Originally Posted by
Mr Optimistic
Please stop discussing this: all that needs to be said has been said.
That would depend what you mean by "this" - after all, you yourself were advocating the old "big red button" argument a short time ago, which would arguably have had no effect on this incident at all.
Originally Posted by
RR_NDB
Trimmable Resource Automatically Positioned
Depends on your definition of "Automatic" - it moved because the PF commanded it to move. If he wasn't aware that he was commanding it to move, then that was a fault in his training - not the aircraft, for which plenty of documentation on the functions of autotrim in both Normal and Alternate Law is available even to non-pilots.
The designers made the algorithms. And the a/c' s really (BEA said) worked as designed.
The control laws were designed by the systems engineers rather than the software engineers as a way to abstract the complex operations involved to a more easily-understandable level to non-techies.
The crew (under stress) of AF 447 and TAM 3054 did receive ADEQUATE real time indication on the IMPORTANT (auto) configs, respectively of THS (in an stalled a/c) and eng#2 PWR after touch down (landing)?
Of course - in the case of the trim wheel position indicator in the case of the former and engine power indicators in the case of the latter. The problem is that no-one appeared to have been looking at those indications - understandable in a stress situation, but in this case the design of those systems was no more or less complex than in any other modern aircraft. The trim wheels are in the same place on every other equivalent airliner, as are the engine indications. In the case of the TAM accident, even the old moving thrust lever argument can't be brought up, because whether they move or not the fact is that one of them was clearly in the wrong position. Unfortunately it would appear that neither pilot noticed, presumably because they were (understandably) fixated on speed indications and trying not to run off the end of the runway. This was also cemented when the Turkish crew did not notice the moving thrust levers of their 737 pulling off power.
i am just commenting the danger of auto (pre programmed) functions that apparently don't respect how rich is reality faced by us. And the potentiality (risks) of complex systems to perform as K.I.C.S. mechanisms. Just the opposite intended by the designers.
C. stand for Complex
In the case of AF447, the only automatic function involved was the trim, and that was wholly slaved to the inputs of the flight crew on the sidestick as soon as Alternate Law was latched - at the risk of repeating myself,
If [the PF] wasn't aware that he was commanding it to move, then that was a fault in his training - not the aircraft, for which plenty of documentation on the functions of autotrim in both Normal and Alternate Law is available even to non-pilots..
In the case of TAM, if you only move one thrust lever to idle on a conventional aircraft, the engine controlled by the other thrust lever will continue to produce power just the same as it did in that case. It was likely there was no "confusion" on the part of the crew as to why they were using the old and deprecated method - because at least one of them knew that it stopped the aircraft faster. It was just unfortunate that in adopting that method that they made the same mistake that caused the old method to be deprecated in the first place.
I don't think systems complexity had a great deal to do with either case, notwithstanding the fact that there is no such thing as a "simple" system to control a modern airliner.