787 fire at Boston Logan

Sure, the underdog in the 70s with a bunch of white tails... But BOEING in 2005 dumping yet to be built "Dreamliners" by 60%?

 

Are Boeing still making 787s whilst this problem is being sorted out or has production been stopped?

 

Full speed ahead. They have so many airplanes parked all over the ramps in Everett. Many of these are early production models awaiting incorporation of fixes to problems found prior to certification.

 

I'm not denying that Boeing has sold 787's for steep discounts.

I am also reiterating that Airbus does the same when they are able to, and I'm not talking about the "underdog" in the 70's.

As I said before, it's an industry wide practice for the sake of market share in lieu of profit, including Airbus in the present day.

You can't tell me there weren't steep discounts given to get the A380 program off the ground.
I am sure there will be "incentives" offered for the A350 sales, as much as Airbus can afford.

With that said, the point is moot and detracts from the subject of this thread.

 

Agreed.


It has been practiced in every industry when there were 2 or more manufacturers or providers of any good or service.


GM was legendary for it.

Ancient fing news.

 

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PUBLIC DOMAIN SOURCE
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Boeing: ‘no fire is possible’ with 787 battery fix | Business & Technology | The Seattle Times
Boeing: ‘no fire is possible’ with 787 battery fix.

By Dominic Gates

Seattle Times aerospace reporter


Two top Boeing executives delivered an unflinching defense of the 787 Dreamliner in a Friday morning press conference in Japan, insisting that no battery fire will be possible on the airplane once the company’s proposed fix is installed.

Boeing Commercial Airplanes CEO Ray Conner and the vice president in charge of 787 systems, Mike Sinnett, outlined the technical details of the solution in the homeland of the plane’s two biggest current operators.

Boeing expects to complete the testing demanded by the Federal Aviation Adminstration (FAA) within weeks, not months, they said.

With most of the testing done in the lab, Boeing plans to fly only a single flight test.

The executives outlined multiple layers of protection designed to prevent battery cells from overheating, culminating in a final protection: a sealed steel enclosure that vents any gases directly out of the airplane.

That box “eliminates the possibility of fire,” said Sinnett.

The first layer of improvements is inside the GS Yuasa plant that manufactures the batteries in Japan. Boeing and GS Yuasa have tightened quality controls and added new tests on the batteries that come off the line.

A series of design changes have been made inside the battery, too.

* These include an electrical insulator wrapped around each of the eight battery cells, to electrically isolate cells from each other and from the battery case, even in the event of one cell’s failure.

* Electrical and thermal insulation installed above, below and between the cells will help keep the heat of the cells from affecting each other.

* Wire sleeving and the wiring inside the battery will be upgraded to be more resistant to heat and chafing and new self-locking fasteners will attach the metallic bars that connect the eight cells of the battery.

* Small holes at the bottom of the battery case that contains the battery cells and the battery management unit will allow moisture to drain away from the battery.

* In addition, Boeing is adjusting the battery charger to narrow the acceptable level of charge for the battery. It will both lower the highest charge allowed and raise the lower level allowed for discharge.

* The final level of protection is the steel box enclosing everything.

Sinnett’s claim that the battery enclosure box prevents fire altogether clearly surprised his skeptical audience of journalists.

Combatively, he insisted that the press has misreported the purpose of Boeing’s battery enclosure box by describing it as “containing a fire.”

No, Sinnett said.

“This enclosure keeps us from ever having a fire to begin with,” he said.

He said that the electrolyte inside the battery — a flammable liquid that releases oxygen if it burns — “does not release sufficient oxygen to materially contribute to combustion.”

The venting system, including a tube from the battery box to the outside of the plane, draws out the air and ensures that there isn’t enough oxygen, he said.

He said Boeing has been testing the box and venting system for six weeks. Heaters were placed on the side of an internal cell to induce a short circuit and then, when the cell vented hot electrolyte, Boeing used ignition devices to try to induce combustion.

“In no case were we able to ignite the electrolyte,” he said.

Boeing then pumped outside oxygen into the battery interior “with the sole intent of trying to create combustion” and even then they were able to induce combustion that lasted only 200 milliseconds before going out.

“We’ve been able to demonstrate that no fire is possible,” Sinnett concluded.

Sinnett also quibbled with the use of the term “thermal runaway” — an uncontrolled battery overheating.

That’s something that occurred in the two events that prompted the grounding of the 787 fleet — the fire aboard a 787 on the ground in Boston and a battery smoldering in flight in Japan — according to both investigating authorities: the National Transportation Safety Board and the Japan Transport Safety Board.

But Sinnett said the term has different uses according to different “perspectives” and that the only one that really matters to Boeing is at the “airplane level.”

At that level, he insisted, thermal runaway did not happen.

He said there was no fire on the Japanese flight. And in the case of the Boston fire, only some small flames were observed outside the box, “where there was oxygen,” but no fire inside the battery.

“In neither event was there a fire inside the blue box of the battery,” Sinnett said.

He reiterated Boeing’s position that the only way to induce thermal runaway at a level that would release enough heat to threaten the airplane would be if the battery overcharged. But after reviewing the entire in-service record of the 787, he said, “we are confident that we have never seen overcharging in the fleet.”

Sinnett said that “we may never get to the single root cause” of the two battery events in service, but that the package of changes covers all possibilities and is the “most robust process we’ve ever followed in improving a part.”

“There are dozens and dozens of examples in the past 40 years where we’ve solved problems without having the root cause,” Sinnett said.

Sinnett said he’s been on test flights of the 787 where his engineers have deliberately disabled three layers of systems protection and the airplane has flown home safely on the fourth redundant layer of protection.

The 787 has “got more ‘get home’ capabilty than any airplane that’s ever been built,” he said.

Conner said airline customers have been totally supportive of Boeing’s fix.

“Everyone feels very comfortable with what we are doing,” Conner said. “I plan to fly on the very first flight.”
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So, in summary,
"We don't don't know the root cause but we’ve been able to demonstrate that no fire is possible".---- FAMOUS LAST WORDS.

 

Okay I assume these batteries have a purpose. What happens to the plane when one battery goes out of action due to fire or anything else?

Pete

 

They pull power from the other battery, or from a generator on either main engine or the Auxiliary Power Unit.
If that fails they can lower the Ram Air Turbine from the wing-to-body fairing and pull power from it, at least to power the electric flight controls and minimal navigation. (Forward flight required)

Lots and lots of redundancy.

 

Everyone but me: I shall wait a few years before booking a flight on a 787.

 

Me too.

And in the case of the Boston fire, only some small flames were observed outside the box, “where there was oxygen,” but no fire inside the battery.

“In neither event was there a fire inside the blue box of the battery,” Sinnett said.

The fire in the box is not as much a concern to me as the fire outside the box damaging the aircraft primary structure, which did occur.

 

NTSB Contradicts Boeing Claim of No Fire in 787 Battery - Bloomberg
Investigators examining the Jan. 7 fire aboard the Dreamliner in Boston haven’t ruled out that flames erupted within the lithium-ion battery container, Peter Knudson said today in response to questions about the issue


A classic example of someone who may have once been an engineer, but no longer deserves the title
"Michael Sinnett, Boeing’s chief project engineer, said in the briefing that investigators hadn’t found evidence of flames within the Boston battery’s container box, an indication it worked as designed to limit damage from a battery failure

Apparently the heat damage to primary composite structure fell within limits.

 

It also helps that Airbus is subsidized by the governments in which the components are made and assembled. Socialism pure and simple.
Unfair competition just as the Chinese govt subsidized solar panels.

 

Really the battery is there to start the Aux power unit that actually uses pneumatic power to start the engines. Electric power for the aircraft comes from the generators on the engines and APU and some have the drop down wind generator.
The battery is a very small contributor to the electrical system.
As I see it the main problem lies in a run away overheat/fire in the electronics compartment. Now that is serious stuff.

In case of an electrical shutdown the battery has enough juice to run a few gauges, drop the flaps, and power the radio for a better location of the crash site

 

I'm not taking sides here, but the WTO ruled the Boeing gets subsidies just the same in the form of major tax breaks in the states it produces aircraft not to mention the proverbial military spends that has insight and tech trickling down.

 

I won't be booking any flights on a 787 either.
I am not buying into the assumptions made in the article whatsoever.

 

PUBLIC DOMAIN SOURCE (GOOGLE)
http://www.boeing.com/commercial/aeromagazine/articles/qtr_4_07/article_02_1.html

On the 787, bleed air is only used for engine cowl ice protection and pressurization of hydraulic reservoirs. The electrified functions are wing deicing protection, engine starting,driving the high-capacity hydraulic pumps, and powering the cabin environmental control system. (So, the batteries do get a good workout)
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True.

 

And the US (State and Fed) gives subsidies for solar panels here... same thing.

Sorry, a bit off topic.

 

I do not believe that is correct. The 787 uses electric start. Furthermore, the RAT apparently only generates enough power to run the center hydraulic system, which uses electric pumps.

If you were to lose both engines and the APU wasn't running, those batteries would be very important indeed!

 

I stand corrected on the 787 starting apparently.
Its been 15 years.

If electrical generation was lost batteries the size of an small automobile would have to be used to run all the systems per Spasso's diagram.
I'm sure (?) there is an emergency buss that kicks out non-critical stuff or else a "normal" battery would overload almost immediately.

Wing de-ice with electric ?
Wholly crap.

 

I believe that is the real reason why they had to have the Li batteries-- it needs a LOT of battery capacity. There is an article on the Boeing website which talks about their "all electric" design philosophy for the 787.

 

LA Times today said Dreamliners will be flying again in 2 or 3 weeks. The have a new box that contains the batteries so that no oxygen can get in them, among other changes.

FAA has already approved the change.

My understanding is that this is one terrific plane. Too bad it got off to this rocky start.

Boeing plans on 787 Dreamliners to be airborne 'within weeks' - latimes.com

 

It's my understanding that they have redesigned the batteries themselves, also.

 

Mebee I got the mfg wrong. Didn't verify the make before posting. You might have it right.
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NiCad can be retrofitted, also could go with simple lead/acid, or gel type. All/any of the changes must go through a Supplemental Type Cert process now that the plane has been certified by the FAA under a standard type certificate. Once the STC is granted for the fleet, it can be rolled into a standard type modification, or sometimes called a 'block' designation.

There are several ways to skin this cat. The greater the change in materials, methods, the harder it is to get a STC approved in short order. Also, NiCads and other batts weigh more, and would affect the weight and balance a bit. Comm planes also go through another barrier to certification having to do with life-cycle, service life, maint interval, etc. I'm not an expert on that stuff by a long shot.

Here is an abstract from the Type Certificate that will be looked at quite carefully:

25-359-SC Lithium Ion Battery Installation.

This is one of the Special Conditions for certification. There is also something called an Equiv Level Of Safety method for doing what we've always done, but with a new twist. In this case, it looks like there is an ELOS by the FAA that is going to get some serious scrutiny:

TC6918SE-T-P-19 §§ 25.1023(b) and 25.1121(c) ELOS Finding for Auxiliary Power
System

There also may be some AWLs, which is an AirWorthiness Limitation which defines the acceptable minimum criteria for the plane. Also, ALI (Airworthiness Limitation Instruction) for the operation of the batts/aux power systems.

Sigh,,,, paperwork never ends with the FAA.

 

I hope this is not a repost: this is BOEING fire box.

I pity the tech who will have to replace those batteries at short notice and unscrew/screw about 44 bolts each time.
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