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New safety upgrades could make this possible

Boeing could have its 787 Dreamliner jets back in the sky in "weeks" instead of months thanks to a few new safety upgrades.

According to Boeing, the safety upgrades include improved production/operating processes, adjustments to the battery itself and a new enclosure for the battery.

"Our first lines of improvements, the manufacturing tests and operations improvements, significantly reduce the likelihood of a battery failure," said Mike Sinnett vice president and chief project engineer of the 787 program. "The second line of improvements, changes to the battery, helps stop an event and minimize the effect of a failure within the battery if it does occur. And the third line of improvements, the addition of the new enclosure, isolates the battery so that even if all the cells vent, there is no fire in the enclosure and there is no significant impact to the airplane."

Improved production/operating processes entails more rigorous testing. Boeing partnered with battery maker GS Yuasa and integrated power conversion system provider Thales to come up with new testing methods. Now, there are 10 different tests that battery cells must undergo over a 14-day screening period.

They've also adjusted the acceptable level of charge for the battery by lowering the highest charge allowed and raising the lowest level allowed.


As for the battery itself, two kinds of insulation were added: an electrical insulator and a thermal insulator, which will wrap around/below each battery cell to keep them away from each other and the battery case.

The wire sleeving and wiring within the battery were also upgraded to be resistant to heat and chafing. In addition, small holes were added to the bottom of the battery case to allow moisture to drain, and larger holes will allow the battery to vent if it fails.

As far as the new enclosure goes, it is made of stainless steel and will make sure no wire can ignite inside. It has a direct vent to carry battery vapors outside of the plane and isolates the battery from the rest of the equipment.

“It is reasonable to expect that we could be back up and going in weeks, not in months,” said Sinnett. “We understand the work to be done and we’ve got a fairly good notion of how long it will take, and if we miss, it will be by a little, not by a lot.”

Boeing's 787 Dreamliner suffered many issues back in Janury of this year. It started with a 787 operated by Japan Airlines, which had experienced an electrical fire at Boston's Logan International Airport after coming in from Tokyo. According to the National Transportation Safety Board, a battery in the auxiliary power unit suffered severe fire damage.

One day later, a Boeing 787 operated by the same airline at the same airport suffered a fuel leak.

Later,
a 787 Dreamliner with All Nippon Airways (ANA), which had arrived at the Matsuyama airport in western Japan from Tokyo on Friday, developed a web-like crack in the cockpit window. That same day, another 787 Dreamliner with ANA had an oil leak after traveling to the Miyazaki airport in southern Japan.

Finally, an ANA 787 flight to Tokyo had an issue with its main battery only 15 minutes into a 90-minute flight. After 40 minutes, a burning smell made its way into the cabin and cockpit, and the plane made an emergency landing at Takamatsu Airport on the southern island of Shikoku. This issue caused all 787s to be grounded in Japan, the U.S. and India until a safety investigation was conducted and the problems were corrected.

Source: Boeing



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stating the obvious
By Samus on 3/15/2013 12:17:13 PM , Rating: 2
I'm no aerospace engineer, but I am an engineer, and looking at the 'upgrades' I am as surprised as anybody else as to why these incredibly simple fixes weren't implemented in the first place. This is Boeing for Christ sake.




RE: stating the obvious
By Amiga500 on 3/15/2013 12:29:04 PM , Rating: 3
In a word - weight.

Tens of thousands are spent shaving a few lbs off here and there. [By few, I do mean <5!]


RE: stating the obvious
By M'n'M on 3/15/2013 12:32:18 PM , Rating: 4
But as an engineer you already know the answer(s) to your question; time and $$s. Management universally operates on the principle of not spending a penny today even it will cost them a dollar next week. It's one reason why Dilbert was understood by everyone.

The stated "fixes" appear to be more like band-aids than fixes. I can only hope that behind the scenes there's people at work on the real fix, one that addresses the root cause(s). These are rolled out to get the planes back in the air and stop the hemorrhaging of $$s and loss of sales to Airbus.


RE: stating the obvious
By Voldenuit on 3/15/2013 12:52:13 PM , Rating: 2
quote:
Management universally operates on the principle of not spending a penny today even it will cost them a dollar next week.


Ding! ding! ding! ding! ding! Give that man a dollar!

quote:
The stated "fixes" appear to be more like band-aids than fixes.


Agreed.

quote:
I can only hope that behind the scenes there's people at work on the real fix, one that addresses the root cause(s).


I'm afraid you already answered that question with your first paragraph. Management will be complacent about the bandaid fix until the next catastrophe happens.


RE: stating the obvious
By Dorkyman on 3/15/2013 1:50:53 PM , Rating: 2
Not fair.

You don't spend money to fix a "problem" if there is no problem to be fixed.

Yeah, NOW we can see that there are issues, but at the time it seemed all that had to be done was to make sure the batteries were not overcharged and they would be okay (okay, I'm simplifying a bit but that's the main idea).

How is it that an intersection often doesn't get a traffic signal until there's an accident there? Because there are millions of intersections and it would be financially impossible to put signal at every one of them.

My own suspicion is that Yuasa made some substandard cells but Boeing has probably wisely decided to design an environment where even a faulty battery can be tolerated.


RE: stating the obvious
By Voldenuit on 3/15/2013 2:31:22 PM , Rating: 2
quote:
How is it that an intersection often doesn't get a traffic signal until there's an accident there? Because there are millions of intersections and it would be financially impossible to put signal at every one of them.


By this analogy, the original 787 battery design, which had:
1. Known unstable chemistry
2. Potentially unsafe cell configuration
3. Inadequate fire and smoke containment and venting

would be analagous to building an intersection in a heavily trafficked region with:
1. No stop signs
2. No lighting
3. Runoff area is a ditch filled with stakes and man-eating crocodiles

Essentially, they designed an unproven and potentially unsafe configuration without a contingency plan in place other than "don't catch fire". I know it's tempting to be an 'internet battery expert' when commenting about the 787 woes, and that hindsight is always 20-20, but I can't even begin to see where due dilligence was done on the 787 battery in the first place.


RE: stating the obvious
By Solandri on 3/15/2013 4:17:31 PM , Rating: 3
quote:
By this analogy, the original 787 battery design, which had:
3. Inadequate fire and smoke containment and venting

To be fair, if you look at pics of the battery which caught fire, the battery is destroyed but the external case appears pristine. So apparently it had adequate fire and smoke containment (not so sure about the venting). In that respect there was no danger to the plane.

The problem was the batteries weren't supposed to catch fire in the first place, but they had two incidents within the first few months of service. Which led to a reassessment of the fire risk, forcing a redesign which assumed a higher frequency of fire. So now they're adding things like isolating different cells from each other so a fire doesn't spread as easily between cells.

Basically they've gone from "in the highly unlikely event of a fire, it will be contained," to "in the event of a fire, its effects will be mitigated by this, this, and this."


RE: stating the obvious
By GulWestfale on 3/15/2013 6:42:02 PM , Rating: 2
quote:
As for the battery itself, two kinds of insulation were added: an electrical insulator and a thermal insulator, which will wrap around/below each battery cell to keep them away from each other and the battery case.


wow... really... one would think that this would have been in place from the get-go, weight savings or not. safety should come first, as should extensive field testing.


RE: stating the obvious
By Voldenuit on 3/15/2013 8:09:43 PM , Rating: 2
quote:
To be fair, if you look at pics of the battery which caught fire, the battery is destroyed but the external case appears pristine. So apparently it had adequate fire and smoke containment (not so sure about the venting). In that respect there was no danger to the plane.


The smoke vented into the cabin in the Boston incidents as well as the Japanese one, which was a definite safety issue. You are correct that the fires did not damage any surrounding structures AFAIK.


RE: stating the obvious
By Fireshade on 3/19/2013 7:09:57 AM , Rating: 2
quote:
The problem was the batteries weren't supposed to catch fire in the first place, but they had two incidents within the first few months of service. Which led to a reassessment of the fire risk, forcing a redesign which assumed a higher frequency of fire. So now they're adding things like isolating different cells from each other so a fire doesn't spread as easily between cells.

Rightly put.
From other technological articles on the Dreamliner solution, you can tell that Boeing's fix only addresses the symptoms. They have not yet found and solved the problem itself, i.e. they still don't know why the batteries can become instable/overheated.

Apparently Boeing and its partners are comfortable with these kind of fixes, when money is at stake. Which is really bad, because it means that money is more important than intrinsically safe design.


RE: stating the obvious
By plu1357 on 3/16/2013 10:34:43 PM , Rating: 2
When I was a kid, an experienced engineer told me. To build a bridge which won't fall is engineering, while to build a bridge with minimum material but it still can hold up is the best engineering. Yeah these "band-aid" fixes might be don at the first place but the engineers thought they can get away without them.

Just reminded me about Ford Pinto. They had a bladder design for the gas tank to protect leaking at the early stage. But they cut corner to save a few bugs and maybe a pound or so. That result was disastrous.

Actually beyond these band-aid fixes, Boeing trimmed down the maximum charge and elevated the minimum discharge. These all reduces the battery efficiency (W/lb). But hopefully the change result still within spec and still better then Ni-Cd batteries.


RE: stating the obvious
By Reclaimer77 on 3/15/2013 4:27:39 PM , Rating: 2
Boeing didn't make the battery though. They got screwed by the supplier, obviously.

These are retrograde solutions because for Boeing to go in a completely different direction with a new supplier and battery and replace all of these batteries on every plane...would just be way too expensive and an unacceptable amount of time lost.

No "fixes" were needed originally because Boeing was told the batteries were supposed to operate at those voltages and conditions. Obviously that wasn't the case, so Boeing had to engineer a way around the suppliers fu#k up.


RE: stating the obvious
By Voldenuit on 3/15/2013 8:35:39 PM , Rating: 2
quote:
Boeing didn't make the battery though. They got screwed by the supplier, obviously.


But Boeing has the responsibility of testing the batteries. And validating the battery + charger (US supplier) + ancillaries package. According to the FAA, no flight tests were done to stress the battery (something which is being rectified with the new test plan).

Not to mention it was Boeing's decision to go for large, LiCoO cells.

Boeing can't completely escape culpability on this, because even if the root cause lay with the battery supplier, Boeing was still responsible for design and testing.


RE: stating the obvious
By Jedi2155 on 3/16/2013 5:18:23 AM , Rating: 2
As a battery engineer who regularly tests battery systems, this is complete onus at Boeing. Many of my own management were literally face palming when they found out the details regarding the conditions that led to this and the lack of safety precautions.

They believed this is partially due to Boeing deciding to outsource so many of their components and not thoroughly testing the system integration of it.

It is not completely the suppliers fault, but a large part of it is Boeing's management who decided to cut the amount of testing time available. I've met Boeing engineers and I know many of them are very capable. Given enough resources, I bet they would've found many "industry known" issues before the plane ever took flight.

This is not the only case I've heard of either of poor battery management practices....I've heard quite a few defense projects are pretty bad as well...

Apparently no one cares about batteries and thus they are typically poorly designed.


RE: stating the obvious
By Reclaimer77 on 3/16/2013 12:44:02 PM , Rating: 2
quote:
As a battery engineer who regularly tests battery systems, this is complete onus at Boeing.


Are we supposed to be surprised that you would have this opinion? lol. Not saying you can't be unbiased, but....

quote:
They believed this is partially due to Boeing deciding to outsource so many of their components and not thoroughly testing the system integration of it.


They can't seriously be that ignorant. So Boeing should have spent hundreds of billions making their own battery factory, staffing it, and producing batteries themselves? I would think the benefits of outsourcing here would be self-apparent.

quote:
It is not completely the suppliers fault, but a large part of it is Boeing's management who decided to cut the amount of testing time available.


I agree. But still suppliers should be held accountable when they deliver contract-bid components that are NOT to claimed specs.


RE: stating the obvious
By Jedi2155 on 3/16/2013 7:44:52 PM , Rating: 2
I was not trying to be biased, but the problem was that there were a lot of "basic" safety features that should be designed in battery systems which were not on this aircraft. I did not say that Boeing should spend money making their own battery cells, but maybe their own management system....or at least more testing.


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