787 fire at Boston Logan

True at the moment. But Boeing has a very important update to the 777 planned in the next few yrs. They will need to make some corrections throughout their entire organization (management and engineering) to get it done properly. I know they've started making some changes and the knowledge base is there for the 777, provided they stick with proven technology.

 

I agree 100% and it's worrisome because I am not seeing the cultural shift required to prevent the repeated mistakes of the 787 program.

They need to tone down the "Lean Manufacturing" mentality and get back to what made Boeing a great company in the first place, the three major tenants;
* The best design
* The best performance
* The best quality

Sadly, "Continuous Quality Improvement" of days past has taken a back seat to "Lean" and "Share Holder" value. (I am sure the Share Holders are pretty upset at the turn of events).
They got bit in the ass on that one.

Disclaimer: Opinions expressed above are solely my own and in no way reflect the official views of Boeing and it's affiliates.

 

Apparently the battery maker doesn't support Boeing's fix.

UPDATE 2-Boeing, battery maker at odds over 787 fix - WSJ - Yahoo! Finance UK

I quoted snippets, not the whole article.

 

I'm with Yuasa on this.
So far Boeing's fix is addressing the symptoms, not the cause.

 

Boeing has talked about redesigning the batteries themselves (larger cell separation and ceramic spacers between the cells)..

I consider that addressing the cause...


Yuasa may be reluctant to redesign the batteries... probably gratis, possibly an admission of guilt...

 

Actually, I don't even agree that it addresses the symptoms. It's merely a fallback 'containment' system to prevent loss of aircraft in the event of an onboard fire (which I'm skeptical of). It does nothing to address the overheating issue, possible wiring defects of the plane, battery issues, etc.

If I were a national agency, I wouldn't certify this aircraft for flight with this containment box. That's a piss-poor solution. In fact, I wonder why (or how much effort) it is to just swap out the batteries for the other ones (forgot what they are called) and just accept the weight penalty until a proper diagnostic and solution is found. A heavier, yet operating airplane is more profitable than a grounded non-rev generating aircraft.

This whole thing reeks of throwing a bunch of **** ideas to the wall and seeing what sticks.

 

NiCd or LiFePO4?

 

They are NOT just talking about a containment box with vents.

They are also redesigning the battery with bigger spaces between the cells and ceramic insulaters also between the cells.
This has been mentioned in a number of posts above, news releases, etc.

On this thread there was also a good description of changing to, say NiCad batteries. All sorts of wiring and control changes would be necessary.

You should go back and read some of the other informative posts ... gave me a better understanding.

 

They need other cells. Plain simple. You can't have cells that regularly start to burn on a passenger plane.

 

I was told that the cells in these were basically the same as those in a Tesla or Prius.

 

Even if they were exactly the same a Boeing is not a Tesla or a Prius.

 

Nope...same cobalt lithium tech, different design and layout in the Tesla (can't speak for the Prius). If it were he same, Elon Musk wouldn't have been so outspoken against the 787 battery.

 

But it seemed as though Musk was talking mainly about the need for more space between cells.

Which is what I understand Boeing is talking about doing. Plus adding the ceramic spacers. Maybe?

 

+1

Again, that is simply "disaster mitigation", not a solution IMO.

This is the only thing I've read that seems to address the *cause*;

FWIW, I guess I'd add temperature monitoring too. Increasing separation, isolating 'em & venting overboard doesn't fill me with confidence, that's for sure!

Cheers,
Ian

 

The word OVERHEATING means the temperature is outside normal operating parameters.
As long as this is happening the problem is NOT solved regardless of the boxing, venting and insulating.

I have not heard what the CAUSE of the overheat is. Until that is determined the problem is NOT solved.

What is being done to prevent the overheat of any one cell?

So far the efforts are to isolate the cells from one another and to contain the symptom of overheat and fire. This is not a solution.

This B.S about the airline customer having to change out both $16,000 batteries numerous times on an aircraft less than two years old is ridiculous! Where is the savings and economy in that?

Boeing even suggested that the batteries exceeded shelf life in some cases, in less than two years? Really!

The spin doctors are alive and well.

 

PUBLIC DOMAIN SOURCE

Boeing’s Conner says 787 fix can ‘move really fast’ | Business & Technology | The Seattle Times

By Dominic Gates

Seattle Times aerospace reporter

Boeing Commercial Airplanes CEO Ray Conner said Monday the company’s fix for the 787 lithium ion battery problem can be swiftly implemented and the Dreamliners can be flying again soon if the FAA gives Boeing approval to go ahead.

“So much depends on where the FAA goes,” Conner said. “Hopefully they will agree with the certification plan and then we’ll go into testing.”

“Once we get that, this will move really fast in terms of being able to get the airplanes back into the air.”

Just how fast that can happen will depend not only on the FAA’s approval to go forward, but also on how much testing the agency will demand to certify the fix.

Conner gave no indication of how much time he believes will be needed for the certification testing. But he expressed full confidence that Boeing’s fix will cover all potential FAA requirements.

“We’ve come up with a very comprehensive solution to the battery issue,” Conner said at the JP Morgan aviation conference in New York. “We would not go forward unless we felt like we had it nailed.”

Boeing is preparing kits with the parts needed to retrofit the in-service fleet of 50 airplanes that have been grounded around the world for more than six weeks.

“We are prepared. We are ready to go,” Conner said. “It’s a matter of getting the kits in place and off and running.”

After those 50 jets are retrofitted, he said, Boeing will quickly apply the fix to the undelivered airplanes now grounded at Paine Field, and “we’ll be off and into the delivery cycle.”

Conner conceded that this optimistic outlook hangs upon the FAA’s call as to whether the fix is comprehensive enough.

For now Boeing is maintaining its production schedule, he said, and by mid-year will increase the 787 assembly rate from 5 per month now to 7 per month.

“That could change if things go sideways with FAA,” Conner said. “We’ll cross that bridge when we come to it.”

Boeing had been expected to launch the next version of the Dreamliner, the 787-10, in June at the Paris Air Show. It was in the process of offering the stretched 787 to customers when the battery problems emerged last month.

Conner said Monday the grounding of the 787s has stalled some of those customer negotiations, potentially delaying that launch.

“Clearly having the fleet down right now has slowed things down quite a bit,” he said.

However, assuming the battery problem is resolved, he said, the 787-10 launch will likely go ahead more or less as planned.

“Hopefully we’ll be able to bring that forward soon,” he said.

Answering a slew of questions on the lithium ion battery problem, Conner tried to dispel some passenger worries by stressing that these batteries “are not used in flight. They are a backup.”

And he said Boeing’s engineers are “very comfortable” with the lithium ion battery technology, even though rival jetmaker Airbus — chiefly to ensure that its schedule is not affected by any potential new battery-related regulations — has chosen to switch back to traditional nickel-cadmium batteries for its forthcoming A350 airplane.

“Through all the analysis we’ve done, we couldn’t see any reason to switch back,” Conner said. “We’ve got a solution in place that addresses all the potential factors” in causing the battery fires that grounded the plane.

He said a team of about 200 Boeing engineers has worked on the fix, clocking about 200,000 hours of analysis and testing, in consultation with “a very impressive outside team” of top battery experts.

The FAA is expected to give its initial response to Boeing’s proposed fix this week.

 

These batteries according to Monk are difficult to control temperature wise. He designed his batteries because he is aware of this issue with larger spaces between the cells.

If he was able to control the temperature he would not have done this. Therefore if Boeing are going to use these batteries they need to understand their characteristics and they have to be designed with larger space between the cells. You cannot ignore something like this.

Personally I do not think these types of batteries are suitable for an aeroplane. The weight savings do not outweigh the considerable safety issue. The electric car needed this technology but in this case it is worth the risk as you can pull over and jump out of the car if you have to. Not good but it is a valid option.
Pete

 

You mean MUSK?... Monk was a TV show.

Larger spaces between cells IS one of the changes they are doing... plus ceramic insulators between the cells.


Thanks for the above, Spasso...

 

That would make the rather negative assumption that advancing technology cannot eliminate the overheating problems of the Lithium Ion type in the future.

 

Good point, but maybe Boeing have been premature and these batteries are not ready to be classified for some types of operations?
Pete

 

Even if this is approved, doubt it's going to address all the electrical issues various 787s from United to Qatar to JAL to all hell, ALL of the carriers are experiencing.

When the plane is working (as designed) seems carriers are thrilled with it, but when it's down, it's really down. And that seems to be more frequent these days pre-grounding.

 

Sound's a bit like an early Microsoft software.

 

Exactly.

 

...and late.

 

BSOD <> comm aviation.

lol, I keel myself.

I'm an EE but battery tech and charging circuits are not my forte. Having said that, there is a tipping point on internal resistance of a battery where it will simply convert additional charging current into heat, and not the chemical reaction needed to recharge the battery.

This is a design consideration for Li+ type batteries, as I recall they have a typically higher internal resistance than other common Pb or Ni substrates. Again, not an expert in batts. Also, the carbon metal plates are brittle, and if they crack and/or touch, that's gonna set off a serious current crowbar situation. The charging circuit needs to be very tightly controlled with Li+.

I"m not even sure of the failure mode, but this looks a lot like current induced thermal runaway. Whether it was caused by the charging circuit, it was caused by an internal change in resistance, leading to an over-current situation I think might be the crux of the biscuit in remediation.

Things I might do as an EE to remedy:

1. multi point thermal sensing on the batt case, and maybe even in the embedded media of the batts with a closed loop control over charging current and voltage.

2. Phase controlled FET current/voltage regulation that can respond instantly to differing voltage and temp situations.

3. Increased cooling path for batteries. There's no replacement for heat extraction once the heat is being generated. You can make all the plate distances, and phenolic diffusers you want inside the batts, but when the temps start to climb, those BTUs gotta go somewhere.

Again NOT a battery expert!