Hi All,

I had my Arducopter flight, with AC-3.0.1 firmware.

6 Flight Modes set as:

1. Stabilize  2. Stabilize

3. Loiter       4. Loiter

5. Land        6. Land

I was in Loiter mode and suddenly my copter fell like rain from the air (~7 meters high). I was just testing the modes. Attached is the log file for analysis. (Between 40 - 41, Pitch-Roll-Yaw values. Sudden change, copter FELL DOWN. Damaged my 3DR motor axis permanently, props gone and arm bent nicely. 


Two questions:

1) I am unable to find the reason of the crash. Can someone please help me out for what mode I was in during crash?This is my first time with log analysis although I have gone through

2) My copter swings from one side to the other in Stabilize mode. In Loiter mode it keeps on changing altitude (I had 10 GPS satellites at the time). Can log file help me in finding out reason for this?

I am learning too, the hard way. Looking forward to your inputs. Log file attached.

Flight_Crash at ~40

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  • Developer

    Shyam it seems that you have a couple hardware problem on this frame.

    First, you are hovering at 90 % throttle. This is definitely too high and dangerous. This is certainly the reason of the crash. Do you have an idea why ? It could be an ESC calibration problem.

    You should hover around 50% throttle. 70% is a maximum.

    Second, you have a radio issue. It is not normal that you got two radio failsafe during this flight. You could have a radio hardware problem, or a serious interference between the receiver and an ESC or something else on the frame.

    I encourage you to read the new Wiki and progressively learn as much as you can so that you'll be able to sort out your problems. It's not always easy for beginners specially when there are some hardware issues with their first setup. And use the forum if you need some help.

    It's better to spend time learning and setting up / testing your frame on the ground before to fly again and eventually crash if all problems are not solved.

    If something is wrong at the hardware level on the ground, do not expect that things will be better during flights. Generally it is the opposite.


  • How did you download this log? Are you using a mac?

    There looks to be some radio failsafes - the second one triggers an RTL. There's lots of mode changes between stabilise a loiter - but the log looks to have lots of corruption which is why I suspect you're downloading this on a mac using a VM as thats what I used to get...

This reply was deleted.