Need help analyzing Litchi log

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Hi, I was flying at a job site a couple days ago and had a crash. I was initially using DroneDeploy with no issues. I then began to take video with Litchi and suddenly lost contact with the drone. I believe it was only 369 feet away and 129.6 feet in altitude when I lost contact. I was able to recover the drone (P4P). It was still powered on, upside down, with the gimbal and one landing gear snapped off. It was communicating with the RC again though. It was giving a message that the aircraft was at too great an angle to take off (or something like that).

I've uploaded the log at: DJI Flight Log Viewer - PhantomHelp.com

I've ordered some replacement parts, but am wondering if this would be covered under warranty. DJI seemed like they would not cover it when I spoke with them on the phone. They claimed it was due to weather conditions, which I do not believe to be the case.

Any assistance would be greatly appreciated.

Thanks
 
am wondering if this would be covered under warranty.
DJI seemed like they would not cover it when I spoke with them on the phone. They claimed it was due to weather conditions, which I do not believe to be the case.
DJI phone people aren't always a reliable information source.
Is there something more to the story that gave them the idea that weather had any effect?
There's nothing in the data to suggest that.
The Phantom was stable in the air and then it was on the ground.
Weather doesn't stop the propulsion system and a Phantom is able to resist a lot of weather effects.
I'd open a case with DJI to see what the engineers say.
Start by talking to their online help people and send the Phantom in for analysis.
 
Thanks, no there was nothing more to the story. He just kept repeating that they wouldn't cover it because it was weather related. I corrected him a few times and was finally told to go to their website.

I appreciate you looking into it.
 
Sorry to hear about your crash. Probably just a coincidence but mine crashed the same as yours a few days ago too using litchi and also no indication as to why. Did you get a compass error on screen before the crash by any chance ?
 
Looking at this log, I am wondering what exactly was your controller input when you lost the video feed? Did you inadvertantly pull down on the left stick? Was it in plain sight of where you were standing? It lost forward speed as it lost video... 15 seconds later it was a stationary object at 0 ft. alt.
What happened.png
 
Just a quick look a the data shows nothing conclusive. Just taking a wag, you either (A) Lost a prop (B) Hit something at the point of initial signal loss or (C) Some sort of mechanical failure. Right at the point of signal loss you had just completed a climb, then gave the AC a really hard roll command. Signal was lost at that point. There is no way to verify anything I said without the .dat file from the AC itself. Upload that if possible.


RC INPUT RESPONSE.png
 
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Sorry to hear about your crash. Probably just a coincidence but mine crashed the same as yours a few days ago too using litchi and also no indication as to why. Did you get a compass error on screen before the crash by any chance ?


I think I did get a compass error earlier when I started that day. I'll have to check the logs. I seem to remember that though and after I re-calibrated the compass the error went away and everything appeared to be fine.
 
This was abrupt power failure at 38.8 seconds - either a board connection failure or a battery disconnect - most likely the latter since it appears that it rebooted when it crashed. The .DAT files (there should be 2 if there was a reboot) will confirm either way.
 
Thanks. I'm trying to figure out the dat files now. It was still powered of when I retrieved it (though upside down and in several pieces), so the battery was still in and supplying power. A board connection failure certainly sounds possible. This is the first crash or even hard landing with this drone, but that might make sense.

There seem to be 6 files for that afternoon, though DJI Assistant is displaying "Save To Local (9)" when I add them all. It keeps getting almost done and then losing the connection...which perhaps also points to some kind of connection failure. I'll keep trying to get them posted or look for another way.
 
I've uploaded a dat file to dropbox. I wasn't sure which to use from that afternoon, so there are a few there.
Dropbox - DJI_ASSISTANT_EXPORT_FILE_2018-03-04_02-59-38.DAT

OK - the flight file was DAT360, and it shows power interrupted at offset time 41.875 s. After the crash it did reboot with DAT361. There is no way to determine the cause of the interrupt but, since it rebooted after the crash, a bad battery connection seems most likely.

DAT360_01.png
 
Wow this is really interesting. I’m not hyjacking the thread but when I get my results back from DJI I will also post here to see if reelHIghMedia has the same results. Just seems a bit too much of a coincidence as we both lost our drones roughly the same day, both got compass error, both used litchi and both just dropped out of the sky and yet both don’t have any indication from the DAT files to explain. Maybe a mismatch bug with the firmware of the drone and the software of litchi perhaps.? Pure speculation of course as I am sure many more would have fallen out the sky but just to much of a coincidence and really puzzling. Really hope ReelHIghMedia gets this resolved soon tho
 
I sure hope it's not Litchi.....
 
Wow this is really interesting. I’m not hyjacking the thread but when I get my results back from DJI I will also post here to see if reelHIghMedia has the same results. Just seems a bit too much of a coincidence as we both lost our drones roughly the same day, both got compass error, both used litchi and both just dropped out of the sky and yet both don’t have any indication from the DAT files to explain. Maybe a mismatch bug with the firmware of the drone and the software of litchi perhaps.? Pure speculation of course as I am sure many more would have fallen out the sky but just to much of a coincidence and really puzzling. Really hope ReelHIghMedia gets this resolved soon tho

I don't think it has anything to do with the software or firmware - these are physical power interrupts. In past events they have been caused either by an incorrectly seated battery becoming dislodged or by solder joints on the main board power connection failing. The former seems to be more common than the latter.
 
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OK - the flight file was DAT360, and it shows power interrupted at offset time 41.875 s. After the crash it did reboot with DAT361. There is no way to determine the cause of the interrupt but, since it rebooted after the crash, a bad battery connection seems most likely.

View attachment 95842
This one also exhibits that the .DAT file wasn't allowed to close properly because of the abrupt power loss or crash. Just like
Mystery Crash P4 flewn with Litschi
which was also a P4 Pro

upload_2018-3-4_8-19-26.png
 
This time I used 3.2.0, which is presumably why I didn't see the additional spurious data?
Yes, that would be my bad:). The "feature" that allows the spurious data to be shown has been in and out of DatCon a couple of times. It's nice to have, but, it can cause people to think DatCon is broken. Also, including the feature required fixing some corner cases. Anyway, it will be included in DatCon 3.3.0. I'm thinking better to have it than not.

What did you think of my Excel plot? Sometimes CsvView just doesn't make it.
 
Yes, that would be my bad:). The "feature" that allows the spurious data to be shown has been in and out of DatCon a couple of times. It's nice to have, but, it can cause people to think DatCon is broken. Also, including the feature required fixing some corner cases. Anyway, it will be included in DatCon 3.3.0. I'm thinking better to have it than not.

What did you think of my Excel plot? Sometimes CsvView just doesn't make it.

Excel has some great features, but its graphical output options seem very crude for anything beyond PowerPoint pie charts. It did the job there by displaying the data points though. I really like Igor Pro's output options - you should give it a go.

DAT360_02.png
 
Excel has some great features, but its graphical output options seem very crude for anything beyond PowerPoint pie charts. It did the job there by displaying the data points though. I really like Igor Pro's output options - you should give it a go.

View attachment 95879
You're right I should give it a go. It's probably a case of it's-different-I'm-old-I-don't-want-to.
 
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