Problems with the Dreamliner battery

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In summary: Basically, it's a new design that allows the aircraft to operate with a smaller number of batteries and keep the batteries in a more stable and safer condition. As a result of this design, there have been some concerns raised about the possibility of an interaction between the battery and the electric power distribution system. However, so far no such interactions have been reported.
  • #141
jim hardy said:
I think it's too early to call them "Firebirds"
but it bears watching.

Oops, there goes another one (despite the failed attempts to keep it out of the news).

http://uk.reuters.com/article/2013/07/31/uk-boeing-dreamliner-qatar-idUKBRE96U0GB20130731
http://blogs.crikey.com.au/planetalking/2013/07/27/attempt-to-hush-up-new-qatar-787-fire-fails/

Looks like that was a replay of the problem that caused a fire on a flight test a/c back in 2010.
 
Engineering news on Phys.org
  • #142
This is a great line from that link:

http://seattletimes.com/html/businesstechnology/2021481675_boeingexecutivesxml.html#.UfLuEn0o6c8.twitter
As chief project engineer on the Boeing 787 Dreamliner program, Mike Sinnett slept with his BlackBerry set to wake him whenever a 787 Dreamliner in service anywhere in the world had any significant problem.
...
Sinnett now steps sideways to a less stressful position as vice president of product development. That means he’s in charge of developing concepts for future airplanes, beyond the current pipeline of new jets.
 
  • #143
...he’s in charge of developing concepts for future airplanes,

I guess that's execuspeak for '...you're free to think about anything you want, but don't go around the machinery...'poor guy.
 
  • #144
Well, the 787 design was a nice concept for a future airplane once upon a time. (And quite sensible compared with some of the stuff that "future concepts" departments dream up!)

The problems only started when somebody decided to build them :smile:
 
  • #145
AlephZero said:
Well, the 787 design was a nice concept for a future airplane once upon a time. (And quite sensible compared with some of the stuff that "future concepts" departments dream up!)

The problems only started when somebody decided to build them :smile:

It should be a good plane once they get the electrics squared away.

I think we're seeing a general excess of automation these days - it's the "Tower of Babel" myth, aka "Law of Diminishing Returns" . Newer and Better are not synonyms.

:tongue:
 
  • #146
jim hardy said:
It should be a good plane once they get the electrics squared away.

:tongue:

The things that Boeing builds in-house are fantastic but the complete outsourcing of the electrical system in the 787 so far looks to be a big mistake for something that complex and new.

http://www.post-gazette.com/stories/business/news/electronics-outsourcing-weakened-boeings-control-over-787-systems-694464/

On jets before the 787, Boeing Commercial Electronics or BCE integrated components from many different suppliers so they worked together properly. And if suppliers got in trouble, BCE stepped in and got the job done.

"Now they don't have that capability," said Jerry Packard, another former BCE manager. "That's all lost."

In contrast to Boeing's well-known move to let "global partners" design and manufacture the 787's wings, tail and fuselage, the way it handed design control to 787 systems partners, including management of subcontractors, received little attention at the time.

After this year's costly three-month grounding of the plane from January's battery problems, that approach is getting new scrutiny.

Longtime industry analyst Richard Aboulafia worries it may bring the 787 more grief in future.

"Without complete oversight of the subsystems, they might be finding systems glitches for years," Mr. Aboulafia said.
...
The 787 is the first Boeing jet with all its electronic components sourced from outside suppliers.
 
  • #147
The 787 is the first Boeing jet with all its electronic components sourced from outside suppliers.



Machiavelli gave good modern management advice in "The Prince", ca 1513:

I conclude, therefore, that no principality is secure without having its own forces; on the contrary, it is entirely dependent on good fortune, not having the valour which in adversity would defend it. And it has always been the opinion and judgment of wise men that nothing can be so uncertain or unstable as fame or power not founded on its own strength. And one's own forces are those which are composed either of subjects, citizens, or dependants; all others are mercenaries or auxiliaries. And the way to take ready one's own forces will be easily found if the rules suggested by me shall be reflected upon, and if one will consider how Philip, the father of Alexander the Great, and many republics and princes have armed and organized themselves, to which rules I entirely commit myself.
http://www.constitution.org/mac/prince13.htm
When you export your expertise you export your strength and security.


Rickover echoed it : "Where nobody is responsible, everybody is irresponsible."
Today's 'Blame the Vendor' game is pure irresponsibility.
See also San Onofre Steam Generators thread.

old jim
 
  • #148
Ptero said:
...
http://updates.jalopnik.com/post/34669789863/more-than-a-dozen-fisker-karma-hybrids-caught-fire-and [Broken]
...
10/30/2012 --^

old update --v

Fisker Reveals Cause of Karma Fires During Hurricane Sandy
Published: 11/06/2012
...
There were no explosions as had been inaccurately reported. The Karma's lithium-ion batteries were ruled out as a cause or contributing factor.
...
Fisker engineers determined that the damage to the Karmas was the result of the cars being submerged under 5-8 feet of seawater for several hours that left corrosive salt in a low-voltage Vehicle Control Unit in one Karma.

The Vehicle Control Unit is a standard component found in many types of vehicles and is powered by a typical 12V car battery. This residual salt damage caused a short circuit, which led to a fire that heavy winds then spread to other Karmas parked nearby.

Bolding mine.

I seem to remember, from my days in the submarine fleet, that you should never let salt water come in contact with the lead acid battery.

And given that the Karma is a gas/electric hybrid, I can only imagine that the gasoline may have been a contributing factor to the spread of the fire to other, non-Karma vehicles.

I have a date with the coast in a couple of weeks. Perhaps I should take my somewhat used marine deep cycle battery, and throw it into the ocean, tethered to my 6 gallon outboard motor fuel tank, and see what happens.

But then again, maybe not.
 
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  • #149
Ah ha!

Just did the experiment.

Do not try this at home. Although I didn't die, you will...

In trying to understand how such a thing could happen, I tried to figure out the resistance of seawater, as the google answers to my question, used bizarre, unheard of terms:

The average conductivity of sea water at 20degC and a salinity of 35g/kg is:
4.788 S/m (Siemens/meter)

Anyways, I mixed together a solution of seawater(1 pint of water and 1 tblsp of salt in a pyrex measuring cup), and tried to measure the resistance with my VOM: 1.2kΩ on the 200kΩ scale, and 85kΩ on the 2MΩ scale. Complete nonsense.

So I hooked up my marine battery in series with a 1Ω resistor with my 1 pint of seawater and came up with a value of ≈11Ω.

pf.2013.08.11.1144am..om.nacl.h2o.pb.battery.experiment.jpg

I decided that the 11Ω value was irrelevant to the problem, as while I watched, Hydrogen and Oxygen gasses were being emitted at a non-insignificant rate. I didn't dilly-dally in deciding that this experiment could have very bad results, as my 6 gallon gasoline tank was tethered to my battery, and less than a foot away. A spark would have resulted in the HHO mixture igniting, potentially igniting any fumes from the gasoline tank.

I disconnected the experiment, in a thoughtful manner, as, an acquaintance of mine, while trying to retrieve his wallet from the dashboard of his burning car, was unfortunate enough to do that, the moment his car burst into flames.

He never looked the same after that. He looked a little better after the plastic surgeons made him a new nose, but not much.
 
  • #150
jim hardy said:
...

Rickover echoed it : "Where nobody is responsible, everybody is irresponsible."

...

I quoted someone, to that effect, the other day.

I cannot find my quote, nor who else echoed that...


:cry:
 
  • #151
OmCheeto said:
I quoted someone, to that effect, the other day.

I cannot find my quote, nor who else echoed that...


:cry:

I looked back a bit in your posting history and couldn't find it yet. Do you know which day you did it on?
 
  • #152
OmCheeto said:
Ah ha!

Just did the experiment.

Do not try this at home. Although I didn't die, you will...

In trying to understand how such a thing could happen, I tried to figure out the resistance of seawater, as the google answers to my question, used bizarre, unheard of terms:



Anyways, I mixed together a solution of seawater(1 pint of water and 1 tblsp of salt in a pyrex measuring cup), and tried to measure the resistance with my VOM: 1.2kΩ on the 200kΩ scale, and 85kΩ on the 2MΩ scale. Complete nonsense.

So I hooked up my marine battery in series with a 1Ω resistor with my 1 pint of seawater and came up with a value of ≈11Ω.

pf.2013.08.11.1144am..om.nacl.h2o.pb.battery.experiment.jpg

I decided that the 11Ω value was irrelevant to the problem, as while I watched, Hydrogen and Oxygen gasses were being emitted at a non-insignificant rate. I didn't dilly-dally in deciding that this experiment could have very bad results, as my 6 gallon gasoline tank was tethered to my battery, and less than a foot away. A spark would have resulted in the HHO mixture igniting, potentially igniting any fumes from the gasoline tank.

I disconnected the experiment, in a thoughtful manner, as, an acquaintance of mine, while trying to retrieve his wallet from the dashboard of his burning car, was unfortunate enough to do that, the moment his car burst into flames.

He never looked the same after that. He looked a little better after the plastic surgeons made him a new nose, but not much.

We're going to need to change your username to Danger. Oh wait...
 
  • #153
OmCheeto said:
Ah ha!

Just did the experiment.

Do not try this at home. Although I didn't die, you will...

In trying to understand how such a thing could happen, I tried to figure out the resistance of seawater, as the google answers to my question, used bizarre, unheard of terms:



Anyways, I mixed together a solution of seawater(1 pint of water and 1 tblsp of salt in a pyrex measuring cup), and tried to measure the resistance with my VOM: 1.2kΩ on the 200kΩ scale, and 85kΩ on the 2MΩ scale. Complete nonsense.

So I hooked up my marine battery in series with a 1Ω resistor with my 1 pint of seawater and came up with a value of ≈11Ω.

pf.2013.08.11.1144am..om.nacl.h2o.pb.battery.experiment.jpg

I decided that the 11Ω value was irrelevant to the problem, as while I watched, Hydrogen and Oxygen gasses were being emitted at a non-insignificant rate. I didn't dilly-dally in deciding that this experiment could have very bad results, as my 6 gallon gasoline tank was tethered to my battery, and less than a foot away. A spark would have resulted in the HHO mixture igniting, potentially igniting any fumes from the gasoline tank.

I disconnected the experiment, in a thoughtful manner, as, an acquaintance of mine, while trying to retrieve his wallet from the dashboard of his burning car, was unfortunate enough to do that, the moment his car burst into flames.

He never looked the same after that. He looked a little better after the plastic surgeons made him a new nose, but not much.

Glad you made it back safely!

You are right, 12V + seawater will not burn due directly to the electrical load of the seawater.
What happens is that corrosion (take a look at your contacts that were in the water) can cause low resistance shorts which then can then burn. Their creepage distance requirements probably did not anticipate being submerged.
 
  • #154
the_emi_guy said:
Glad you made it back safely!

You are right, 12V + seawater will not burn due directly to the electrical load of the seawater.
What happens is that corrosion (take a look at your contacts that were in the water) can cause low resistance shorts which then can then burn. Their creepage distance requirements probably did not anticipate being submerged.

If it had been any other car, I probably would not have researched this incident. But I knew Fisker used A123's batteries, and they were one of the safest lithium batteries on the market.

GM turns to A123 Systems for batteries less volatile than Chevrolet Volt’s
December 08, 2011
...
GM is using phosphate-based lithium-ion batteries from Waltham, Massachusetts-based A123 Systems Inc. that are less likely to burn than other lithium chemistry, including that used in the Volt model that went on sale last year, according to the companies. ...

It should be noted that I still haven't sold my A123Q, aka B456, stocks. I foolishly assumed that trading of the stocks would cease once the company went bankrupt. Unfortunately, I was so disgusted with the whole incident, I paid no attention to my portfolio, which was set to auto-purchase shares each month, and only discovered later that I had doubled the number of shares I owned in just a few months. If I hadn't shut that down, it would have doubled again by now. :grumpy:

Oh dear... I see I now own another Q suffixed stock! XIDEQ... :cry:

I guess the battery market is as brutal as the solar panel market.

ps. The battery that I did my seawater test with is an Exide.
 
  • #155
Another dreamliner electrical screw-up. Engine fire extinguishers wired the wrong way round on three aircraft in service.

http://www.bloomberg.com/news/2013-...-in-dreamliners-as-jal-plane-scraps-trip.html

That wouldn't be funny if there was a problem that caused an engine fire. The engine fire extinguishers will put out most things, but they are pretty much a one-off last resort. Discharge a fire bottle into the one engine still working, and you had better be qualified as a glider pilot.
 
  • #156
OmCheeto said:
Oh dear... I see I now own another Q suffixed stock! XIDEQ... :cry:

don't feel bad I still have Enron.
 
  • #157
http://newscenter.lbl.gov/wp-content/uploads/Balsara-dendrite-growth.jpg [Broken]
Here we go again. Dendrites grow slowly over time like fractures.

Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have discovered that during the early stages of development, the bulk of dendrite material lies below the surface of the lithium electrode, underneath the electrode/electrolyte interface. Using X-ray microtomography at Berkeley Lab’s Advanced Light Source (ALS), a team led by Nitash Balsara, a faculty scientist with Berkeley Lab’s Materials Sciences Division, observed the seeds of dendrites forming in lithium anodes and growing out into a polymer electrolyte during cycling. It was not until the advanced stages of development that the bulk of dendrite material was in the electrolyte.
http://newscenter.lbl.gov/science-shorts/2013/12/17/roots-of-the-lithium-battery/

Dreamliner Grounded As White Smoke Spotted -- TODAY!
http://news.sky.com/story/1195209/dreamliner-grounded-as-white-smoke-spotted
 
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  • #158
Another Telsa crash and fire but this one has a 'twist'.

http://ktla.com/2014/07/04/tesla-cr...lits-in-half-in-weho-multiple-people-injured/

labreacrash.jpg


You can see flaming parts of the broken battery pack ejecting flaming cells like missiles but the car looks to be incredibly safe if you are free of the resulting fire.

The first part gives a good view of the scale of the wreck. It looks like the driver was trying to turn or slid at high speed after hitting the Honda and hit the pole near the middle of the car spilling most of the battery in the street. Losing that heavy battery might have saved his life.
https://www.youtube.com/watch?v=kE_u731EmYA
 
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  • #159
nsaspook said:
...
Losing that heavy battery might have saved his life.
...

Not driving any stolen car at 100 mph down the streets of LA, and not self T-boning a light pole, will probably also save your life. (I read that he actually took out two light poles.)

Latest reports say the the thief is still alive, though one of the people he injured is still in critical condition.

I consider this a non-issue.
 
  • #160
If the battery falls out of the car in a side-on collision, I think that's a major design issue in its own right, independent of any pyrotechnic side effects.
 
  • #161
AlephZero said:
If the battery falls out of the car in a side-on collision, I think that's a major design issue in its own right, independent of any pyrotechnic side effects.

The car hit the pole with enough force to slice the car in two. Looking at the layout of the battery, and knowing there are over 7000 individual cells that make up the battery, I'm guessing the "battery" did not fall out of the car.

The gas tank on my truck is about 5 feet long and is positioned centrally, running parallel to the drive shaft. Would that also be considered a major design issue if 17 gallons of gasoline were released in a similar accident? Both the Tesla and my Truck have 5 star crash ratings.

On the following website, they claim:

Pole Side Impact
...
In the test, the car tested is propelled sideways at 29kph (18mph) into a rigid pole.
...

I can go faster than that on a bicycle.

How much would it add to the cost of vehicles if the speed of the test was increased to 100kph (62mph)? Do we really need to engineer vehicles to keep people alive, based on the driving habits of contenders for the Darwin Award?

Consensus at the Oregon Electric Vehicle Assn about this incident? : Yawn
 
  • #162
OmCheeto said:
The car hit the pole with enough force to slice the car in two.

OK, if you think that was the root cause, then that's still a major design issue.

Crash test regulations may or may not be a marketing exercise, but if the car hit a standard item of highway engineering (I'm not familiar with what the US term "pole" signifies here) while being propelled by its own engine, that event is going to happen sooner or later.

I'll be interested to see the first head-on crash between two Teslas with a closing speed of around 200 mph...
 
  • #163
OmCheeto said:
Consensus at the Oregon Electric Vehicle Assn about this incident? : Yawn

They're mainly right. A ICE car could have turned into spinning firebomb also in those conditions. My main point with the post was to demonstrate the reaction of some types of lithium batteries is very similar to carbon based fuels in these extreme conditions with the added punch of not being able to use normal extinguishers like water or water based products to control the fires. The firefighters just letting it burnout was the safest approach. With an isolate car in the street that's a good option if no one is trapped inside, in a flying plane filled with people it's not.

Don't do this
https://www.youtube.com/watch?v=ojGaAGDVsCc

(We have class D bottles at work for hydride metal fires, nasty stuff but we don't have to use the Lithium approved types)
http://www.safetyemporium.com/ILPI_Site/WebPagesUS/detail.htm&&2eiBpe0obDuox2NvxMpoLGxolobo2bbBeJ1gctPw1JaImsaa2r1GcDQUR4Vh_S6alkWaTWuala?09584
 
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  • #164
OmCheeto said:
How much would it add to the cost of vehicles if the speed of the test was increased to 100kph (62mph)? Do we really need to engineer vehicles to keep people alive, based on the driving habits of contenders for the Darwin Award?

First, decide what crash tests are supposed to be testing for.

For example, the US crash tests for fenders/bumpers are impacts with a rigid barrier at 3mph and 6mph, designed to measure the damage to the car.

The corresponding EU test is impact with a deformable object at 25mph, designed to measure the damage to the object - e.g. a pedestrian.
 
  • #165
AlephZero said:
... (I'm not familiar with what the US term "pole" signifies here) ...
Odd, as I quoted a european website, regarding the "pole" test.

About us
Established in 1997, Euro NCAP is composed of seven European Governments as well as motoring and consumer organisations in every European country. (Read more on our members)

I'll be interested to see the first head-on crash between two Teslas with a closing speed of around 200 mph...

That would be fun to watch. Darwinians are quite entertaining, regardless of their energy source.
 
  • #168
Just when you thought it was over... To keep a Boeing Dreamliner flying, reboot once every 248 days. What the heck did they do - give it a Windows operating system? :eek:
According to the FAA, there's a software bug in the 787 Dreamliner that can cause its electrical system to fail and, as a result, lead to "loss of control" of the plane. But why? The FAA says this is triggered by the aircraft's electrical generators, which could give out if they have been powered on continuously for over eight months.
 
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  • #169
Borg said:
Just when you thought it was over... To keep a Boeing Dreamliner flying, reboot once every 248 days. What the heck did they do - give it a Windows operating system? :eek:

Stole this from a comment elsewhere but sounds most plausible:

"248 days == 2^31 100ths of a second. even in 2015, our airplanes have integer overflow bugs "
 
  • #170
One of my solid state drives had nearly exactly the same problem. After a certain number of run hours -- something like 248 days -- it turned-into a a brick. Fortunately, it had a reset routine and bios flash to fix it.

Now with the dreamliner it says "continuously powered", so I suppose you could just reboot it once every 8 months to work-around this bug.
 
  • #171
russ_watters said:
One of my solid state drives had nearly exactly the same problem. After a certain number of run hours -- something like 248 days -- it turned-into a a brick. Fortunately, it had a reset routine and bios flash to fix it.

Now with the dreamliner it says "continuously powered", so I suppose you could just reboot it once every 8 months to work-around this bug.

Have none of the programmers heard of signed integer overflow bugs? At 100hz 248.5 days would be just about right. One woodpecker!
 
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  • #172
Re: Newest Dreamliner Bug.

Once again, this proves that all the kings horses and all the kings men can never make flawless yet complex software. There is no such thing and there never will be.

I'm afraid that the airline industry will be doomed to follow the nuclear industry. During Y2K remediation reviews, we found software written in the early 1960s still in use, and still being replicated from the oldest plants into the newest ones. The source code, who wrote it, what its function was, and how it works are all unknown, but nobody dared to touch it. You see, when software is in operation for 50 years without failure it attains the status of "proven". No matter how many latent bugs remain in the proven software, we are pretty sure that they will never be triggered or cause a problem. Anything new, regarless of the time and money spent to perfect it, is "unproven."

Therefore, I predict, that after 10 or so years pass without new Dreamliner bugs causing failures, that nobody will ever dare touch it thereafter. Even if a previously unknown bug causes a crash 25 years from now, the risk of any remediation will be greater than the risk of doing nothing.
 
  • #173
anorlunda said:
Once again, this proves that all the kings horses and all the kings men can never make flawless yet complex software. There is no such thing and there never will be.

Agreed.

anorlunda said:
Therefore, I predict, that after 10 or so years pass without new Dreamliner bugs causing failures, that nobody will ever dare touch it thereafter. Even if a previously unknown bug causes a crash 25 years from now, the risk of any remediation will be greater than the risk of doing nothing.

Not sure about never touching it. Look at the Linux kernel. It could very likely be one of the most complex software codes out there. But bugs are still getting regularly fixed. And Linux kernels get eventually used in many fairly critical tasks.

So I guess although we can never certify complex code as "bug free" that doesn't stop us from carefully fixing bugs.
 
  • #174
Diminishing returns is a natural law .

On the other hand, it remains to be seen what will be the effect of this structure imposed by the machines on human language and thought.

I was the last of the "Slide Rule Generation" and well remember when Miami had only one TV station that was on only afternoon and evenings.
I've seen the "Sesame Street Generation" come to power in society.

Check out code.org and try their "hour of code" exercise - it's made for little kids but it's an absolute blast.
I wish i could live long enough to see what these computer generation kids do.

old jim
 
  • #175
oops- that was a hijack, wasn't it ?

They should fix that integer overflow.
and make sure it's a global variable.
220px-Great_Seal_of_the_United_States_%28reverse%29.svg.png
 
<h2>1. What caused the problems with the Dreamliner battery?</h2><p>The problems with the Dreamliner battery were caused by a combination of design flaws and manufacturing defects. The battery's lithium-ion cells were prone to overheating and catching fire, and the battery's casing was not strong enough to contain a fire if one occurred.</p><h2>2. How were the problems with the Dreamliner battery addressed?</h2><p>The problems with the Dreamliner battery were addressed through a series of safety improvements and modifications. These included redesigning the battery's internal structure, adding insulation and ventilation, and implementing stricter manufacturing processes to prevent defects.</p><h2>3. Has the Dreamliner battery issue been completely resolved?</h2><p>While the Dreamliner battery issue has been significantly improved, it is an ongoing process to ensure the safety and reliability of the battery. The Federal Aviation Administration (FAA) continues to monitor and evaluate the battery's performance, and additional modifications may be made in the future if necessary.</p><h2>4. Have other aircrafts experienced similar battery problems?</h2><p>Yes, other aircrafts have experienced similar battery problems, but not to the same extent as the Dreamliner. The FAA has implemented stricter regulations and testing procedures for lithium-ion batteries used in aircrafts to prevent future incidents.</p><h2>5. What impact did the Dreamliner battery problems have on the aviation industry?</h2><p>The Dreamliner battery problems had a significant impact on the aviation industry, causing delays and grounding of the Dreamliner fleet. It also highlighted the importance of thorough testing and safety measures for new technologies in the aviation industry.</p>

1. What caused the problems with the Dreamliner battery?

The problems with the Dreamliner battery were caused by a combination of design flaws and manufacturing defects. The battery's lithium-ion cells were prone to overheating and catching fire, and the battery's casing was not strong enough to contain a fire if one occurred.

2. How were the problems with the Dreamliner battery addressed?

The problems with the Dreamliner battery were addressed through a series of safety improvements and modifications. These included redesigning the battery's internal structure, adding insulation and ventilation, and implementing stricter manufacturing processes to prevent defects.

3. Has the Dreamliner battery issue been completely resolved?

While the Dreamliner battery issue has been significantly improved, it is an ongoing process to ensure the safety and reliability of the battery. The Federal Aviation Administration (FAA) continues to monitor and evaluate the battery's performance, and additional modifications may be made in the future if necessary.

4. Have other aircrafts experienced similar battery problems?

Yes, other aircrafts have experienced similar battery problems, but not to the same extent as the Dreamliner. The FAA has implemented stricter regulations and testing procedures for lithium-ion batteries used in aircrafts to prevent future incidents.

5. What impact did the Dreamliner battery problems have on the aviation industry?

The Dreamliner battery problems had a significant impact on the aviation industry, causing delays and grounding of the Dreamliner fleet. It also highlighted the importance of thorough testing and safety measures for new technologies in the aviation industry.

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