Hexacopter crashed at RTL

Hello. Today during flight when i switched from Althold to RTL copter flipped back and then fallen from 60m. Is there anyone can look at my logs and tell me why this happened? Before it was flying normally and RTL worked fine.
FC Matek F405 Std



@rcturgay you forgot to share the log to “anyone
with the link”

Your log ends midair about one second after RTL.
There is no log of VCC - which I find strange.
Did you provide proper 5V power to the flight controller, from at least two 5v sources?
To me - this looks like a power loss to the flight controller.

i provide 5v with matek bec circuit. there is no another 5v source. i get 10v from Tmotor esc and matek bec circuit gives 5v to FC

well, you can test whatever FC can failover between the sources, and work fine of each of them.
your POWR.Vcc log did not log any voltage - which is not normal (unless it’s a feature that FC Matek F405 Std miss)

It is normal. None of these types of boards have Vcc available.Matek, HolyBro Kakute, Omnibus…

I agree with you that the board most likely lost power. Vibration levels are high with a steady rate of clipping events perhaps something shook loose or failed as a result.

Flying on default parameters isn’t the best plan. Check Mission Planner Setup>Mandatory Hardware>Initial Parameter Setup.

@dkemxr - wow - those manufacturers saved the cost of two resistors and one AD capable I/O. That’s kind of impressive in a sad way.
edit: now I see that the controller’s main design goal was size.

Size and cost. Some of these boards can be had for ~$35. Well, maybe not anymore but under $50 anyway.

i tried that and copter was shaking insanely and any settings didnt work. i couldnt tune copter and then i reflashed fc again.

these boards are not reliable you mean?

No, not at all what I mean. I have Matek, Holybro and Omnibus boards in models and they all perform well. The Matek boards are my go-to for new models. I wouldn’t bother with an F4, or even an F7 for that matter. Matek has 3 versions/sizes of the H743.

Then I would guess you missed something.

Matek H743 Slim version is my favourite and i have already used it but because of high price this time i tried to use f405 std and result is little bit doubtful for me.

You should still be able to tune it to fly well. You will have to reduce your vibe levels for sure.