Glad I'm flying a Dreamliner(tm) instead
They were so safely designed that they were granted a new extended 330minute ETOPS on launch without any in-service qualifying period.
The US Federal Aviation Administration (FAA) has grounded all Boeing 787 Dreamliners over fears that its lithium-ion batteries are unsafe, after they were linked to two aircraft fires in the space of ten days. "The battery failures resulted in release of flammable electrolytes, heat damage, and smoke on two Model 787 airplanes …
Fly in an aircraft that has a 100% safety record, never fly with an airline that has a 100% safety record. Never fly in a new aircraft type that has never crashed.
Statistically it's only a matter of time, whereas the others that have crashed failed etc have had time to put the flaws and systems right and are statistically less likely to fail.
I think what you are saying is complete nonsense.
Number of crashes or lack thereof is totally meaningless unless you take into consideration types of failures, causes of accidents, number of flight hours and cycles accumulated per fleet and per airframe between the accidents, type of engines, avionics and other equipment each airframe carried.
According to your logic it is safer to fly on some Nigerian local carrier than on the BA because the Nigerian airline would have had many more accidents.
That is an odd application of statistics....
Surely an airline that has a 100% safety record means their doing things right...
Would I trust an airline that had a crash caused by negligence? Not a chance..
No aircraft is perfect, they will all have issues, I choose an airline that hires good pilots & good engineers...
> The Dreamliner's never-before-seen range is [going to] change how the global routes are put together
I don't believe that the absolute aircraft range is the limiting factor in how global routes are put together. There's the passengers' tolerance for being cooped up in a flying tube for more than 11 or 12 hours at a stretch, there's the issue of feeding, watering, entertaining and mucking out the said passengers, and staff/aircrew matters. If you're going to have very long flight times, your passenger density would have to be reduced to mitigate any or all of those.
Then there's demand. Even if one could fly from London Heathrow to Auckland directly, there might not be sufficient demand for that service, whereas stopping en route, as NZ002 does at Los Angeles, means that you can exploit the demand for LHR-LAX and LAX-AKL with the same aircraft.
...good old Yuasa, you know the people that make lead-acid gel cells and the like.
I'm not certain of the reason for the lithium ion batteries other than saving of weight and a bit of volume. The ones causing problems are part of the APU start system but I'm uncertain about how much current they have to supply in flight, I would expect that to come from the engine generators with maybe some ability in the batteries to smooth out heavy current blips such as when the flaps are lowered.
Experience shows that an on board fire of this type that can't be contained needs the aircraft to be on the ground within 10 minutes for the fire to be survivable. Smoke masks for the pilots are only of so much use, the UPS 747 freighter that went down in Dubai crashed because the crew could not see their instruments, radios or indeed anything.
I think the weight saving is the key factor, given the concentration on building as much of the plane out of composites as possible.
As for the APU, it has to be capable of taking over the plane's electrical systems within a few seconds of engine shutdown/failure, so I would imagine there's a certain amount of low level power from the batteries for that eventuality - the batteries might also be getting charged in-flight to compensate for that and recharge the usage of the on-ground startup of the APU.
"Boeing 787 aircraft must demonstrate to the Federal Aviation Administration (FAA) that the batteries are safe."
There is a range of FAA language with subtle meanings, but "MUST DEMONSTRATE ... SAFE" is big-stick stuff
Basically it means rip them out if you want a hope of the plane flying this year.
Just about the worst scenario you can have.
Engines throwing blades, yea, aircraft are designed to cope with that. The chickens attest to that & the more engines the better.
Fire... especially anywhere in the fuselage. Bad, bad, bad.
Boeing has messed up here, bad. I spent some around Boeing when they kicked off the triple 7 program & I was highly impressed at what I saw.
>Boeing ... kicked off the triple 7 program & I was highly impressed at what I saw.
With their plan to outsource not only manufacture but design of each part to the lowest bidder, and then have each of those suppliers contract it out to their lowest bidder and so on with no oversight?
I have to buy fscking USB cables for $$$ from an ISO certified supplier and have a formal process of validating and inspecting that supplier and yet the design of bits of 787 get outsourced so far down the tree that Boeing have to formally admit they have no idea who DESIGNED some parts.
To date, no large commercial airliner has even landed intact on open ocean (despite what the pretty picture in the kiss-your-arse-goodbye folder shows)
What a load of old rubbish! I saw a documentary, literally years ago, which showed a plane that survived this. It was even stuck underwater for hours, and all the passengers were still rescued.
What plane was it again? Oh yes, I remember. It was one of those atomic powered Fireflashes. I guess it would have been a chap called Gordon Tracey who did the underwater cleverness to save the day...
To see if someone can manage to blame Sony for this one too...
Seriously though, it's a bit of a catch-22 - you need batteries for electronics, but the more batteries, the increased risk of one of something going wrong/melting down/exploding and destroying the electronics - which, because everything relies on electronics, makes flying the plane difficult/impossible, which prompts the need for more failsafes/backups/redundancies, which requires more electronics, which requires more batteries...
Does anyone know (I'm sure many here do) if they're still required to have analog instrument backups in place? or have they been phased out completely?
...why they used Li-ion batteries, which are known in model flying circles amongst other places for their flamability, and not LiFePO4, which do not have this problem. LiFe phosphate batteries have a track record of safe use in aircraft.
The Antares 20E uses them and has done for several years.
From what I've read elsewhere, basically power to weight ratio. The Cobalt-Oxide based Li batteries are best for that, but have the unfortunate heat problem that's now manifesting itself. As noted above, it's the same technology used in cellphone & laptop batteries (and the Tesla Roadster), unfortunately with similar meltdown issues.
The other option may have been the Manganese based batteries more commonly used in other electric cars (the Volt et al), but whilst they don't overheat as easily they also don't supply as much juice for their weight. And it would be similar with the LiFePO4 ones - the whole point is weight-saving (along with the carbon fibre/plastic usage in the similar vein).
The Dreamliner idea of using electrics rather than tapping off some of the engine hot gas to support the sub-systems is an interesting one (for increasing fuel efficiency), but one can't help thinking that the con's of that idea may not have been considered quite as far as the pro's were...
is why Boeing are installing a technology that has been banned from being transported on airplanes by many airlines (with certain exceptions granted, like individual batteries installed in devices), and by several countries outright: Li-Ion batteries using LiCo. Several bans on transporting such devices had been in effect long before the 787 entered service.
Let's see if I got this right:-
Sending Li-Ion batteries as freight in the hold (where there's an active suppressant system) is banned or at least highly regulated, but having them performing under load in the electronics bay (where there's only a smoke detector) is OK.
There has been a great deal of news (and a couple of crashes) laid at the feet of Li-Ion batteries, yet Mr Boeing (and presumably the certification bods at the FAA) have seen that this is a good idea.
So that's a power/fire source that has a track record of doing firework's imitations providing power in an aircraft that's partially made of composite materials whose flammability is still a matter of concern/debate.
What was the saying about putting a host of new technologies all together in the one place?
I really hope that Boeing / NTSC / FAA / etc can get their act together and sort this out before we have a major incident/accident with loss of life.
The battery pack that failed was used to start the Auxiliary Power Unit (APU). The APU provides power to the plane when the engines are not running, ie: on the ground. When the engines are running, there is plenty of power to operate the aircraft and supply passengers with plug in points. The failure of this pack was while the plane was on the ground and all of the passengers had been off the plane for some time. The APU is not normally used while the plane is in flight unless the plane loses all of it's engines (or at least all of the engines with alternators to provide electricity). The article is poorly written and suggests to the reader that the battery pack might burst into flames while the plane is flying. That's not very likely. Improperly charging, over-discharging or puncturing the packs can lead to fires. It is certain that there would be a sophisticated battery management circuit to keep track of charge and discharge rates. Perhaps there needs to be another layer of protection and some more "margin" in the design. It's very surprising that there wasn't a fire extinguisher system covering the battery pack give the history of Li chemistry battery fires.
I'm sure that Boeing (Boing) specified Li batteries to shave some weight off. They may be questioning that decision now, but it is a certainty that the battery pack had been extensively tested to be certified for use on an aircraft. Anything of an electronic nature must be certified if it's to go on an aircraft and it's an time intensive, rigorous and expensive process.
I've used Li batteries for rocket avionics systems that I have designed and built with a decent track record. One certainly must know how handle the beasties or they will bite. I hope that Boeing and/or the FAA will release their findings on a probable cause for the failure. I'm interested from a professional stand point. I would not be worried flying on a 787.
>battery pack might burst into flames while the plane is flying
Unused, sealed, disconnected, in their shipping boxes Li batteries have caught fire and destroyed aircraft
it's not unreasonable that one connected to a complex set of aircraft systems, even if nominally not in use , could catch fire
>Anything of an electronic nature must be certified if it's to go on an aircraft
Certified yes, - tested, well err .......
A lot of avition safety comes from the methodology of; we have always done it like this and it worked. That is coupled with a lot of certification to show that you are doing it exactly like you have always done it, and that nobody in the supply chain has changed anything without telling you. That's why an aircraft coffee machine costs $5000.
The 787, like a lot of modern planes and most modern military kit, uses a lot of COTS systems with the assumption that if they have been used for years in an office they are well known. This hasn't always proved the case when they are put in more challenging applications
The problem here is that the system design was outsourced by Boeing (who know lots about planes) to Thales (who know about electronics) to Yusa (who know about batteries) to god-knows-who subcontractor
And as long as everybody filled in the paperwork it was assumed this was as good as Boeing designing it themselves.
Most of your post post seems to be guesswork - viz.:
"That's not very likely."
"It is certain that there would be a sophisticated battery management circuit to keep track of charge and discharge rates."
"but it is a certainty that the battery pack had been extensively tested"
You don't know, do you?
Not to be rude..but if you read the *actual* news...it states
"The Federal Aviation Authority (FAA) issued the order after a 787 operated by Japan’s All Nippon Airways (ANA) made an emergency landing outside Tokyo on Wednesday. The plane landed early after cockpit controls warned of battery error and indicated smoke."
So yeah, the battery did exactly what you said it couldn't do..and malfunctioned IN FLIGHT.
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