@ppoirier In testing our copter with a Pixhawk, PX4FLOW, TFMINI Lidar for altitude, with all GPS parameters turned off(Optical Flow Only), we can take off in Loiter mode and hover relatively well but after a few seconds it kicks out of LOITER mode and we get an EKF variance error and looking at the EKF gages, the horizontal position EKF is high and in the orange.
When taking off in Stabilize and trying to switch modes to POSHOLD or LOITER the flight mode change fails. Altitude seems to be fine? These issues go away when we turn the GPS back on.
Do you have any suggestions or guidance? Any log plots you would like to see?