Originally Posted by
Turbine70
I think the main point you could be drawing out is that in the incident aircraft, MCAS appears to have provided an unadvertised and intermittent control input of complex algorithmic intensity.
Believe what we are left with is how unadvertised, intermittent and complex was also certified.
I vote with various other posters.
Give it at least two independent inputs, and let it disarm and notify where they disagree.
While superior solutions exist, I cannot see how an inferior solution should be supportable.
It doesn't seem a particularly difficult task although the avionics architecture separation may make it less simple.
- The ADIRUs receive mismatching AoA, instead of reporting 'Unreliable Airspeed' they should just disregard AoA inputs and report 'AoA Mismatch'.
- Then as AoA is mismatched it has to be assumed that MCAS is receiving the incorrect AoA, so
- Disable MCAS,
- Steps 1 - 3 can only be reset by maintenance with weight on wheels
- If MCAS is essential then AOG until AoA reporting is matched and test flown.