Originally Posted by
gums
Salute FCeng !!
Sorry, but my understanding of bad AoA inputs or a combination of sensor inputs to the ADRIU's is that would trigger the a/p disconnect. Would you trust mach to govern elevator trim if it showed 0.3M when at 35,000 feet?
I understand that the MCAS is not supposed to work if A/P engaged. Or is it only that I cannot connect A/P if MCAS trying to kill me?? I also got from the FCOM stuff that A/P would disconnect if we had unreliable/disagree IAS/alt/etcetera. SHeesh. The fault tree I have to run thru when I have all the warnings and bells and whistles and stick shaker in the cockpit is beginning to bug me.
later,
Gums sends...
You have a point there that I need to look into. Namely, will the AOA error that would drive MCAS to erroneously activate if A/P disconnected actually cause A/P to disconnect thus dropping into the situation where MCAS will erroneously activate? If so, single failure during flight with A/P engaged could cause both disengage and MCAS activation. I'll have to do some digging and report back. Maybe others on here know the A/P disconnect answer and can offer their wisdom.
FCeng84