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Old 29th Apr 2019, 01:40
  #4541 (permalink)  
737 Driver
Join Date: Apr 2019
Location: USA
Posts: 217

Sorry, fell into pilot speak. Let me translate.

Originally Posted by MurphyWasRight View Post
Turn off the magic, :: The only (documented) way to do this was using the trim cutouts, which they did do.
By "magic", I am referring to the automation. Turn of the Flight Directors, disengage the autopilot and autothrottles. BTW, these are the first steps to the Airspeed Unreliable memory items.

set the pitch, :: the were pulling the whole time with little change in displayed pitch, some oscillations after trim cutout.
If the crew had used the UAS procedures, 10 degrees pitch would have been the appropriate target. Pitch control was effective until the runaway event. The reason the Captain had trouble with pitch control was because 1) he did not actively trim against MCAS, and 2) they cutoff the electric stab trim only after the aircraft was severely out of trim.

set the power, :: Crew left it at takeoff, speed reached and settled at near/just over VMO after trim cutout.
Yes, we are aware. There was no attempt to change the power setting after liftoff. "Set the power" does not mean "Leave the power where it is." It means "SET THE POWER," as in put your hands physically on the power levers and set an appropriate power setting. UAS procedures call for 80% N1, but frankly anything between 80 and 90% would have probably been fine for their conditions as long as they also maintained the proper pitch attitude.

monitor the performance, :: don't know enough to comment, other than noticing speed,
In the domain of instrument flying, there are "control" instruments and "performance" instruments. The basic control instruments are the attitude indicator and the primary power setting instrument (N1 on the 737). The performance instruments are things like airspeed, vertical velocity, altitude, heading. You manipulate the aircraft to establish certain parameters on the control instruments, and then you cross-check the performance instruments to see if the aircraft is reacting as you wish. If the aircraft's performance is not to your satisfaction, then you readjust on the control instruments and re-check the performance instruments. For example, if you wish to climb and the aircraft is not climbing, you increase the pitch and/or power and then you go back and see if you are now climbing (while also keeping an eye on the airspeed).

It also means that if you are OVERSPEEDING THE CRAP OUT OF THE AIRFRAME, you need to do something about that, too.

Hence the mantra, set the pitch (control), set the power (control), monitor the performance.

but they may have not have had confidence in instruments.
This statement really is a bit of a reach.

trim the aircraft, :: One has to believe they were trying once cutout, may have wasted some time if only right switch was selected in mistaken belief that manual electric would still be available as on NG.
The "trim the aircraft" part came way, way before the point that they flew themselves into a corner. Yes, you can put this aircraft into a state that even Buck Rogers couldn't extract it. There was no reason to let MCAS trim as far as it did. The yoke trim switch trumps MCAS every single time. Failure to trim, pure and simple.

move to a safe altitude. . :: require pitch control, although they were gradually climbing until the end.
Pitch control would have been available to the Captain if he had simply used the power of his left thumb to trim the aircraft. He did not. The rest is history.

Last edited by 737 Driver; 29th Apr 2019 at 04:07.
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