CONF iture;
PJ2, I believe SFLY is correct :
25 seconds before the end, the pitch was back in alternate law, but the stabilizer position did not move (?)
There is a possibility that the stabilizer was jammed (?)
There is a possibility that the pilot tried earlier to move it … with no more success than the automatic system (?)
No, SFLY is not correct and the situations you cite, while possible, are unlikely but none of us will know until the final report.
Regarding the Pitch Trim Wheels, the FCOM states that:
Both pitch trim wheels provide mechanical control of the THS and have priority over electrical control.
A pilot action on the pitch trim wheel disconnects the autopilot.
From the FCOM:
ABNORMAL ATTITUDE LAWS
The system applies an abnormal-attitude law in pitch and roll if the aircraft exceeds any of these limits in flight.
– Pitch attitude > 50° nose up or 30° nose down
– Bank angle > 125°
– Angle of attack > 30° or < − 10° (− 15° for A319 and A321)
– Speed > 440 knots or < 60 knots
– Mach > 0.91 or < 0.1
The law in pitch is the alternate law with no protection except load-factor protection and without auto trim.
In roll it is a full-authority direct law with a yaw mechanical.
When the aircraft has recovered from its abnormal attitude, the flight control laws in effect are :
– in pitch : alternate law without protection with autotrim.
– in roll : full authority direct law with yaw alternate law.
There is no reversion to the direct law when the pilot extends the landing gear.
From the Interim Report:
At 15 h 45 min 29 s, landing gear retraction was ordered.
At 15 h 45 min 36 s, the stall warning sounded again.
At 15 h 45 min 40 s, the control law for pitch passed from direct to alternate. The bank angle reached a maximum of 59° to the left and the normal load factor dropped below 0.5 g. TheCaptain’s lateral input is practically at neutral, the longitudinal input is still forwards but is not constantly at the stop. The yaw damper orders were nil and remained so until the end of the flight.
At 15 h 45 min 44 s, the altitude reached a maximum of about 3,800 ft and pitch reached 57° nose up. The bank angle was about 40° to the left.
Although in alternate law 25 seconds before the end of the flight, autotrim (in pitch) may not have been available due to the 57deg pitch attitude at 15h 45m 44s, and loss of autotrim in Abnormal Attitude Laws. As the FCOM states, manual pitch trim is always available and takes priority over electrical control. Manual intervention on the THS was possible at all times, the possibility of the THS being jammed, notwithstanding.
Regarding being able to either view the FMA well enough to see the messages, (dusk, no sun in eyes at high pitch angle, etc), or the notion that the display is somehow "decluttered", I am not aware of such a process where it concerns either messages associated with manual pitch trim - both the amber and the red manual pitch trim messages on the PFD are clear and unmistakable. It would be of some interest to know whether the recorders actually record this message and if so, whether it was present or not.
SC is correct. This was a human error accident on a number of levels including, as I observed, planning and execution similarities to the Toulouse A330 accident.
DC-ATE;
You said:
. . . as I told Smilin_Ed, I think we're beating a 'dead horse' here. History will tell all.....if not covered up. Let these boys play with their toys and hopefully everyone will get where they're going safely.
Cover-up? That's going a bit far isn't it?