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Old 16th January 2013, 01:35 AM   #1
MikeG
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Boeing 787s grounded by Japan

What's going on with the "Dreamliner"? Grounded in Japan until further notice, a recent fire on board, fuel leaks, cracked cockpit window and some brake problems.......all on a very new product.

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Old 16th January 2013, 03:52 AM   #2
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Seems typical so far. The only item on the list of problems that is a concern for me is the electrical fire. They need to get to the bottom of that quickly. The rest seem like typical maintenance issues.
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Old 16th January 2013, 05:19 AM   #3
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It should be noted that, as far as I know based on a news report this morning, Japan Airlines was the first airline to receive 787s. Any problem still remaining with such a new design would show up first in those planes.
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Old 16th January 2013, 08:59 AM   #4
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FAA also ordered a safety review.

I don't think that a few hiccups is particularly unusual for a new model of airplane.

But I did hear that they outsourced a lot more parts than previously.
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Old 16th January 2013, 09:04 AM   #5
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From the OP link:

Quote:
There have been six separate safety incidents with Japanese-owned 787s in the last week and a half. But they are not all equal.

The incident today was by far the most serious. Smoke inside an aircraft while in-flight is always a serious matter. That's why the plane was so quickly diverted, and probably why ANA and JAL have now ordered their fleets to be grounded.

It also looks like this incident may not be isolated. It appears very similar to an electrical fire on board a Japan Airlines 787 in the United States last week.

The source of that fire was the 787's lithium Ion battery pack. All the way back in 2007, the US Federal Aviation Administration expressed concern about the installation of Lithium Ion batteries on board the 787 because of their known problem with so-called "thermal runaway". It's a problem that has caused mobile phones and laptop computers to catch fire in the past.

The 787 is not the only aircraft to use Lithium Ion battery packs. The Airbus A380 uses a smaller number. And the upcoming Airbus A350 will use a much larger number
If the problem is just a problem with the specific batteries used, it probably is not a fatal flaw. They just have to get better batteries, no?
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Old 16th January 2013, 12:44 PM   #6
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Hmm... Lithium batteries in aircraft are a no brainer due to their capacity vs size/weight performance. But the Dreamliner and AB380 are the first two I have become aware of that use them.

This isnt likley to be any kind of fatal flaw...but it could be quite problematic.
Most other aircraft used to use nicad batteries. But maintaining these batteries was expensive and had high labor cost. Nicad batts also routinely caused aircraft to be grounded for excessive time because doing repairs and capacity checks routinely take 2-3 days. No way around it. Parts and cells were also very very expensive.

For the last 10-15 years sealed lead acid batteries have displaced nicads as the preferred power source. They were much cheaper and if there was an issue operators just replace them since they were 60-90% less in cost than nicads. By just replacing these lower cost batteries they drastically increased departure reliability.

But replacing a nicad with a sealed lead acid was usually a straight forward process. The nicad and its replacement were usually of similar dimensions and electrical capacities. Keep in mind you can not just replace parts on aircraft because they fit. When the aircraft is certified it is done so with each and every chosen component in mind and it is all documented. Any deviation in any way from that type certificate must be accompanied by engineering approval. This includes using a different PN battery or battery type. The procedure for that deviation is known as a "supplemental type certificate" or STC. Once an STC is done it is logged in the aircraft logbooks with pertinent info including updated "weight and balance" info.
Once an STC has been approved by the FAA many times it is approved not just for the one aircraft...but all the aircraft of that particular model. In some cases thousands of aircraft.

Anyways...knowing that and looking at the Dreamliner battery issue....it could be a bit of a problem. Unless Boeing worked with more than one source for these batteries....there is likely only one supplier. Also due to the drastic performance of Lithium batteries...the size of the mount/cradle for these batteries is not likely to correspond to some other off the shelf, readily available battery since other batteries are almost exclusively nicad or sealed lead-acid. Any change from the current design will require engineering and FAA approval. Of course this can be fast tracked but your still probably looking at many days or weeks for the STC to be done followed by more time to outfit each airplane.

The most likely scenario is that Boeing, the FAA and the battery manufacturer are all looking at the failed battery packs at this moment and are coming up with a plan to fix the issue with the current packs. This could be as simple as a tweak in the assembly process. It may also be a tweak on the aircraft such as additional cooling or ventilation. But if the battery has a difficult to spot flaw and this is the only battery approved..it could be a royal PITA for Boeing in the short term.

Also if Boeing hasn't done so already they should be starting the process for alternative sources of this pack or looking into an STC for older more reliable lead acid batteries to be retro-fitted.

Last edited by 383LQ4SS; 16th January 2013 at 12:47 PM.
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Old 16th January 2013, 04:42 PM   #7
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Originally Posted by Puppycow View Post
FAA also ordered a safety review.

I don't think that a few hiccups is particularly unusual for a new model of airplane.

But I did hear that they outsourced a lot more parts than previously.
They've gone to a full grounding now: CNN Story
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Old 16th January 2013, 04:49 PM   #8
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From the CNN story:
Quote:
"Before further flight, operators of U.S.-registered, Boeing 787 aircraft must demonstrate to the Federal Aviation Administration that the batteries are safe and in compliance," the FAA said Wednesday evening.
Looks to me that the battery issue is still not understood. Not good. They will have to demonstrate a reason for the failures along with a fix before the FAA returns them to service.

The rest of those items in the article are normal maintenance items.
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Old 16th January 2013, 08:49 PM   #9
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Some more on Lithium Ion battery fires:

Battery fires: keeping the Li-ion caged

Quote:
A thermal runaway means that the battery cell releases stored energy rapidly, and lithium-ion batteries with higher energy density can release a lot more energy more quickly than other battery types. Lithium-ion batteries contain a highly flammable electrolyte, so they store both electrical energy from the normal battery chemistry and chemical energy from the lithium-based electrolyte.

Thermal runaway can occur when the battery self-heats, which can happen when electrolyte reaches temperatures as low as 158 to 194 degrees F (70 to 90 degrees C), according to the FPRF report. Runaway accelerates quickly at higher temperatures, and the greater the charge in the battery, the faster runaway happens. Temperatures during a runaway can reach 1,110 degrees F (600 degrees C). The battery cells will also experience increased pressure, venting or popping of the cell, possible ignition of cell gases, possible ejection of cell contents and propagation to adjacent cells.
Perhaps a temperature sensor should be installed with the battery and automatically cut it off if the temperature exceeds a safe threshold? And Are these batteries necessary for flying or do they just power the entertainment systems and such? I seem to recall that some laptop computers and other electronic gadgets have had similar problems with batteries catching fire in the past, but that these problems were fixed. Although rare, the chance of it happening is non-zero, so there should be an automatic way to put out the fire and/or keep the battery cool I think.
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Old 16th January 2013, 09:46 PM   #10
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typical compliment of batteries on a medium or large jet are main ship batteries and
various standby batteries. These are used to power various emergency systems such as standby gyro and nav, emergency lights etc in the event of a complete electrical failure.

Emergency lights are for the passenger egress. The standby equipment is for safe operation for a period of time with complete electrical failure.

I am not familiar with the Dreamliner and large fly by wire aircraft. It may have larger batteries beside main ship batteries to power electrical portion of control systems for the fly by wire as well.

When the aircraft is in flight...these batteries are always being charged and all other systems power is supplied by engine drive AC and/or DC generators. The batteries are only there for reserve power during emergencies.

Last edited by 383LQ4SS; 16th January 2013 at 09:48 PM.
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Old 16th January 2013, 09:55 PM   #11
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Originally Posted by Puppycow View Post

Perhaps a temperature sensor should be installed with the battery and automatically cut it off if the temperature exceeds a safe threshold? .
If main batteries overheat there are usually battery disconnects that can be engaged.
For smaller standby batteries many times there are circuit breakers that can be pulled. But they are not always accessible by crew.
The dreamliner though has the newer systems that have virtual circuit breakers. They are now remote controlled through a central computer.

Problem is when you actually have a true thermal runaway...you can isolate the battery completely and it will still cook its self. Very rare...but it happens.
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Old 16th January 2013, 10:36 PM   #12
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Fancy that I remember discussion about the airbus at the time and the small problem it had and people telling its was a crap airplane. Not necessarly here. But i smirk that now the comment section of US based site are all "it is normal" reassuring tone whereas it was with Airbus "a flying coffin" .

Basically in both case there are growing pain and the first few years of life of an airplane are rife with small or sometimes big problem. They usually are sorted out relatively rapidely. I am still a bit surprised at the grounding action, I can't remember a fleet being grounded in recent time, even after the suspicion on airbus pitote... Phased replacement during maintenance yes but not downright grounding. Bad memory on my side maybe ?
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Old 16th January 2013, 10:46 PM   #13
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Sigh. My first reaction to this round of bad news was, "The name is still Boeing, but the quality is MacDac. When Boeing 'merged' with MacDonald-Douglas, the senior MacDac brass took over the Board and the executive suite of the merged entity. Boeing had a reputation for high quality aircraft; apparently, that wasn't profitable enough for the new company.

My husband commented that the battery problem not be a problem with the batteries per se, but rather that the charging mechanism is not working correctly. So right now they're probably trying to reproduce the problem and testing both further batteries and their settings in the planes to determine where the trouble is coming from. And, as another poster already noted, Boeing out-sourced a lot of work that used to be done in-house on this plane.

There is a lesson here.
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Old 17th January 2013, 08:54 PM   #14
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FAA Relied on Boeing-Generated Battery Data

Quote:
In approving Boeing Co.'s BA +1.24% 787 Deamliner to start carrying passengers in 2011, the Federal Aviation Administration relied extensively on data generated by Boeing that indicated the plane's advanced lithium-ion battery systems—never used before on a big jetliner—featured redundant safeguards that were essentially foolproof.
"redundant safeguards that were essentially foolproof"

Quote:
The FAA and Boeing spent years developing special protections in case the batteries, their chargers or associated wiring went haywire. The mandated safeguards included hardware and software able to automatically disconnect batteries from the onboard electrical grid in case of unexpected problems; and additional protections to prevent overheating or overcharging even if the automatic-disconnect system failed.

In hindsight, Mr. Francis said in an interview, senior FAA officials should have decided " 'there's a lot we don't know yet about this technology,' " and "they should have done something differently."

Through a spokesman, Marion Blakey, who ran the FAA while nearly all of the battery-certification work was done, declined to comment. She is now chief executive of the Aerospace Industries Association, a trade and lobbying organization.
In Japan I think they would call this "Amakudari".
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Old 17th January 2013, 10:58 PM   #15
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Praised but Fire-Prone, Battery Fails Test in 787

Quote:
Still, safeguards for lithium-ion batteries have progressed to the point that a fire on an airplane should never have happened, said Sanjeev Mukerjee, a chemistry professor at Northeastern University and an expert on batteries.

“If a battery of that size catches fire, then a whole bunch of mechanisms didn’t work,” Mr. Mukerjee said. “Whoever is making that battery is doing a really bad job.”
If that's the case, then just do a better job of making the batteries, no?
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Old 17th January 2013, 11:08 PM   #16
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Sure seems that way. I was reading about Litium ion batteries the other day. They apparently have several fail safe mechanisms built into each cell. And that apparently goes for all type from cordless drill to phone batteries. Sure seems like a supplier problem. Funny thing is apparently the manufacturer of these particular units is a Japanese company. I also saw a picture of the battery pack in question. It was a complete melt down.
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Old 18th January 2013, 05:32 AM   #17
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Originally Posted by Puppycow View Post
Some more on Lithium Ion battery fires:

Battery fires: keeping the Li-ion caged



Perhaps a temperature sensor should be installed with the battery and automatically cut it off if the temperature exceeds a safe threshold? And Are these batteries necessary for flying or do they just power the entertainment systems and such? I seem to recall that some laptop computers and other electronic gadgets have had similar problems with batteries catching fire in the past, but that these problems were fixed. Although rare, the chance of it happening is non-zero, so there should be an automatic way to put out the fire and/or keep the battery cool I think.
They have a temperature sensor, that was why the pilot made an emergency landing in Japan, he was seeing temperature alerts.
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Old 18th January 2013, 05:35 AM   #18
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Originally Posted by Miss_Kitt View Post
Sigh. My first reaction to this round of bad news was, "The name is still Boeing, but the quality is MacDac. When Boeing 'merged' with MacDonald-Douglas, the senior MacDac brass took over the Board and the executive suite of the merged entity. Boeing had a reputation for high quality aircraft; apparently, that wasn't profitable enough for the new company.

My husband commented that the battery problem not be a problem with the batteries per se, but rather that the charging mechanism is not working correctly. So right now they're probably trying to reproduce the problem and testing both further batteries and their settings in the planes to determine where the trouble is coming from. And, as another poster already noted, Boeing out-sourced a lot of work that used to be done in-house on this plane.

There is a lesson here.
It's not the only problem. Being Lithium batteries, you have to build a failsafe backup system that protects against thermal runaway. This failed, flammable brown liquid came out of the battery when it over heated, even though it never became so hot that it caught fire like the first one.
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Old 18th January 2013, 07:28 AM   #19
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Originally Posted by 383LQ4SS View Post
Sure seems that way. I was reading about Litium ion batteries the other day. They apparently have several fail safe mechanisms built into each cell. And that apparently goes for all type from cordless drill to phone batteries. Sure seems like a supplier problem. Funny thing is apparently the manufacturer of these particular units is a Japanese company. I also saw a picture of the battery pack in question. It was a complete melt down.
Oh, my. Well, that's no guarantee of superior quality.

Wasn't it Sony or some other Japanese company that had an issue with lithium batteries for notebook computers catching fire a couple years ago?

Sony has really gone downhill since the good old days. Their bonds are considered junk bonds these days.
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Old 18th January 2013, 08:15 AM   #20
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Originally Posted by Puppycow View Post
Praised but Fire-Prone, Battery Fails Test in 787



If that's the case, then just do a better job of making the batteries, no?
The batteries are also outsourced-to Japan.
"Made In Japan" is rapidly re-becoming the joke it was in the 1950's and 60's...
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Old 18th January 2013, 08:26 AM   #21
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Originally Posted by Puppycow View Post
Oh, my. Well, that's no guarantee of superior quality.

Wasn't it Sony or some other Japanese company that had an issue with lithium batteries for notebook computers catching fire a couple years ago?

Sony has really gone downhill since the good old days. Their bonds are considered junk bonds these days.
Here is a PC world arctical from 2006 about the dell laptop recall, it lists models affected and claims Sony made the batteries.

http://www.pcworld.com/article/126735/article.html

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Old 18th January 2013, 08:46 AM   #22
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Quote:
executive suite of the merged entity. Boeing had a reputation for high quality aircraft; apparently, that wasn't profitable enough for the new company.
That's interesting as one of the top guys, Alan Mulally , moved to Ford and has done wonders there.

Quote:
ALG reports both Ford and Hyundai have seen substantial jumps in their respective perceived quality, with the Blue Oval enjoying a 37 per cent jump since 2008
That said - I think these are just teething pains from a very new design - I'd fly on one in a heart beat.

Last edited by macdoc; 18th January 2013 at 08:48 AM.
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Old 18th January 2013, 09:03 AM   #23
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Japanese company makes faulty batteries that ground US-made planes sold to Japanese airlines? Wow.
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Old 18th January 2013, 10:15 AM   #24
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Originally Posted by macdoc View Post
...
That said - I think these are just teething pains from a very new design - I'd fly on one in a heart beat.
Which did not happen with the 777. They built a full prototype in a building to check all the wiring in place, but more easily replace in the Systems Integratoin Lab. It even had a full flight deck, etc. A paper about here.

They refused to do that for the 787, and just did the testing using the van that checks it out after it is built before first flights.
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Old 18th January 2013, 10:18 AM   #25
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Originally Posted by Puppycow View Post
If that's the case, then just do a better job of making the batteries, no?
You need to do a better job of making the batteries, and you need a better way of burning in the units before you install them. Nobody cares if 1% of your batteries fail during their month in the "airplane-mockup vibration/pressure/temperature/charge-cycling test stand".
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Old 19th January 2013, 12:35 AM   #26
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Originally Posted by ben m View Post
You need to do a better job of making the batteries, and you need a better way of burning in the units before you install them. Nobody cares if 1% of your batteries fail during their month in the "airplane-mockup vibration/pressure/temperature/charge-cycling test stand".

Good point. The battery packs are "life limited" components. Typically battery pack cells or the entire battery pack must be changed out every 2 years give or take. There is also usually a recuring "cap check" inspection at various intervals. In many cases that is every 6 months. These Lithium batteries may have lengthier life limits and mid point inspections...I dont know. But the safety factor can actually be addressed in two distinct ways.

1) find out what led to the failure and fix it
2) rearrange inspection intervals so failures may be detected sooner.

Sometimes when a defect is uncovered option 2 is the only recourse in the short term. I have seen many instances where a major defect was uncovered and because there was no immediate fix, inspection intervals were severely shortened and the aircraft put back in to service with a new inspection interval. In some case aircraft operated this way for years.

If the Lithium battery inspection interval for capacity check is currently 1 year....the parties involved could shorten that interval to say...every 30 days and potentially feel confidant about returning the aircraft to service. Of course that depends on the circumstances and nature of the failures.

Cap checks on packs like that take quite a bit of time...usually 2 days minimum. So operators have "rotables" or spare components that are on the shelf, fully inspected, and ready to go. This way the downtime is kept to a minimum by swapping out entire battery packs.

The cap check of the removed battery pack involves charging for usually 24 hours. Doing a capacity check at rated amp hour (ah) and then fully recharging for another 12-24 hours. This usually exposes any weakness or issues with the packs and really puts them through their paces.

I am sure this is an option they are looking at currently. I am willing to bet every battery machine available has these packs hooked up doing cap checks to see if a dividing line can be identified between good packs and bad packs. They will be looking at lot numbers/manufacture dates etc to see if there are any patterns.

Funny thing is...sometimes issues like this are traced to one or two guys at a facility who read the tech data/assembly instructions wrong...lol.

I am betting the initial fix will be to cap check and inspect every pack in every aircraft and all spares/rotables. When that is done the data gained will guide a new inspection interval in the short term that is likely to be drastically reduced to 7-30 days.

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Old 19th January 2013, 02:49 AM   #27
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Originally Posted by 383LQ4SS View Post
When the aircraft is in flight...these batteries are always being charged and all other systems power is supplied by engine drive AC and/or DC generators. The batteries are only there for reserve power during emergencies.
As I understand it, that is not true and is the main problem. Boeing, in order to increase fuel economy, designed the plane so that it does NOT draw power from the engines. Thus, battery problems are a fBIG deal.
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Old 19th January 2013, 03:51 AM   #28
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Didn't happen with the 777??

seems Boeings Chief engineer disagrees with you

Quote:
Mike Sinnett, Boeing’s chief engineer for 787, said the Dreamliner’s "teething pains" were similar to those of the 777 model during its first year in service, CBC News reported.
http://www.globalpost.com/dispatch/n...despite-mishap

but what does he know?
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Old 19th January 2013, 03:58 AM   #29
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Does not draw power from the engines/??

Pray tell how do the batteries get charged then???

I suspect this is what you are referring to in terms of savings.

Quote:
The attraction of lithium batteries is that they are significantly lighter than other types of batteries. That saves fuel, which is airlines’ leading expense. They also charge faster and contain more energy. And they can be molded to fit into odd space on airplanes, which most other batteries cannot.

Read more: http://business.time.com/2013/01/18/...#ixzz2IPyKpa95
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Old 19th January 2013, 04:27 AM   #30
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Originally Posted by carlitos View Post
Japanese company makes faulty batteries that ground US-made planes sold to Japanese airlines? Wow.
Don't know if it's the batteries yet, though it could be. The problem could also be the electrical system.
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Old 19th January 2013, 04:35 AM   #31
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Originally Posted by macdoc View Post
Didn't happen with the 777??

seems Boeings Chief engineer disagrees with you



http://www.globalpost.com/dispatch/n...despite-mishap

but what does he know?
Well, he did say that before the grounding. The grounding means that the 787 now has an officially worse entry than the 777.
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Old 19th January 2013, 08:38 AM   #32
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Originally Posted by SezMe View Post
As I understand it, that is not true and is the main problem. Boeing, in order to increase fuel economy, designed the plane so that it does NOT draw power from the engines. Thus, battery problems are a fBIG deal.
Not saying you are wrong. But you would have to show me something for me to believe that. These airplane operate for hours on end throughout the work day. I dont see how any significant advantage could be gained by charging a small battery pack during overnight checks just so it can power some small system throughout the day to unload 1/5000 of the aircraft's electrical load. That makes no sense.

And if you are saying these are huge batteries that power all systems....I am sure that is not the case. Banks of huge batteries to run systems will have a negative impact in the form of excess weight and space. Not sure if you realize the power requirements of a modern aircraft...but they are HUGE.

Anyways...there may be some new design on the Dreamliner I am not aware of that has these batteries operating in flight. But in my 25 years of working on aircraft...I have not encountered it yet.

Last edited by 383LQ4SS; 19th January 2013 at 08:40 AM.
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Old 19th January 2013, 09:46 AM   #33
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Originally Posted by macdoc View Post
Does not draw power from the engines/??

Pray tell how do the batteries get charged then???
Indeed. One leading suspicion is the failure occurred during an overcharge.

http://www.kansas.com/2013/01/19/264...batteries.html
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Old 19th January 2013, 11:11 AM   #34
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Originally Posted by a_unique_person View Post
Well, he did say that before the grounding. The grounding means that the 787 now has an officially worse entry than the 777.
My thought exactly. There is a difference between a few squawks and a fire resulting in grounding.

I found this blog to have some interesting thoughts on it:
http://leehamnews.wordpress.com/2013...ve-on-the-787/
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Old 19th January 2013, 11:30 AM   #35
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Originally Posted by SezMe View Post
As I understand it, that is not true and is the main problem. Boeing, in order to increase fuel economy, designed the plane so that it does NOT draw power from the engines. Thus, battery problems are a fBIG deal.
Originally Posted by macdoc View Post
Does not draw power from the engines/??

Pray tell how do the batteries get charged then???

I suspect this is what you are referring to in terms of savings.
Originally Posted by 383LQ4SS View Post
Not saying you are wrong. But you would have to show me something for me to believe that. These airplane operate for hours on end throughout the work day. I dont see how any significant advantage could be gained by charging a small battery pack during overnight checks just so it can power some small system throughout the day to unload 1/5000 of the aircraft's electrical load. That makes no sense.

And if you are saying these are huge batteries that power all systems....I am sure that is not the case. Banks of huge batteries to run systems will have a negative impact in the form of excess weight and space. Not sure if you realize the power requirements of a modern aircraft...but they are HUGE.

Anyways...there may be some new design on the Dreamliner I am not aware of that has these batteries operating in flight. But in my 25 years of working on aircraft...I have not encountered it yet.
Okay, here's the deal on not drawing power. The engines are bleedless, save for handling bleeds, they do not take customer air for anything. There are two big starter generators on the gearbox and everything required for the aircraft is powered electrically. ie electric hydraulic pumps, electric pressurization compressors, wing anti/de-ice.
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Old 19th January 2013, 12:29 PM   #36
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Yes, Fitter is more correct than I. I reread the article I used as a source and it was either not clear or I did not read for comprehension.

The 787 is different because it does not use bleed air but rather uses the engines to generate electricity directly. See here.
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Old 19th January 2013, 12:34 PM   #37
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here is a good reference covering the bleedless engines. Very different!
http://www.boeing.com/commercial/aer...7_article2.pdf

Its also has a very rudimentary schematic

Here is a pic of the actual battery. It is labeled APU battery.

http://www.guardian.co.uk/business/2...liner-grounded

Either way...these batteries are typically in charge mode when APU/engines are running or really at any time you aren't starting something. Back up and emergency batteries are typically charging during normal operation..which is 99.999 percent of the time.

So it sounds like it now may be a suspected charging circuit. It could also be both parties saying the other is at fault...lol.
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Old 19th January 2013, 01:33 PM   #38
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Originally Posted by 383LQ4SS View Post
Funny thing is...sometimes issues like this are traced to one or two guys at a facility who read the tech data/assembly instructions wrong...lol.
Yep. It's sort of terrifying how easily this can happen.

That's why, if you're procuring mission-critical parts, it feels like you ask for $100 worth of materials-traking, certifications, inspections, inspector-certifications, and similar paperwork for every $1 worth of hardware. And it's not overkill, because any slightly more "casual" procurement has a million ways to go slightly wrong.
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Old 19th January 2013, 02:20 PM   #39
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Boeing 787s grounded by Japan

Originally Posted by 383LQ4SS View Post
here is a good reference covering the bleedless engines. Very different!
http://www.boeing.com/commercial/aer...7_article2.pdf

Its also has a very rudimentary schematic.
My bad, it seems it does have an hydraulic pump, should be two I'd think, on the engine. In my defence in development world we only run with hyds when the test calls for them specifically and I only ran one Trent 1000 during training. My apologies for if I misled anyone.
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Old 19th January 2013, 03:15 PM   #40
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Interesting article on the FAA's review. http://www.aviationweek.com/Article....p25-537815.xml
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