Stefan wrote:
FBW system, rather the opposite: The pilot had shut down the computers
surveillance system, because the computer wouldn't have allowed him to
fly his dangerous maneuvre!
No, this was a demo of its computer systems capabilities, they woudln't have
shut it down.
Secondly, the big red button isn't to override the computer, it is the
"override the other pilot" button. (eg: to decide who is controlling the plane
when both pilots are wanking their joystick at the same time)
On airbus planes, because they have a joystick with no feedback, one pilot
really deson't feel what the other pilot is trying to do. And one can override
the other by pressing the button, at which point his joystick takes control.
When it launched its 777, it was Boeing that bragged about its pilots being
able to break the flight enveloppe by pulling really hard on the yoke, and
that was marketed as a big advantage over Airbus cockpits where pilots
couldn't break the limits.
Pulling Gs isn't really the issue, it is preventing a stall. And that is where
the computer is far more accurate than a human and this is where engine thrust
does not follow immediatly a pilot's command (it takes time for engines to
increase or reduce thrust). You can't start to climb as soon as you raise
engine thrust is your speed is so low that you are borderline stall at level flight.
Had this been a Boeing plane, the pilot would have heard an alarm and felt his
yoke vibrate indicating he was about to stall the aircraft, and he then could
either have continued to try to climb and stall (falling down on trees), or
tried to level and pickup speed before climbing, giving the same result as the Airbus.
What is not known about that particular indcident is whether then then current
software of the A320 would have warned the pilot that his command to climb
could not be executed due to stall conditions, or whether the pilot was lost
wondering why the plane didn't respond to his command to climb.
The above would make a big difference if the pilot had not yet applied more
thrust to engines. The stall warning might have triggered an automatic reflex
by the human pilot to increase thrust. On the other hand, the pilot should
have known that at current very slow airspeed, he could not climb out and
would need to increase thrust.
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