I should point out that the analysis of this event that you guys have been discussing is incorrect.
Firstly, the aircraft never switched to ATTI mode - it was in GPS ATTI (aka P-GPS) throughout the flight until it entered forced landing mode at the end. The satellite count wasn't great (9 - 12) but it was good enough, and GPS health never dropped below 4. It won't switch until it drops to 3.
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Secondly, there were no obviously catastrophic compass issues. If you compare GPS location with the integration of the IMU north and east velocities, then the agreement is good enough. The aircraft behavior does not appear to have been caused by IMU yaw vs. compass yaw discrepancies.
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If you look at the comparison of aircraft speed with stick inputs, it appears that the initial movement of the aircraft was caused by full backwards elevator at 6.5 s. The faster movements after that were due to the attempted CSC.
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On that subject, the CSC failed because the right stick was not pulled fully inwards. Note that if your CSC attempt really was both sticks in and down, then it appears that you were flying in mode 3, with elevator and aileron on the left stick - is that correct?
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The remaining puzzle regarding this flight is the yaw dataset, which shows very strange uncommanded periodic oscillations. That's going to require the mobile device DAT file to diagnose properly.
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In summary, the log suggests that the behavior of the aircraft is largely accounted for by an attempted CSC. However, the compass data are strange and need further evaluation, requiring the mobile device DAT file.