I launched from the same usual spot I normally launch from - directly in front of our house. We live in a very grassy area so I launch from the palm of my hand. Once it took off... it was gone. All controls worked with the exception of the down control on the left stick.
Your flight data is showing something unusual and not the usual yaw error situation at all.
I can see why you thought it was 800 feet up (but I doubt it really was).
There's a lot of false data in the flight record.
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The battery data shows one cell impossibly low and two are impossibly high.
It does look like the drone shot up vertically but the altitude data is screwy too.
It hasn't zero-ed at the start and is showing -128 ft.
As it rockets upwards, it's climbing at an indicated 5.7 metres/sec but the Velocity Z data shows numbers between -1 and +1 m/s.
Immediately it had good GPS and recorded a home point, it entered Autoland, but kept shooting upwards.
At 1:51.2, RTH was initiated, but it kept climbing.
It showed no respect for the 500 metre altitude limit and continued upwards although the Flight Mode showed Autoland.
The flight data ends at 6:55.6 with the altitude indicated as 963 metres (3160 feet) !!!
What the actual altitude was is unclear, but it will have been high.
The whole flight is upwards and within a small distance of the launch point.
Changing flight mode or moving the throttle made no difference to the climbing.
The data also indicates that the drone realised it was beyond the height limit.
Looking a litle further into the data, suggests that there are false values for the height indicated by the downward facing sensors.
They start showing zero , jump to 2.3 metresand come down to 1 metre in just a second and stay showing 1 metre for the rest of the flight.
This might be related to the cause of the incident, but there might be more as well.
The throttle was showing when you pulled it down but the drone just ignored it.
The incident was not caused by obstacle avoidance, as the drone kept climbing when the drone faced in different directions.
I'd definitely advise recalibrating the IMU on a lavel surface and seeing if the altitude starts at zero next time.
And make sure there's nothing blocking the downward facing sensors.
osD and ImuCalcs:VelD in the graph ). The height info on the app showed the same ( General:height in the graph ).
