Japanese Probe Finds Miswiring of Boeing 787 Battery
NeverVotedBush writes in with the latest installment of the Dreamliner: Boeing 787 saga. "A probe into the overheating of a lithium ion battery in an All Nippon Airways Boeing 787 that made an emergency landing found it was improperly wired, Japan's Transport Ministry said Wednesday. The Transport Safety Board said in a report that the battery for the aircraft's auxiliary power unit was incorrectly connected to the main battery that overheated, although a protective valve would have prevented power from the auxiliary unit from causing damage. Flickering of the plane's tail and wing lights after it landed and the fact the main battery was switched off led the investigators to conclude there was an abnormal current traveling from the auxiliary power unit due to miswiring."
Who will it be? Maintenance? Boeing?
Can't they make an idiot proof power plug?
http://en.wikipedia.org/wiki/Japan_Transport_Safety_Board
http://www.mlit.go.jp/jtsb/english.html
Report is in Japanese, so feed the link to your favorite translator. Just now, Google returns "Sorry, we are unable to translate the page you requested." Which'd be fine if they didn't offer the "Translate this page" link, then take a while processing. Boneheads.
http://www.mlit.go.jp/jtsb/flash/JA804A_130116-130220.pdf
So basically, the user reached back behind the power supply while fiddling and bumped the 110/220V switch, and it caught fire. Naturally, they didn't say anything to the tech after setting the switch back besides, "It just caught fire! All by itself!"
The user in this case is a giant airline company, and tech support would be Boeing. The FAA, of course, is the QA manager, who reviewed the call, and after reading the ticket closure notes, facepalmed, leaned back into his chair, and took a deep draft of coffee.
#fuckbeta #iamslashdot #dicemustdie
I haven't seen enough hentai to know where this is going...
It's the damned metric +/- that causes all the confusion.
"the battery for the aircraft's auxiliary power unit was incorrectly connected to the main battery that overheated, although a protective valve would have prevented power from the auxiliary unit from causing damage"
What is a power diode
AccountKiller
The Japanese are doing everything they can to point blame away from Yuasa. As someone above noted, and, yes I did read the fine article, they have concluded that it must have been wired incorrectly after seeing some lights flicker and a white dove flying in the southern quadrant.
What the fuck are you talking about? There are cannon plugs all over the place. The reason you think "directly hardwired" is because almost each LRU has its own circuit breaker. You must be one of the fucking PHBs
It's gonna be fun to watch. Whistleblowers are starting to emerge telling of how safety issues were swept under the rug in the name of getting an already late project out, and engineering concerns were ignored or overridden by managers. It's very similar to the story of the O-rings on the Space Shuttle, where engineers knew there were problems, but their concerns were ignored.
Gonna be a real show over the next year as these people start coming out in greater numbers.
When you say "Japanese Probe" I had an entirely different idea in my head regarding what this story was about.
They are wired together with bolts and screws, often coded so you need the right tools,
FRUs are socketed, the inside hard wired
simple, MFG, omb
Pick on something, question it's validity and then suggest conspiracy... are you Elon Musk?
"The Transport Safety Board said in a report that the battery for the aircraft’s auxiliary power unit was incorrectly connected to the main battery that overheated"
The lights flickering is a secondary indicator, the primary indicator is the actual miswiring!
The technical workers authorized a strike. Just watch Boeing goad them into it for a few weeks. They have a clause in their sales contracts relieving them of late delivery penalties due to circumstances beyond their control. Like strikes.
The contract will magically be settled after the engineers design a fix and its ready for manufacturing.
For the Prius accelerator screwup....
Presumably the same person who miswired the Japanese 787 miswired at least one other plane. That should be easy to check. If there are other planes with smoking batteries, check the wiring, then do it for all other 787s.
In a time of universal deceit, telling the truth is a revolutionary act. George Orwell
Nikkei is reporting that this miswiring, which connected the auxiliary and main batteries by mistake, is due to a bug in an older version of the 787's electrical design. The bug was found and fixed in November 2011, but somehow Boeing never got around to re-wiring this particular aircraft according to the new plan. Nikkei also reports that the miswiring probably did not cause the battery fire, because there is some sort of an "anti-reverse current mechanism" in place to prevent damage even if the auxiliary had started to feed current into the main battery.
Re: The battery cells are rectangular with a stud on each side of the top. Not even any prominent markings to indicate polarity, though the two studs seem to be mounted with different colored rivets.
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The other possibility is that the installer was color blind and has been able to get by without that disability showing through. Most items that are color-marked often have a redundant marking that is not dependent on color vision perception (except for resistors and their color banding indicators, http://en.wikipedia.org/wiki/Electronic_color_code#Resistor_color-coding and for cable runs of twisted-pairs that use paired coloring indicators
You need a blow-out panel.
The M1A2 Abrams tank has one for the shells. If they start to burn, the blow-out panel pops off and the whole mess exits the tank.
Factories that make vinyl have them. When the concoction goes boom, blow-out panels prevent total destruction of the building. Workers may even survive.
Meth labs don't have them. :-)
A reasonable design would have several battery compartments, each with a separate blow-out panel. These should be located so that debris will not enter the engines or get run over by the landing gear. The rear underside seems like a good location.
Series for 240V input, parallel for 120V, but otherwise you are correct ;)
This reminds me of when I was having a new furnace installed. The installer wiring up the thermostat was having a hell of a time because he was color blind (I helped him out there).
Looking at the pictures here though even a color blind person should be able to easily tell positive from negative on the battery terminals.
This post is encrypted twice with ROT-13. Documenting or attempting to crack this encryption is illegal.
Did they try turning it off and on again?
I see that the discussion here is based on a sketchy summary from the originally Japanese press conference. More coherent information is available if you could read Japanese but I know it's too much to ask for...
Here is the latest update of the on-going investigation from the JTSB issued 20 Feb, 2013; this mentions the mis-wiring:
http://www.mlit.go.jp/jtsb/flash/JA804A_130116-130220.pdf
More in-depth information is given at
http://www.aviationwire.jp/archives/16032
According to this article, the mis-wiring was in the original specs/design, and the design had been corrected. The aircraft in question was manufactured in accordance to the earlier specs but no modification was made to comply with the new ones. One can infer that the bug was considered insignificant to compromise the safety of the aircraft. The JTSB currently does not think this mis-wiring was the cause of the battery incident although they will keep looking into it as a potential cause of anomalous voltage readings.
..they will add fire-proof coffins with vents for their batteries in case they decide to burn themselves off. Nice. Very Nice.
But yeah, that might be a proper engineering solution, provided that the "coffin" actually works as advertised. I can already see the PHB doctoring the test scenarios. "There will never be so many cells being shorted at the same time ! We don't need that scenario !"
In the case of the A380, wiring caused only delays in the design and manufacturing processes.
The BRITISH tried to crash an A380 by means of a little fire plus high-speed explosion of a Rollys-Royce engine, though. The shrapnel destroyed so many systems the pilots needed one hour to read all the failure report console. Meanwhile they let off fuel and brought the thing down again.
Rolls-Royce also had a problem with an ice-clogged fuel filter (from normal water in the fuel) and that made a 777 do a nasty crash-landing at heathrow.
All the joys of Margret Thatcher and The Market Will Fix It By Itself.
You type like comic book characters speak.