[CarrotAndStick]

According to an earlier article, it was moisture in one of the sensors at the rear end of the plane. Atleast that was the *official* explanation.

[TalonDJ]

Atleast that was the *official* explanation.

It is a very believable explanation. My take based on the timeline is that it was a procedural error. They should not have done the sensor calibration before the sensor heater was active.

Based on that dependency I would also speculate that the design was not as robust as it could have been concerning this sensor system. Lack of redundancy and dissimilarity perhaps. I can't be sure without access to stuff that is classified though. I am an Avionics Systems engineer by profession.