Extracted from the preliminary accident report:
http://www.havkom.se/assets/reports/SRL-2016_01e.pdf
After one hour and ten minutes of flight, during the pilots approach
briefing, the pilot in command, who was seated in the left seat,
exclaimed a strong expression. Immediately thereafter the aural
warning for autopilot disconnect (named Cavalry Charge) was
activated. The disconnection was also confirmed by FDR data. The
warning sounded continuously during the following 18 seconds.
After the autopilot disengagement FDR data indicates that both left
and right elevators moved towards aircraft nose down position. Left
and right side angle of attack went towards negative values. The
aircraft entered a descent with vertical acceleration values that reached
a negative load corresponding to -1G.
After a few seconds of negative G-load the aircraft's warning system
was activated by a so-called Triple Chime
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followed by an aural
warning (synthetic voice) for low engine oil pressure on both engines.
FDR data shows that the trim to the movable horizontal stabilizer was
activated manually and the trim position went from -0.9 degrees nose
up to 1.7 degrees nose down. An aural signal of the stabilizer trim
movement (Stab trim clacker), signifying a manual input longer than
three seconds, was activated in connection with this. Immediately
thereafter a warning for high bank angle was activated.
After 17 seconds from the start of the event, the maximum speed
(VMO), 315 knots was exceeded. The over speed warning was
activated and the vertical acceleration turned to positive values.
Another 16 seconds later, the first officer transmitted a “MAYDAY”
message that was confirmed by the air traffic control. The indicated
airspeed then exceeded 400 knots and the stabilizer trim was
reactivated and dropped to 0.3 degrees nose down. The Pilot in
Command called "Mach trim"
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after which engine power was
reduced to idle.
During the further event the last valid FDR value shows that the speed
continued to increase up to 508 knots while the vertical acceleration
values were positive, with maximum values of approximately +3G.
FDR data shows that the aircraft's ailerons and spoilerons mainly were
deflected to the left during the event.
Radar data and the accident site position indicate that the track was
changed about 75 degrees to the right during the event.
The crew was active during the entire event. The dialogue between the
pilots consisted mainly of different perceptions regarding turn
directions. They also expressed the need to climb. The aircraft
collided with the ground one minute and twenty seconds after the
initial height loss.
Mr. Snuggles,
The interview in Dubai had this comment in it: (please make allowance for google translate) I do not see any such reference in the preliminary report.
Eleonor Norgren: There are no ready answers. But the crew regarade that something was not as it should, and coupled the autopilot. The process must have been under a minute and a half.