PPRuNe Forums - View Single Post - Boeing 737 Max Recertification Testing - Finally.
Old 31st Dec 2020, 07:36
  #596 (permalink)  
safetypee
 
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Less Hair, by all means think 'what if', but do not invent issues (although technically correct) which could confuse an unwary pilot at the time of a surprising event.
Aspects such as this will (should) have been considered in design, test, and certification.

The following notes are from FAA NPRM; https://www.faa.gov/news/media/attac...-R3-8-3-20.pdf
"The calculated threshold would be a function of the magnitude of the disagreement and the rate of change of the AOA sensor position values."
"More than 10 degrees difference for more than 10 seconds."

There would be greater safety value in questioning crew actions in the event of an alert:-
"AOA DISAGREE alert, that the airplane’s left and right AOA vanes disagree. The checklist informs the flightcrew to accomplish the Airspeed Unreliable checklist."

The memory items for this require 'Pitch Power settings', before evaluating the actual speed indications, i.e before checking standby instrument, or any other alerts.
Also, considering a practical situation of an alert at max cruise altitude - would a pilot pitch up by rote recall of drills? (cf AF 447).
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