For the Nth times: it is possible to raise eyebrows at Boeing's implementation of the MCAS in the 737 MAX (*) while acknowledging that other factors played key roles in both crashes, and that the Lion Air's report is biaised.
So yes, with competent crews and an adequate safety culture (more to that later), the AOA vane incidents wouldn't probably have turned into disasters.
But Boeing decided that:
- a system whose failure was eventually qualified as 'hazardous' could have a single point of failure (a single AOA vane)
- documentation of the system was minimal (before the 1st crash)
- 737 MAX simulators couldn't adequately replicate MCAS activation
- after the 1st crash, a service bulletin informing airlines was released stating that the MCAS could deflect the tail in increments up to 2.5°, up from the 0.6° told to the FAA in the safety assessment
- MCAS could reset itself after each pilot response to repeatedly pitch the aircraft down
- no provision to deactivate the MCAS system was made other than by completely shutting down the non-malfunctioning electrical trim system
which is not demonstrating a stellar 'safety culture' at their level. Safety Culture was coined in INSAG-1 summary report of Chernobyl's disaster. In this report, and in the INSAG-7 update report, you'll find this sentence: "Nuclear plant designs must be as far as possible invulnerable to operator error and to deliberate violation of safety procedure". So, a safe design must plan for stupidity and incompetence. Not to allow it to thrive, but to shield from it when (not if) it happens.
So yes, some air companies in some part of the world operate under standards not acceptable in the western world, and the rate of accidents demonstrates the difference. However, even if not quite so often, some grave operator errors happen in the western companies too: American Airlines 587, Air France 447, Colgan Air 3407... In some of those crashes, disaster would have been avoided if the crews had just left the plane fly by itself. This was not a solution in the situation leading to both MCAS related crashes.
Instead of fuming at the 'unfair' treatment of poor little Boeing, I personally hope that this will kick the company back on the track towards the safety level it was renowned for. And I also hope that the selection and training of flight crews will improve and not be allowed to deteriorate further.
(*) a previous and different form of MCAS is installed on the KC 46. This system takes input on dual redundant angle of attack sensors; it will disengage with stick input by the pilot.
