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Old 9th Apr 2019, 05:19
  #3679 (permalink)  
gmx
 
Join Date: Nov 2018
Location: Brisbane
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Originally Posted by threemiles
It was cut out by the cutout switches.
Well, it was cut out by the pilots. They had the option to re-trim the aircraft using electric trim before hitting the cutout. I believe this "option" occurred to the crew close to the end when they re-enabled the electric trim but their attempts to re-trim with the column switches was unsuccessful (either through pilot error or malfunction). Had they done this earlier, right before they activated the STAB TRIM CUTOUT, they would have been in a very similar situation to the pre-accident LionAir flight -- a trimmed, stable aircraft, with AP disconnected, and stick shaker going off on PF side.

A couple of points, one made a few posts back.

Firstly, it seems the lessons from the pre-accident LionAir flight and the subsequent accident flight were not learned well enough. As far as we know, the MCAS issue that occurs as a result of PF-side erroneous AoA signal is completely survivable by the crew taking the correct course of action. It seems that the correct course of action wasn't spelled out clearly enough for the ET302 crew, or it was not drummed into them methodically enough. That's a further failing of the airline industry following the initial accident.

Secondly, it has been remarked here on numerous occasions that it is extremely rare for a transport crew to encounter a stick shaker alert. Had the pre-accident LionAir B737 been grounded following that flight, and had the ET302 crew leveled the aircraft before disabling the electric trim and subsequently managed to land, that would have been two flights with PF-side stick shaker active for the duration of those flights. That would suggest a systemic issue, but it does not appear to have received the same attention as the MCAS response.
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