787 fire at Boston Logan

Nickel Metal Hydride is the best option in this case.

 

What people forget about "typical" electrical fires is they will continue to re-start and burn as long as they are being fed electricity. You have to kill the juice first then put out the fire.
Add Lithium Ion batteries and it's double jeopardy.

 

PUBLIC DOMAIN SOURCE
http://seattletimes.com/html/businesstechnology/2020505762_ntsb787reportxml.html


NTSB: Boeing outsourced key 787 battery safety analysis

The safety agency released its findings Thursday on its investigation of the Japan Airlines 787 fire at the Boston airport on January 7.

By Dominic Gates

Seattle Times aerospace reporter


Boston airport firefighters encountered sizzling liquid and a hissing, “exploding” battery when they entered the 787 at the center of a two-month-long National Transportation Safety Board investigation, according to documents released Thursday.

The NTSB said Thursday it plans two public hearings next month, one to explore lithium-ion battery technology in general and another to discuss the design and certification of the Boeing 787 battery system.

But the NTSB still has found no root cause of the battery fire on a Japan Airlines 787 fire at the Boston airport on January 7.

“The NTSB’s investigation into the probable cause ... is continuing,” the safety agency states in an interim factual report and 499 pages of related documents on its investigation.

Among the findings in the documents released Thursday:

• Boeing outsourced key analysis and testing of the battery system’s safety to its subcontractor, Thales of France, and to the battery maker, GS Yuasa of Japan.

Winning Federal Aviation Adminstration (FAA) certification for the 787 entailed a Battery Functional Hazard assessment, a Fault Tree Analysis, a Failure Mode and Effects Analysis and a Battery/Battery Charger System Safety Assessment.

“These analyses and tests were performed by Thales/GS-Yuasa and reviewed by Boeing,” the NTSB states.

• Boeing did its own separate safety assessment of the entire electrical power system that “also included an analysis of lithium-ion battery cell failure modes.”

Its analysis determined that “overcharging was the only known failure mode” that could result in fire. Boeing therefore built safeguards into the system to “to ensure that the likelihood of occurrence of an overcharge event” was less than one in a billion — which is the usual FAA standard in providing for potentially catastrophic events.

However, there is no indication in the NTSB documents that the battery that caught fire was overcharged.

Investigators inspected a hefty electrical contactor — a relay switch — that is part of the battery management system and was designed to open the electrical points and disconnect the cells in the event of an overcharge.

The heavily blackened contactor was found to be “in the de-energized closed orientation,” meaning that no overcharge had registered with the system and the contactor had not disconnected the cells.

• The NTSB a month ago established that the fire instead started with an internal short circuit of a single cell in the eight-cell battery.

Boeing’s pre-certification testing did try to evaluate the effect of an internal short circuit. In this test, a cell was punctured with a nail to induce a short circuit.

“This test resulted in venting with smoke but no fire,” the NTSB reported.

Boeing also consulted with other companies about their experience with the use of similar lithium battery cells and “based on this information, Boeing assessed that the likelihood of occurrence of cell venting would be about one in ten million flight hours.”

The 787 that caught fire in Boston had logged just 169 flight hours, the report states.

And the entire operational fleet of 787s had logged a total of 51,662 in-service hours, plus about 6,000 flight test hours.

• Testing of the battery charging unit (BCU) system was done by a Thales sub-contractor, Securaplane of Tucson, Ariz.

Early developmental testing of this system resulted in a major battery fire in 2006 that burned down a Securaplane building. After this, actual batteries were used only for isolated tests, with most of the testing instead using equipment that provided an electrical load representative of what a battery would provide.

The NTSB notes that there doesn’t seem to have been any testing of the charging system and battery together as an integrated system inside the airplane.

“No records have been seen that documented the performance of the individual Li-ion battery cells in testing that involved a battery/BCU set or in a complete Model 787 airplane,” the NTSB report states.

As part of its investigation, the NTSB last month began integrated system tests at a Boeing lab in Seattle. It is still doing data review and analysis.

• On the day of the Boston fire, the battery did not behave as Boeing or subcontractor Thales predicted.

The battery’s power discharge was “not at the constant rate described by the Boeing or Thales documents and included large changes and reversals of power within short periods of time,” according to the NTSB’s preliminary report.

• Sitting on a rack above the battery that burned was a smaller lithium ion battery, also supplied by Japanese manufacturer GS Yuasa, that is used to provide emergency power for the jet’s flight controls “for a minimum of 10 minutes when no other electrical power is available.”

Investigators found the exterior of this battery had been “lightly scorched” by the fire below and noted that its case had openings at the corners.

• No heat damage was found to any primary airplane structure.

However, the floor panel and carbon fiber floor support material, which are considered to be secondary structure, “were found to be heat damaged beneath where the APU battery had been installed.”

• The firefighters who were called to put out the fire did not know they were dealing with a lithium-ion battery, and had great difficulty putting out the intense fire.

When Capt. Mark Munroe of the airport’s aircraft rescue and firefighting (ARFF) unit entered the plane, he “saw heavy white smoke billowing through the floor” of the passenger cabin.

After locating the fire inside the electronics bay in the belly of the airplane, firefighters entered the compartment through dense smoke and applied shots of Halotron fire extinguisher to the battery.

Lt. David Hoadley of the ARFF unit reported that “It seemed like the fire did not want to go out, it kept rekindling.”

Then the battery “exploded,” according to Capt. Monroe.

“Capt. Munroe heard the battery hissing still and pushing white smoke or steam. There was liquid sizzling over the sides of the battery and still heavy smoke conditions. ... The battery continued to hiss before exploding.”

Monroe related that “he felt something hit him in the neck while he was in the airplane,” and he was sent out for medical treatment. “Something had burned his neck.”

Firefighters attempted to remove the battery from the jet, but found that the “quick disconnect” mechanism Boeing had included to allow mechanics to take out the battery for maintenance was “melted and un-recognizable” and a metal plate was preventing access.

The battery had to be cut out from the rack where it sat.

“With a hot battery and a gloved hand (Lt. Hoadley) could not access the bolts on the lower rails with tools. They attempted with pliers to remove the bolts for maybe 20 minutes. What looked like Teflon slides were burnt away and the battery would not move. There were 3 more screws that could not be removed.”

Firefighters cut away the metal plate, severed the battery wire, then “pried the battery loose with hydraulic spreaders and removed it.”

The battery was passed down to a firefighter and placed on the tarmac about 50 feet from the airplane.
The fire was declared under control an hour and forty minutes after the initial notification.

Boeing’s entire fleet of 787s has been grounded since a second battery incident during a flight in Japan, a week after the Boeing fire.

The company’s proposed fix for its battery system is currently under review by the FAA.

The agency expected to make an initial recommendation next week that will lay out a testing and certification path toward getting the airplanes back into service with airlines.

 

Could/would the FAA recommend switching to NiMH?

 

That would be highly unusual. The vendor proposes the engineering, and the FAA decides if it's safe as designed. Usually the FAA will just keep saying no, no, no, no, no until the vendor gives up.

Happened with Beech on the Starship which was the first all composite plane. The FAA kept rejecting it until Beech added so much structure it gained about 800Lbs. Then, they finally certified it, and the performance was crap, so it didn't sell. Now, composites are everywhere.

 

Doc has it right.
They aren't really in the business of making recommendations.

 

This airplane has suffered significant damage

 

Holey-moley! The news just keeps getting worse it seems.....

Probably. Certainly not as 'volatile' as Nimh. However, I've had one of those (in a laptop) heat up and 'swell'...... Still gotta have a 'smart' charger and no abuse or they'll do the same.

+1

Nasty things to put put, even once the power is killed, as the firefighters discovered it seems. Do these guys get any 'model specific' training in such areas? Sounds like they really didn't know what to do/use to fight the sucker?

Cheers,
Ian

 

The Firemen did not know they were fighting a Lithium Ion fire, at least not at first.
At the end of 1 hour and 40 minutes they did.

 

Not much about all of this in the MS press, so I assume that Boeing must be doing lots of 'damage control' in the background. They'd better, because if/when this gets picked up by the "journalists", the SWHTF. Would not be impossible these days to lose 50 years of well-deserved reputation in about 1 year.

That said; how many pax really would even know what their equipment was, without reading the cards in the seatback pockets?

 

And.... another blow to the body for Boeing. NTSB going to hold a forum and hearing in mid and late APRIL. We keep hearing from the people at Boeing that the fix is in, the tests will confirm and the plane will be back in service in no time!

Well, if they have the hearing a month+ from now, and the results of that hearing will have to filter out to the engineers, and then they develop a program, and then test it - I'm thinking this giant turd will not be laid until summer-ish.

NTSB Plans April Hearing And Forum On 787 Battery

 

Most of the airlines have taken the 787 out of their schedules through the end of May already.
They know the ramifications of this issue just as well as Boeing, regardless of what they have been told and what the press has been told.

 

This is both unbelievable and completely inexcusable:
______________

• Testing of the battery charging unit (BCU) system was done by a Thales sub-contractor, Securaplane of Tucson, Ariz.

Early developmental testing of this system resulted in a major battery fire in 2006 that burned down a Securaplane building. After this, actual batteries were used only for isolated tests, with most of the testing instead using equipment that provided an electrical load representative of what a battery would provide.

The NTSB notes that there doesn’t seem to have been any testing of the charging system and battery together as an integrated system inside the airplane.

“No records have been seen that documented the performance of the individual Li-ion battery cells in testing that involved a battery/BCU set or in a complete Model 787 airplane,” the NTSB report states.

 

Can you imagine how this is going to go down at the forum?:

"So, Mr Smith, from Securaplane, how did the initial testing with the battery go?"

"Well, we had complete success after an early setback."

"Can you describe the setback Mr Smith?"

"Uh - well, we um hooked up the Lithium battery to our charging unit and ran the steady state and variable load tests. It was initially successful, but we had a small setback."

"What was the result of the setback/"

"The -ah, building burned to the ground."

"I see, and what did you do then?"

"Oh, well after that, of course we tested the whole system without the actual battery. See, we used a carbon load cell to mimic an actual Lithium battery in there."

"Why did you not use the Lithium battery in the following tests?"

"Well, the first set fire to the building and all the test equipment, it was just too dangerous to use the actual battery."


lol,,,, what a carve up.

 

I think that Boeing has to surrender to what I think will be inevitable: a switch to NiMH batteries. Yes, there will be a weight hit, but there will be one with the current batteries, anyway, once that they find out that they have to build a "sarcophagus" around them.....

 

I read about this shortly after the grounding. The article mentioned that the fire was due to an incorrect test procedure or setup. Sounded fishy at the time, and still does. The added statement regarding subsequent testing, to me, confirms that that was just an excuse.

In other news
ANA says it had Dreamliner power distribution panel trouble 3 times ? Japan Today: Japan News and Discussion
"All Nippon Airways had three instances of electric distribution panel trouble in its Boeing 787 Dreamliner before it grounded the aircraft in January and had to replace the panel twice, a spokesman said Wednesday.

In the most serious case, which took place in April 2012, ANA found burns in the protection circuit and the breaker of an electric distribution panel during on-ground inspections after pilots received a generator-related bug message, ANA spokesman Etsuya Uchiyama said"

Although they go on to state that this is not a serious issue, and occurs in other airplane types, the fact that Boeing a an inflight fire in a distribution panel during flight tests and UAL made an emergency landing due to a cockpit indication makes me think otherwise. This airplanes electrical system is not the same as other airplane types. While this and the battery issue may not be related, it does highlight the extent the new system architecture on this airplane and its role in safety of flight.

 

What? They're now suggesting that circuit breakers & distribution panels now burn up "regularly"!..... WTF? And this isn't batteries going up but apparently something different altogether - I guess too much current draw/charge (the usual cause of these failures of course) but that simply should not happen - These are *protection* circuits!

This hole is just getting bigger & bigger IMO.

Cheers,
Ian

 

Oye-vey. Did I say summer-ish back in the air? What I meant was fall, maybe winter... With non Li+ batts in place.

It's gonna require an STC, testing, validation hours, then approval, then retro the fleet, then required mod of the supplement to existing airframes. What a CF.

 

Surely this plane is now doomed. Surely everybody will be cancelling orders and we will never see another 787 fly.

They better tool up to pump a few more 747s out ...

AirBus must be loving this!
Pete

 

As mentioned earlier in the thread in an article by an Engineer familiar with the airplane, the REAL problems are going to manifest themselves in the electrical panels because the parts are of cheap "Radio Shack" quality, also designed and built by a subcontractor.

A new article.
PUBLIC DOMAIN SOURCE

http://seattletimes.com/html/businesstechnology/2020496541_787japancircuitsxml.html



Pilots union officials highlight 787 power- panel concerns

Power-distribution-panel circuit boards were damaged on three ANA 787s last year, Japanese union officials said Wednesday.

By Dominic Gates

Seattle Times aerospace reporter


Japanese aerospace union officials cast new light on problems with the 787’s power distribution panels Wednesday, saying one malfunction last year caused a burned circuit board and disclosing two other previously unpublicized incidents.

Power panel faults, while unrelated to the battery problems that have grounded the 787 since mid-January, are another nagging issue with the plane’s innovative electrical system.

On flights in March, April and June of last year, faults in power-panel circuit boards on Dreamliners operated by Japanese carrier All Nippon Airways (ANA) resulted in error messages in the cockpit, said airline spokeswoman Nao Gunji.

Each time, the panels were inspected after landing. In the case of the fault on an April 7 flight, a circuit board was found to have shorted, causing “slight discoloration” from burning, Gunji said.

ANA replaced all three circuit boards, she said.

The Japan Federation of Aviation Workers’ Unions, which represents ANA pilots, highlighted the incidents at a press conference in Tokyo Wednesday.

Shozo Tsue, the federation’s secretary-general, said the April 7 incident “was serious and caused damage to the surrounding area,” according to a Bloomberg News account.

Gunji said the purpose of the press conference was to ask the government “to ensure the safety of the aircraft” and take the time to find out what happened.

The union’s account reveals the April 7 incident as one of the four instances of power-panel short circuits cited in January by Boeing Vice President Mike Sinnett in an interview with The Seattle Times. Sinnett didn’t identify the airline at the time, and a company spokesman again declined to do so Wednesday, saying that’s up to the customer.

Sinnett, the 787’s chief project engineer, said that in each of the power-panel incidents electrical arcing inside a circuit board — “a low energy arc that lasted milliseconds, very small” — had damaged the board and shut down some of the plane’s electrical power.

He said the small spark inside the circuit boards produced no safety hazard, only a loss of function that was handled by the plane’s multiple, redundant power systems.

In January, Boeing had not yet found the root cause, but Sinnett said the problems had been traced to a batch of faulty circuit boards inside the power-distribution panels, which are located, like the batteries, inside an electronics bay.

Boeing spokesman Marc Birtel said Wednesday the investigation of the power-panel incidents is still ongoing.

Following the ANA power panel faults, on Dec. 4, another power-panel short circuit occurred on a United flight out of Houston, forcing the pilot to divert to New Orleans.

A few days later, a similar fault occurred on the delivery flight of a Qatar Airways 787 from Everett to Doha.

And later in December, a second United jet was grounded after another power-panel malfunction.

Kazuo Harigai, assistant secretary of the Japanese union federation, told Bloomberg News that “there have been lots of problems with the (787) electrical system.”

Boeing’s Birtel said that because the 787 has more electrical systems than other airplanes, “it stands to reason” that component malfunctions encountered in service have been “mostly electrical in nature.”

“We’ve been working hard on improving component reliability on the 787 to improve its in-service performance,” Birtel added.

He also reiterated remarks by Sinnett in January — speaking immediately after the first 787 battery incident, the fire on a parked jet in Boston — that the 787 has in general proved as reliable in service as the 777.

*
THE LAST SENTENCE IS A REAL JOKE.

 

Not really. Their own production lines are at maximum capacity for years to come, so they have little to benefit, but much to lose when the time comes to certify the A350 as the public and the NTSB will demand the FAA to really do the job it should have done with the 787.

Also, BOEING abandoning the 250-300 pax market would give a huge opening/incentive for a new competitor – probably Chinese – to enter this very lucrative market.

 

Recap of the events this week,

"NTSB report shows Boeing’s battery analysis fell short"

NTSB report shows Boeing’s battery analysis fell short | Business & Technology | The Seattle Times

 

Why... the A350 is not going to have L-ion batts. A-bus announced last week.

 

At first...

 

Correct... never, though, if this doesn't get fixed...