "permanent." Let's focus this time on keeping these things news-oriented. Here's something I see.....

Quoting PW100 (Reply 1):
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.

What is Boeing seeing with this fix?
What is this fix-- layman's terms?
How much testing will this require
When will the 787, then, get off the ground again?



次は、渋谷、渋谷。出口は、右側です。電車とホームの間は広く開いておりますので、足元に注意下さい。
User currently offlinegemuser From Australia, joined Nov 2003, 5641 posts, RR: 6
Reply 3, posted (1 year 6 months 1 week 2 days 3 hours ago) and read 25841 times:

Quoting PW100 (Reply 1):
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,

This is a gross exaggeration! The "whole basis ... Type Certification" did not fall away. It still stands and is valid. What did happen was the two events in 50,000 hours called in to question compliance with one of the special conditions, which have been discussed to death in these threads. That's why the AD was issued. The problem is NOT a threat to the type certification, just one item, out of thousands.
Of course that one item was enough for the FAA to issue a "before further flight" AD, which is their right & proper role.

Gemuser



DC23468910;B72172273373G73873H74374475275376377L77W;A319 320321332333343;BAe146;C402;DHC6;F27;L188;MD80MD85
User currently offlinesweair From Sweden, joined Nov 2011, 1821 posts, RR: 0
Reply 4, posted (1 year 6 months 1 week 2 days 2 hours ago) and read 25707 times:

What did the two events have in common? If we would venture on a guess? Prior to thermal runaway they were running the APU? Was there any drain on the batteries in both events?

User currently offlinejporterfi From United States of America, joined Feb 2012, 443 posts, RR: 0
Reply 5, posted (1 year 6 months 1 week 2 days ago) and read 25494 times:

Quoting PHX787 (Reply 2):
What is Boeing seeing with this fix?

I may be ridiculed for saying this, but I truly believe that Boeing thinks this fix (coupled with necessary modifications to it that the FAA requires before re-certifying the 787) is permanent. Therefore, I think that Boeing is seeing whether the fix will sufficiently contain any thermal runaway, and prevent is from damaging the aircraft outside of the containment box.

Quoting PHX787 (Reply 2):
What is this fix-- layman's terms?

Essentially it is a stronger containment box made out of steel or titanium, as well as a thicker layer of insulated separator (not sure what material) between the cells. I believe the idea is to keep any thermal runaway from spreading to multiple cells and/or out of the battery.

Quoting PHX787 (Reply 2):
How much testing will this require

Someone on another thread mentioned hte batteries would need to be tested to the point of failure, but I hardly see the point in that much testing. An interesting idea that was previously mentioned is conducting a test flight, then mid-flight, inducing thermal runaway in one cell of a battery and seeing if it spreads to other cells or outside of the containment box (most likely within a certain amount of time).

Quoting PHX787 (Reply 2):
When will the 787, then, get off the ground again?

I think it is far to early to tell. We at least need to wait and see if/when the FAA and NTSB approve Boeing's proposal before more educated speculation can commence.


User currently offlineAeroWesty From United States of America, joined Oct 2004, 20559 posts, RR: 62
Reply 6, posted (1 year 6 months 1 week 2 days ago) and read 25423 times:

Quoting jporterfi (Reply 5):
I think it is far to early to tell. We at least need to wait and see if/when the FAA and NTSB approve Boeing's proposal before more educated speculation can commence.

A lot of these questions are answered in the Seattle Times article linked above. In regards to testing and return to service, it notes a couple of interesting things:

Quote:

What’s unclear is how much testing the FAA will require to validate the safety of the revamped battery.

Barnett said the tests conducted on the batteries by Boeing during the original certification process — baking the battery in an oven, puncturing it with a nail, crushing it, and overcharging it — are standard industry tests but don’t reflect what typically happens when a battery fails due to an internal short circuit.

...

And the FAA will want thorough testing of Boeing’s fix, he said.

“The last thing the FAA can stand is to fast-track this and then have something else go wrong,” Hamilton said.

...

A further uncertainty, he said, is that 24 of the 50 Dreamliners that are grounded worldwide are operated by just two Japanese airlines.

Whatever the FAA decides, the Japan Transport Safety Board is expected to be conservative in allowing those jets to fly.



International Homo of Mystery
User currently offlineB777LRF From Luxembourg, joined Nov 2008, 1334 posts, RR: 3
Reply 7, posted (1 year 6 months 1 week 1 day 23 hours ago) and read 25272 times:

So what Boeing's essentially proposing is something along the lines of "We don't know what happened to the battery, so we can't stop it from happening again. If it does catch fire, here's a solid box to drop it in, a couple of vent tubes and a few extra lines in the QRH for the boys at the sharp end. Job jobbed, can we go back flying again please"?

The whole idea of "let 'er burn, containment will do" as the sole and final fix is utterly perplexing, runs contrary to everything the safety standards of aviation embrace, and should not be allowed to stand.

If the FAA has just a smidgen of testicular fortitude, they'll tell Boeing to sod off and come back when they've got a battery system to present that's no more liable to combustion than "industry best practice". Whether that can be done with Li-Ion, NiCad's or something else is besides the point. And if the FAA won't do it, one hopes there are other NAA's out there who won't be afraid to say "sorry, not on my watch" and thus scuttle this half-baked, non-conforming, abortion from taking flight.



From receips and radials over straight pipes to big fans - been there, done that, got the hearing defects to prove
User currently offlineXT6Wagon From United States of America, joined Feb 2007, 3399 posts, RR: 4
Reply 8, posted (1 year 6 months 1 week 1 day 22 hours ago) and read 25177 times:

Quoting B777LRF (Reply 7):
The whole idea of "let 'er burn, containment will do" as the sole and final fix is utterly perplexing, runs contrary to everything the safety standards of aviation embrace, and should not be allowed to stand.

no it isn't. Lots of things on an airplane are allowed to break. If we use your critera no aircraft would ever fly as engines break more than never. Lets be more blunt. The battery is a back up for *6* units any 2 of which keeps the plane fully powered as far as safety goes. The 4 generators on the engine would all have to offline in one very short event to keep the APU 2 generators from being online. In such a case the batteries would be needed as a bridge between main power system failure and APU start. We are getting into events that are extremely remote, and you can bet that any aircaft with a main battery failure would be diverting as soon as possible regardless of the cause of the failure.

So what Boeing is attempting to do is prove that only the battery would break in the case of thermal run-away. From my perspective they are already most of the way there as the current system clearly worked fine twice. So even better thermal management of the battery in thermal runaway coupled with external venting of the by-products is pretty much golden.


User currently offlineAngMoh From Singapore, joined Nov 2011, 485 posts, RR: 0
Reply 9, posted (1 year 6 months 1 week 1 day 22 hours ago) and read 25048 times:

Quoting XT6Wagon (Reply 8):
no it isn't. Lots of things on an airplane are allowed to break.

Yes they are allowed to break, but they are not allowed to go up in flames.

Quoting XT6Wagon (Reply 8):
Lets be more blunt. The battery is a back up for *6* units any 2 of which keeps the plane fully powered as far as safety goes. The 4 generators on the engine would all have to offline in one very short event to keep the APU 2 generators from being online. In such a case the batteries would be needed as a bridge between main power system failure and APU start.

The 787 did not get grounded because the batteries failed. The 787 got grounded because 2 batteries experienced thermal runaway at a rate significantly higher than predicted by the certification process. One resulted in a fire and in the other case the pilot made an emergency landing due to a suspected fire. Had they just failed to work, there would be no fire and no emergency landing and the 787 would not be grounded today.

Quoting XT6Wagon (Reply 8):
So what Boeing is attempting to do is prove that only the battery would break in the case of thermal run-away. From my perspective they are already most of the way there as the current system clearly worked fine twice. So even better thermal management of the battery in thermal runaway coupled with external venting of the by-products is pretty much golden.

Here I disagree strongly and even the FAA disagreed strongly in the Cessna Citation case. First thermal runaway should be extremely rare. Secondly, in the event it happens it should be harmless. And from my perspective, the current system did not work in both events. Boeing is not improving the thermal management as they admit they don't know what caused the thermal runaway. They only try to make the thermal runaway harmless. And here I think Boeing underestimates the degree that other parties will cover their butt. The FAA, being a government organisation, is not going to take any risks because they received enough criticism till now, and airlines are going to play it safe because they can not afford another smoking 787 in the news. Just look at how long it took for the media scrutiny the reduce after the QF32 incident: even today the day to day issues with A380s get blown up (see the Emirates "door blowout" news).


User currently offlineAA737-823 From United States of America, joined Mar 2000, 5774 posts, RR: 11
Reply 10, posted (1 year 6 months 1 week 1 day 22 hours ago) and read 25045 times:

Quoting XT6Wagon (Reply 8):
The battery is a back up for *6* units any 2 of which keeps the plane fully powered as far as safety goes.

Any one of those *6* units can be MEL'd; the battery cannot. Further, it is fully required to be in full health for ETOPS operations, so at that point, you've got an ETOPS airplane that can't fly target missions, and realistically can't leave the ground.

Quoting B777LRF (Reply 7):
The whole idea of "let 'er burn, containment will do" as the sole and final fix is utterly perplexing, runs contrary to everything the safety standards of aviation embrace, and should not be allowed to stand.

Agreed; consequently, as we can all agree that it is NOT in Boeing's best interest to pay the costs of lawsuits after a fiery 787 crash, I am hoping like you are that BoCo has another plan.

Quoting B777LRF (Reply 7):
If the FAA has just a smidgen of testicular fortitude, they'll tell Boeing to sod off and come back when they've got a battery system to present that's no more liable to combustion than "industry best practice".

The FAA exerts testicular fortitude when and where they wish. We've seen them over-punish some, while simultaneously under-punishing others. But it may be a moot point; in the linked article above, it's reported that the JTSB has no interest in permitting the airplanes into their airspace until the root cause is known and exhausted.


User currently offlinesankaps From United States of America, joined Jan 2008, 2255 posts, RR: 2
Reply 11, posted (1 year 6 months 1 week 1 day 22 hours ago) and read 25018 times:

Quoting XT6Wagon (Reply 8):
. From my perspective they are already most of the way there as the current system clearly worked fine twice.

Unfortunately your perspective is not shared by the airlines involved, the FAA, the NTSB, most external technical experts, or even by Boeing's CEO McNerney. And there have been 10 threads which try to explain why the current system did not "clearly work fine twice". A system that works fine does not result in the scenes we saw with both the JAL and ANA incidents.

In a nutshell Boeing has two things to fix: Significantly reduce the probability of batteries failing in this manner, and improve the containment when the battery does fail. What they have proposed thus far is for the latter; they still do not have a solution for the former, as no one yet knows what caused the batteries to fail.


User currently offlinemjoelnir From Iceland, joined Feb 2013, 1436 posts, RR: 2
Reply 12, posted (1 year 6 months 1 week 1 day 22 hours ago) and read 25009 times:

When a robust containment, I am not of the opinion the old one was working, vents directly outside, keeping flame, smoke and explosive gases from entering the e-bay there is one question left, what exactly is the function of the main battery in flight, can the B 787 live without it.

If it is only a backup for electrical generation, than I agree that electrical generation is pretty well covered, having two engines with four generators, apu and rat.

But somewhere in this thread, I am to lazy to find it, it was said that the main battery was a backup for the flight instruments in case of an electrical failure as opposed to a generating failure. That means electrical generation is okay, engines running, generators generating but some electrical fault is scrambling the electrics.


User currently offlineAndyEastMids From United Kingdom, joined Jan 2001, 1017 posts, RR: 2
Reply 13, posted (1 year 6 months 1 week 1 day 20 hours ago) and read 24808 times:

“...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,” said an FAA statement

To me this suggests that the FAA are not requiring Boeing to stop (or reduce the frequency of) batteries failing, but are only expecting Boeing to improve what happens when a battery does fail.


User currently offlineart From United Kingdom, joined Feb 2005, 3382 posts, RR: 1
Reply 14, posted (1 year 6 months 1 week 1 day 20 hours ago) and read 24736 times:

Quoting XT6Wagon (Reply 8):
So what Boeing is attempting to do is prove that only the battery would break in the case of thermal run-away. From my perspective they are already most of the way there as the current system clearly worked fine twice.

To me the point is that the frequency of failure appears to be higher than that allowed, even if containment worked perfectly.

Quoting AngMoh (Reply 9):
The 787 did not get grounded because the batteries failed. The 787 got grounded because 2 batteries experienced thermal runaway at a rate significantly higher than predicted by the certification process.

Concur with your statement.

Quoting sankaps (Reply 11):
In a nutshell Boeing has two things to fix: Significantly reduce the probability of batteries failing in this manner, and improve the containment when the battery does fail.

Concur with your statement.

I hope Boeing can come up with an acceptable battery system (probability of failure / containment performance in case of failure) without it taking many months. They have not been lucky with this aircraft (although if you can make your own luck they did a bad job of doing that - premature rollout for silly reasons etc).


User currently offlineasctty From United Kingdom, joined Dec 2008, 117 posts, RR: 0
Reply 15, posted (1 year 6 months 1 week 1 day 20 hours ago) and read 24429 times:

The thing for me is what is the purpose of the battery? If it is a safeguard against a failure of the normal electrical supply? What I have yet to see on any of these threads is what was the status of the battery that went on fire? Was is it on load, or was is it on stand-by? If it was on load did the pilots notice any loss of function? If it was on stand-by, lucky the pilots did not have to rely on it.
A containment will not fix the issue regarding the function of the battery. It will only stop the battery becoming another cause for a hazard, i.e. fire!
There are still many unanswered questions about this issue.


User currently offlineRheinbote From Germany, joined May 2006, 1968 posts, RR: 52
Reply 16, posted (1 year 6 months 1 week 1 day 19 hours ago) and read 24171 times:

Quoting mjoelnir (Reply 12):
But somewhere in this thread, I am to lazy to find it, it was said that the main battery was a backup for the flight instruments in case of an electrical failure as opposed to a generating failure.

The flight control electronics have their own dedicated back-up battery.


User currently offlineWisdom From , joined Dec 1969, posts, RR:
Reply 17, posted (1 year 6 months 1 week 1 day 19 hours ago) and read 23872 times:

Quoting XT6Wagon (Reply 8):
no it isn't. Lots of things on an airplane are allowed to break. If we use your critera no aircraft would ever fly as engines break more than never. Lets be more blunt. The battery is a back up for *6* units any 2 of which keeps the plane fully powered as far as safety goes. The 4 generators on the engine would all have to offline in one very short event to keep the APU 2 generators from being online.

This is not what you have the battery for. Batteries are not meant to be used as a transitionary power source.
When you lose one engine, you still have 2 gens and you start firing up the APU immediately (or the APU fires up automatically). You don't wait until the other engine quits and the probability of losing both engines is low (that's what she said... history says otherwise).


The battery is there to deal with a major electrical failure, such as one that could be caused by major short-circuiting, electrical arching, such as could be caused by a major lightning strike, maintenance error, FOD, etc.
These are situations wherein there is no power flowing from any generators, to the essential systems for flight, no matter whether the generators are or are not producing any power.

May I remind you that Boeing has had one similar incident with the 787 already, with the fire caused by FOD on the P100 panel, resulting in cascading electrical failures, and ended up with battery providing power to the essential busbar for the diversion.

Quoting PW100:
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.

See above.
Again, you're focusing too much on the engine failure scenario.

The battery is not there for an engine failure scenario that would result in partial loss of electrical generation, they are there as a back-up for a major main electrical system failure.

In an aircraft, wires run in bundles and are situated in places that are inaccessible or impossible to inspect. If such bundles chafe against a sharp edge, it could uncover insulation, start a major short-circuit or paired with moisture and Kapton even start an electrical fire that could cascade into multiple electrical failures, in the worst case scenario even a total loss of the AC electrical systems.

All this while all engines are running, and all gens are online (in reality the gens will automatically go on standby).

In such scenario, the RAT is not really useful and I'm not even sure that it would deploy (depends on individual aircraft type's architecture).

Remember that ETOPS ratings are diversion times at one engine cruise speeds/altitudes. So in most scenario's on conventional airliners where you have an electrical failure but still have engines, you would be less than 5.5 hours away from your diversion airport.

The only tricky thing about the B787 is that it runs the A/C and pressurisation on AC electricals. So as I said in the past weeks, a total AC electrical failure would require the B787 to fly a diversion (with both engines) at a low sustainable breathing altitude for the passengers of around 14000 feet, which will result in lower speed and higher fuel burn.

In light of this, I'm not sure that the one-engine out scenario would result in higher fuel consumption than the AC electricals failure scenario, I hope that Boeing and the FAA took that into consideration during certification.

Even worse would be a single engine failure with a total AC electricals failure.
You would need to fly on one engine at 14.000 feet, I hope that that is a scenario that they have taken into account during certification.

[Edited 2013-02-24 06:14:36]

User currently offlineWisdom From , joined Dec 1969, posts, RR:
Reply 18, posted (1 year 6 months 1 week 1 day 18 hours ago) and read 23645 times:

Regarding your question about electric braking:

Looking at the picture of the brake assembly (just google it), it looks to me like it's just the hydraulic pistons which press the rotors and stators together to create the braking effect, that have been replaced by electric actuators. Once the actuators are activated the power to maintain the m actuated should be minimal as most of the load will be absorbed by the threads of the screws of the actuator.

Be reminded that emergency braking usually activates only select brake assemblies, meaning that you don't have full control of braking/steering.

The UA497 is a recent event wherein a A320 lost all AC power due to an electric fire, they returned on the batteries and the RAT.
see http://avherald.com/h?article=43a6bc08

Even though the batteries didn't provide sufficient power for a completely controlled stop, everybody walked away.
Batteries are the electric back-up system of last resort, on which a pilot should be able to rely even on the worst of days.

That's what batteries are for.

[Edited 2013-02-24 06:39:35]

User currently offlineRevelation From United States of America, joined Feb 2005, 12465 posts, RR: 25
Reply 19, posted (1 year 6 months 1 week 1 day 18 hours ago) and read 23539 times:

Quoting PW100 (Reply 1):
Continuous monitoring of temperature and voltage of individual cells within the battery

Interesting how the word "monitoring" is used. In the last thread a poster was implying that the BMS could also take an individual cell offline, but I see no evidence of that in the public statements. The existing "special conditions" says the battery charger needs to be able to be disconnected from the battery but nothing about isolating an individual cell as far as I can determine.

Quoting jporterfi (Reply 5):
An interesting idea that was previously mentioned is conducting a test flight, then mid-flight, inducing thermal runaway in one cell of a battery and seeing if it spreads to other cells or outside of the containment box (most likely within a certain amount of time).

They'd never do that in air, they'd do it in an enviornmental simulator.

Quoting AeroWesty (Reply 6):
"The last thing the FAA can stand is to fast-track this and then have something else go wrong," Hamilton said.

That's in essence what I said in the previous thread and got a lot of push-back on it. Actually I said Boeing could not stand such a scenario, but the idea is the same.

Quoting B777LRF (Reply 7):
The whole idea of "let 'er burn, containment will do" as the sole and final fix is utterly perplexing, runs contrary to everything the safety standards of aviation embrace, and should not be allowed to stand.

To be the devil's advocate, and to echo what was said in the last thread, this is how engine blade containment works. The issue we both have is that Boeing is amazingly mute about what they are doing to address the single cell failure issue.

Quoting AngMoh (Reply 9):
Boeing is not improving the thermal management as they admit they don't know what caused the thermal runaway. They only try to make the thermal runaway harmless. And here I think Boeing underestimates the degree that other parties will cover their butt. The FAA, being a government organisation, is not going to take any risks because they received enough criticism till now, and airlines are going to play it safe because they can not afford another smoking 787 in the news.

I think I see FAA manuevering for a climb-down. I don't know to what degree the other players are going to go along.

Quoting AA737-823 (Reply 10):

The FAA exerts testicular fortitude when and where they wish. We've seen them over-punish some, while simultaneously under-punishing others. But it may be a moot point; in the linked article above, it's reported that the JTSB has no interest in permitting the airplanes into their airspace until the root cause is known and exhausted.

Yes, that could be how it plays out. It seems JTSB were the ones who visited the firm that manufactures the cells. Perhaps they are the ones taking the lead on investigating the single cell failures?

Quoting sankaps (Reply 11):
In a nutshell Boeing has two things to fix: Significantly reduce the probability of batteries failing in this manner, and improve the containment when the battery does fail. What they have proposed thus far is for the latter; they still do not have a solution for the former, as no one yet knows what caused the batteries to fail.

We are being told that the root cause for these instances of cell failure might never be known because the evidence has been consumed by fire. I imagine there's a list of suspected root causes and relative probabilities based on the evidence, but it's hard to force an action based on this, IMHO. Still, I'm quite concerned that we aren't being told what is going to be done to address the more probable root causes.

Quoting AndyEastMids (Reply 13):
“...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,” said an FAA statement

To me this suggests that the FAA are not requiring Boeing to stop (or reduce the frequency of) batteries failing, but are only expecting Boeing to improve what happens when a battery does fail.

Yes, this is a big part of why I think I see FAA manuevering for a climb-down. It's hard to reconcile 10,000% safe with that statement, though.



Inspiration, move me brightly!
User currently offlinesankaps From United States of America, joined Jan 2008, 2255 posts, RR: 2
Reply 20, posted (1 year 6 months 1 week 1 day 18 hours ago) and read 23484 times:

Quoting Revelation (Reply 19):
To be the devil's advocate, and to echo what was said in the last thread, this is how engine blade containment works.

Revelation, that is true. However I am sure there are, in parallel, certain agreed to numbers for what acceptable engine blade failure rates are; if it were happening at what is feared to be 20x the expected rate and containment too was not working exactly as hoped, then it is highly likely the said engines would be grounded too.


User currently offlinePugman211 From UK - England, joined Dec 2012, 107 posts, RR: 0
Reply 21, posted (1 year 6 months 1 week 1 day 18 hours ago) and read 23373 times:
Support Airliners.net - become a First Class Member!

Quoting Wisdom (Reply 18):
Even though the batteries didn't provide sufficient power for a completely controlled stop, everybody walked away.
Batteries are the electric back-up system of last resort, on which a pilot should be able to rely even on the worst of days.

That's what batteries are for.

So long as your battery isn't on fire or bricked....


User currently offlinecornutt From United States of America, joined Jan 2013, 338 posts, RR: 1
Reply 22, posted (1 year 6 months 1 week 1 day 17 hours ago) and read 23288 times:

Quoting B777LRF (Reply 7):
The whole idea of "let 'er burn, containment will do" as the sole and final fix is utterly perplexing, runs contrary to everything the safety standards of aviation embrace, and should not be allowed to stand.

But as I pointed out in the last thread, that's precisely how we handle blade failures in engines. It is not required to design an engine such that it is guaranteed to never throw a blade, nor does anyone know how to do so. We design containment into the engines.

Quoting Wisdom (Reply 17):
The battery is there to deal with a major electrical failure, such as one that could be caused by major short-circuiting, electrical arching, such as could be caused by a major lightning strike, maintenance error, FOD, etc.
These are situations wherein there is no power flowing from any generators, to the essential systems for flight, no matter whether the generators are or are not producing any power.

You're making assumptions about the architecture of the electrical system that are probably not true. First of all, if an essential bus is shorted, then it will still be shorted when the battery is placed on it. So that's no help. Second, there have to be at least two busses, or sets of busses, that are separate up to and including physically separated routing through the aircraft. You can't ever have a situation, battery or no battery, where a fire in one electrical tray takes out all of the electrical systems. I'm pretty sure that what you said about the ZA002 incident is not true; if memory serves they were able to start the APU and it provided power for the diversion. I think there are either three or four main busses. The captain and F/O instruments can probably be switched to at least two essential busses, and each essential bus can probably be switched to at least two different main busses. If what I've read is correct, the main battery is hard-tied to a single main bus. Lose that bus, you've lost the battery.

And as has been pointed out, the battery simply does not have enough capacity to power the aircraft in flight for five-and-a-half hours. Likely it does not enter into the ETOPS calculation at all.


User currently offlinea3xx900 From Germany, joined Jan 2004, 335 posts, RR: 0
Reply 23, posted (1 year 6 months 1 week 1 day 17 hours ago) and read 23206 times:

I don't know if this has been asked before and excuse me for not searching 11 topics and hundreds of replies for this, but:

Why can't airlines even reposition their aircraft (non-rev) to their home airports? E.g. the ANA 787 sitting in FRA and the JAL sitting in BOS?



Why is 10 afraid of 7? Because 7 8 9.
User currently offlineStitch From United States of America, joined Jul 2005, 30914 posts, RR: 87
Reply 24, posted (1 year 6 months 1 week 1 day 17 hours ago) and read 23187 times:
Support Airliners.net - become a First Class Member!

Quoting a3xx900 (Reply 23):
Why can't airlines even reposition their aircraft (non-rev) to their home airports?

They can with the proper waivers. Evidently they are content to leave the planes where they are for whatever reason(s).


25 cornutt : They can, if they do the work to plan a ferry flight with the proper restrictions. In fact, I think that one or two of them have been moved. But righ
26 par13del : It should also be mentioned that while on approach most essential systems were coming back online I believe independent of the battery, the experts c
27 RayChuang : My guess is that Boeing should have a "safer" battery ready by late this summer, and eventually the 787 will go away from the current Li-On battery de
28 sweair : Too bad no fuel cell options are in the market, as Airbus told, it filled the cargo hold on their A320.. Isn´t there a market to design and build Jet
29 Rheinbote : That kind of flying refinery would probably be even harder to certify than Lithium-Ion batteries.
30 kanban : So as we go into part 11, everybody from the airlines to the FAA, NSTB to Boeing are posturing through releases (leaked or otherwise) and many posters
31 7BOEING7 : During the 777-300ER certification Boeing did at least one flight with a simulated decompression (flight at 10,000ft) and one engine out for 5 hours
32 Stitch : Been reviewing the PPRune.net threads on this issue and found the following: In regards to JA804A, NHK News is reporting that the JTSB has determined
33 nycdave : Why would they even need to do this in a test flight? If you're testing the containment between cells, and within the unit as a whole, seems like you
34 justloveplanes : Containment properly done make this issue a non-event from a thermal safety perspective. As has been stated previously, the total amount of energy re
35 blrsea : I have a question regarding the new containment and venting design that Boeing has proposed. Will they actually let a battery catch fire and verify th
36 sweair : I they can simulate a nuclear blast they surely can simulate a lithium fire. Germany and later China did test to shut down cooling on the HTR reactor
37 mjoelnir : Here is were Boeing should look at the possibility of subdividing the batteries. Taken two half sized gives the same KW/h at about the same weight bu
38 bellancacf : A quick look around the Web hasn't turned up any information on the kind of batteries that Boeing was proposing having in the SUGAR Volt aircraft, tha
39 sankaps : I think my earlier comment addressing this line of reasoning was lost in the discussion above: I am sure there are, in parallel, certain agreed to nu
40 packsonflight : The FAA will have to settle for less than 100% security, they are supposed to, but I cannot see FAA climb down from the special requirements set for
41 justloveplanes : This would depend on the intent of the special requirement. The assumption for this requirement was a design to provide adequate safety margin for fa
42 Rheinbote : A SUGAR Volt concept is like 30 years away at best. You would have to improve energy density by a factor of 100 over Lithium-Ion battery technology t
43 packsonflight : For starters the assumed failure rate was 1:10,000,000 operating hours. I guess that the regulator wanted firstly: to assure that with Li battery sys
44 AllegiantFlyer : How much money are companies loosing from this grounding?seems to be taking a long period of time.
45 rcair1 : Please do not equate what I say with what Wisdom is saying. With all due respect, we do not agree. I would expect that Wisdom feels the same way. By
46 7BOEING7 : I agree totally. Wisdom is completely distorting the actual use of the Main battery in a modern airliner
47 bellancacf : to Rheinbote @ 43: 100-fold! That IS some speculation, then. I wonder what they had in mind. Presumably something, or the whole thing seems like a pip
48 mjoelnir : So to talk facts. You say there is NO WAY that the ac part of the electrical system goes down and does not come up and the batteries have to keep car
49 DTW2HYD : Boeing is already on record saying they studied every Li-on battery including the ones used in consumer electronics. Tesla has a white paper on their
50 mjoelnir : That I believe That I do not believe. The system is resetting while the batteries are running the flight instruments. Why would you design that syste
51 alfablue : I don't think it's an engineering problem anymore to be honest -- the dimensions of this grounding are huge. It's a huge PR disaster already independ
52 XT6Wagon : no you can't as the shutoff is at a point in time where the battery is no longer able to safely provide power. So if you are using the battery long e
53 alfablue : Sorry I should have been more specific -- I didn't mean a shut off at a low state of charge. I was more thinking of an automatic software shut off du
54 rwessel : That's not exactly true. There's some level of reliability the electrical system has to achieve, I'm assuming it's the one-terminal-failure-in-a-bill
55 mjoelnir : So not to talk around the bush, the failure rate, 2 in 50.000 hours, exhibited by those batteries is low enough regarding the electrical safety part?
56 Revelation : It seems one then have a perfect containment system, or one that's "not remotely likely" to fail, i.e. once in 10e6 flight hours. Should be interesti
57 moo : The FAA cannot say that the two data points mean the plane was unsafe - its entirely possible that Boeing could prove that the the two failures fall
58 sankaps : True, but the failures do raise the question of whether it is a statistical anamoly, or whether there is an underlyin problem. Which is why this rema
59 moo : Yup, I was just highlighting that there was a possible avenue where Boeing could end up doing nothing at all. A highly unlikely course of action, but
60 Wisdom : I love it when a discussion gets technical. Time for some boring technical specs. I'm a EASA specialist; not really FAA, so I'll quote from EASA. The
61 lightsaber : Yea... but the stats were bad for the 787 that week with two fuel leaks, a cracked windshield, and the batteries. The fuel leaks were due to some bad
62 rcair1 : I agree that it is not "just" an engineering problem - and it is debatable which, the engineering or PR problem, is more difficult to address. Engine
63 7BOEING7 : Good--The EASA alternate power source for the 787/777 is the RAT (with the battery as a "backup"), the alternate power source on the 737 is the batte
64 AeroWesty : Perhaps I'm just misreading this, but how do the engines still turn in the fuel exhaustion scenario you described?
65 Kaiarahi : I believe you're misinterpreting the EASA requirements. On RAT aircraft, the RAT is the independent alternative source of power. The RAT is not time
66 7BOEING7 : When a jet engine runs out of fuel the fire goes out but the engine does not stop spinning--as opposed to a propeller driven airplane where you want
67 alfablue : I am posting the relevant regulations below. On an ETOPS/LROPS flight (in addition to what wisdom posted) with an aircraft equipped with a RAT -- "su
68 justloveplanes : It is probably not totally trivial, but definitely a principle in common use, it's just a matter of how heavy Boeing wants to go. As a common referen
69 7BOEING7 : The engine "windmills" due to the airflow through it--faster or slower depending on the speed of the aircraft.[Edited 2013-02-25 08:51:50]
70 Kaiarahi : Read carefully, the requirement describes precisely the 787 system: The second requirement does not apply as loss of all engines does not prevent RAT
71 AeroWesty : Ah, thank you. I understood about the windmilling part, but didn't know that in that state it provided any useful power to any system on the aircraft
72 alfablue : I am not a lawyer but I interpret it differently as this section of the Regulations does not apply to batteries as such but refers to the RAT and its
73 Wisdom : alfablue, regarding ETOPS/LROPS, I found the relevant section: AMC 20-6 rev. 2 Effective: 23/12/2010 Annex II to ED Decision 2010/012/R of 16/12/2010
74 rwessel : No, it quite clearly says you need three, unless failure of all three is not "extremely improbable". The APU can start off engine power if any one of
75 Post contains images lightsaber : Thank you. That implies ETOPS 180+ will have to be revisited. I suspected so, but I didn't have the exact regulation in front of me. Lightsaber
76 XT6Wagon : nope, the failure chance of the primary electrical system is so small, coupled with the failure rate of the APU being also extremely rare means that
77 7BOEING7 : In my understanding the 787 already has ETOPS 180 and ETOPS 180+ has not been granted yet so it doesn't have to be revisited. . Assuming the battery
78 Post contains images rcair1 : I'm not a lawyer either - though somebody accused me of sounding like one the other day. However, I do spend inordinate amounts of time reading a for
79 Kaiarahi : EASA has 22 official languages. The agency's working language is English, but the requirement may have been first drafted internally in another langu
80 packsonflight : What is the meaning with all this?? Are you really saying you can dispatch the 787 with only one battery?? sounds rather funny to me.
81 7BOEING7 : Answer: Yes
82 Wisdom : The issue is not the failure rate of the APU, but the "failure to start the APU rate" if the APU battery is not reliable. It means that the 4th elect
83 Stitch : In normal 787 APU-start operations via battery only, the Ship's and APU battery together start the APU. You can dispatch without the APU battery beca
84 7BOEING7 : That may be possible but I believe if you remove the APU battery the APU is deemed INOP. Anybody got an MEL?
85 Stitch : Why would you deem it INOP? You'd normally start it by using the engine generators in flight or using ground power at the gate. Even in a fuel starva
86 mjoelnir : I thing all of you are tip toeing around the possibility of electrical as opposed to a generating failure. Ok you have generation pretty well covered,
87 XT6Wagon : someone else stated that the APU will auto start when a generator goes offline. So I'm not sure that the pilots attention would even be needed. Its b
88 mjoelnir : We are talking about a new type of battery used the first time in an commercial air plain showing a lower reliability than the types used up to now.
89 Stitch : The engine and APU generators all feed the 230Vac system while the batteries feed the 28Vdc system. So if you lose the 230Vac system (VF AC BUS1 and
90 mjoelnir : You are still nearly talking about generating. Lets say you lose the rectifiers/AC DC converters. 230V are still up 28V DC is down.
91 Wisdom : Remember that a B767 has 2 engines, 1 APU, 1 RAT (flight controls), 1 Hydraulic-driven generator, 1 reliable main battery, 1 reliable APU battery, an
92 kanban : Seems to me that we have (based on hours in use) reliable batteries, with two having had a problem. I have seen no reports of the 787 requiring batte
93 Post contains images rcair1 : Yes - the APU battery is not required by the minimum equipment list. That is why the APU battery and main battery are identical. It was designed that
94 Stitch : If some event took out the Transformer Rectifier Unit and both Remote Power Distribution Units, I would not be surprised if it would affect the 28Vdc
95 7BOEING7 : Yes the APU can be started in many different ways, however, nobody (with credentials) has confirmed whether the APU can be started without the APU ba
96 Post contains links Wisdom : From the MMEL on the FAA website: http://fsims.faa.gov/PICDetail.aspx?...d=99F881A26E3108C186257ABC00525F34 -31-01 APU Battery C 1 0 (M)(O) May be in
97 rcair1 : From the article in Aero_Q407 magazine (Boeing). "The power source for APU starting may be the airplane battery, a ground power source, or an engine-
98 Wisdom : It doesn't matter. The MMEL that I posted at reply96 says, "no APU battery, no ETOPS". An unreliable APU battery (replaced at an estimated average of
99 Post contains links Stitch : That's already been confirmed by tdscanuck and CM. It is done by using one of the engine generators. This is also stated in in an article in the Q4_2
100 tugger : Then I am reading what you posted incorrectly? Your quote noted ETOPS180: What ETOPS is the 787 currently certed for? Tugg
101 7BOEING7 : Excellent, is that a public link? Is there a DDPG there also, the (M) & (O) indicate there are some maintenance and operational procedures that m
102 Stitch : ETOPS-180 per the FAA and EASA TCDS. FAA: EASA:
103 tugger : Thanks, that's what I thought. So according to Wisdom's quote, the 787 is OK to fly without the APU battery (provided the VFSG systems operate normal
104 Stitch : Well that it says "or" implies, at least to me, that the battery need not be installed to start the APU from either an engine generator or ground pow
105 Post contains links alfablue : This guy really grows on me -- Airbus is apparently looking into another assembly line for its 350 -- the discret period is over and Leahy makes it v
106 Stitch : It's easy for JL to speak when the first production A350 is just starting to come together and they have the time to make the switch. One wonders what
107 alfablue : You meant on the ground -- after all we talk about a grounding. Problems for the 350 might still arise so I find his statement quite bold as well but
108 7BOEING7 : Until we have the (M) & (O) procedures from the DDPG (or equivalent) we won't know for sure whether you are allowed to start the APU without the b
109 cornutt : You seem to want to postulate incredible combinations of circumstances that only occur in bad novels. I think there are at least four sets of rectifi
110 Post contains images rcair1 : Give me a break - you think Airbus would be changing and Leahy crowing if the 787 had not had issues? No - they'd be moving ahead with Li-Ion batteri
111 Post contains links trex8 : Guess ANA also agree http://www.flightglobal.com/news/art...s-787-suspension-to-31-may-382683/
112 sankaps : Not sure I understand the point of your comment. If the problem was with the A350, I'm sure his reaction would be just the same, except it would be d
113 mjoelnir : Why go so far? If you loose the rectifiers you loose the 28V DC.
114 Post contains links alfablue : You misunderstood my comment - I was trying to express the oposite in a way - Leahy used in a few sentences following keywords: safety, incidents, ri
115 mjoelnir : Most of the things thought about for preventing accidents are very unlikely. A rectifier going down is not unusual, several is unlikely. That is why
116 Wisdom : You gotta love Airliners.net Since 9 threads the debate is on whether a stronger containment is sufficient for ETOPS 330. Now suddenly, after some off
117 rwessel : This is getting silly. You need to main battery to power the electrical system during the recoveries from certain failures. Without knowing the vario
118 Post contains links hivue : See the Boeing video with Mike Sinnet posted in part 10 -- http://video.boeing.com/services/pla...0eUADvmgWcuM2F&bctid=2167891130001 Some posters
119 7BOEING7 : Thank you very much for providing an answer to the never ending question. I probably should have listened to Mike's presentation all the way through
120 Post contains images rcair1 : Yep - I sure did. Interesting how comments in a forum can be taken so differently than intended. I might say - maybe Boeing will be lucky next time -
121 frmrCapCadet : A little off topic, but I don't think it has been specifically mentioned. Airline manufacturers and regulatory agencies are unique (or bad grammar ver
122 hivue : You could very well be correct. However, his statement in the video that if the APU battery goes belly up in flight and the APU is running the APU sh
123 7BOEING7 : We do have the MEL. It's above in Reply 96 from WISDOM who also provided us with the FAA website which gets you to to all the MELS. Unfortunately we
124 Post contains links tarmacphotos : I just saw this on Flightaware http://flightaware.com/live/flight/U...2/history/20130226/1915Z/KLAX/RJAA Is this a glitch or are they flying?
125 Stitch : Glitch. It's operated with a 777-200ER.[Edited 2013-02-26 12:30:50]
126 rotating14 : Hello all, So I arrived home for from work and caught the tail end of the CNBC show Fast Money, which highlighted Boeing for a bit but what caught my
127 Post contains links Stitch : Cowen & Co. analyst Cai von Rumohr posted a research note today stating he thought the FAA might respond to Boeing's proposed fix next week, but
128 Post contains links rotating14 : Update --> So it's not allowing them but giving Boeing the yay or nay for the proposed fix. http://www.suntimes.com/business/184...er-solution-next
129 PHX787 : So this pretty much implies that the FAA is going to review the proposed fix, give them the yay/nay on doing the fix, and subsequently allowing them
130 ServantLeader : And science is inexact and IMO it is the "PR stuff" that will decide if and when the 787 goes back into revenue service. The hard engineering / scien
131 Wisdom : This is my view as well. Better containment should provide sufficient safeguard for normal operations without ETOPS, under certain conditions: -The c
132 kanban : maybe a slight over kill.. one the passenger next to you may smell worse than these fumes BTW 10 flights in the last 8 days had smoke or odors ... an
133 7BOEING7 : I agree. If the FAA signs off on the present Boeing fix I think ETOPS 180 will not be greatly affected. Possibly adding a working APU as an initial r
134 Post contains links and images NAV20 : Isn't 'von Rumohr' a marvellous name for an analyst? Hopefully we are approaching a 'turning-point.' So far, though, Boeing are still at the laborator
135 Post contains images hivue : Might be a good one for some a.net posters too.
136 Wisdom : I'm a rational guy. I've seen airplanes wide open and have seen things only a few other guys in this world have seen. Do I have an issue with the B78
137 hivue : The implication here is that bleed air will not fail independently of engine failure. I am not involved in aviation but I suspect this is not the cas
138 kanban : Well Wisdom, I spent 35 years in the industry and have seen many dramatic changes and saw and understood many more things in the last 50 years than I
139 mjoelnir : 3 out of 100 batteries, 50 frames times 2 batteries each. In the ANA bird the second battery was bulging, that is 2 batteries in one air plane. And B
140 Sassiciai : 11 threads already, and the speculation is the same now as in post 2 of the first thread! I cant contribute to all this speculative stuff about batter
141 hivue : IIRC from previous posts in this thread, it's likely that few/none of the swapped out batteries went in the trash. Mx checked them, fixed ones that n
142 Stitch : They're canceling services, reducing frequencies, subbing other equipment, extending existing leases and other options. The next batch of new custome
143 sankaps : Not just chose the battery, but selected the underlying technology, specified the specs, and pretty much self-certified them. Only thing they did not
144 Sassiciai : The existing customers are facing what one could call "tactical"" problems - they have timetables, bookings, and even, in some cases, "787-glory" prog
145 ServantLeader : In a word, not very well thank you very much. This thread gets deep into the physics and chemistry of the Li-ion battery system and its function aboa
146 jumpjets : Not to mention Thompson Airlines/TUI in the UK who have been heavily promoting their new super 787 services from this May and BA who presumably, befo
147 Sassiciai : Thanks! it's exactly that I'm a bit distressed at 11 threads about batteries and chemistry, with little discussion on the obvious impact on airline o
148 ZKCIF : This concerns those who expect to get something from the first 100 from these 750. for others, the dates are not specified so precisely. Manufacturin
149 mjoelnir : Completely discharged was one of several reasons, the other (s) not defined. So how many were bad and not just discharged. 1, 2, 10, 20? And for what
150 hivue : 50 in customer hands (or, rather, sitting on their ramps), yes, but not 750+ "in progress" -- most of those are just line items in purchase contracts
151 rcair1 : Huh? Are there things in physics and science we don't understand? Yes. Are there tradeoffs between 'perfect' science and estimates? Yes? But I'm not
152 Post contains links Aesma : I thought the Tech/Ops thread would be discussing these issues but apparently it's similar to this one : Tech/Ops Discussion Of The 787 Grounding (by
153 hivue : I agree. That would be very interesting to know. And if several actually were bad very early in their expected lifetimes rather than just in need of
154 Post contains links Wisdom : Yes it's Boeing's fault. ICAO said it in clear words: ICAO Decision Temporarily Restricts Carriage of Lithium Ion Aircraft Batteries as Cargo on Pass
155 AeroWesty : . What is it that you want to do? Keep a running list of flights that have been either cancelled or are on hold due to the groundings? That might be a
156 Post contains links alfablue : Does not look too good if the battery manufacturer does not agree with Boeing.
157 Post contains links spacecadet : I think he just wants some actual new information about how this is actually affecting airlines and schedules, rather than speculation on battery che
158 Post contains links AeroWesty : I see where you're heading, and I can only say that there's nothing preventing anyone from posting that info at any point in time. This is the thread
159 RickNRoll : I think people talk about topics that are raised. If you don't raise it, it may never be discussed.
160 Stitch : There are reports of plans to improve the charge monitoring system for the batteries.
161 Post contains images flood : For F's sake... where did my post go Yuasa wants a voltage regulator in front of the battery. I don't see a charge monitoring system protecting agains
162 Post contains images rcair1 : No it isn't. At most - the Boeing issue is just the thing that triggered the _temporary_ restriction. The issue of shipping Li-Ion batteries on non-c
163 Post contains links blrsea : Seattle times reporting that FAA chief said extensive testing will be required before 787s are allowed to fly. Says April/may timeframe may not be rea
164 spacecadet : As is the extremely similar one in tech/ops. Thanks for the info, but it wouldn't have otherwise occurred to me to have read a thread about a Seattle
165 AeroWesty : I didn't say that's where you should have looked, I pointed out the info that I did post elsewhere as an example, and could have been posted here if
166 Post contains links B777LRF : ANA, JAL extends grounding through May 31st: http://www.flightglobal.com/news/art...-787-suspension-to-end-may-382860/ Seems like the airlines closest
167 NAV20 : I think the key proposed changes are increased separation/insulation between battery cells, increased cooling/ventilation, extra sensors to give earl
168 packsonflight : I guess Boeing is working on final solution by now that involves new / revised design of the battery system that involves some level of recertificati
169 mjoelnir : The second battery, apu, on the ANA frame showed "bulging". If they find two different causes, than it will not be the battery but the electrical, el
170 Post contains links scbriml : If by this you mean what Boeing proposed to the FAA last Friday is an interim solution, then you're mistaken. Several news stories said that Boeing h
171 ServantLeader : Boeing has bungled the 787 program in more ways than can be recounted -- their handling of the battery crisis is textbook wrongheaded -- instead of g
172 hivue : The impression I get is that the 787 is married to Li-Ion (though not necessarily to the current specific chemistry) due to power requirements. As pa
173 Aesma : Well the 787 grounding has many consequences, but knowing that this flight is canceled and that flight is operating with another plane isn't really r
174 Stitch : It's not just power requirements, but also recharging requirements - Li-Ion recharges at a quicker rate than NiCad. One of the scenarios Boeing had t
175 Post contains links mjoelnir : Lets not go overboard. http://www.s399157097.onlinehome.us/SpecSheets/LVP10-65.pdf 8 of the bigger cells in the above specsheet. We are talking about
176 7BOEING7 : The sky is falling! The sky is falling! True the Ship's battery is needed for the brakes on landing, however, after deployment the RAT powers the ess
177 hivue : That's a very good question. My point in post 174 -- based on no expertise but just what I have heard and read -- is that in the absence of significa
178 Post contains links alfablue : It's an interesting article about ANA, its pilots and the 787 by Reuters (NO BATTERIE TALK) http://www.reuters.com/article/2013/...liner-pilots-idUSL
179 Post contains images Stitch : Sorry - bad editing of my original post on my part. I'd originally hypothesized the RAT also failed, so the Ship's Battery was the only source of pow
180 hivue : As I understand it, that is precisely the approach the certificating authorities are supposed to take.
181 ADent : If this is true then they really need to fire the 787 management team. They need to be working on a NiCd solution (or at least some other solution th
182 mjoelnir : That is the no can do philosophy on this page. What can the reasons be: 1. You have to change the battery chargers. 2. The voltage line of the batter
183 sweair : Just beacause Airbus going NiCad doesn´t make it a good option, try being less partial please. There ARE very safe Li batteries out there, but they h
184 PHX787 : Buddy of mine who is training in Japan to fly the 787 was told his training was put on hold until June. Not a good sign at all.
185 Post contains links ServantLeader : The problem is at the very top -- Jim McNerney, in his dual role as CEO and COB, has thrown several 787 managers under the bus over the past 5 years
186 ServantLeader : Why do you find it necessary to apologize for Boeing? Airbus made a wise and rationale decision to abandon Li-ion batteries -- Boeing insists on play
187 7BOEING7 : Fortunately that happens much more often than your senario. In your own mind. Based on the present price of Boeing stock most investors are more than
188 hivue : Well, if NiCad is in fact a viable option and Boeing aren't right now working on it double overtime -- and I haven't read or heard any rumor, specula
189 planesmart : The finance industry prefers to fund safe aircraft, rather than better aircraft when the technology is eventually 'right'. Probably passengers and ai
190 Post contains images sweair : I don't defend Boeing, I defend technological progression and in my eyes the 787 is the most progressive airliner project in many many years. I like w
191 moo : Airbus did a little more than make a knee jerk reaction - this isn't just about bad press, it's about how Boeings issues change the playing field for
192 sweair : I don't think they will have a smooth EIS but I guess you do. As conservative as it is it´s still a new aircraft, new materials, new suppliers etc.
193 ServantLeader : You have no idea what I think about the A350's path to service and that's a moot point anyway. We all benefit from technological advances irrespectiv
194 mjoelnir : It is strange this Airbus fans, enemy's, anti Boeing. Somebody criticising, the battery is anti Boeing. Somebody saying the containment does not work
195 Stitch : Lithium-Ion is hardly an unproven technology, even if it had seen only limited use in commercial aerospace applications before the 787. As conservati
196 kanban : OK I'm a retired Boeing guy.. and the pains and tribulations they've gone through trouble me, however when outsiders with NO process knowledge start
197 bradmovie : Here's something I had not read before, quoting Reuters who took it from the Wall St. Journal: (http://www.reuters.com/article/2013/02/27/us-boeing-78
198 mjoelnir : The Cessna incident with the CJ4 Citation burning out on the ground because of a battery fire should, even if is was only a business jet, have got so
199 rcair1 : Because most of the Boeing fans, and many of the 'neutrals' have given up and left this thread. Really? Lest see here.... "Airbus made a wise and rat
200 Stitch : That the FAA moved to so quickly ground the 787 fleet is, in my opinion, proof that it did get them to think. And it probably had Boeing thinking, as
201 par13del : So a question, if the FAA rejects Boeing's current proposal, do you expect Boeing to throw their hands up and cancel the 787 program, refund the mill
202 mjoelnir : There is absolutely no question about Boeing cancelling the program and no question that the B 787 will fly again. The question is not if but when. I
203 RickNRoll : I have absolutely no idea. Airbus just happened to be able to learn from Boeings mistakes in this case. It hardly makes them a better company or airp
204 Wisdom : This is exactly what I've been saying since day one. If you look at the proven battery technology used, the cause is more likely to be coming from ou
205 art : There is no evidence that the 787 has basic design flaws that compromise safety (eg Comet, DC10). It uses batteries that have failed at an unacceptabl
206 BoeingVista : I think that Boeing have been really lucky that the 787 battery meltdowns happened on the ground or within 15 minutes of an airfield. I think that Ai
207 ServantLeader : Sorry, but that makes absolutely no sense. Boeing produces the airplane and the batteries are part of it, and you say that Boeing is not at fault whe
208 Wisdom : This message is doing the rounds of the net. Can't post any source, can't verify what's in it, could be plain fear mongering, so take it with some di
209 sonomaflyer : So the question to me is, have we not ruled out unexpected/planned for spikes from the panels etc? We know UA had panel issues and there were allegati
210 7BOEING7 : The one thing he is most happy about (pension fund being fully funded) is just another of the myriad of facts that he has totally wrong. McD took ove
211 Post contains images hivue : The "whatever reason" is likely that they needed that power. They do quality aircraft work in lots of places around the world besides at B and AB --
212 sonomaflyer : They have a frame that's static fatigue testing IIRC. I would expect they would cycle that frame over and over again and see how it does.
213 Post contains images rcair1 : From a EE standpoint. (Yes - I'm a Fire Fighter, but my 'job' is a EE - BS, MS, Ph.D.) none of these are overlly compelling - basically you are throw
214 rheinwaldner : I don't know because one need to be partial in the other direction to feel that way (as you have confirmed). Before your post Airbus hardly ever was
215 seahawk : I think only flying the planes will help to find the cause.
216 BoeingVista : Agreed but the planes would have to be full of PAX as they may be part of what is causing the problem. A lot of systems work perfectly well in testin
Top Of Page
Forum Index

This topic is archived and can not be replied to any more.

Printer friendly format

Similar topics:More similar topics...
FAA Grounds 787, Part 8 posted Tue Feb 5 2013 04:23:12 by 777ER
FAA Grounds 787 Part 6 posted Sat Jan 26 2013 20:01:59 by NZ1
FAA Grounds 787 Part 5 posted Wed Jan 23 2013 12:05:50 by iowaman
FAA Grounds 787 Part 4 posted Mon Jan 21 2013 14:34:20 by iowaman
FAA Grounds 787 Part 3 posted Sat Jan 19 2013 02:14:57 by NZ1
FAA Grounds 787 Part 2 posted Thu Jan 17 2013 09:49:30 by iowaman
FAA Grounds 787, Thread 9 posted Sat Feb 9 2013 21:44:13 by 777ER
FAA Grounds B787 Part 7 posted Wed Jan 30 2013 14:31:29 by 777ER
FAA Grounds 787 posted Wed Jan 16 2013 15:07:34 by brons2
787 Production/Delivery Thread Part 11 posted Sun Nov 4 2012 18:07:21 by NZ1