Originally Posted by bearfoil
So if from ACARS the a/p dropped by command from (Computer) ADIRU disagree, then I can't imagine why auto would be allowed to re enter the room even if invited.
Initially flight controls revert to ALTN law due to significant differences between all airspeed sources, AP and A/THR are lost, but if later on 2 airspeed sources become similar while still erroneous, FD bars will reappear and AP and A/THR can be re-engaged. However, ALTN law is latched due to the initial ADR disagreement.
Originally Posted by HN39
Wouldn't the AP adjust its command before it results in an uncontrollable attitude?
Although some protections are still available, PITCH ATTITUDE is not one of them ...
I also think that if flight controls move with the amplitude adapted to low speed but the real airspeed is nowhere close to that, it can be very messy as
henra put it.
Originally Posted by GerardC
You are right, we ALL take whatever weather deviation is needed, AND (preferably before deviating...) we send a message (HF or CPDLC) : "request deviation up to XX Nm due to weather".
Do not forget these routes are not as crowded as the NAT OTS area : after dozens of SA crossings (before and after AF 447 crash), I can't remember of much (if any) "deviation" chat on 123,45 (or 121,5).
On a 330 in the NAT OTS, weather deviations are pretty rare I must say. How commun is it over the SA ?
Originally Posted by Shadoko
Is the AP going back automaticly if the a/c "think" the speed indications are right back?
Whatever the circumstances, the only option to engage one of the APs is to manually select it. In this scenario, you would have to re-select it as well.