Maiden flight of second hand purchase #2! Errors

rabidhyena · Feb 1, 2020

Anyone any good with the flight logs?
This is my second one I have purchased. All good in the first flight and then it shows compass error and starts tilting and going off with the wind.
Is this a duff one I have purchased?
Many thanks

sar104 · Feb 1, 2020

That's an interesting one. Some compass errors at the start which went away. Then the flight seemed fine. The photo taken at 135 seconds clearly shows that the IMU yaw value was correct to within a few degrees at that time. Then it all went bad at 300 seconds:

This really needs the mobile device (or aircraft) DAT file ending FLY105.DAT to look at the raw sensor data.

Flight log retrieval and analysis guide

rabidhyena · Feb 1, 2020

Hmmm
Is this another one that is going to have to go back to ebay :O(

sar104 · Feb 1, 2020

rabidhyena said:
Hmmm
Is this another one that is going to have to go back to ebay :O(

The yaw error isn't periodic with rotation, and so it looks to me like an IMU rate gyro issue based on the DAT file data - notice how the red trace (integrated z-axis rate gyro) diverges considerably from the magnetic data at around 300 s. I'd try an IMU calibration.