Originally Posted by
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No point in going over it all again R Baby but briefly those switches don’t switch off MCAS - they switch off the Stab trim, which MCAS attempts to operate. MCAS can only be disabled by Slats out or and AP on.
My poorly made point was that disconnecting AP/AT and flying manually will not on it’s own get you out of this mess, as it would out of most others. Indeed, leaving the AP engaged would be beneficial in the special case of MCAS rogue operation. Problem is the Speed Disagree situation / Stall warning preventing this.
As recommended by Oldn’ see early threads for more on this and Trim wheel diameter problems.
Manual flying is of course not macho (some commentators are.) It is one of the most satisfying things to do and probably why we became pilots.
Switching off stab trim (Stab Trim Cut Out Switches) prevents any stab trimming and that stopped Version 1 MCAS having any effect. So it may have been running inside the STS subsystems - but it could not do anything to affect the operation of the aircraft. From reports the
updated MCAS will
not repeatedly operate so the main problem of MCAS re-initializing and repeating a ND trim after any electric trim input has been removed in the Max from now on. The initiation of the problem caused by the single point of failure of only using one AoA vane has also been removed by the MCAS being linked to both AoA vanes. In other words the direct MCAS threat has been removed.
So your post should really use the past tense.