Originally Posted by
DType
Vibration can enable a normally irreversible screw to reverse.
Originally Posted by
Concours77
Absent command, the jackscrew cannot rotate....
Maybe it can, maybe it can't (my money would be on not).
But either way - what is the relevance?
Given the overwhelming evidence implicating the STS/MCAS, why are we throwing Occam's Razor out of the window and postulating an unrelated, independent mechnical failure of the actuation mechanism as a causal factor?
The MAX has the same horizontal stabilizer as the NG, and I'd bet that the actuator/gearbox/jackscrew isn't significantly different either. How many NG loss of pitch trim control incidents have there been in the last 20 years that have been attributable to actuation failure?