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Old 9th Apr 2019, 11:05
  #3727 (permalink)  
threemiles
 
Join Date: Jul 2005
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The cutout switch function was changed with the 737MAX from all prior 737 models. The legacy switch combination was one switch to cutout electric trim altogether, the other to cutout the autopilot trim commands. MCAS and Speed Trim System are both commands from the “autopilot”. With the legacy switch configuration, the flight crew can disable the autopilot commands and retain electric trim. With the 737MAX, the flight crew lose both electric trim and autopilot trim with the cutout switch.

The Flight Standardization Board (FSB) took notice of the nomenclature change of the cutout switches but did not make any mention of the difference in responding to autopilot stab trim runaway. On the 737NG, the flight crew retain electric trim; on the 737MAX the flight crew must use manual trim. It turns out, this is a significant difference in pilot workload and pilot capacity to fly the airplane.
Was this taught in the difference powerpoint "training"?
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