"Turkish Airlines says the A/T
"kicked back unexpectedly" and that Boeing "had not
mentioned", in its documentation, a need to disconnect the A/T during the (stall)
"While acknowledging that disengagement of the A/T is not
described in the recovery procedure, the Dutch Safety Board highlights the
problems of incomplete knowledge of the aircraft's interdependent systems. It
points to the crew's suffering from "automation surprise" with
respect to the A/T behaviour - during both the original loss of thrust on
approach and the attempted stall recovery."
But both Turkish Airlines and Dutch Safety board are partially wrong...
As matter of fact, there are 2 procedures regarding stall in the Boeing documentation.
The first one is the Approach to stall recovery, as described in QRH MAN 1.1, and the same procedure, more developed in the FCTM 7.8 to 7.10 (October 31,2008) . In both QRH and FCTM, there is no mention of the A/T that should be disconnected, as stated by Turkish Airlines and the Dutch Safety Board.
But the the second procedure: Recovery from a fully developed stall is explained in FCTM 7.11 (October 31, 2008). In this paragraph, there is a note that states: