Question about the Airbus planes

Mike Ash wrote:
In article ,
Tom Duhamel wrote:

Gliders fly at lower altitudes, at lower speeds, in good weather
conditions...

Airliners fly in high altitude, high speed, low temperature, in
thunderstorms...

Don't think airliners fly higher. It's true that *on average* they do,
and they certainly collect *vastly* more time at FL360 than gliders do,
but gliders *do* collect time there. The current glider altitude record,
set in a composite glider, is over 50,000ft. I don't think low
temperatures or pressures have been seen to do anything bad to the
structure. A fellow did tell me once that a rapid descent can do bad
things to the gelcoat due to the temperature change, but that's a
separate issue, and I don't know if an airliner would even use that sort
of coating.

For speeds, that's really just a matter of increased structural strength
and stiffness, which means using more stuff or different shapes. The
question is how the composites tolerate load, which is well known. They
won't change their characteristics suddenly just because they're moving.

How good is composite when lightning strikes? Doesn't is explode or
something? I don't think it will conduct electricity, does it?

This one is a completely open question to me. No, they don't conduct
electricity as far as I know. In the one famous case of a glider getting
hit by lightning, the lightning traveled along metal control rods. The
rods superheated the air inside the wings, blowing the glider to bits.
Obviously this is not a desirable outcome for an airliner carrying 300
people and no parachutes. I can only assume that the smart engineers
working on this stuff have figured out a way to stop this from
happening, but I have no idea at all what that way would be.


Embedded conductive layers.

http://www.lightningtech.com/d~ta/faq1.html

--
Jim Pennino

Remove .spam.sux to reply.

Tom Duhamel wrote:
How good is composite when lightning strikes?

The following article titled "Building the 787: When lightning strikes"
may provide some background:

http://seattletimes.nwsource.com/htm..._boeing05.html

Doesn't is explode or something?

Probably depends on its electrical conductivity, which in turn depends
on the composition and construction of the fiber. (With enough current
you can even explode a conductor; something of interest to scientists
studying plasmas - and people who like to blow things up:

http://tesladownunder.com/Pulse_Power.htm
http://etd.caltech.edu/etd/available...022006-104759/
http://www.plasmacenter.cornell.edu/ExplodingWires.html )

I don't think it will conduct electricity, does it?

Depends on the composite. If it is carbon fiber, then it can be made to
conduct electricity:

"The fiber also finds use in filtration of high-temperature gasses, as
an electrode with high surface area and impeccable corrosion resistance,
and as an anti-static component." From:
http://en.wikipedia.org/wiki/Carbon_fiber

In article ,
says...
Tom Duhamel wrote:
How good is composite when lightning strikes?

The following article titled "Building the 787: When lightning strikes"
may provide some background:

http://seattletimes.nwsource.com/htm..._boeing05.html

Doesn't is explode or something?

Probably depends on its electrical conductivity, which in turn depends
on the composition and construction of the fiber. (With enough current
you can even explode a conductor; something of interest to scientists
studying plasmas - and people who like to blow things up:

http://tesladownunder.com/Pulse_Power.htm
http://etd.caltech.edu/etd/available...022006-104759/
http://www.plasmacenter.cornell.edu/ExplodingWires.html )

I don't think it will conduct electricity, does it?

Depends on the composite. If it is carbon fiber, then it can be made to
conduct electricity:

"The fiber also finds use in filtration of high-temperature gasses, as
an electrode with high surface area and impeccable corrosion resistance,
and as an anti-static component." From:
http://en.wikipedia.org/wiki/Carbon_fiber

Humans seem to conduct quite well, check out this Indian (meeting his
maker) on top of a train. Warning, some might find it a bit graphic, so
don't watch it...

http://www.liveleak.com/view?i=fc0_1243424473

--
Duncan

In article ,
wrote:

How good is composite when lightning strikes? Doesn't is explode or
something? I don't think it will conduct electricity, does it?

This one is a completely open question to me. No, they don't conduct
electricity as far as I know. In the one famous case of a glider getting
hit by lightning, the lightning traveled along metal control rods. The
rods superheated the air inside the wings, blowing the glider to bits.
Obviously this is not a desirable outcome for an airliner carrying 300
people and no parachutes. I can only assume that the smart engineers
working on this stuff have figured out a way to stop this from
happening, but I have no idea at all what that way would be.

Embedded conductive layers.

http://www.lightningtech.com/d~ta/faq1.html

Cool stuff. Thanks!

--
Mike Ash
Radio Free Earth
Broadcasting from our climate-controlled studios deep inside the Moon

On Jun 23, 9:39*am, Tom Duhamel wrote:

Gliders fly at lower altitudes, at lower speeds, in good weather
conditions...

Up until you start flying in wave and get intimate with rotor.
And they (generally) have to be rigged every time you want to go
flying and there are some rough handlers out there !

george wrote:

Gliders fly at lower altitudes, at lower speeds, in good weather
conditions...

Up until you start flying in wave and get intimate with rotor.

Or within a cumulus congestus.

But agreed, they don't have a pressurized cabin and are usually stored
in shelter.

Dave Doe wrote:
Humans seem to conduct quite well, check out this Indian (meeting his
maker) on top of a train. Warning, some might find it a bit graphic, so
don't watch it...

http://www.liveleak.com/view?i=fc0_1243424473


On the contrary, it's actually because we don't conduct electricity well
that we suffer from it. Since we resist current, we burn (not mentioning
the effect on some of our organs).

Nice video, but not to be shown to children!

wrote:
Embedded conductive layers.

http://www.lightningtech.com/d~ta/faq1.html


Really good article. Summed up some of my interrogations. Thanks for the
link, Jim