Originally Posted by
Lost in Saigon
The consensus is WRONG. Boeing clearly states that electric trim will STOP and even REVERSE unwanted MCAS operation.
Unfortunately, Boeing cannot be relied on as providing full and accurate information. The investigation and further legal actions will have to resolve how the systems actually works. There may be an assumption that electric trim input will override MCAS authority but it is not entirely clear how the system operates with conflicting demands. How the authority is resolved during conflict will have to be resolved fully. There are software, electrical, mechanical and aerodynamic elements to the investigation of the trim system.
Obviously, continuing to rely on conflicting AoA sensors is inherently wrong. MCAS should be disabled automatically if the primary sensor information is known to be unreliable. Boeing were aware of the defect even before the Lion Air incidents, or even at the design stage, but chose not eliminate the defect. The question is why did Boeing act in that way and to what degree they tried to conceal or underplay the issues. The Max MCAS system is poorly designed and inherently dangerous. It has passed through many hands, but for some reason, obvious problems were not addressed or may have been concealed. It is certainly possible that persons in Boeing and in the FAA will be held to account. In those circumstances, there is good reason doubt the accuracy of information that Boeing provides.
While accident investigations generally avoid attributing or proportioning blame, the courts will have to do precisely that. No doubt the pilots could have done better, but were not the primary cause. Boeing are facing some very difficult questions along with the FAA.