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ams6110 | 7 years ago

Interesting, that when they turned the electric trim back on, they only momentarily blipped the switches to trim up, and the stabilizer did move. Then five seconds later MCAS pitched down again and it was over.

Wonder why didn't they trim up more when they turned the electric trim back on. On the surface it appears that was their last chance to salvage the situation.

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rootusrootus|7 years ago

That's what I think is most interesting. Given the position they found themselves in, going against the directive from Boeing to leave the trim cutout for the duration of the flight, means they were desperate to get the trim back up. So why did they not immediately make use of the reenabled electric trim control to counteract MCAS for as long as it took? They had kept the plane flying up until reenabling the electric trim, but that one action pushed it over the edge and could not be reversed? Confusing.

phire|7 years ago

They made two small trim up commands. But looking at the flight data graph, the stablizer on the bearly moves. The motor was probably stugling against the aerodynamic forces too.

Prehaps they didn't think it moved at all and decided they stablizer was jammed. 5 seconds later, MCAS commands down and because that's in the same direction as the aerodynamic forces it moved a lot easier.