AF 447 Thread No. 12

[TC-DCA]

@gums

Wow ! I read a part of the LE problem, that's just amazing.
I'll continue to read the article, that's really interesting !

@vilas

Thanks for these informations !

So as we know, with stick at neutral, ELAC's try to maintain 1g with elevators, until we don't "request" another load factor demand by pushing or pulling the stick, but what I don't really understand is that, if we pull back the stick and then return it to neutral position at 10° for example, the aircraft will maintain it, so what is the purpose of the 1g rule here, the pilot normally demand a stable pitch of 10° "not a stable g" normally ?

That'll be strange for a pilot to see his aircraft pitching up with stick at neutral in a particular condition, like a turbulence, and then, they'll note it to the maintenance log as "uncommanded pitch and altitude changement in cruise/climb/descent", that's what I don't understand, so the aicraft is not really stable and doesn't maintain the pitch ?

Can you explain that complicated rule of Airbus Captain please, with a simple example ?

For another example, here the g limit, if we do a turn of 50 degrees with holding the stick, (or a pitch up to the maximum limit of 30 degrees), the aircraft will be at approximately 2-2.5g, and as positive g limit in clean config. is 2.5g, is that true that we'll nearly or completely loose the pitch during a steep turn for example, to don't exceed the limit imposed by the computers as we are already near 2.5g in a steep turn ?

EDIT: "However the system design would have gradually kept trimming back once the nose was up even with stick neutral to keep 1G."

How is it possible that computers orders nose up with elevators with stick in neutral, and when it does that, normally even in a stall condition, with stick at neutral, the aircraft must maintain the last commanded pitch, so it continue to stall but it normally should t command the g ? True ?