Sunday, April 21, 2013

Solution to Boeing 787 Lithium-Ion Battery Fire: Containment and Venting


Hmmm... Sounds strangely familiar, doesn't it?

Following the FAA approval, Boeing has begun the repair of five Boeing 787 Dreamliners owned by All Nippon Airways (which owns total 17).

Have they figured out what actually caused the battery fire? No they haven't. If they have, they haven't told us.

What about the miswiring in ANA's plane, where the main battery and the auxiliary battery were connected but they shouldn't have been connected? Have they fixed that one?

From Reuters (4/21/2013):

UPDATE 1-Boeing begins fixing Dreamliners, starts on five ANA 787s

* Some 787s should be ready to fly again in about a week

* ANA plans 100 to 200 round trip test flights in May

* The grounding has cost Boeing an estimated $600 million

TOKYO, April 22 (Reuters) - Boeing Co on Monday began installing reinforced lithium ion batteries on five grounded 787 jets owned by launch customer All Nippon Airways, starting a process that should make the first commercial Dreamliners ready to fly again in about a week.

Teams of Boeing engineers are working on the ANA jets at four airports in Japan, including Tokyo's Haneda and Narita hubs, Ryosei Nomura, a spokesman for the carrier said.

The Dreamliners have been parked since regulators in the United States and elsewhere ordered all 50 planes out of the skies in mid-January after batteries on two of them overheated.

ANA is the world's biggest operator of the carbon-composite aircraft with 17 of the planes. After ANA, the biggest 787 operator is local rival Japan Airlines Co with seven jets, followed by United Continental Holdings Inc's United Airlines and Air India with six each.

ANA plans about 100 to 200 round trip test flights in May of its repaired aircraft before carrying passengers again from June, sources knowledgeable about ANA's operations told Reuters last week. The flights will check the safety of the aircraft, and allow ANA's 180 Dreamliner pilots to get accustomed to flying it again and renew their licenses after more than a three-month break.

ANA has not said how much the 787's grounding has cost it to date, though it has said it lost about $900,000 in revenue per plane in the last two weeks of January. The grounding has cost Boeing an estimated $600 million.

The Federal Aviation Administration (FAA) in the U.S. on Friday approved a Boeing plan to encase the 787s lithium ion batteries in steel box, install new battery charges, and add a duct to vent gases directly outside the aircraft that could cause overheating.

Investigators in the United States and Japan have yet to unravel what caused a 787 battery onboard an ANA jet in Japan and one on another JAL Dreamliner parked at Boston's Logan Airport to overheat.

8 comments:

Anonymous said...

If the technology and properties of a battery can't be understood, what does this say about nuclear energy?? Ooh jee :)

Anonymous said...

If they can't run a fertilizer plant safely, what does this say about NPPs? Oh Jesus :(

Anonymous said...

Did they test them at altitude?

Is it the Lithium that interacts with the increased solar radiation or was it poor design?

You wouldn't want to be leaving on a jet plane if the engineers built it without understanding the properties of the periodic table.

Anonymous said...

Well, they did not fix the problem at its root so further testing will occour on the battle field. Anyways no one has yet died as a direct consequence of a battery fire, so we can assume they are safe.

Beppe

Atomfritz said...

Flight Captain announcement:

Ladies and Gentlemen, I have to announce that we have a small problem with our molten lithium salts electricity plant. The power plant has been safely shut down, is contained and venting is in progress. I apologize for the inconvenient, but harmless smell. So, please don't be disturbed by baseless health worries. Enjoy your flight!

Anonymous said...

What i want to know is have the Navy relaxed the ban on Tritium vial illumination of wristwatches in their submarines?

My electronics lecturer in the 80's mentioned that watches with radionuclides were not allowed then as they would tip the exposure scale too far.

He was a Microwave specialist before joining the teaching profession.

Do they wear these watches or do they wear Casio's?

Anonymous said...

The cause of internal short circuits in all lithium-ion batteries is the ingression of the air pollutant formaldehyde and water vapour into the battery, as air pressure increases. On standing,as the temperature inside the battery drops to the dew point,liquid water forms and the formaldehyde then polymerises to form an electrically conducting strand of polymer between opposite charged terminals - hence voltage drops to zero and thermal runaway commences. But who wants to check out this scenario?

Anonymous said...

Well,if i was a Submariner i wouldn't like to think the nuclear vessels in service are so prone to springing a leak that the various rear admirals don't really care if we were Traser or not.

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