Keema's Nan wrote on Tue, 07 May 2019
20:47:41 +0100:
On 7 May 2019, Fred J. McCall wrote
(in ):
Keema's wrote on Tue, 07 May 2019
14:51:34 +0100:
On 7 May 2019, abelard wrote
(in ):
On Mon, 06 May 2019 18:49:45 +0100, Keema's Nan
wrote:
On 6 May 2019, Byker wrote
(in ):
"MM" wrote in message ...
It was announced on this morning's Sky News that a lot more
passengersmight have escaped down the front slides if people had not
stopped tocollect luggage from the overhead lockers.
Could one not make the case that every passenger seen on the tarmac*with
luggage* should be prosecuted for collective manslaughter?
Check out "Airplaneski" (1995) sometime:
https://www.youtube.com/watch?v=Umr6JY6f2fw
Things have improved somewhat, but Aeroflot still has a LONG way to go...
A long way to go to do what?
Emulate the superb safety record of Boeing aircraft?
Any flying metal tube can be struck by lightning.
they are lowering the metal content of the skin...
i'm not sue if that is entirely a good idea
I think that the fuselage would act like a Faraday Cage, but the main
problem
is what the various electrical and electromagnetic fields and brief power
surges will do to the onboard computers - which are in control these days. I
imagine that the results of a lightning strike would be somewhat random on
the aircraft’s electrics.
Why would electronics inside the tube suffer any greater disruption
than, say, people?
Because people are not quite so susceptible to induced charges, being full of
water.
An interesting supposition but not born out by the facts. It takes
100 mA to kill you.
It's a Faraday shield (not a cage in this case)
Thanks for the pedantry.
Thanks for demonstrating you don't care if you get it right or not.
or
it isn't. Electronics probably have their own shielding as well, so
are better protected than the stuff in the seats.
This is not the sort of thing you want at 35000ft, but at least up there the
crew have a few minutes to attempt to gain control and/or re-boot the
computers. This is not a possibility if the aircraft is on its final
approach
at a few thousand feet above the ground.
If you get sufficient 'jolt' to require rebooting the computers I
would expect something to be fried and they won't. However, note that
pretty much all 'fly by wire' aircraft have a manual mode and can be
flown without the computers. You might lose a lot of displays and
such, but they'll still fly.
Presumably you are unaware of the recent 737-Max crash? Not lightning, maybe
- but crew turning the computers off nevertheless.
I'm probably more aware of them than you are. It also has absolutely
zero to do with what's under discussion. The problem wasn't crew
turning the computer off. It was them turning it back on. And they
didn't 'turn the computer off', just by the way.
Here is a timeline for you -
08:38 A sensor on the pilot's side falsely indicates that the plane is close
to stalling, triggering MCAS and pushing down the nose of the plane
08:39-40 The pilots try to counter this by adjusting the angle of stabilisers
on the tail of the plane using electrical switches on their control wheels to
bring the nose back up
08:40 They then disable the electrical system that was powering the software
that pushed the nose down
08:41 The crew then attempt to control the stabilisers manually with wheels -
something difficult to do while travelling at high speed
08:43 When this doesn't work, the pilots turn the electricity back on and
again try to move the stabilisers. However, the automated system engages
again and the plane goes into a dive from which it never recovered
Interesting, but wrong. What that particular crew did was repeatedly
cycle the electronic trim control off and back on, which is what the
procedure called for. Note that this is JUST the electronic trim
control, not the 'electricity'. Adjusting trim manually using the
jackscrew is painful but possible and you hardly need perfect trim to
fly the airplane and flying that way wasn't attempted. At most trim
was set to neutral and then electronic trim was reenabled. Also note
that using the manual switches for electronic trim would disable MCAS
for 5 seconds, so 'nudging' the trim switches every few seconds would
have kept the aircraft trimmed and MCAS out of the loop (but they
didn't know that). The problem was that MCAS had more control
authority than could be overridden by the stick, so when MCAS
activated and threw the nose down it didn't matter if the pilot went
full back on the stick, the aircraft would still be nose down.
The actual issues here are more complicated than the explanation I've
given and infinitely more complicated than your description, but they
have nothing to do with electrical strikes and 'rebooting' computers.
--
"Ignorance is preferable to error, and he is less remote from the
truth who believes nothing than he who believes what is wrong."
-- Thomas Jefferson