Take off for a while,it suddenly dropped down

I added throttle,but it did not response.what is wrong with it?

In keeping with a fine tradition perpetuated in previous similar posts:
I say it was a pink unicorn landing on top of your craft that caused it to crash


For a problem report, it is better to gives us more details on your configuration, what you where doing and a log. Otherwise, we cannot help you …

@xfacta, your anwser is just insulting … don’t do that anymore …

here is the log file: https://pan.baidu.com/s/18PfGlm-7D0piWs07s8LrVg

here is the log file: https://pan.baidu.com/s/18PfGlm-7D0piWs07s8LrVg

Sorry for being a smart aXX, was trying to be a bit funny like I’d seen on here before, not meant to be insulting.
I’ll gladly check logs and other details using my limited knowledge.

Your motor 3 (RCout 3) is at maximum for nearly all the flight, and your other RCout’s are very high too.
I’d say there is no margin for the flight controller to maintain attitude, it lost control and was unable to regain a stable attitude.
Also you will need to adjust the centre of gravity a bit, balance the craft better.

Please supply frame, motor, prop, battery and ESC details, plus total weight.
The craft seems very under powered.

propeller 15*5,hex-copter,diameter 910mm, hobbywing xrotor 40a,6s 16000mah 25c,total weight 7kg.thanks

What motors?
Did you do the ESC calibration?