How to analyze a crash?

I got a pretty bad crash today. Everything was flying very nice and suddenly lost altitude and crashed.

The APM board survived, and some motors were very hot, but all of them are gone. 

I can't find any tutorial on how to find evidence on the crash to find out what was the problem... was it a motor? a ESC? an APM bug/crash?

I am attaching the log files to see if someone can give me a walk through on this and find out what could be the problem... meanwhile I get my replacement parts ;)

Thanks guys!



2013-04-29 18-28 191.kmz

2013-04-29 18-28 191.log

2013-04-29 18-28 191.log.gpx

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  • Hello everybody

    i was trying to figure out what hapenned in a crash i had last week, but i´m still not sure of what happened. i was analyzing only the .tlog files. now i connected the apm to the pc, and the logging stopped 3 flights before the one resulting in the crash. i´ll add them here too. the .tlog is from the acrtual crash, from 150m height. i was with a F550 hexa, with original dji motors, so it might be a motor failure. the hexa is heavily loaded, so maybe it was a motor. after the crash, one is not respong, seems like a broken wire.

    the board is an APM2.0, and i glued the memory card in place to guarantee vibration would not remove it from there.

    .logs - 10 logs, but stopped 3 flights before the crash 

    .tlog/.rlog - i added some more, the last one is from the crash. it's on a .rar on the next message, couldn't edit

  • Richard et al,

    I know of no 'hex disease' regarding these problems. The 2.9.x version of code does (did) have an issue with recording Vcc as mentioned upstream. No actual A/D conversion is made by a sample of Vcc but rather indirectly through another method involving the Arduino hardware. It is a code exploit and a valid method of recording Vcc if all the registers and ports are cleared properly.

    If you look at Vcc and see Y axis numbers in the 10's rather than 1000's, the code is not functioning properly. The Y axis value is millivolts so 5000 means 5000 millivolts or 5 volts.

    criro1999's thread has discussion of this HERE.

    If you page through it you get to watch a nifty testing stand one member rigged up.

    He wanted to full-load stress his aircraft and not suffer the results of gravity induced damage.


  • Hi there.

    I have experience with my Quad crash too.

    Please refer here: Link

    The concrete reason why it crash still not clear. But somebody suspect due to I enable RAW data on my log.

    I'm interested to check bug on my quad too. Can somebody advice how to confirm it?

    And can somebody how to check VCC?

    Maybe this is one of the reason of my crash..

  • Log analysis is described HERE.. 

    Your code has the Vcc 'noise' issue that criro1999 has in THIS post.

    Are you flying a Hex?


  • Do you have any telemetry log file (tlog)? This would be also good.

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