DreamLiner and Li-ion
 

So they've just discovered Li-ion can be a fire risk?

--
*Parenthetical remarks (however relevant) are (usually) unnecessary *

Dave Plowman London SW
To e-mail, change noise into sound.

DreamLiner and Li-ion
 

En el artículo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

http://www.theregister.co.uk/2013/01...787_batteries/

http://www.thetimes.co.uk/tto/multim...0__374392c.jpg

Wouldn't be too happy flying with that happening under my feet.

--
(\_/)
(='.'=)
(")_(")

DreamLiner and Li-ion
 

On 18/01/2013 08:51, Mike Tomlinson wrote:
En el artículo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

Not really surprising. Li-ion is volatile chemistry and if it gets
slightly maltreated can go into thermal runaway self heating. That is
the price for the energy density vs weight trade-off.

http://www.theregister.co.uk/2013/01...787_batteries/

http://www.thetimes.co.uk/tto/multim...0__374392c.jpg

Wouldn't be too happy flying with that happening under my feet.

The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

--
Regards,
Martin Brown

DreamLiner and Li-ion
 

On Fri, 18 Jan 2013 00:12:50 +0000 (GMT), Dave Plowman (News) wrote:

So they've just discovered Li-ion can be a fire risk?

They've know about it for a long time. Have a google for the restrictions
put on Li technology batteries in baggage/freight...

Seems like a major cockup to use Li technology batteries as part of an
aircraft without taking some very careful measures to ensure they won't
catch fire. The big problem with Li batteries is that they contain their
own oxygen, so are self sustaining. Fire supression systems that rely on
removing/reducing the available oxygen, inert gas, foam, dry powder, etc
don't work.

--
Cheers
Dave.

DreamLiner and Li-ion
 

Oh really, well any battery with the kind of current capabilities can be a
fire risk. I just wonder if they enclose them in flame retardant and
explosion proof containers. this apparently is the case with manned space
flight devices, though I'm not sure about the laptops on the ISS, certainly
the sat phone used in the soyuz has the battery protected this way.
Brian

--
From the Sofa of Brian Gaff Reply address is active
"Dave Plowman (News)" wrote in message
...
So they've just discovered Li-ion can be a fire risk?

--
*Parenthetical remarks (however relevant) are (usually) unnecessary *

Dave Plowman London SW
To e-mail, change noise into sound.

DreamLiner and Li-ion
 

In article ,
Brian Gaff wrote:
Oh really, well any battery with the kind of current capabilities can be
a fire risk.

It can be if it is shorted, etc. But lithium types appear to be capable of
being this on their own.

--
*If your feet smell and your nose runs, you're built upside down.

Dave Plowman London SW
To e-mail, change noise into sound.

DreamLiner and Li-ion
 

On 18.01.2013 09:51, Mike Tomlinson wrote:
En el artÃ*culo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

http://www.theregister.co.uk/2013/01...787_batteries/

http://www.thetimes.co.uk/tto/multim...0__374392c.jpg

Wouldn't be too happy flying with that happening under my feet.

I would be quite happy with that.
The chance of dying in a plane is
far less likely then dying in your home:
http://www.phyast.pitt.edu/~blc/book/chapter8.html
LOSS OF LIFE EXPECTANCY (LLE) DUE TO VARIOUS RISKS
TABLE 1
Activity or risk* LLE (days)
Living in poverty 3500
Being male (vs. female) 2800
Cigarettes (male) 2300
Heart disease* 2100
Being unmarried 2000
....
Occupational accidents 74
....
Airline crashes* 1
Dam failures* 1
Living near nuclear plant 0.4
All electricity nuclear (NRC)* 0.04
--
jo
"We should never so entirely avoid danger as to appear
irresolute and cowardly. But, at the same time, we should
avoid unnecessarily exposing ourselves to danger, than
which nothing can be more foolish. [Cicero]"

DreamLiner and Li-ion
 

On 18/01/2013 10:51, Jo Stein wrote:
On 18.01.2013 09:51, Mike Tomlinson wrote:
En el artÃ*culo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

http://www.theregister.co.uk/2013/01...787_batteries/

http://www.thetimes.co.uk/tto/multim...0__374392c.jpg


Wouldn't be too happy flying with that happening under my feet.

I would be quite happy with that.
The chance of dying in a plane is
far less likely then dying in your home:
http://www.phyast.pitt.edu/~blc/book/chapter8.html
LOSS OF LIFE EXPECTANCY (LLE) DUE TO VARIOUS RISKS
TABLE 1
Activity or risk* LLE (days)
Living in poverty 3500
Being male (vs. female) 2800
Cigarettes (male) 2300
Heart disease* 2100
Being unmarried 2000
....
Occupational accidents 74
....
Airline crashes* 1
Dam failures* 1
Living near nuclear plant 0.4
All electricity nuclear (NRC)* 0.04

Whilst we have reasonable statistics to reassure re the general safety
of flying, I feel that we do not yet have sufficient knowledge of the
safety of Dreamliner 787s. Only in service since October 2011. So
anything that takes a couple of years to surface...

BTW, how long do lappie batteries typically last? Seem to remember they
start failing in their second year and often get worse over the next two
or three years.

--
Rod

DreamLiner and Li-ion
 

On 18/01/2013 09:28, Martin Brown wrote:
On 18/01/2013 08:51, Mike Tomlinson wrote:
En el artículo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

Not really surprising. Li-ion is volatile chemistry and if it gets
slightly maltreated can go into thermal runaway self heating. That is
the price for the energy density vs weight trade-off.

http://www.theregister.co.uk/2013/01...787_batteries/

http://www.thetimes.co.uk/tto/multim...0__374392c.jpg


Wouldn't be too happy flying with that happening under my feet.

The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

Possibly not. The undercarriage is only really essential if you want to
be able to take off again after the landing.

Colin Bignell

DreamLiner and Li-ion
 

On Fri, 18 Jan 2013 11:17:37 +0000
Nightjar wrote:

On 18/01/2013 09:28, Martin Brown wrote:
On 18/01/2013 08:51, Mike Tomlinson wrote:
En el artÃ*culo , Dave Plowman
(News) escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

Not really surprising. Li-ion is volatile chemistry and if it gets
slightly maltreated can go into thermal runaway self heating. That
is the price for the energy density vs weight trade-off.

http://www.theregister.co.uk/2013/01...787_batteries/

http://www.thetimes.co.uk/tto/multim...0__374392c.jpg


Wouldn't be too happy flying with that happening under my feet.

The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

Possibly not. The undercarriage is only really essential if you want
to be able to take off again after the landing.

Colin Bignell


From a report of the earlier incident:
"In todays problem, the automated landing gear did not operate, but
the pilot was able to lower the landing gear manually €“ using gravity €“
and landed on the plane's second approach to the runway."

http://www.computerworlduk.com/news/...-japan-flight/

So, kind-of, sort-of, maybe. As long as the undercarriage doors open.
--
Davey.

DreamLiner and Li-ion
 

On 18/01/2013 10:51, Jo Stein wrote:
On 18.01.2013 09:51, Mike Tomlinson wrote:
En el artÃ*culo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

http://www.theregister.co.uk/2013/01...787_batteries/

http://www.thetimes.co.uk/tto/multim...0__374392c.jpg


Wouldn't be too happy flying with that happening under my feet.

I would be quite happy with that.
The chance of dying in a plane is
far less likely then dying in your home:

That does rather depend upon the aircraft.

Colin Bignell

DreamLiner and Li-ion
 

Dave Plowman (News) wrote:
In article ,
Brian Gaff wrote:
Oh really, well any battery with the kind of current capabilities can be
a fire risk.

It can be if it is shorted, etc. But lithium types appear to be capable of
being this on their own.

Some laptop suppliers had to recall a lot of batteries a while ago....

Didn't some Apples burst into flames?

--
Tciao for Now!

John.

DreamLiner and Li-ion
 

On 18.01.2013 12:30, Nightjar wrote:
On 18/01/2013 10:51, Jo Stein wrote:
On 18.01.2013 09:51, Mike Tomlinson wrote:
En el artÃ*culo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

http://www.theregister.co.uk/2013/01...787_batteries/


http://www.thetimes.co.uk/tto/multim...0__374392c.jpg



Wouldn't be too happy flying with that happening under my feet.

I would be quite happy with that.
The chance of dying in a plane is
far less likely then dying in your home:

That does rather depend upon the aircraft.

Why do people clap their hands after a landing?
Because we are afraid of heights.
Why are we afraid of heights?
Because of evolution, which also explains why
goats are not at all afraid of heights.

I will prefer an Airbus A350 when flying long distance,
and my choice is not based on irrational fear:
http://en.wikipedia.org/wiki/Boeing_...and_deliveries
http://en.wikipedia.org/wiki/Airbus_...and_deliveries
--
jo
"We should never so entirely avoid danger as to appear
irresolute and cowardly. But, at the same time, we should
avoid unnecessarily exposing ourselves to danger, than
which nothing can be more foolish. [Cicero]"

DreamLiner and Li-ion
 

On 18/01/2013 11:17, Nightjar wrote:


Possibly not. The undercarriage is only really essential if you want to
be able to take off again after the landing.

Colin Bignell

Or the passengers want their luggage not strewn across the, I was going
to say "runway", but maybe "wherever they happen to land".

--
Rod

DreamLiner and Li-ion
 

On 18/01/2013 00:12, Dave Plowman (News) wrote:
So they've just discovered Li-ion can be a fire risk?


And started recruiting people who might know something:

Electronic / Electrical Test Engineer (Lithium, Battery)

Electronic / Electrical Test Engineer (Lithium Batteries)

Oxfordshire

To £27k - £32k + benefits

An excellent opportunity has arisen for an experienced Battery Test
Engineer to join a rapidly expanding technology company specializing in
the Design and Manufacture of Next Generation Lithium Battery technology.
The ideal candidate will be a Test Engineer with both the technical and
theoretical knowledge to provide a battery testing service within the
R&D group working with minimum supervision and providing technical
competency in lithium based cells or batteries testing and quality
assurance using internal or external facilities. An experienced
candidate is preferred however an outstanding individual with an
excellent understanding of the basic electronic / electrical principles'
would be considered.

Key areas of test duties
* Cell testing to the Test department specifications on prototype Li-S
cells.
* Cell processing and quality assurance of Li-S cells manufactured for
customer battery projects.
* Testing products to customer specifications and in accordance with
Test department quality specifications.
* Timely delivery to the customer ensuring that all batteries are built
and tested ahead of the dispatch date.

Main duties:
- Electrical verification by checking the voltage of cells etc
- Test harnesses design and production
- Safety handling of lithium based cells and batteries
- Document writing - SOPS, reports etc
- Data gathering and analysing
- Basic Quality assurance
- Developing test plans and strategies
- Use of Maccor cells and batteries electrical cycling test equipment
- Technical support to the R&D team
- Safety tests on Li-S cells and batteries (nail penetration, short
circuit, overcharge test, thermal stability test)
- Bonding and isolation tests
- Destructive parts analysis on Li-S cells in a dry room
- Supporting the maintenance of internal Test facilities and test equipment
- Developing test equipment and procedures

Main skills:
- Basic practical electrical/electronic knowledge (Ohm's law,
Kirchhoff's laws etc)
- Battery or cell electrical and mechanical testing (preferably lithium
based batteries)
- Ability to use Maccor cyclers
- Able to work with mechanical and electrical drawings
- Knowledge of working with testing equipment: DVMs, PSUs etc
- Excel and Word basic principles
- Basic soldering skills
- Thermal cycling of a battery products

Education: HNC/HND/BTEC in Electrical/Electronic Engineering +
experience in Li based cell and battery testing

:-)

--
Rod

DreamLiner and Li-ion
 

"Martin Brown" wrote in message
...
On 18/01/2013 08:51, Mike Tomlinson wrote:
En el artículo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

Not really surprising. Li-ion is volatile chemistry and if it gets
slightly maltreated can go into thermal runaway self heating. That is the
price for the energy density vs weight trade-off.

http://www.theregister.co.uk/2013/01...787_batteries/

http://www.thetimes.co.uk/tto/multim...0__374392c.jpg

Wouldn't be too happy flying with that happening under my feet.

The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some manual
way of lowering the undercarriage for landing in extremis.

Apparently, these batteries are not used to "fly" the plane (presumably that
is done using electricity generated by the engines somehow)

They are only used for power when the plane is on the ground

DreamLiner and Li-ion
 

polygonum wrote:
On 18/01/2013 10:51, Jo Stein wrote:
On 18.01.2013 09:51, Mike Tomlinson wrote:
En el artÃ*culo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

http://www.theregister.co.uk/2013/01...787_batteries/

http://www.thetimes.co.uk/tto/multim...0__374392c.jpg


Wouldn't be too happy flying with that happening under my feet.

I would be quite happy with that.
The chance of dying in a plane is
far less likely then dying in your home:
http://www.phyast.pitt.edu/~blc/book/chapter8.html
LOSS OF LIFE EXPECTANCY (LLE) DUE TO VARIOUS RISKS
TABLE 1
Activity or risk* LLE (days)
Living in poverty 3500
Being male (vs. female) 2800
Cigarettes (male) 2300
Heart disease* 2100
Being unmarried 2000
....
Occupational accidents 74
....
Airline crashes* 1
Dam failures* 1
Living near nuclear plant 0.4
All electricity nuclear (NRC)* 0.04

Whilst we have reasonable statistics to reassure re the general safety of
flying, I feel that we do not yet have sufficient knowledge of the safety
of Dreamliner 787s. Only in service since October 2011. So anything that
takes a couple of years to surface...

BTW, how long do lappie batteries typically last? Seem to remember they
start failing in their second year and often get worse over the next two or three years.


More relevant though is how often do they burst into flames? Yes, it has
happened but when you consider the millions of batteries that must have
been produced it seems as if they've "tamed the beast" and made them
acceptably safe.

Tim

DreamLiner and Li-ion
 

On 18/01/2013 13:11, tim..... wrote:

"Martin Brown" wrote in message
...
On 18/01/2013 08:51, Mike Tomlinson wrote:
En el artículo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

Not really surprising. Li-ion is volatile chemistry and if it gets
slightly maltreated can go into thermal runaway self heating. That is
the price for the energy density vs weight trade-off.

http://www.theregister.co.uk/2013/01...787_batteries/


http://www.thetimes.co.uk/tto/multim...0__374392c.jpg


Wouldn't be too happy flying with that happening under my feet.

The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

Apparently, these batteries are not used to "fly" the plane (presumably
that is done using electricity generated by the engines somehow)

They are only used for power when the plane is on the ground



Suspect that they get recharged (if needed) in flight. So they might not
need to provide power in the air but, one imagines, could as easily take
up smoking in flight as on the ground.

--
Rod

DreamLiner and Li-ion
 

In article ,
tim..... wrote:
The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

Apparently, these batteries are not used to "fly" the plane (presumably
that is done using electricity generated by the engines somehow)

They are only used for power when the plane is on the ground

The battery in your car doesn't do much when the car is running - but that
doesn't make it unimportant.

--
*If at first you don't succeed, destroy all evidence that you tried *

Dave Plowman London SW
To e-mail, change noise into sound.

DreamLiner and Li-ion
 

In article ,
polygonum wrote:
BTW, how long do lappie batteries typically last? Seem to remember they
start failing in their second year and often get worse over the next two
or three years.

Mine was hardly ever used since it was plugged into mains most of the
time, and did about 2 years. Seems they don't like being kept fully float
charged.

The replacement is kept out of the laptop, and only fitted when needed.

--
*Ah, I see the f**k-up fairy has visited us again

Dave Plowman London SW
To e-mail, change noise into sound.

DreamLiner and Li-ion
 

polygonum wrote:

On 18/01/2013 00:12, Dave Plowman (News) wrote:
So they've just discovered Li-ion can be a fire risk?


And started recruiting people who might know something:

When I worked for a client that did a lot of research in this area they
had a visit from a Japanese Professor who was giving lectures on LiIon
design. He stated that the current design of LiIon cells was all wrong,
leading to an increased risk of overheating and fire, but the
manufacturers had invested a lot in the design and couldn't back out of
bad design decisions quickly.

I wish I could remember what the suggested fix was.

Oh hang on, ancient brain cells ticking over, it may have been that he
was proposing a design for solid polymer electrolytes.

--
Burn Hollywood burn, burn down to the ground

DreamLiner and Li-ion
 

"polygonum" wrote in message
...
On 18/01/2013 13:11, tim..... wrote:

"Martin Brown" wrote in message
...
On 18/01/2013 08:51, Mike Tomlinson wrote:
En el artículo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

Not really surprising. Li-ion is volatile chemistry and if it gets
slightly maltreated can go into thermal runaway self heating. That is
the price for the energy density vs weight trade-off.

http://www.theregister.co.uk/2013/01...787_batteries/


http://www.thetimes.co.uk/tto/multim...0__374392c.jpg


Wouldn't be too happy flying with that happening under my feet.

The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

Apparently, these batteries are not used to "fly" the plane (presumably
that is done using electricity generated by the engines somehow)

They are only used for power when the plane is on the ground



Suspect that they get recharged (if needed) in flight. So they might not
need to provide power in the air but, one imagines, could as easily take
up smoking in flight as on the ground.

Oh I agree,

the point is such an event is not going to make the plane fall out of the
sky because the controls no longer work

tim

DreamLiner and Li-ion
 

"Dave Plowman (News)" wrote in message
...
In article ,
tim..... wrote:
The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

Apparently, these batteries are not used to "fly" the plane (presumably
that is done using electricity generated by the engines somehow)

They are only used for power when the plane is on the ground

The battery in your car doesn't do much when the car is running - but that
doesn't make it unimportant.

No, but in this case, they are (when in the air)

tim

DreamLiner and Li-ion
 

In message , tim.....
writes

"Martin Brown" wrote in message
...
On 18/01/2013 08:51, Mike Tomlinson wrote:
En el artículo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

Not really surprising. Li-ion is volatile chemistry and if it gets
slightly maltreated can go into thermal runaway self heating. That is
the price for the energy density vs weight trade-off.

http://www.theregister.co.uk/2013/01...787_batteries/


http://www.thetimes.co.uk/tto/multim...19910330__3743
92c.jpg

Wouldn't be too happy flying with that happening under my feet.

The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

Apparently, these batteries are not used to "fly" the plane (presumably
that is done using electricity generated by the engines somehow)

They are only used for power when the plane is on the ground


They used to have an emergency generator with a propellor strung
underneath but don't know if that is still the case.
--
bert

DreamLiner and Li-ion
 

In message , Jo Stein
writes
The chance of dying in a plane is
far less likely then dying in your home:
Generally yes, but if a particular plane has a specific safety problem
then the generalisation no longer applies to that plane - e.g. Comet.
That is why when such an issue is identified the fleet is grounded.
--
bert

DreamLiner and Li-ion
 

En el artículo , Jo Stein
escribió:

Why do people clap their hands after a landing?

Because they're idiots?

--
(\_/)
(='.'=)
(")_(")

DreamLiner and Li-ion
 

On 18/01/2013 13:59, bert wrote:
In message , tim.....
writes

"Martin Brown" wrote in message
...
On 18/01/2013 08:51, Mike Tomlinson wrote:
En el artículo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

Not really surprising. Li-ion is volatile chemistry and if it gets
slightly maltreated can go into thermal runaway self heating. That is
the price for the energy density vs weight trade-off.

http://www.theregister.co.uk/2013/01...787_batteries/



http://www.thetimes.co.uk/tto/multim...19910330__3743
92c.jpg

Wouldn't be too happy flying with that happening under my feet.

The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

Apparently, these batteries are not used to "fly" the plane
(presumably that is done using electricity generated by the engines
somehow)

They are only used for power when the plane is on the ground


They used to have an emergency generator with a propellor strung
underneath but don't know if that is still the case.

Most have an auxiliary engine / generator in the tail. I guess the idea
of a battery was to dispense with this, making the aircraft cheaper and
possibly more aerodynamic.

Not sure what use a propeller is for generating power whilst on the ground.

DreamLiner and Li-ion
 

On 18/01/13 13:54, tim..... wrote:

"polygonum" wrote in message
...
On 18/01/2013 13:11, tim..... wrote:

"Martin Brown" wrote in message
...
On 18/01/2013 08:51, Mike Tomlinson wrote:
En el artÃ*culo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

Not really surprising. Li-ion is volatile chemistry and if it gets
slightly maltreated can go into thermal runaway self heating. That is
the price for the energy density vs weight trade-off.

http://www.theregister.co.uk/2013/01...787_batteries/



http://www.thetimes.co.uk/tto/multim...0__374392c.jpg



Wouldn't be too happy flying with that happening under my feet.

The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

Apparently, these batteries are not used to "fly" the plane (presumably
that is done using electricity generated by the engines somehow)

They are only used for power when the plane is on the ground



Suspect that they get recharged (if needed) in flight. So they might
not need to provide power in the air but, one imagines, could as
easily take up smoking in flight as on the ground.

Oh I agree,

the point is such an event is not going to make the plane fall out of
the sky because the controls no longer work

tim




No, but it might easily make the gear not come down. Batteries are
useful ways to absorb PEAK loads.

Aircraft on the ground have umbilcals IIRC.


--
Ineptocracy

(in-ep-toc-ra-cy) €“ a system of government where the least capable to
lead are elected by the least capable of producing, and where the
members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.

DreamLiner and Li-ion
 

On Fri, 18 Jan 2013 15:11:13 +0000
Fredxx wrote:

On 18/01/2013 13:59, bert wrote:
In message , tim.....
writes

"Martin Brown" wrote in message
...
On 18/01/2013 08:51, Mike Tomlinson wrote:
En el artÃ*culo , Dave Plowman
(News) escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

Not really surprising. Li-ion is volatile chemistry and if it gets
slightly maltreated can go into thermal runaway self heating.
That is the price for the energy density vs weight trade-off.

http://www.theregister.co.uk/2013/01...787_batteries/



http://www.thetimes.co.uk/tto/multim...19910330__3743
92c.jpg

Wouldn't be too happy flying with that happening under my feet.

The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is
no independent hydraulic system although presumable there must be
some manual way of lowering the undercarriage for landing in
extremis.

Apparently, these batteries are not used to "fly" the plane
(presumably that is done using electricity generated by the engines
somehow)

They are only used for power when the plane is on the ground


They used to have an emergency generator with a propellor strung
underneath but don't know if that is still the case.

Most have an auxiliary engine / generator in the tail. I guess the
idea of a battery was to dispense with this, making the aircraft
cheaper and possibly more aerodynamic.

Not sure what use a propeller is for generating power whilst on the
ground.

About as much as the wind turbines blighting our countryside, ie "not a
lot".
--
Davey.

DreamLiner and Li-ion
 

On 18/01/2013 11:50, Jo Stein wrote:
On 18.01.2013 12:30, Nightjar wrote:
On 18/01/2013 10:51, Jo Stein wrote:
On 18.01.2013 09:51, Mike Tomlinson wrote:
En el artÃ*culo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

http://www.theregister.co.uk/2013/01...787_batteries/



http://www.thetimes.co.uk/tto/multim...0__374392c.jpg




Wouldn't be too happy flying with that happening under my feet.

I would be quite happy with that.
The chance of dying in a plane is
far less likely then dying in your home:

That does rather depend upon the aircraft.

Why do people clap their hands after a landing?

I've never been on a flight where anybody did that.

Because we are afraid of heights.

If they do it through fear, it is more probably a fear of flying.

Why are we afraid of heights?

Not everybody is
http://en.wikipedia.org/wiki/File:Lu...aper-c1932.jpg

Because of evolution,

The fact that entire groups of peoples do not fear heights suggests it
is nurture, rather than nature.

which also explains why
goats are not at all afraid of heights.

Have you ever asked a goat whether it is unafraid or simply confronting
its fear?

Colin Bignell

DreamLiner and Li-ion
 

On 18.01.2013 15:17, Mike Tomlinson wrote:
En el artÃ*culo , Jo Stein
escribió:

Why do people clap their hands after a landing?

Because they're idiots?

Because they are made that way by evolution.

Science is difficult and require a lot of explanation.
You are afraid of heights because you are made by parents
that are afraid of heights.
People not afraid of heights fell down from cliffs and
did not leave children around; their genes are gone.

Why are goats not afraid of heights?
Because goats afraid of heights failed in the struggle for life.
They died from starvation.
You see?

If people were less afraid of height they would have
forgotten to clap their hands after landing.
I never clap my hands when landing because I am busy
studying those passenger that clap their hands.
--
jo
A great deal of the universe does not need any explanation.
Elephants, for instance. Once molecules have learnt to compete
and to create other molecules in their own image, elephants,
and things resembling elephants, will in due course be found
roaming around the countryside
...
Some of the things resembling elephants will be men. --P. W. Atkins

DreamLiner and Li-ion
 

On 18/01/2013 11:55, polygonum wrote:
On 18/01/2013 11:17, Nightjar wrote:


Possibly not. The undercarriage is only really essential if you want to
be able to take off again after the landing.

Colin Bignell

Or the passengers want their luggage not strewn across the, I was going
to say "runway", but maybe "wherever they happen to land".

The damage to the aircraft is usually quite minimal

http://www.youtube.com/watch?v=mXWaBrE9_qo

Colin Bignell

DreamLiner and Li-ion
 

In article ,
"tim....." writes:
Apparently, these batteries are not used to "fly" the plane (presumably that
is done using electricity generated by the engines somehow)

They are only used for power when the plane is on the ground

I heard that comment too, but I find it very hard to believe.
Why would you add that sort of weight to a plane, which it
doesn't use when flying, when planes on the ground are powered
by umbilicals anyway when the engines are off?

Sounds like a bit of technology whose only real purpose in life
is to fail...

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

DreamLiner and Li-ion
 

On 18/01/2013 11:28, Davey wrote:
On Fri, 18 Jan 2013 11:17:37 +0000
Nightjar wrote:

On 18/01/2013 09:28, Martin Brown wrote:
....
The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

Possibly not. The undercarriage is only really essential if you want
to be able to take off again after the landing.

Colin Bignell


From a report of the earlier incident:
"In todays problem, the automated landing gear did not operate, but
the pilot was able to lower the landing gear manually €“ using gravity €“
and landed on the plane's second approach to the runway."

http://www.computerworlduk.com/news/...-japan-flight/

So, kind-of, sort-of, maybe. As long as the undercarriage doors open.

There is also the possibility when relying upon gravity that the gear
might drop but fail to lock in position, which could result in it
collapsing after landing.

Colin Bignell

DreamLiner and Li-ion
 

"polygonum" wrote in message
...
On 18/01/2013 10:51, Jo Stein wrote:
On 18.01.2013 09:51, Mike Tomlinson wrote:
En el artÃ*culo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

http://www.theregister.co.uk/2013/01...787_batteries/

http://www.thetimes.co.uk/tto/multim...0__374392c.jpg


Wouldn't be too happy flying with that happening under my feet.

I would be quite happy with that.
The chance of dying in a plane is
far less likely then dying in your home:
http://www.phyast.pitt.edu/~blc/book/chapter8.html
LOSS OF LIFE EXPECTANCY (LLE) DUE TO VARIOUS RISKS
TABLE 1
Activity or risk* LLE (days)
Living in poverty 3500
Being male (vs. female) 2800
Cigarettes (male) 2300
Heart disease* 2100
Being unmarried 2000
....
Occupational accidents 74
....
Airline crashes* 1
Dam failures* 1
Living near nuclear plant 0.4
All electricity nuclear (NRC)* 0.04

Whilst we have reasonable statistics to reassure re the general safety of
flying, I feel that we do not yet have sufficient knowledge of the safety
of Dreamliner 787s. Only in service since October 2011. So anything that
takes a couple of years to surface...

BTW, how long do lappie batteries typically last?

Varys with how they are used.

Seem to remember they start failing in their second year

Thats bull****.

and often get worse over the next two or three years.

The better batterys dont get that bad that quickly.

DreamLiner and Li-ion
 

Fredxx wrote:

They used to have an emergency generator with a propellor strung
underneath but don't know if that is still the case.

Most have an auxiliary engine / generator in the tail. I guess the idea
of a battery was to dispense with this, making the aircraft cheaper and
possibly more aerodynamic.

Not sure what use a propeller is for generating power whilst on the ground.

The propellor driven generator or hydraulic pump (the RAT) is for
emergencies in flight.

http://www.concordeproject.com/photos/rat.jpg

On the ground all airports nowadays insist that the APU must be shut
down and the aircraft supplied with power from ground power units, in
order to reduce the carbon emissions of the airport.

Batteries are not a replacement for the APU, batteries are required on
all aircraft even if there is an APU. You need something to start
engines and to provide power when all engines, including the APU, are
stopped. Same as you need a battery on a car.

--
Burn Hollywood burn, burn down to the ground

DreamLiner and Li-ion
 

"Nightjar" wrote in message
...
On 18/01/2013 09:28, Martin Brown wrote:
On 18/01/2013 08:51, Mike Tomlinson wrote:
En el artículo , Dave Plowman (News)
escribió:

So they've just discovered Li-ion can be a fire risk?

Seen the photos of the batteries?

Not really surprising. Li-ion is volatile chemistry and if it gets
slightly maltreated can go into thermal runaway self heating. That is
the price for the energy density vs weight trade-off.

http://www.theregister.co.uk/2013/01...787_batteries/

http://www.thetimes.co.uk/tto/multim...0__374392c.jpg


Wouldn't be too happy flying with that happening under my feet.

The big worry is that on the Dreamliner the electrical systems are
absolutely essential for control of the flight surfaces. There is no
independent hydraulic system although presumable there must be some
manual way of lowering the undercarriage for landing in extremis.

The landing gear system isnt entirely electrical.

Possibly not.

Bet they do.

Corse they do
http://www.smh.com.au/travel/travel-...108-1n4fm.html

The undercarriage is only really essential if you want to be able to take
off again after the landing.

They usually want to be able to do that rather than just write it off.

DreamLiner and Li-ion
 

Andrew Gabriel wrote:
In article ,
"tim....." writes:
Apparently, these batteries are not used to "fly" the plane (presumably that
is done using electricity generated by the engines somehow)

They are only used for power when the plane is on the ground

I heard that comment too, but I find it very hard to believe.
Why would you add that sort of weight to a plane, which it
doesn't use when flying, when planes on the ground are powered
by umbilicals anyway when the engines are off?

I'm guessing someone missed out the "normally". These batteries form an
"uninterruptible" supply in the air, and a guaranteed clean supply on
the ground, charged by the aircraft system in flight, and the ground
supply at the airport.

Hmmm... "The 787 battery is from Japanese manufacturer GS Yuasa and
relies on cobalt oxide (CoO2), which has the highest energy density, but
is also susceptible to “thermal events” (read: fires). And the cells
release oxygen in a fire, meaning it is easy for them to continue
burning." Oops.

Extracted from:-

http://www.wired.com/autopia/2013/01...ire-grounding/



--
Tciao for Now!

John.

DreamLiner and Li-ion
 

On Fri, 18 Jan 2013 16:38:25 +0100, Jo Stein wrote:

On 18.01.2013 15:17, Mike Tomlinson wrote:
En el artÃ*culo , Jo Stein
escribió:

Why do people clap their hands after a landing?

Because they're idiots?

Because they are made that way by evolution.

Science is difficult and require a lot of explanation.
You are afraid of heights because you are made by parents that are
afraid of heights.
People not afraid of heights fell down from cliffs and did not leave
children around; their genes are gone.

Why are goats not afraid of heights?
Because goats afraid of heights failed in the struggle for life.
They died from starvation.
You see?

If people were less afraid of height they would have forgotten to clap
their hands after landing.
I never clap my hands when landing because I am busy studying those
passenger that clap their hands.


The only flight I've been on (unless I was P1) where anyone clapped was
after a go-around at Gatwick mid last year - a bit (ok a lot) of wind
shear on late final and TOGA power applied in an expeditious manner
followed by a sedate circuit to make a greaser!

Avpx

--
'They've given us the answers,' he [Carrot] said. 'Perhaps
we can find out what the questions should have been.'
(Feet
of Clay)
16:20:01 up 2 days, 1:46, 6 users, load average: 0.68, 0.99, 1.10

DreamLiner and Li-ion
 

On 18/01/2013 15:49, Nightjar wrote:
On 18/01/2013 11:55, polygonum wrote:
On 18/01/2013 11:17, Nightjar wrote:


Possibly not. The undercarriage is only really essential if you want to
be able to take off again after the landing.

Colin Bignell

Or the passengers want their luggage not strewn across the, I was going
to say "runway", but maybe "wherever they happen to land".

The damage to the aircraft is usually quite minimal

http://www.youtube.com/watch?v=mXWaBrE9_qo

Colin Bignell

Wow! I'd say that took a LOT of skill and nerve.

--
Rod