Gretchenfrage,
The quoted paragraph bellow links well with the:
"PostedGraph on Techlog AF 447 Thread #5 Post #1862"
which shows - see the Grayed area - that the Automated (a/c computers controlled) move of the THS from -3 to -13 (to max NU position) took place while the Stall Warning was fully and constantly active.
Originally Posted by
Gretchenfrage
from Safety Concerns
Here are a few comment and questions from a recent meeting:
...
THS
As I understand, the THS was following the PFs inputs right up to full aft, even though the stall warning was active. On Boeings the stabilizer is inhibited to move further aft when stall speed is reached.
Why can an Airbus THS?....
Safety Concerns,
Originally Posted by
Safety Concerns
Your last post confirmed everything I said about analogue pilots and digital a/c
A lot of pilots criticising Airbus are still in analogue mode and wishing for a return to stick shakers and throttle movement. The safety case to go backwards isn't there.
While I think that the
analogue versus digital looks like an interesting wording, or catch, I think that its application in this case is in danger of missing a fundamental point, which is
the lack of a direct information channel between the pilots, in regards to the positioning/moving of the active stick, which matters regardless if the information is processed in an analogue, or digital fashion.
This information channel can take different shapes, including the feedback, or a screen with a 3D animation of the stick, or a 3D animation of the a/c and its control surfaces, etc....
Despite your analogue post please correct me if I am wrong. The Lufthansa Frankfurt incident of reverse stick input saw a PNF take control without witnessing any stick feedback or looking over to see what PF was doing. He was digitally minded and in tune with the aircraft.The sad fact in most of these accidents but not all is that the pilots are not in tune with the a/c.
The first officer was as analogue, as a pilot can be, or a human being is: his visual sensors, internal neural network, memory and analysis/decision functional blocks, as well as the analogue motions actuators worked perfectly. But he was in tune with the situation, and the "a/c", as you state in your last sentence.
There may well be a case for a different training approach but there is NOT a safety case to change the technology.
Training always matters, but this seems to be a different matter, which is quite simple:
The presence of two pilots in the cockpit has a rich set of reasons, one of which is that one pilot can take over, if something is wrong with the controls, or the actions of the other pilot which is being in control.
For this to work as intended, and efficiently, the pilots must be in sync at any moment, and there MUST be a DIRECT information channel in whatever shape, regarding the status of the stick, which is one of the main elements of entering commands/controls.
The guessing or inferring stick status/position/actions INDIRECTLY from other elements is simply IMO bellow the level of general logic behind the Airbus controls.
In abstract, as several levels of indirection, and translation/conversion in passing information is introducing delays, unreliability, and/or loss of information, a direct information transfer is the better solution for that system.