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Old 29th Mar 2016, 20:59
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DiamondRider
 
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Originally Posted by donotdespisethesnake
Understood. I take the leaks with a big pinch of salt.

I am wondering what is theoretically possible to determine conclusively whenever the final report is made. Some incidents of dual inputs have been made on "the balance of probability", and not all parties agreed to the conclusions. In the case of AF447, the FDR showed in black and white there were dual (and opposing) inputs, which is possible to see because of FBW controls.

It seems to me that in 737 the control surface deflection can be recorded, but not individual control column movement which would definitively show conflict of elevator command.
The FDAU records parameters for the CAPT and FO control columns. Both force (push/pull) and column deflection, so conflicting inputs will easily be discovered. Parameters for the individual elevators and the aft input torque are also recorded. In addition to this there are also other sensors recorded that could be useful, Neutral Shift Sensor, Mach Trim Actuator and several stabilizer sensors. Investigators should be able to tell what was going on with the pitch control.
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