In one of the flights, the drone crashed right after takeoff.
After analyzing the log I understood that there was a fluctuation in the POWR.Vcc. It fluctuated by more than 0.6 Volts for a few milliseconds.
I would like to understand if that was the only reason for the crash or if is there anything else that I am missing.
Also, I would like to understand how I mitigate this issue from happening in the future.
I believe the problem is a battery connection issue. You can see in this graph that the battery voltage falls into an abyss even though current draw also goes away. You would normally expect battery voltage to drop because there was a large current draw. In fact further on in the log there are two smaller drops in battery voltage but not associated with any current draw - further proof there is a battery connection issue.
A voltage drop of this magnitude would normally be associated with a current of many tens of amps or even hundreds.
The Vcc does drop with the extreme battery voltage drop, but it doesnt stop the flight controller. Logging and everything continues on as normal. In fact during the big voltage drop the flight controller was still trying to command the ESCs to correct for the loss of attitude control. The ESCs and motors had no chance of producing a result since battery voltage was gone.
Maybe supply a couple of pictures of your battery and power wiring.
