Battery Die?

Just looking at the altitude prior to impact it is showing only 43 feet. Is that accurate? If it is, just by looking at street view near the crash site the trees in that area appear to be taller than 40 feet.
Well, looking at the KML file from the phantomhelp site (using google earth) it does look like you're flying quite close to the tree tops rendered (note: google earth height renders are approximations so some may be higher or smaller then rendered).

Also, your second waypoint out in the clearing there looks lower than your original altitude over home-point, it it possible your last waypoint's altitude was set too low?

Certainly looks like your phantom plowed into and/or got caught by a high-reaching branch on the return leg.

mehURy
 

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What sort of converter application would you suggest to best read the uploaded .dat file when using Windows?
There are actually 2 that you need and one optional. The converter and viewer are in the links below. After conversion you can use CSV View or Excel.

DatCon Downloads

CsvView Downloads
 
Certainly looks like your phantom plowed into and/or got caught by a high-reaching branch on the return leg.
If this were the case the logs would have shown an impact. There was none.
 
Hello Fly Dawg,
What sort of converter application would you suggest to best read the uploaded .dat file when using Windows? I see from a google search there are several which may be used to convert to various applications and was curious what you may have found works well.

CsvView/DatCon

Is what I use.

You can use DatCon to pull the raw CSV and analyze it in Excel (or Open Office - Calc), or use CsvView to quickly plot graphs if Excel is too much info for you.
 
If this were the case the logs would have shown an impact. There was none.

Not necessary. The logs saved by the app (DJI Go or Litchi in your case) usually miss the last crucial second or two before end of flight. That's why retrieving DAT files from the aircraft itself is so important.
 
Thanks much, Fly Dawg, spirytus.
Fortunately, I personally haven't found the need to evaluate any such data YET, but certainly appreciate those who have repeatedly taken the time to research the various data offered by the not so fortunate, and post there thoughts and results of there findings openly.
Nice work!
 
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Not necessary. The logs saved by the app (DJI Go or Litchi in your case) usually miss the last crucial second or two before end of flight.
I agree with the .dat, however in every impact instance of every flight I have looked at ( And there are a lot ), there are always extreme deviations in attitude at any impact. The data is transmitted at 10hz. That is more than enough time to see any sort of impact.
 
I agree with the .dat, however in every impact instance of every flight I have looked at ( And there are a lot ), there are always extreme deviations in attitude at any impact. The data is transmitted at 10hz. That is more than enough time to see any sort of impact.

Hmm, true enough, and it's very likely this is another case of sudden voltage drop in the last 200 ~ 500 ms before FC logs stop. Still, data from the aircraft is far less refutable.
 
it's very likely this is another case of sudden voltage drop in the last 200 ~ 500 ms before FC logs stop
Not according to the log's. This is the last second of the flight. There are no deviations whatsoever. It simply stops. But even the .dat file will not tell you much more in a case such as this. But when you have the device logs for the Entire flight, it is still quite useful.

LAST Second.png
 
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Just looking at the altitude prior to impact it is showing only 43 feet. Is that accurate? If it is, just by looking at street view near the crash site the trees in that area appear to be taller than 40 feet.

So that 42 feet means that it was 42 feet above "HOME". Not those trees. Yes those trees are like 80 - 100 feet tall. The last part of the video feed shows that the drone was WELL CLEAR of any and all trees. So yes I am 99% certain this was the fault of the battery disco. I was flying from on top of a hill. Let me say, that is where the drone mission started. If you look at the path of the mission, the drone had passed WELL clear of all trees on the way down. So on its way back it had already cleared the highest trees before it even got to the waypoint 4. I guess I have to upload images to Drop Box and I will show ya.
 
So that 42 feet means that it was 42 feet above "HOME". Not those trees. Yes those trees are like 80 - 100 feet tall. The last part of the video feed shows that the drone was WELL CLEAR of any and all trees.
Share your mission plan from the hub here and we can most likely get a pretty good answer.
 
Dropbox - DJI_ASSISTANT_EXPORT_FILE_2018-07-18_23-44-18.FLY832.log.txt

Dropbox - DJI_ASSISTANT_EXPORT_FILE_2018-07-18_23-44-18.FLY832.recDefs.txtj

For some reason the .dat file is hard to upload to Dropbox. Now If I understand correctly. I need the FC file and the Vision file correct? From the flight we are talking about? I can see the date and time so I know what two they are.. But it was like 466 mb and for some reason I am not able to upload. Errors. We have best internet available so ... ? Any ideas?
 
I need the FC file and the Vision file correct?
The only file we need is the .dat file. Full flights are quite large files.
 
Not according to the log's. This is the last second of the flight. There are no deviations whatsoever. It simply stops. But even the .dat file will not tell you much more in a case such as this. But when you have the device logs for the Entire flight, it is still quite useful.

View attachment 101450

Don't dismiss it, the previous two suspect battery disconnects I analyzed showed a sudden voltage drop from 15V to ~7V in the last 200ms before FC stopped recording. In both cases app logs just stopped as your analysis shows.

So that 42 feet means that it was 42 feet above "HOME". Not those trees. Yes those trees are like 80 - 100 feet tall. The last part of the video feed shows that the drone was WELL CLEAR of any and all trees. So yes I am 99% certain this was the fault of the battery disco. I was flying from on top of a hill. Let me say, that is where the drone mission started. If you look at the path of the mission, the drone had passed WELL clear of all trees on the way down. So on its way back it had already cleared the highest trees before it even got to the waypoint 4. I guess I have to upload images to Drop Box and I will show ya.

Yes altitude from home point with a deviation of +/- a foot or two as it's derrived from the barometer. I can certainly see it climbing back up again on the return leg but it's impossible to rule out anything at this time.
 
You need to configure it sharable......
 
Don't dismiss it
Not dismissing it entirely, however all the data points to the same issue that has been noted on numerous posts and analysis with the P4's, which many of them I have looked as have a few others. I can understand a different issue with your noted voltage drop but these are different. This is apparently why DJI added the latch sensor to the V2's, as they as well seem to understand there was an issue with the battery dislodging. This data shows exactly as others have, and points to the same conclusion. That is all I am saying.
 
Ok humor me here as I am confused. .dat file I get it. Now when I go to DJI Assistant to retrieve the files I can see... File Index, Date, Data File. So I know I need the last flight. In what I see that is File Index 3. Now it is uploading and the file is 150.19MB It consists of an FC file and a Vision file. Both make up the .DAT file for that flight correct?
 

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