Boeing 737 Max Software Fixes Due to Lion Air Crash Delayed

[Caygill]

Originally Posted by Ian W

It doesn't seem a particularly difficult task although the avionics architecture separation may make it less simple.

1. The ADIRUs receive mismatching AoA, instead of reporting 'Unreliable Airspeed' they should just disregard AoA inputs and report 'AoA Mismatch'.
2. Then as AoA is mismatched it has to be assumed that MCAS is receiving the incorrect AoA, so
3. Disable MCAS,
4. Steps 1 - 3 can only be reset by maintenance with weight on wheels
5. If MCAS is essential then AOG until AoA reporting is matched and test flown.

I also think using the input from two AoA sensors would allow an almost foolproof foundation. With any understanding of data science, voting out the faulty should not be hard - and if not possible, due to both providing sane enough data, that could lead to a different outcome.

But we need to allow killing MCAS without killing the electrical trims.