Calibrated accelerometers.
When the drone is at rest, the accelerometer reads: x = 0.0g, y = 0.0g, z = 1.0g
When the drone hovering at one point in flight motionless, the accelerometer reads  x = 0.0g, y = 0.0g, z = ~0.9g
The vibrations are not strong, but quite ordinary.
The drone flies stably in fpv mode. The problem manifests itself only in GPS mode, when the readings of the accelerometers are very important. 





Does anyone have black box logs in stationary hover mode, for comparison?

The accelerometer readings are relative. For a hover flight you are not really pushing G's. Try a flip or a roll.

What happens to your quad in GPS rescue mode?

(26-Jul-2021, 01:55 AM)kafie1980 Wrote: What happens to your quad in GPS rescue mode?

The controller thinks the drone is in a falling state and begins to compensate for this by accelerating upward. As a result, it flies into the sky.

Do you have a Barometer onboard for Altitude data?

GPS Altitude data is not very reliable on its own with an error of 10-20 meters or more in the estimated vertical position above Mean Sea Level vs horizontal position accuracy.

(26-Jul-2021, 06:44 AM)kafie1980 Wrote: Do you have a Barometer onboard for Altitude data?

GPS Altitude data is not very reliable on its own with an error of 10-20 meters or more in the estimated vertical position above Mean Sea Level vs horizontal position accuracy.

The barometer is present and works as it should. GPS works fine too. The problem is observed only in the operation of the accelerometer.