Originally Posted by
ashill
In fact, isn't that a leading candidate for the underlying cause of at least the Lion Air crash to which the Ethiopian Airlines crash has worrisome similarities? The aircraft are different in balance but Boeing added software to make them fly almost exactly the same as a 738 to save airlines crew retraining costs, and the preliminary evidence suggests that software reacted in a catastrophic way to bad sensor data in the Lion Air case. So 7M8 pilots are largely 738 pilots with less retraining than is typical for a new airplane.
I'd argue that pilots reacting in a catastrophic way to software reacting to bad sensor data was also the issue.
Note how the exact same failure mode that caused a TK 737 to crash short of the runway at AMS after a bad radar altimeter triggered logic that retarded the autothrottles to idle was noticed by an AA crew on approach to MIA. The AA crew quickly noticed the uncommanded rollback, disconnected the autopilot, pushed the throttles forward, and hand flew the airplane to a safe and uneventful landing. The TK pilots sat there fat, dumb, and happy
for 90 seconds at idle thrust as their 737 flew them into a field.
Is it bad software design that a negative altitude readout on just one side's RA will trigger autothrottles to retard? Yes. Does that excuse a lack of basic airmanship and watching what your airplane is doing at all times? No.