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To: TexasGator
Before the MCAS actuated, they were getting airspeed and autopilot warnings.

I believe that is not true.

From the preliminary report: "At 05:38:44, shortly after liftoff, the left and right recorded AOA values deviated. Left AOA decreased to 11.1° then increased to 35.7° while value of right AOA indicated 14.94°. Then after, the left AOA value reached 74.5° in ¾ seconds while the right AOA reached a maximum value of 15.3°. At this time, the left stick shaker activated and remained active until near the end of the recording.Also, the airspeed, altitude and flight director pitch bar values from the left side noted deviating from the corresponding right side values. The left side values were lower than the right side valuesuntil near the end of the recording."

There is a tolerance between left side and right side WRT airspeed readings and altitude readings. If the disagreement is within tolerance, the warnings are not displayed. The preliminary report never mentions that the "Airspeed Disagree" warning or "Altitude Disagree" warning are ever displayed. The pilots have no reason the execute the Airspeed Disagree checklist.

If you can provide a reference that the Airspeed Disagree or Altitude Disagree warning are displayed, please provide the URL.

IMHO, if either warning had been displayed, the preliminary report would have stated it.

82 posted on 05/04/2019 10:33:50 AM PDT by FtrPilot
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To: FtrPilot

The report mentions several deviations and includes low resolution chart, all of which indicate deviations.

In the case if the Lion Air, AoA deviation was 20 degrees which set off IAS. The Ethiopia plane had a deviation of about 75 degrees which would surely set off the IAS.

Additionally, there was an over-speed alarm on for about two minutes before the crash.


83 posted on 05/04/2019 1:36:00 PM PDT by TexasGator (Z1z)
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