Boeing 737 Max Recertification Testing - Finally.

[MechEngr]

"(2) Be readily and easily detectable and intelligible by the flightcrew under all foreseeable operating conditions, including conditions where multiple alerts are provided."

All three flight crews detected the increased yoke force - and they detected the stick shaker falsely indicating a stall. In human factors nothing is better than tactile feedback to the controls in the hands of the operator.

Still, that's the sort of requirement I was referring to with:

"They don't have any obligation to evaluate every system to ensure it is fail safe; just wash their hands of the results and blame the maker for not accomplishing that all-encompassing task."

Is there a requirement to never make a false warning and never report a false measurement? That's the initiator for the MCAS problem.

Edit: Now I wonder where the warnings for false warnings should be presented.