Boeing lithium batteries

[Richard Henry]

Does anyone have a pointer to a good technical discussion of the
Dreamliner batteries?

 

[Richard Henry]

Follow articles in Aviation Week, The Wall Street Journal, and The New
York Times.  Eventually there will be a comprehensive report from the
FAA and/or the NTSB.

The article in WSJ this morning said that the cause was traced to a
battery cell shorting itself.  Why the cell shorted is not yet known,
but my guess is that vibration and bumps on landing are involved, mainly
because most test labs do not fly, so flying is what's new.  Another
possibility is voltage spikes on the power busses due to the normal
operation of something else in the airplane (other than the charging
system).

Another article said that the FAA is pissed off at Boeing because their
safety analysis was clearly deficient.

Joe Gwinn

Thanks for the suggestions, but I was hoping for something beyond the
front-page ignorance.

What is not new is the corporate incentive to pass tests without any
problems such as added cost or schedule delays. The most valuable
employee a big company can have is the engineer who asks "But what
if...?"

 

[petrus bitbyter]

No but rumor goes the current plan is to do away with re chargeables,
and buy new Duracells before each flight:

Yeah, but this plan has been cancelled or so I heard. They'd have to get rid
of a vast number of exhausted batteries. This batteries could easily be
dropped in the ocean when they fly above it but it seems Green Peeche
protested and threatened to boycot the planes.

petrus bitbyter

 

[[email protected]]

Test labs do have vibe tables, though, and airplane designers do specify
vibe and shock standards for avionics.  Everything is expected to not
only be designed for shock and vibe, but to be thoroughly tested.

Perhaps the difference is that they didn't shake things for 10 hours to
simulate a trans-Pacific flight.  I dunno.  But you can bet they were
specified, designed, and tested for vibe.


Again, this is a known phenomenon in avionics, and you design your boxes
to withstand such, then test the hell out of them before you ship.  If
your customer is smart, they review your results, too.


The FAA tends to have a "blame the victim" mentality.  If you go flying
and you crash because you did something, it's pilot error.  If you go
flying and you crash because your equipment broke, then unless your
mechanic seriously pulled the wool over your eyes it's pilot error
because you took off with faulty equipment.  If you go flying and you
crash because of bad weather, it's your fault because you didn't pay
attention to the weather.  "Shit happens" is not a phrase to be found in
the FAA dictionary.

that's probably a good thing, their job it to find reasons for
accidents
and try to prevent them from happening again

remember one of the investigators on "air crash investigations"
saying
"pilots get too much of the glory and but also too much of the
responsibility"

Obviously, if Boeing did a safety analysis that said the batteries were
OK, and they failed anyway, then ipso facto (by FAA logic) Boeing's
safety analysis was clearly deficient.  Heaven knows -- the FAA may even
be right.

clearly something went wrong, Boeing estimated less than one event
per 10million flight hours, now they've had two in fewer than 100,000


-Lasse

 

[[email protected]]

Obviously, if Boeing did a safety analysis that said the batteries were

OK, and they failed anyway, then ipso facto (by FAA logic) Boeing's

safety analysis was clearly deficient. Heaven knows -- the FAA may even

be right.

NTSB is conducting the investigation, not FAA. FAA has been put on the spot by NTSB and will eventually have to explain their approval of the Boeing testing. FAA and Boeing are both in the same pot of hot water.

 

[[email protected]]

My theory/guess is that a cell shorted internally because of some

anomoly of operating at high altitude.

Yeah, since they are in the Yuasa aviation high reliability line, they would never have thought about the altitude thing...

 

[[email protected]]

Joseph Gwinn wrote:








I think that every airline that paid $200 - 250 million each is also pissed

at Boeing, and will be exercising their rights under their contract to

collect damages for their grounded planes.



Jon

Didn't the US government loan them (taxpayer) money to buy the planes in the first place? They'll just put an interest free moratorium on the payment schedule.

 

[TTman]

The article in WSJ this morning said that the cause was traced to a
battery cell shorting itself. Why the cell shorted is not yet known,
but my guess is that vibration and bumps on landing are involved, mainly
because most test labs do not fly, so flying is what's new. Another
possibility is voltage spikes on the power busses due to the normal
operation of something else in the airplane (other than the charging
system).

Another article said that the FAA is pissed off at Boeing because their
safety analysis was clearly deficient.

Joe Gwinn

Anything we do , to do with aircraft electronics is subject to strenuous
vibration and temperature cycling over a period of days. Mind you, it's 99%
Military... but I would have thought the same things/rules apply to civil
aircraft ?
I would have thought tests would be at least as stringent- many lives are at
risk....

 

[John Miles, KE5FX]

that's probably a good thing, their job it to find reasons for
accidents
and try to prevent them from happening again

remember one of the investigators on "air crash investigations"
saying
"pilots get too much of the glory and but also too much of the
responsibility"


clearly something went wrong, Boeing estimated less than one event
per 10million flight hours, now they've had two in fewer than 100,000

(Shrug) Give them 19,900,000 more flight hours and they could still
meet spec!

-- john

 

[MrTallyman]

But better is an airplane that is stable all by itself,
and you can land as a glider... when no power.

To use a TLJ line from MIB "Try it" -K

I think you are a goddamned idiot who has zero capacity to see the
bigger picture in anything.

Try landing a 100% full to capacity craft of ANY design sans power.

It ain't fun, and you better be the best fucking physicist/pilot there
is. And think on your feet real fast.

Go back to your Balsa wood, rubber band powered gliders, child.

 

[MrTallyman]

The only hope now is on China, they are designing their own airplanes,
and soon you will be able to buy those on ebay for a fraction of the price of a dreamplane.
Probably nuclear powered electric engines...

You are a true idiot. Why don't you go there, if you are so hep on a
communist regime that got EVERYTHING handed to it or they stole it.
And they still do.

 

[Spehro Pefhany]

On Fri, 8 Feb 2013 18:12:14 -0800 (PST), the renowned

Didn't the US government loan them (taxpayer) money to buy the planes in the first place? They'll just put an interest free moratorium on the payment schedule.

They've also got the tanker boondoggle to tide them over. $52bn is a
considerably subsidy.


Best regards,
Spehro Pefhany

 

[[email protected]]

Didn't know that. Where did you see that ? Of course none of the

news or EE sites I saw said anything about that. Yuasa's been making

batteries for quite a while. I would think they would be one of

the best for this. Two installs and possibly two internally shorted

batteries and BMS is supposedly been weeded out as a problem.

http://www.gsyuasa-lp.com/

Go to Products-> Cells for Aviation -> LVP 65

 

[[email protected]]

On Saturday, February 9, 2013 8:21:49 AM UTC-5, MrTallyman wrote:

<snip rant>

This "MrTallyman" sounds an awful lot like that KRW troll ...

 

[[email protected]]

They've also got the tanker boondoggle to tide them over. $52bn is a

considerably subsidy.





Best regards,

Spehro Pefhany

--

"it's the network..." "The Journey is the reward"

[email protected] Info for manufacturers: http://www.trexon.com

Embedded software/hardware/analog Info for designers: http://www.speff.com

"Unethical conduct
In May 2003, the U.S. Air Force announced it would lease 100 KC-767 tankersto replace the oldest 136 of its KC-135s. In November 2003, responding to critics who argued that the lease was more expensive than an outright purchase, the DoD announced a revised lease of 20 aircraft and purchase of 80. In December 2003, the Pentagon announced the project was to be frozen while an investigation of allegations of corruption by one of its former procurement staffers, Darleen Druyun (who began employment at Boeing in January) was begun. The fallout of this resulted in the resignation of Boeing CEO Philip M. Condit and the termination of CFO Michael M. Sears.[35] Harry Stonecipher, former McDonnell Douglas CEO and Boeing COO, replaced Condit on an interim basis. Druyun pleaded guilty to inflating the price of the contract to favor her future employer and to passing information on the competing Airbus A330 MRTT bid. In October 2004, she received a jail sentence for corruption.[citation needed]

In March 2005, the Boeing board forced President and CEO Harry Stonecipher to resign. Boeing said an internal investigation revealed a "consensual" relationship between Stonecipher and a female executive that was "inconsistent with Boeing's Code of Conduct" and "would impair his ability to lead the company".[36] James A. Bell served as interim CEO (in addition to his normal duties as Boeing's CFO) until the appointment of Jim McNerney as the new Chairman, President, and CEO on June 30, 2005."

 

[MrTallyman]

No

Terrell has to cry like the baby he is at least once a day.

 

[[email protected]]

On Sat, 9 Feb 2013 06:33:01 -0800 (PST),

On Saturday, February 9, 2013 8:21:49 AM UTC-5, MrTallyman wrote:

<snip rant>

This "MrTallyman" sounds an awful lot like that KRW troll ...

Ever look in a mirror, troll?

 

[Jasen Betts]

The problem is that it's still too soon for much else.



I don't buy that the problem is because Boeing wanted to cut corners on
the tests. Having a public problem like this costs many times more than
the entire battery system costs, and the battery system is a trivial
fraction of the cost of the airplane.

Something was simply missed while pioneering use of big lithium
batteries on aircraft. Somehow, the test setup does not capture
something essential about actual operating conditions.

By the way, this battery is not as large as for an electric automobile.

Smaller than a truck battery I'll buy that.

Is the scale in that photo centimetres and inches ?

 

[Jasen Betts]

Don't know, but there was a picture of a burned-out battery box with an
engineer inspecting it, so one can get the general scale from that
photo. The box didn't seem that large. The size and weight was also
published, but I don't recall where I saw it.

I found this photo with an engineer
http://graphics8.nytimes.com/images/2013/01/24/business/Boeingjp/Boeingjp-articleLarge.jpg

the one with the scale was like this.

http://money.cnn.com/2013/01/17/technology/boeing-battery/index.html

here is a "before" image:

http://www.newsdaily.com/stories/bre90m002-us-boeing-787-hearing/
http://www.newsdaily.com/photos/2013-01-23T004358Z_3_CBRE90M005500_RTROPTP_3_BOEING-DREAMLINER.JPG

10" x 7" x 12"
253mm 178mm 305mm

car battery:
http://www.centurybatteries.com.au/search/index.php/batteries/ID-84

230mm x 173mm x 134mm

so it's over twice the volume of that one

 

[YD]

Late at night, by candle light, MrTallyman

To use a TLJ line from MIB "Try it" -K

I think you are a goddamned idiot who has zero capacity to see the
bigger picture in anything.

Try landing a 100% full to capacity craft of ANY design sans power.

It ain't fun, and you better be the best fucking physicist/pilot there
is. And think on your feet real fast.

Go back to your Balsa wood, rubber band powered gliders, child.

http://en.wikipedia.org/wiki/Gimli_Glider

- YD.