PPRuNe Forums - View Single Post - MAX’s Return Delayed by FAA Reevaluation of 737 Safety Procedures
Old 25th Aug 2019, 20:50
  #2036 (permalink)  
Join Date: Mar 2019
Location: On the Ground
Posts: 147
Originally Posted by GlueBall View Post
Without having to THINK, an experienced captain with sufficient manual flying skills would not need to know if MCAS, ordinary runaway stab trim or ambiguous autopilot stab trim inputs were causing the uncommanded nose-down trim. Such trim anomaly at low altitude would automatically trigger a self-preserving INSTINCTIVE response of stopping the trim-in-motion forward moving stabilizer wheel either with his knee, right thigh or right hand and simultaneously ordering the F/O to cut off the electric stab trim switches, or doing that by himself, while simultaneously clicking off the A/P and A/T.
Actually, it's quite a bit more instinctive than that. And it doesn't involve any "Wild Alaska" maneuvering. All the Captain has to do is pull back on the yoke, and forward trim stops. The Control Column Cutout Switches stop "opposing trim inputs." This is true on every manual flight controlled Boeing since the "Dash-80". The pilots FRM for the MAX still says it is true for the MAX, even though it is not. Boeing removed a foundational, instinctive way for the pilot to over-ride undesirable trim trim inputs, put it under the control of some junior level automation programming, and didn't tell anyone.
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