[QUOTE=MemberBerry;10506346]I just noticed one more thing about the FDR traces of the trim commands. MCAS trim commands show up in the trace even when the cutout switches are used. But that command doesn't reach the motor, and the stabilizer angle remains the same. This suggests the automatic trim commands are sent to the FDR to be logged directly by the FCC, and are not measured somewhere between the cutout switches and the motor, because if they did they wouldn't show in the FDR trace.
[/QUOTE]
This raises another important question...why the MCAS command is active with a cutout? The cutoff signal is transmitted to the FCC (labelled B) on drawing 27-41. The only answer that makes sense is a programming error that does not disable FCC commands when in cutout, it is 101 coding to interlock the code with the cutputs, including disabling interrupts relevant to such function, and we go back to a other question that is still unanswered, why there is the of PRI and B/U cutout? a back of a switch, that is already available as a CB, and if a back up was needed why not on the NG?
[QUOTE=MemberBerry;10506346]I]
Unfortunately I wasn't able a lot of information about that motor, except this document, previously referenced in the initial Ethiopian thread:
http://www.eaton.eu/ecm/idcplg?IdcSe...me=PCT_3401314
It has information about some circuit board fixes for the two versions of the motor used on the NG. That issue didn't affect the MAX version of the motor according to the document. According to that document the part number for the motor used on the MAX is 6355D0001-01, but unfortunately I haven't been able to find any schematics for it.
In any case, that "motor" is not just some dumb piece of hardware, since the issue fixed for the two NG versions is "Solder joint fatigue of the memory chip". A dumb motor wouldn't have a memory chip. It's quite likely the motor is designed to communicate with the FDR, so it's possible the pilot trim commands are logged to the FDR by the motor.
/[QUOTE]
The controller drawings are basically useless, is that the quality of documentation provided to maintenace?
BTW does anybody knows what type of signals are transmitted to the controller? My guess that are analogue signals elaborated by the main trim enable speed and direction and AP trim enable speed and direction boxes in 27-41