> On the 737NG 3 pitot tubes are pilot, co-pilot and the elevator control feel input. They aren't averaged, voted upon or compared in any way.
You're mistaken. To quote Boeing themselves:
> The most modern systems today use an air data inertial reference unit (ADIRU), which incorporates the best information from three pitot and static sources and provides a single set of data to both pilots. An ADIRU receives information from air data modules, which are located close to the pressure sources.
This is used on, at least the Boeing 757, 737 and Airbus A319, A320, A321, A330, & A340.
This got my attention too. For at least 6 minutes, the crew were coping with the problem - the aircraft was holding altitude and speed, if erratically, and they must have been getting the trim back to approximately where it should have been, or else MCAS would have driven the stabilizer to the point where it overrode the elevator authority.
In about the last minute of that recording, the pattern changes: the pilot trim inputs decreased and became much shorter, and the stick forces changed from going up and down to a sustained, high, back-force.
The article says that near the end, the captain handed over control to the 1st officer so he could look for answers. I am speculating wildly here, but could that coincide with the change in the pattern of the pilot's responses? Could it be that the 1st officer did not attempt to re-trim, or did not do it completely? Did he try to trim manually, but perhaps could not because of the load on the stabilizer? [1]. IIRC, according to Dominic Gates, it would only take two cycles of MCAS intervention until the stabilizer had reached a point where full nose-up elevator could not keep the airplane level.
The chart was published in one of Dominic Gates' Seattle Times articles, but I am not in a position to find it right now...
