FAA Grounds 787s
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From: very close to STN!!
"You don't need these batteries to fly"
Flightglobal:
"norwegian's chief executive Bjorne Kjos, "most people think you need a battery but you don't actually need these batteries to fly....you don't actually need them to fly."
So, just take them out!
"norwegian's chief executive Bjorne Kjos, "most people think you need a battery but you don't actually need these batteries to fly....you don't actually need them to fly."
So, just take them out!
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From: PLanet Earth
Personal experiments with Lithium Batteries of different types.
Trying how much you can squeeze out of them will lead you to increase voltage.
Charging them to an increased voltage additionally increases stored (and usable) capacity in these cells tremendously. Stored energy product increses massively. Up to the point were they blow up.
Emptying them (especially under high load) below a certain threshold will also damage chemistry. The consequences of this will become obvious when charging the next time.
Therefore balancers plus cut-off with monitoring of each individual cell are important for charging in case a cell is defective. Plus ideally continuous monitoring of voltage during discharging in order to prevent damage to cells. They have an operating window with a lower and an upper limit. Outside that window cells are damaged. That said self ignition will only occur above a certain level of energy in the cell.
Trying how much you can squeeze out of them will lead you to increase voltage.
Charging them to an increased voltage additionally increases stored (and usable) capacity in these cells tremendously. Stored energy product increses massively. Up to the point were they blow up.
Emptying them (especially under high load) below a certain threshold will also damage chemistry. The consequences of this will become obvious when charging the next time.
Therefore balancers plus cut-off with monitoring of each individual cell are important for charging in case a cell is defective. Plus ideally continuous monitoring of voltage during discharging in order to prevent damage to cells. They have an operating window with a lower and an upper limit. Outside that window cells are damaged. That said self ignition will only occur above a certain level of energy in the cell.
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"You don't need these batteries to fly"
Flightglobal:
"norwegian's chief executive Bjorne Kjos, "most people think you need a battery but you don't actually need these batteries to fly....you don't actually need them to fly."
So, just take them out!
Flightglobal:
"norwegian's chief executive Bjorne Kjos, "most people think you need a battery but you don't actually need these batteries to fly....you don't actually need them to fly."
So, just take them out!
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From: UK
In the late 1960s my dad had an Airspeed Consul which he flew the family around in, as a PPL. He very often had to radio for a trolley-acc to get started. When I was about five, sitting in the right hand seat, I asked him what'd happen if the engines stopped in the air (i.e. no trolley-acc, no flies on a five-year-old) and he just said 'it won't'. We once lost battery (radio + ADF) VMC on top and he asked me (at age five) to change the batteries over (only he and I were on board and no AP). I don't think I managed that, but am still here
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From: Albuquerque USA
other Li-Ion in modern transport aircraft
Originally Posted by Spooky 2
In addition to the batteries in question there are two other batteries for standby power of the flight controls. No one seems to question these?
A380 special condition Federal Register entry
Also, the widely publicized A350 retreat from Li-ion for main battery use was plausibly described by them as a means to reduce risk--but the risk in question was that of delay in certification, not of hazard to the aircraft in service. As recently as October 21, 2013 Bloomberg carried a story asserting that Airbus said they planed to seek, obtain certfication for, and use Li-Ion after A350 service entry. Presumably they want back the weight loss of the late reversion to Ni-Cd, though in real life Ni-Cd has some other nasty properties besides the extra weight.
Possibly other aircraft besides the A380 use Li-Ion batteries in secondary systems?
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From: UK
In addition to the batteries in question there are two other batteries for standby power of the flight controls. No one seems to question these?
The s/by batteries were discussed at great length in some of the previous threads in the Tech Log forum.
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From: what U.S. calls ´old Europe´
In addition to the batteries in question there are two other batteries for standby power of the flight controls. No one seems to question these?
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From: somewhere
flight controls batteries
Quoting :
In addition to the batteries in question there are two other batteries for standby power of the flight controls. No one seems to question these?
IF similar to 777 , it should be 3 small batteries used during 1 minute on electrical transfers to power not 3 primary flight control computers but to power 3 components transforming variable power to 28DC for flight controls.
By the way on the 777 , there is a small battery 3 ft behind pilots .
In addition to the batteries in question there are two other batteries for standby power of the flight controls. No one seems to question these?
IF similar to 777 , it should be 3 small batteries used during 1 minute on electrical transfers to power not 3 primary flight control computers but to power 3 components transforming variable power to 28DC for flight controls.
By the way on the 777 , there is a small battery 3 ft behind pilots .
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From: Here and there
Norwegian seem to be having more trouble with their nightmareliner. Allegedly the pax were told by the cabin crew to delete any photos or video that had been taken.
Her spruter drivstoffet ut av flyvingen | Nordlys
Her spruter drivstoffet ut av flyvingen | Nordlys
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From: Up in the air. Sweden sometimes
Pax asked to delete pictures from leaking wing tank/Dreamliner
Passengers who filmed a leaking wing tank on a Norwegian Dreamliner during taxi, were asked by cabin crew to delete pictures. Well, they didn´t, you can follow the links from the article to photos and videos:
Dreamlinern blev ingen dröm för flygbolagen | SvD[svd.se/naringsliv]-[]-[Textlank]-[aftonbladet]-[]-[]
Dreamlinern blev ingen dröm för flygbolagen | SvD[svd.se/naringsliv]-[]-[Textlank]-[aftonbladet]-[]-[]
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From: Hadlow
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From: Here and there
http://www.pprune.org/rumours-news/5...ml#post8274569 see post 2026.
A different operator has also had a total transponder failure similar to the Lot incident.
Incident: Air India B788 near Berlin on Jan 19th 2014, complete loss of transponders
A different operator has also had a total transponder failure similar to the Lot incident.
Incident: Air India B788 near Berlin on Jan 19th 2014, complete loss of transponders
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From: Pasadena
Very foolish media handling on behalf of the cabin crew, then. I can't see a better way to make sure it ended up on Youtube/in the press.
Or were they just telling the camera-toting passengers to put their electronics away while taxying?
Did the passengers tell the cabin crew that they were filming substantial amounts of fuel falling out of the wing, from a place that it might not be expected to? Did the cabin crew tell the flight crew that this was going on?
Added. ah… fair enough - fuel would be expected to fall out from there - see later replies - it is the surge tank overflow spot. I'd expected that would be next to the vent pipe, but it's not, and at mid-chord underneath the wing.
Or were they just telling the camera-toting passengers to put their electronics away while taxying?
Did the passengers tell the cabin crew that they were filming substantial amounts of fuel falling out of the wing, from a place that it might not be expected to? Did the cabin crew tell the flight crew that this was going on?
Added. ah… fair enough - fuel would be expected to fall out from there - see later replies - it is the surge tank overflow spot. I'd expected that would be next to the vent pipe, but it's not, and at mid-chord underneath the wing.
Last edited by awblain; 21st January 2014 at 08:47. Reason: Fuel would be expected to come from there after all.
Pegase Driver
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From: Europe
The Norwegian fuel tank oveflow is not B787 specific. Saw it on other types, there are good technical explanations for it and I leave it to the secialists to reply .
What is far more worrying for me is the 2nd total loss of SSRs. Not only does the a/c becomes invisible to ATC ( as most new ATC systems are SSR only ) but also invisible to TCAS, the last safety net .
In both caes ( LOT last Sept and now here 2 days ago) the loss of SSR was detected by ATC , but one day it could remain undetected and a Brazilian scenario a la Gol/Legacy could repeat itself.
Not good .
What is far more worrying for me is the 2nd total loss of SSRs. Not only does the a/c becomes invisible to ATC ( as most new ATC systems are SSR only ) but also invisible to TCAS, the last safety net .
In both caes ( LOT last Sept and now here 2 days ago) the loss of SSR was detected by ATC , but one day it could remain undetected and a Brazilian scenario a la Gol/Legacy could repeat itself.
Not good .
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From: Florida and wherever my laptop is
What is far more worrying for me is the 2nd total loss of SSRs. Not only does the a/c becomes invisible to ATC ( as most new ATC systems are SSR only ) but also invisible to TCAS, the last safety net .
In both caes ( LOT last Sept and now here 2 days ago) the loss of SSR was detected by ATC , but one day it could remain undetected and a Brazilian scenario a la Gol/Legacy could repeat itself.
Not good .
In both caes ( LOT last Sept and now here 2 days ago) the loss of SSR was detected by ATC , but one day it could remain undetected and a Brazilian scenario a la Gol/Legacy could repeat itself.
Not good .
Pegase Driver
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From: Europe
Ian W :
Only money ( it usually is ) a Primary Radar is extremely expensive compared to an SSR one , and you need a mode S radar SSR anyway if you want to implement the future tools, so PRI becomes an expensive back up..
No, the military still have primary,(and other means ) to plot aircraft , it will only affect Civil ATC, Most Air defense systems track aircraft irrespective of Transponders.
Maybe in the past , never seen a total electric failure in a civil a/c from lightning in decades. But total loss of transponders due human error, oh yes..
Incidentally I was told this is not 2 cases of B787 total SSR loss in the last 6 months, , but 3, and with 3 different airframes. (AI had 2 of them )
So tell me again why it was a good idea to go to only cooperative surveillance systems?
a 9/11 issue where the bad guys know to turn off the transponder
you can get the same effect from a lightning strike
Incidentally I was told this is not 2 cases of B787 total SSR loss in the last 6 months, , but 3, and with 3 different airframes. (AI had 2 of them )
Last edited by ATC Watcher; 22nd January 2014 at 10:17. Reason: the aircraft departed London yesterday with transponder OK
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From: Japan
Looking for clues
Perhaps looking at one cell in isolation will advance the knowledge.
Japan 787 battery investigators look to latest overheating for clues to earlier meltdown ? Japan Today: Japan News and Discussion
"TOKYO —
Japanese investigators probing a lithium-ion battery meltdown on a Boeing 787 jetliner a year ago are looking at a battery that overheated on a Dreamliner in Tokyo this month to help unlock the cause of the earlier fire, an official from the Japan Transport Safety Board said on Wednesday.
The incident on board an ANA Holdings 787 a year ago left the battery charred and deformed, destroying evidence that would have pointed to a cause. The latest event on a parked Japan Airlines in a redesigned battery packed with insulation destroyed only one of eight cells.
“The remaining seven cells are untouched, and I think that is where the investigation will focus,” Masahiro Kudo, the lead investigator on the ANA battery said during a press briefing.
That overheating and one a few days earlier on a 787 parked at Boston’s Logan airport prompted aviation regulators in the U.S., Japan and elsewhere to ground the global fleet of Dreamliners for more than three months.
Authorities, without discovering the root cause of the meltdown, allowed Boeing to get its carbon composite back into the air after it redesigned the battery with insulation, a vent to eject any hot gases out of the aircraft, and encased it in a steel box to contain any fire. Finding the reason for the overheating could spur further design changes.
The United States National Transportation Safety Board (NTSB), which is looking at the incident in Boston, has sent accident investigator Mike Bauer to join the latest probe. The JAL Dreamliner’s battery emitted smoke at Tokyo’s Narita Airport just before takeoff. Japan’s Civil Aviation Bureau (JCAB) is in charge of the investigation.
In the year since the first overheating, the number of 787s in operation has more than doubled to 115 planes at 16 carriers. ANA is the world’s leading operator with 24 of the state-of-the-art jetliners built with carbon-fiber composite materials and a powerful electrical system to reduce weight and improve fuel efficiency.
(c) Copyright Thomson Reuters 2014."
Japan 787 battery investigators look to latest overheating for clues to earlier meltdown ? Japan Today: Japan News and Discussion
"TOKYO —
Japanese investigators probing a lithium-ion battery meltdown on a Boeing 787 jetliner a year ago are looking at a battery that overheated on a Dreamliner in Tokyo this month to help unlock the cause of the earlier fire, an official from the Japan Transport Safety Board said on Wednesday.
The incident on board an ANA Holdings 787 a year ago left the battery charred and deformed, destroying evidence that would have pointed to a cause. The latest event on a parked Japan Airlines in a redesigned battery packed with insulation destroyed only one of eight cells.
“The remaining seven cells are untouched, and I think that is where the investigation will focus,” Masahiro Kudo, the lead investigator on the ANA battery said during a press briefing.
That overheating and one a few days earlier on a 787 parked at Boston’s Logan airport prompted aviation regulators in the U.S., Japan and elsewhere to ground the global fleet of Dreamliners for more than three months.
Authorities, without discovering the root cause of the meltdown, allowed Boeing to get its carbon composite back into the air after it redesigned the battery with insulation, a vent to eject any hot gases out of the aircraft, and encased it in a steel box to contain any fire. Finding the reason for the overheating could spur further design changes.
The United States National Transportation Safety Board (NTSB), which is looking at the incident in Boston, has sent accident investigator Mike Bauer to join the latest probe. The JAL Dreamliner’s battery emitted smoke at Tokyo’s Narita Airport just before takeoff. Japan’s Civil Aviation Bureau (JCAB) is in charge of the investigation.
In the year since the first overheating, the number of 787s in operation has more than doubled to 115 planes at 16 carriers. ANA is the world’s leading operator with 24 of the state-of-the-art jetliners built with carbon-fiber composite materials and a powerful electrical system to reduce weight and improve fuel efficiency.
(c) Copyright Thomson Reuters 2014."
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From: England
Not sure if this has been posted before but this scientist appears to be suggesting that low energy nuclear reactions (LENR) might be occurring in lithium batteries and that this might account for some instances of combustion.
http://www.slideshare.net/lewisglars...diseaug-6-2013
I should point out that the authors views do not accord with the general scientific consensus which says LENR is impossible. His company also claims to be trying to commercialise LENR for power generation. I understand he is one of the few people to have had a paper on LENR published in a peer reviewed journal.
http://www.slideshare.net/lewisglars...diseaug-6-2013
I should point out that the authors views do not accord with the general scientific consensus which says LENR is impossible. His company also claims to be trying to commercialise LENR for power generation. I understand he is one of the few people to have had a paper on LENR published in a peer reviewed journal.