Originally Posted by
Uplinker
That is certainly a step forwards. There are some minor things I would say or ask PM on a normal line sector, that might be deemed stupid questions, so I don't do that in the Sim. And likewise, there are minor things I would normally suggest or remind PF of that I don't in the Sim. Why? So I don't risk showing myself or the other pilot up in front of the TRE while we are being assessed. Daft, I know but that's how it goes.
Two genuine questions for B777 pilots to help my understanding of this incident and the one where the autopilot was accidentally engaged on the ground:
What is the annunciation that the aircraft is in altitude capturing phase, e.g. within 200' or whatever of the selected Alt, (like ALT* on Airbus)? Would this annunciation be displayed on the ground if that mode was accidentally selected?
Secondly, do B777 SOPs tell you to read out loud and confirm that the flight mode annunciations, i.e. selected modes, including autopilot status, are correct before take-off?
Modes are displayed across the top of the PFDs, 3 primary annunciations.
SPEED MODES | ROLL/LATERAL MODES | PITCH MODES
To set up preflight, the FDs are both switched off (should already be...) and the first FD selected on should set the FD to the take-off configuration. On selecting the first FD ON, the mode should read
BLANK | [ TOGA ] | [ TOGA ] (in green).
( where [. ] denotes a highlight of the mode change).
The modes as they have been engaged will be boxed.
If the lateral or vertical modes are armed, they will display under the respective lateral and vertical.
When a mode changes, it is surrounded by a green box for 10 seconds to highlight the change, Boeing has used that since the introduction of EFIS on the B757 and B767.
The MCP selected ALTITUDE will be in magenta above the ALT tape on the PFD RHS.
Triggering TOGA on the Thrust lever switch(es) gives:
[ THR ] or [ THR REF ] | TOGA | TOGA
The pitch bar will rise to approximately 8 degrees ANU. It will start to give valid pitch guidance later in the rotation when the acceleration and target attitude get dynamically calculated. For the incident case, the pitch bar would be at aircraft's pitch initially and would have commanded eventually a pitch down as the aircraft climbed above the captured altitude.
If the first FD is selected ON and the MCP altitude is at or near the aircraft's actual height, then it will engage in
BLANK | [ TOGA ] | [ ALT ].
On tapping the TOGA switch, the incident aircraft showed:
[ THR ] or [ THR REF ] | TOGA | ALT
Selecting the window to 4000' as was reported thereafter from 00000 will not change the pitch mode, it has captured ALT at 00000.... to get the system to be correctly set for takeoff required the arduous task of setting the MCP altitude to an altitude above current altitude, and cycling the FD(s) OFF and then one at least back ON.
p 3.4 of FCTM:
"However, do not follow F/D commands until after liftoff"
p3.8
Rotation and Liftoff - All Engines
...
"Note: The flight director pitch command is not used for rotation". ...
Systems, particularly close-coupled and highly regulated systems degrade over time as a natural phenomenon. The internal selection processes and management suffer what can be considered a genetic defect from repetitive subsets of practices, policy and procedures that tend to drive the system towards the vortex of the drain. internal audit functions exacerbate the devolution as much as they guard against that, as they also result in box-ticking subsets of checklists that become pavlovian style learned responses, which skews the fundamentals that the system may have been established to achieve. One can presume that the regulator provides external guidance towards restoring the full function of a program, they do not, regulators have more interest in compliance than the effect of a vise-like grip around a program that naturally has human variability within it. External critical review is occasionally a good thing and is often a shock to management assumptions of goodness, where critical observation is accepted. This is not IOSA/USOAP or similar it is a critical review of intent, policy, practice and outcomes to determine where risk is developing within otherwise shiny and polished systems that pass with ease audit checklists, yet suffer apparently inexplicable random Disney ride events apparently out of the blue. The pilots in this case undoubtedly passed all requisite checks and standards yet, golly.
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Below is a solution for the airlines that find this too arduous or have a system that has reached paradoxical outcomes such as this and G/As with the belly on the ground. etc. The device below avoids crews having a fixation on magenta lines while planet earth passes them by. Good SA is desirable still however, most of these guys and girls would make great MiG 21 pilots.
