Originally Posted by discountinvestigator
[...] If you want to look at equipment failure, then be very careful about the difference between actual position and recorded position data on the FDR. Do they have dual channel readouts? Was there a failure of one thrust lever sensor channel which was unrevealled but occurred earlier in the flight with a second (or logic elimination of its reading) later at RETARD?
This was discussed earlier, see (among others) posts #1216 anbd #1237.
In short: dual sensors, a failure of one sensor is not hidden, but FADEC reverts to failsafe settings. typically TOGA or FLX during takeoff, idle on the ground or with slats extended, MCT otherwise.
So the FDR readout will most likely reflect actual thrust lever setting, although I'm certain the investigation will look into the possibility of an undetected fault here, too.