Boeing 787 news

[sn26567]

787 humor

[jan_olieslagers]

Talking of which: on today's airliners, what are batteries typically used for?
They must certainly serve to start the APU, I should think.
But I seem to understand they _never_ power the various buses - these are AFAIU normally fed from the main engines' alternators, or perhaps from the APU, or at last need from an extra alternator, driven by a wind turbine that is folded out in this dire case?
If this holds true, i.e. batteries are only there for starting the APU, they shouldn't be all that voluminous - I even understand an APU is not standard equipment on all airliners?

[RoMax]

I assume batteries are often used as back-up systems. Especially for an airliner like the 787 that uses so much electricity (including systems that are powered by bleed air on other aircraft). Batteries can pick in faster than the external turbine (to bridge the short time between the failure of the normal generators and the external turbine giving power and possibly to assist certain systems besides those driven by the turbine?). They could be used when a certain system suddenly needs a lot of power that can be better extracted from lithium-ion batteries than from the general system to avoid big, sudden differences in power usage and distribution around the system.
Just some ideas, I don't know either.

[sn26567]

re the Air India flights: I understand they moved the planes to BOM, that's where they carry out major maintenance...

Three of Air India's six Dreamliners were flown from Delhi to its engineering base in Mumbai on Feb. 2, with another two transferred in the days following last month's decision by U.S. regulators to stop 787 flights.

Though its fleet of six is now officially grounded, the carrier has flown five of the planes to Mumbai.

A senior Air India executive confirmed the flights took place, after consultation with Boeing, and said they were also motivated by an effort to avoid high aircraft parking charges in Delhi. Boeing declined to comment on the flights.

[earthman]

I would assume that a plane would also use batteries as a buffer between the power generation part and the power users, just like the battery in a car is used once the engine is running. Although this may not apply to the APU batteries.

[Desert Rat]

Most of the time,the batteries are not connected to the network.

they only connect when you start the APU or when the voltage drop under a certain value, or in case of loss of AC busses, in this case one battery will power an AC bus through an AC static inverter, the other one will power the DC essential Bus.

This is the typical Architecture on modern A/C

[sn26567]

Boeing applies to conduct 787 test flights

Boeing has formally asked the FAA to lift the grounding of the 787 for test flights. If the FAA lifts the grounding, the 787 would only be allowed to fly test flights to investigate the battery problems. Boeing 787 test flights may begin in days and could last weeks. Test aircraft ZA005 or ZA006 are likely to be tapped.

The FAA is likely to grant permission for Boeing to fly the 787 on these test flights as early as this week.

Meanwhile, there is lack of progress in the ground tests of the batteries.

[sn26567]

The ANA Boeing 787 lithium ion battery that failed Jan. 16 exhibits signs of “thermal runaway,” according to Japanese investigators. The Japan Transport Safety Board (JTSB) said that the badly burned ANA 787 battery experienced an “uncontrollable high temperature” associated with thermal runaway. The US National Transportation Safety Board (NTSB) has earlier said the Japan Airlines (JAL) 787 lithium ion battery that sparked a fire in Boston Jan. 7 similarly shows indications of thermal runaway.

The JTSB and NTSB both have not yet been unable to determine a root cause of the lithium ion battery failures.

[quixoticguide]

Tue.05. Feb 2013 | Day 19 of no-flying


http://jacdec.de/info/787Safety/jacdec-787special.htm

[sn26567]

According to Jon Ostrower from the Wall Street Journal, ZA005 is almost certainly going to be leading the airborne 787 battery testing because ZA006 is in change incorporation and refurbishment.

[sn26567]

NTSB is planning a second press conference tomorrow Feb 7 at 11am Eastern, exactly a month after the Boston 787 battery fire.

NTSB Chairwoman Deborah Hersman says she is still "weeks away" from saying "what happened and what needs to be changed."

[sn26567]

The FAA has allowed Boeing to ferry one 787 from Texas to Seattle with a minimal crew.

According to Jon Ostrower from The Wall Street Journal, Boeing has proposed a series of battery changes on the 787 to minimize the risk of fire and get the plane flying again as soon as March. The company is looking at increasing the separation between cells in the lithium-ion batteries to reduce the potential hazards from heat or fire spreading within the batteries and adding enhanced heat-sensors. Boeing also is considering ways to keep cells more rigid, preventing them from shifting under certain conditions and interfering with electronics.

The goal would be a new, safer battery that Boeing could propose for the 50 Dreamliners currently grounded around the world, and on future deliveries.

Any changes would require approval from U.S. and Japanese regulators now investigating two incidents last month in which the batteries burned on 787s owned by Japanese airlines. It is not yet clear whether officials would accept a long-term fix that doesn't address the root cause of those incidents.

[RoMax]

The FAA has allowed Boeing to ferry one 787 from Texas to Seattle with a minimal crew.

That's one of the China Southern aircraft that was painted in Texas. Boeing requested to operate a ferry flight back to Paine Field.
The request to operate test flights is still pending for approval.

About the batteries, it may be approved as an intermediate and relative fast solution. But I'm sure that if they ever found the root cause of the problems, they'll demand a firm solution by Boeing.

[Inquirer]

About the batteries, it may be approved as an intermediate and relative fast solution. But I'm sure that if they ever found the root cause of the problems, they'll demand a firm solution by Boeing.

At least this link doesn't sound very hopeful on getting the 787 back in the air anytime soon.
It very much looks like it could take many weeks, if not months before the ban is lifted!

http://www.bbc.co.uk/news/business-21363491

[RoMax]

Many weeks for sure. Many months, that'll depend on what kind of solution the authorities will approve...

[sn26567]

The FAA has allowed Boeing to ferry one 787 from Texas to Seattle with a minimal crew.

That's one of the China Southern aircraft that was painted in Texas. Boeing requested to operate a ferry flight back to Paine Field.

It can be followed live here: http://fr.flightaware.com/live/flight/BOE382

And from now you can also follow the live feed of the NTSB press conference: http://www.wltx.com/news/article/220525 ... er-Safety-

[sn26567]

Some important statements made by NTSB Chairman Deborah Hersman during the press conference that just took place:

• Based upon findings , we believe that the evidence points to a single cell, as the initiating event of the fire.
• While the entire battery suffered damage, its clear the left side of the battery - Cells 5 thru 8 – experienced the most thermal damage.
• The body of evidence strongly suggests the event initiated in Cell #6. Cell #6 has multiple signs of short circuiting – which resulted in thermal runaway in the cell.
• The thermal runaway cascaded to other cells in the battery, as is evidenced by the damage to those adjacent cells.
• We are working to identify the cause of the short circuiting in Cell #6. We have ruled out mechanical impact damage to the battery. All mechanical damage to the cells and the battery case occurred after the short circuiting in Cell #6.
• We have ruled out EXTERNAL short circuiting of the cells or battery.
• We are still considering several potential causes for the short circuiting in Cell #6. They include: looking at the state of charge of each individual CELL and the method and delivery of that charge.
• We are also looking for evidence of contamination, electrode folds, wrinkles and pinches and the assembly of the cells and battery.
• The 787 battery is a collection of eight individual cells packaged together in one box. We are looking at the total design of the battery.
• Because of the unexpected nature of the battery failure, our investigators began reviewing the certification of the 787 battery design.
• Boeing certification tests “showed no evidence” of cell-to-cell propagation of internal battery problems. The investigation has demonstrated that a short circuit -- in a single cell – can propagate to adjacent cells and result in smoke and fire.
• Boeing certification tests concluded in the probability of only one smoke event for every 10 million flight hours. Now two smoke events happened after only 100,000 flight hours.
• The decision to return the 787 to flight will be made by the FAA.

See slides of the presentation: http://www.ntsb.gov/investigations/2013 ... -7-13.pptx
NTSB press release: viewtopic.php?f=31&t=49690
and full video of the NTSB Chairman's presentation:

[RoMax]

[*]Because of the unexpected nature of the battery failure, our investigators began reviewing the certification of the 787 battery design.
[*]Boeing certification tests “showed no evidence” of cell-to-cell propagation of internal battery problems. The investigation has demonstrated that a short circuit -- in a single cell – can propagate to adjacent cells and result in smoke and fire.
[*]Boeing certification tests concluded in the probability of only one smoke event for every 10 million flight hours. Now two smoke events happened after only 100,000 flight hours.

Not to say you left it out on purpose, but it's important to tell that the NTSB said they will also look at the FAA's part in this story (after all, they are the ones who approved the tests performed by Boeing). It wouldn't be the first time they blame the FAA (after the problems with the DC-10, the FAA was also blamed, I believe they were even fined).
But in this certification, Boeing had a lot of freedom. Yes it was the most extensive test program ever, but the FAA didn't knew how to test all these new technologies (or better: they didn't have the experience to test these new technologies). Because of that they left a lot of the test over to Boeing.

[sn26567]

The FAA has allowed Boeing to ferry one 787 from Texas to Seattle with a minimal crew.

Authority to perform the ferry flight, which was conducted today (Feb 7) under a Special Flight permit, was conditional on the crew performing pre-flight inspections of batteries and cables for signs of damage, a mandatory check for battery status on the electronic display before take-off and continuous monitoring for battery related messages during the flight itself.

The pilots on the 787 ferry flight indicated that the flight was uneventful; the battery status was indeed monitored throughout the flight.

Image of the 787 landing at Payne airfield today: http://www.flickr.com/photos/theboeingc ... 453429969/

[Bralo20]

Because of that they left a lot of the test over to Boeing.

Most of the testing was indeed done by Boeing itself, not only the testing of the batteries and related systems but you can say they self-certified the whole plane for the FAA. The FAA officially conducted oversight but nearly the only thing they did was put stamps and signatures on Boeing's documents and issued a type cerificate for the plane.

While I love Boeing and think that they make the best planes in the world (especially the 747 and the 777 which prefer on longhaul trips) I think they went a bit to far with the 787 and it can (and will probably) come back and bite them in the ass. Besides its looks I was never a big fan of the Dreamliner, from the beginning it smelled trouble... I wonder what we'll see in the next couple of years when the planes have some years of service behind them, honnestly I don't think the battery problem will be the sole problem with the 787.

But I guess we'll have to wait and see