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Wednesday, May 29, 2013

Boeing Completes Plug And Play on Its 787 Battery

The  battery debacle is now in the rearview mirror for the Boeing 787.  This milestone of regroup and deploy is over for the customer aircraft already parked around the world. Mission accomplished on time and maybe a little ahead of the first schedule announced earlier this year.  When predictions of how long it will take is asked by all at the press conference held earlier this year, Boeing confidently expressed its sentiments on the issue without know if anymore mishaps would occur.

Here is the scorecard posted by Komo News:

Boeing: All 787s now retrofitted with new battery systems


"SEATTLE - The Boeing Co. has now finished installing the new 787 battery system in all 50 of the delivered airplanes that required a retrofit, company officials said.

Randy Tinseth, vice president, marketing for Boeing Commercial Airplanes, said six of the eight airlines with 787s in their fleets have now returned the jetliners to passenger service. The others are expected to follow in a matter of a few days."

Full Press Points From Komo:

  • Ethiopian Airlines was the first to return its 787 aircraft to the skies. Air India and Qatar Airways restarted flights soon after.

  • United Airlines, the only U.S. company with the 787 in its fleet, put its planes back in air on May 20. The airline, based in Chicago, said it will use 787s on shorter domestic flights before resuming international flying June 10 with new Denver-to-Tokyo service as well as temporary Houston-to-London flights. It's adding flights to Tokyo, Shanghai, and Lagos, Nigeria, in August.

  • Poland's LOT Airlines plans to return its 787s back into service on Saturday.

  • Smoldering batteries on two 787s owned by Japan-based airlines prompted authorities to ground the planes in January. The failure of Boeing's newest, flashiest and most important plane embarrassed the company and its customers.

  • The two battery incidents in January included an emergency landing of one plane, and a fire on another. Federal authorities lifted the grounding order on April 19 but it has taken Boeing and the airlines a few more weeks to fix most of them.

  • The incidents never caused any serious injuries. But the January grounding embarrassed Boeing and disrupted schedules at the eight airlines that were flying the planes. The company had delivered 50 of the planes worldwide.

  • The 787 uses more electricity than any other jet. And it makes more use of lithium-ion batteries than other jets to provide power for things like flight controls and a backup generator when its engines are shut down. Each 787 has two of the batteries.

  • Boeing Co. never did figure out the root cause of the battery incidents. Instead, it redesigned the battery and its charger. The idea was to eliminate all of the possible causes, 787 chief engineer Mike Sinnett said.

  • The changes include more heat insulation between each cell and charging the battery to a lower maximum voltage.
  • Boeing never stopped making 787s, but deliveries were halted. They resumed in mid-May, and Boeing has since delivered two planes, both with the new battery system.
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The view from the rear view mirror has Boeing issuing directives for its battery and electrical systems suppliers to work on root cause solutions. By identify actual data that prove a source for thermal runaway. If lowering electrical spike tolerances from its generator through having limiting controls with its electrical flow to the battery, then Boeing may have indirectly found a contributing cause if no instances of thermal runaway shows on the battery.  This type of spiking may damage vulnerable cells from its battery maker. A vulnerable cell may have some weakness created during manufacturing which would leave it open to surges and shorting in the the cell.  Over time the battery degrades with a constant  electrical workload with a less capable battery, which will accelerate the battery's lack of functionality in an ever increasing failure rate, until it reaches the thermal runaway point. To put it simply, the battery is "now" protected by a narrower voltage range, so no electrical surge will short circuit cell structures. Which surging and shorting leads to an ever increasing weaken battery and then eventually thermal runaway.  

The manufacturer must redouble its effort in quality control to give assurances on Battery cell structure promising that it does not have working vulnerabilities in its battery, which could lead to causal failures through in-cell electrical shorts under extreme loads. Those shorts Takes it further below the battery's ability to receive inputs from the generator and continue its distribution of battery power to its systems while on the ground. 

Boeing has position itself by doing what it can control regarding the Lithium-ion battery from the back end of this technology progression. Through a role of: Boeing is basically the Fire Marshal, for this enterprise. It doesn't hold solutions over root cause, but it can assure its customers they get home safely. Hence, the stainless steel fire box, expunging of toxic fumes, and denial of oxygen to any potential fire or heat source. They can fly this aircraft anywhere in the world without the battery that falls into distress and failure. The FAA knows this, that is why they let it back in the air without documenting the Root Cause, or not issuing a particular fix to that unknown cause.  However, Boeing and partners have narrowed it down to several ways a battery has thermal runaway (fails). Resulting with heat, fire, and smoke, during operations on the ground or in the air.  They have put the battery in a safe place for its passengers, no matter what an incident cause could be! 

Will thermal runaway ever occur again?  That is the multi billion dollar question. Boeing believes they have addressed all contingent possibilities of any Battery root cause failures, even to the point of a total failure battery during flight. They can safely fly and land this aircraft during any battery event. Just as if it were sound and normal for its passengers. No one will come running out of the cockpit to check systems and problems, but the captain will  remain calm and in control while shifting to secondary systems seamlessly.  I really believe that thermal runaway will not occur on the 787 again. I also believe since they have evidence of what a failure looks likes, they will be able to isolate what the real root cause is, and make the advanced batteries and electrical solutions. Then it will put this issue into the history books. In the meantime, a thermal runaway will only occur in the future, if a new conditions unknown to anyone arises. That condition would be different than the possibilities that were recently identified, and addressed on this recent battery and systems modifications.

The Boeing 787 is a Joy to fly, fly-on and fly over your community.

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