Originally Posted by
CONF iture
Perpignan told a different story as the USE MAN PITCH TRIM FLAG was initially displayed but disappeared when the flight switched into Abnormal Attitudes Law.
Dani, what is that FCOM reference that could explain I was not able to get a forward autotrim ?
Did it disappear by law change or just get pushed out of view by other ecam messages ? Same effect, different reason. [I have vague recollection it was the latter, but could be wrong].
FCOM reference - section on abnormal attitude flight law. But you know that
The real issue is how you went into that law in sim, but DW didn't and 447 didn't.
Based on what I've read:
- 447 stayed in Alt2 because triple ADR failure meant it wouldn't switch based on airdata conditions (and g-load conditions weren't breached).
- Your sim went into abnormal law based on AOA following dual (not triple) ADR fail
- DW sim again not triple ADR failure, but I'm not sure AOA got high enough to trigger abnormal law from what he's written.
Now, can anyone provide FCOM reference for the triple adr fail caveat on abnormal law entry conditions.... I don't think it's in there.
And yes, not having "use man pitch trim" displayed in abnormal law is not logical to me either. In fact, I'm not sure why abnormal law is there at all - can't see why not use direct law for this purpose (abnormal attitude recovery). What extra authority does abnormal law give over direct ?