Very interesting. The three power-off events show similar initial evolution of pitch, roll and yaw, followed by varied, possibly chaotic, behavior:
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The vertical speed reflects that, with a transition to oscillatory behavior as the aircraft wobbles:
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The blue dotted lines are the model that I posted previously, with a slightly lower drag coefficient than my initial guess (0.025 rather than 0.031), and predict the motion pretty well. The terminal velocity of around 20 m/s (45 mph) is in line with previous data and reports.
I find this very fascinating. Some observations and/or questions.
It seems like the aircraft is tumbling randomly with the predominate motion of head over butt with a fair amount of yaw spin. Can I assume that the rapid changes are sign reversals or number overloads or is it actually flipping over in 100ms or less?
The negative motor speeds seem to indicate auto-rotation but why would it be constant; or is it just a data/math anomaly?
If this is too deep into the weeds let me know. My interest is purely intellectual.