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Old 3rd Sep 2007, 13:30
  #2019 (permalink)  
ChristiaanJ
 
Join Date: Jan 2005
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GMDS,
Come on ChristiaanJ, we're not as naive as that. Nobody requested a exact feedback of the actual thrust.
Not exactly, but several posts did equate TL position with actual thrust rather than commanded thrust, to the extent that in a reply somebody had to point out that the TL wouldn't budge even if the engine flamed out.

The request, relating to this incident, would be more of a feedback of the intended command, i.e. "it wants to increase thrust" as opposed to "it wants to retard thrust".
My issue was with the word "feedback", since strictly speaking there is (or should be) none. The pilot positions the TL to set a thrust demand, the TL position is converted to an electrical signal and sent to the ECU (or FADEC or whatever), and the latter controls the fuel flow to meet this demand asap. At no time is there a feedback.

Having the autothrottle move the TLs mechanically actually simplifies the system slightly, since the command to the ECU always comes from only one source: the TL position sensors.
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