Originally Posted by
FrequentSLF
I think that understanding that blip will be a key on the investigation, however we (or I) do not even know if the FDR records directly the thumb switch or the signal is processed by the FCC before been transmitted to the FDR.
That particular FDR trace is pretty unambiguous - it's labelled "Manual (Electric) Trim Command" and has three possible states: "Trim Up - Man", "Trim Down - Man" and "No Trim".
If that's not a reference simply to the pickle switch position, one would expect it to be described differently.
There is, of course, a separate FDR trace with the legend "Automatic Trim Command" and states described as "No Trim", "Trim Up - FCC" and "Trim Down - FCC".