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Old 2nd Sep 2007, 19:10
  #1997 (permalink)  
TyroPicard
 
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BOAC said..Do AB pilots perhaps instinctively view the T/Ls as 'selectors' for a given mode?
I don't think so.. you use them as "normal" thrust levers taxying out and in on every flight, on the runway you set a N1/EPR value to stabilise at, then select T/O thrust, move them back at thrust reduction altitude, and finally move them back in the flare. The mode you are interested in is the A/THR mode and that certainly is achieved by T/L movement.. having said that I don't conciously think "I must now disengage autothrust by placing the levers to idle so I can then use reverse thrust" .. I retard them at the appropriate point just like all pilots do then select reverse - modes, what modes????? I think about desired thrust at that point, not modes.
Flight Safety writes..I think it’s interesting that the primary function (or operating mode) of the thrust levers in the A320 is that of the auto thrust selector switch, because this mode is used the majority of the time the A320 is operating.
If you only think of time, true. But if you consider the number of times the T/Ls are moved during one flight .. at least ten "thrust selection" movements, and only one A/THR "mode change" movement (OK two if you count retard to Idle on landing). So I reckon that's at least five to one for thrust control.
I think BOAC has raised a good point, which I think of like this - I am not sure it's a case of "forgetting" No.2 T/L, rather a conscious choice to only move the No.1. This is such an illogical action that I wonder if PF had created an "emergency landing" train of thought when it was merely going to be "demanding". Is it possible to place oneself under enough pressure to perform well, that one prevents clear thought and suppresses years of habituation? I started this train of thought after reading Flight Safety..
Regarding how the mind narrows in an emergency, I explained this in my previous post that as fear rises, the mind moves more toward action oriented "fight or flight" type responses and away from thinking and reasoning type responses. In fear or an emergency, the mind tends to want to act rather than think and reason things out.
This landing was NOT an emergency ... but it became one.
I also disagree with Flight Safety here ..
The primary controls change the attitude and direction of the aircraft and they speed it up or slow it down. Obviously these controls become emergency controls in an emergency.
I don't look on sidestick and thrust levers as emergency controls - you may use them in an emergency, certainly, but not in any significantly different way from normal. Emergency controls are red, often guarded, and need confirmation before moving them!

Tyro
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