Quadrotor with Pixhawk mission mode crash

Hello all,

We are using a 500 mm quadframe, with 700 Kv motors, PX4 Flight stack (master) in Pixhawk. We have flown two flights:

In the first flight, although we had some aggressive attitude control overall it was an OK flight\ the copter navigated the waypoints in mission mode and only had minor problems while landing because the landing site was lower than home altitude.


Since the copter performed an aggresive attitude in the first mission, we have decreased the Attitude Control Slider from the Tuning part on QGroundControl. During the second flight, the initial takeoff and navigation to waypoint number 1 were kinda OK. When the copter tried to navigate to the second waypoint, it started to fly in circles, as if it was tracking a moving object in point of interest mode.

Then we commanded it to return to land from QGroundControl, thus observing the same circular motion in a tidier manner but the copter was drifting away. By this time it reached approximately to 80 meters of altitude.

So we commanded it to descend to 25 meters from QGroundControl. The altitude actually started to drop, but kept on the same circular motion while flying away (yellow and orange parts). So we forced motor disarm and fortunately crashed the copter into a tree branch then on the ground.


We are suspecting

1- Hardware malfunction from one of the rotors, either related to and ESC or the motor itself.
2- Faulty compass data feed into Pixhawk
3- The tuning that we have changed from the QGroundControl Tuning part.

Also, in cases like ours, which data sets would you recommend us to focus on checking out?