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Old 15th Apr 2019, 22:42
  #4068 (permalink)  
737 Driver
 
Join Date: Apr 2019
Location: USA
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I say again....

Originally Posted by ams6110
Just curious, how many would read that slide, take perfunctory note of the change, and move on, and how many would stop short, and start asking "What? What does this change mean? Is this just a labeling change? Can I still cut out the auto trim separately from the manual electric trim? What has changed about the trim operation? Where can I find out more?" and what would be the result of such inquiries made to the company training department/chief pilot?
I posted this yesterday morning, but I think it got buried awaiting moderator approval (hopefully I'll be off probation soon )

Procedurally, it does not matter what the switches do or how they are labeled. You could call the switches "Hank" and "Frank", and it does not matter. From Boeing's perspective, you don't have to know what these switches are connected to. Whether the NG or the MAX, you always cutoff BOTH switches when called for in the NNC.

It wasn't always so on the NG. A while back, the 737NG stab runaway procedure was changed so that BOTH cutout switches are always selected together, and we no longer try to isolate the offending circuit. I was kind of curious why the change, but I was simply told that Boeing thought this was a better to handle runaway trim. The conspiracy theorist in me now says that Boeing did this because they were looking down the road at the MAX certification and were looking for any opportunity to harmonize procedures.
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