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Old 22nd Nov 2018, 17:24
  #1517 (permalink)  
wiedehopf
 
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Originally Posted by climber314
Initial/TO/Climb Stab Trim Value shown is just under 7.5 followed by a period of flux with the value ultimately returning to 5.0 preceding leveling at 5,000 ft. This pre-nosedise value of 5.0 continues, increasing to approximately 6.75 with incremental stepping (upward) throughout the course of the descent to a maximum value of just over 7.5 and subsequently returning to a value of 5.0.
The picture you are describing seems to be from the previous flight.
(See on the x-axis written DPS and CGK would indicate a flight from Denpasar to Jakarta, the accident flight however departed Jakarta)

So you can see the constant up and down after selecting flaps up being produced by manual flight fighting the MCAS system so to speak.

Then they switched off the trim and a couple of minutes later maybe tried to switch it back on and obviously switched it back off with manual trim for the rest of the flight.

Traces as far as i can read from top to bottom are:
BLUE: TRIMUPMANUAL
YELLOW: TRIMDOWNMANUAL (yoke switches would be my guess)

BLUE: PITCHTRIMPOSITION

GREEN: TRIMUPA (A for automatic would be my guess)
VIOLET: TRIMDOWNA

RED: STICKSHAKERLEFT
GREEN: STICKSHAKERRIGHT

RED: CCFORCE_PITCHWSLOCAL
GREEN: CCFORCE_PITCHWSFOREIGN

RED: ANGELOFATTACKINDICATEDL
GREEN: ANGELOFATTACKINDICATEDR

LIGHT GREEN: FLAPS?????POSITION

RED: COMPUTEDAIRSPEEDL
GREEN: COMPUTEDAIRSPEEDR

BLUE: ALTITUDE_101325MB_L

Last edited by wiedehopf; 22nd Nov 2018 at 17:41.
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