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Old 5th Apr 2019, 03:45
  #3230 (permalink)  
fotoguzzi
 
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[Not a pilot] I note that they had time to communicate and navigate. They set altitudes and headings and communicated their intentions.

Back pressure increases, but that is not graphed, so we will have to wait eighteen months to learn how much they were exerting while they were setting altitudes, headings, etc.

Within five seconds the Captain went from climbing to 32,000 ft to requesting to maintain runway heading. Are the voice and data timestamps compatible?

Summary with points of interest:
takeoff trim 5.6
man/elec trim 4.9 to 5.9 end 5.6
trim via ?? Down from 5.6 to 4.6
auto trim Down from 4.60 to 2.1
man/elec trim Up from 2.1 to 2.4
auto trim Down from 2.4 to 0.4

"At 05:40:28 Manual electric trim in the ANU direction was recorded and the stabilizer reversed moving in the ANU direction and then the trim reached 2.3 units." [One of these ANUs is a typo, no?]

man/elec trim Up 0.4 to 2.3
Cutout

"From 05:40:42 to 05:43:11 (about two and a half minutes), the stabilizer position gradually moved in the AND direction from 2.3 units to 2.1 units." [Approximately, 0.1 units / min.]

"At 05:41:46, the Captain asked the First-Officer if the trim is functional. The First-Officer has replied that the trim was not working and asked if he could try it manually. The Captain told him to try. At 05:41:54, the First-Officer replied that it is not working. At 05:43:04, the Captain asked the First Officer to pitch up together and said that pitch is not enough."

A minute into the two and a half minutes of nose down trim, the Captain asks a reasonable question. Within a span of eight seconds the FO answers that trim is not working, oddly suggests trying manual, gets permission, and says, Nope. What exactly was the Captain asking? What did the FO mean by manual? The nose down was gradual, but the FO only worked on whatever "manual" was for eight seconds.

They worked together on something for seven seconds. Did each have a yoke in one hand and a hand wheel in the other? So, fifteen seconds of trying did not defeat the gradual nose down of 0.2 units in two and a half minutes. Or, another interpretation: eight seconds of cranking in the wrong direction didn't seem to be helping. This interpretation is at odds with the stated "gradual" nose down.

trim Down via ?? from 2.3 to 2.1
Normal [Inferred]
manu/elec trim Up from 2.1 to 2.3
auto trim Down 2.3 to 1.0
trim via ?? 1.1 to 0.8

Last edited by fotoguzzi; 5th Apr 2019 at 21:38. Reason: add possible interpretation; clarification; disclaim
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