Goblin crashed hard in the wind yesterday. I changed nothing as far as tuning, it just went bad very fast as it accelerated up wind.
Not exactly sure what happened, it sounded like a bad tail rotor oscillation, it was all over in about a second.
I had made several flights at these settings (10) and I thought I was about done tuning. It was flying great in auto with rotor RPM at 3200.
I attached the log file if anyone cares to take a look. Strange that the Baro stops at 15 meters, because the Heli defiantly hit the ground in a spectacular way with power on.
I had a look at the logs and it’s not super clear what happened. But what it appears to me, is that your P-gain on the yaw was too high while flying upwind, and an oscillation started. The logs just end, so I think for some reason the Pixhawk shut down. It could have been a voltage spike on the servo rail due to the fast servo movements. Are your servos plugged into the servo rail? And if yes, do you have a zener diode on the rail to prevent voltage spikes?
It is very common for helicopters to need different gain settings on yaw depending on the airspeed. I normally find that I need to cut the P-term in half for flying fast, compared to what it needs to be for hovering. I do notice that your yaw I-term is quite a bit too low. This should be at least 0.100 up to 1.0 typically. Overall your yaw control seemed pretty loose.
The Roll/Pitch control is also not achieving targets very well, have you trimmed the swashplate properly? I notice the trim value for all 3 servos is the same.