Boeing, battery maker disagree on Dreaminer 787 fix
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Boeing has long blamed its Dreamliner woes on its foreign risk and reward sharing partners. Now it can blame a Japanese battery maker for blowing a whistle on its PR spin about a battery fire fix.
Cause or casualty? NTSB photo of burned 787 Lithium-ion battery
No sooner were there positive signs of a wide ranging solution to the Dreamliner 787 battery problem than the maker of the battery, GS Yuasa Corp of Japan went public with its differences with Boeing as to what precautions should be included in the ‘fix’.
The disagreement is disturbing in its detail, with the Wall Street Journal reporting that Yuasa told the FAA agency that its laboratory tests indicated a power surge outside the battery, or other external problem, started the failures on two batteries.
However Boeing spokesman Marc Birtel said that the investigation has not showed that overcharging was a factor and that the 787 had quadruple-redundant protection against overcharging in any case.
This puts Yuasa and Boeing at odds over what exactly was going on inside the electrical systems and the large lithium-ion batteries that failed in different locations in an ANA and a JAL 787 in January, causing the grounding of all Dreamliners.
At the outset, technicalities aside, such disunity over detail but not purpose between Yuasa and Boeing is death to public if not regulatory confidence in such a high profile matter of airliner safety.
There must be some furious efforts going on at this time to reconcile the different positions and get on with solving two critical battery failures that Boeing always insisted were an impossibility in the Dreamliner design even for several days after the physical evidence was presented of a fire burning inside the JAL battery for at least 99 minutes while a Boston airport firefighting unit fought to bring it under control.
Who do we trust? Boeing, or Yuasa? It’s an alarming question to have to ask.
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It’s truly shocking.
Yuasa battery corporation studied Boeing’s redesigned solution, and said it should contain a voltage regulator.
But Boeing has already started manufacturing its redesigned battery “fix”, and doesn’t want to redesign it again. Retrofitting a voltage regulator would take more time.
Yuasa Corp knows batteries, and I can’t see any possible motive for the company to request this design change, other than if it truly believed that the lack of a voltage regulator could cause the Dreamliner’s Lithium Ion cells to erupt in another uncontrollable thermal runaway.
I guess Boeing must have a lot of faith in its fire containment dome.
Comet if true that there is no voltage regulator on the rechargeable battery circuit then we should never venture foot on a Boeing Aircraft. I mean even the most basic lead acid battery can explode if no regulator is fitted.
The exact words of the Wall Street Journal are:
That may mean there’s already some form of voltage regulator aboard the 787, but Yuasa wants something more sophisticated.
They must be good to conduct lab tests that gives information on the charge history of a battery that has all but been destroyed by fire. I’m no electronics engineer but my bet would be on Boeing having more information from the flight data recorder than Yuasa’s examination of what was left.
Overthetop – Yuasa have been in the battery game a long time and are part of Exide. As an engineer myself, I would tend to listen more to the battery experts rather than just the integrators which is what Boeing is nowadays.
The 787 battery saga will in the future be a textbook example of what happens when you outsource all your engineering to third parties – you lose the full integrated testing that finds all the nasties. I’m sure the charger works perfectly; the batteries work perfectly – but sometimes in the real world the combination doesn’t.
The New York Times uses slightly different wording:
No mention of Securaplane/Thales in the regulating/recharging circuitry mix?
787 not going anywhere in a hurry, JAL has extended Boeing 787 Cancellation until 31 May 2013.
Since 787-8-ZA002 had the inflight fire in test, the electrical system itself has been under scrutiny for ‘distribution’ issues. The power panels (P100), were of poor quality, and subject to “malfunction”.
Then United had inflight failure, with a gen loss, and failure of the system to compensate. Now two more incidents, both with combusted Batteries, though ANA discovered the APU BATT had been wired to the MAIN BATT BUSS, erroneously.
I do not think BOEING is underthinking the Battery issue, instead they are proposing a solution that addresses only the more visible evidences of failure; smoke, and fire. It could be that BOEING know the Batteries are not the source of the problem, but feel that “fixing” this portion of what may be a more systemic issue, will get the fleet airborne one again.
YUASA may well be correct; without regulated voltage into the Batteries, their utility and service life is questionable. To what purpose the FRP of 150 batteries prior? Are we to guess that the “modified cockpit checklists” address this issue?
Isn’t safety a public issue, and not “Proprietary”?
“(2) Design of the lithium ion batteries must preclude the occurrence of self- sustaining, uncontrolled increases in temperature or pressure.”
From the Federal Register, FAA, Special conditions for the installation of Lithium Ion Batteries in this aircraft.
Without a redesign of the Yuasa 65, this condition is not met. Preparing a containment structure for the reults of the failure to meet this federal law seems a bit eccentric…The new and more robust box will be vented to the exterior. At 41000 feet, and a pressure altitude of 6000 in the Battery compartment, this is not easy. Release the pressure too quickly, the remaining cells rupture, and eject themselves through the vent. Not quickly enough, and the pressure builds inside the box. The penetrations in the case for cabling will be certified to what pressure differential?
To retain the Battery, as designed, requires the establishment of the cause of the Battery’s destruction by fire, designing a new battery resistant to self combustion, and proving its utility, performance, and reliability to satisfy the regulator, and the condition…In the regs, it is stated repeatedly that fire is not allowed. Preparing for a fire is not in conflict with the regulation?
Ready by June?
Let me quote from the Seattle Times, 3 February, 2013:
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