So it looks like the FAA is going to review and approve the software updates the Boeing is putting out soon, but it appears the AoA sensor that is used by the MCAS system had been reported as malfunctioning more than 200 times previously to the FAA.
One of the problems with the MCAS software investigation found was the Boeing software replied on only one of the AoA sensors to make it's decision on whether to nose down as a break from the triple redundancy typical for flight control systems. Hopefully they fix this in the update.
Quote:
The device linked to the Boeing 737 Max software that has been scrutinized after two deadly crashes was previously flagged in more than 200 incident reports submitted to the Federal Aviation Administration, but Boeing did not flight test a scenario in which it malfunctioned, CNN has learned.
The angle-of-attack (AOA) sensor, as it's known, sends data to a 737 Max software system that pushes the nose of the aircraft down if it senses an imminent stall. That software, triggered by erroneous data from AOA sensors, is believed to have played a role in crashes of Lion Air and Ethiopian Airlines jets.
Former Boeing engineers and aviation analysts interviewed by CNN have criticized Boeing's original software design for relying on data from a single AOA sensor, claiming that those devices are vulnerable to defects.
FAA data analyzed by CNN supports that assessment.
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https://www.cnn.com/2019/04/30/polit...faa/index.html