So, what is the problem Ewbanks is talking about and what is his solution? Would it have avoided the Pakistani crash by better alerting the crew to their problem or is this a Boeing-only human factors solution?
The relevant design requirement applicable to the 737 says in part:
Sec. 25.1309 [Equipment, systems, and installations.]
.......
(c) Warning information must be provided to alert the crew to unsafe system operating conditions, and to enable them to take appropriate corrective action. Systems, controls, and associated monitoring and warning means must be designed to minimize crew errors which could create additional hazards.
'Sounds to me that the MCAS system malfunctioning as it did on the two crash airplanes constituted an unsafe system operating condition. The MCAS failing to operate as intended might be an unknown to the pilots? (I don't know, I'm not 737 rated). If the MCAS was malfunctioning, and the pilots did not know it did, or did not know what the correct action would be, would that design requirement have been met?
The 737MAX's delivered to American Airlines were equipped with an optional MCAS failure warning system? (which sounds like it would meet the design requirement). Other airlines received 737MAX's which were not equipped with this optional warning system? Would those airplanes meet the design requirement?