3 ms·

Here we are again, this misconception just won't die. In the 737 MAX, the only way to disable auto-trim also disables powered trim (the thumb buttons). As gran

Here we are again, this misconception just won't die. In the 737 MAX, the only way to disable auto-trim also disables powered trim (the thumb buttons). As grand parent says, at a certain step in the sequence it was not physically possible for a pilot to trim the plain back to stability manually. It simply can't be done. In the 737 ng, there was a button to do just that. That would have been useful. And that's even ignoring the fact that all symptoms were very different from those present in a runaway trim situation as described in the manual and learned by the pilots.

SoftTalker 3y ago
The thumb buttons would override MCAS. But then you'd have to disable the trim motors and trim manually (by hand-cranking a wheel). That part was not clearly understood by the pilots, because they were not told about MCAS.
- drtgh 3y ago
  How are pilots expected to disable a malfunctioning MCAS in an emergency, and balance manually by trial and error the aerodynamic extravagances of the angle of attack of such unbalanced aircraft in the middle of procedures? The user of the parent comment is remarking about time. The aircraft can be certified without MCAS? By what I read, MCAS is there for to avoid entering into an aerodynamic stall when the aircraft is approaching a high angle of attack, due it's using larger motors for what classical 737 was designed for. It's balancing an unbalanced aircraft using software to repeatedly adjust the horizontal stabilizer. It is not my field, but I'm not even sure if it should be called to trim, it sounds like a euphemism for what's going on.