DJI Drone Help Forum

Phantom 4 Pro Drops to ground mid flight


#1

While hovering over a high school football field this morning and just rotating the P4P 360 degrees taking video it seemed to lose power or have some kind of major failure as it just dropped straight to the ground from around 260 ft in the air. It sustained serious damage as the camera was knocked clear off, the case cracked, 2 of the 4 propellers were broken although the hub was still attached to the motor. It will still power up and we could download the files off the drone. We received a high wind notification however the winds were only around 15 mph. There was nothing anywhere close for it to run into. Any help would be appreciated. I uploaded the txt file but not sure how to identify it or provide a link.


#2

I recently had my Phantom 3 standard suddenly fall out of the sky (twice) due to a motor issue that suddenly lost power. Did some calibrations and checks after the first crash (was recovered up a tree with minor damage luckily) did a couple of short close to ground test and appeared ok. Flew it again slightly higher and down it came suddenly. Thought it might be an esc issue. On the bench so to speak noticed one motor running slower. I swapped it with the opposing one did a test and the problem was on the other side. It confirmed a motor issue and not an esc problem. Replaced it with a new one and all good (so far) :slight_smile:
Just saying!


#3

That must be a nerve wracking experience! I am new to Drones and am only gaining confidence from day to day, good luck with the replacement, hope you stay in the air!


#4

After uploading your TXT file here, you can copy the link from your web browser and paste it back here. Or just attach the TXT file here.


#5

Thanks for the link. I believe this is what you want.
https://www.phantomhelp.com/LogViewer/706H4TE32BZ73IYUO8NM/

Thanks for any help.


#6

I don’t see anything out of the ordinary, perhaps the battery wasn’t clicked in all the way?


#7

I wondered that myself but I really dont think so because when I put the battery in before flight the 1st time I wasnt sure It was fully in so I pulled it out and reinserted it and felt like it was there. Here is a link to the DAT file.

When I picked up the pieces the battery was out of the unit about .25 inches but the scratches on the battery from the impact are in front of and even go behind the top release button on the battery.


#8

That’s not the right .DAT. FLY064.DAT corresponds to the .txt you submitted.


#9

Ok. I’m a little confused about the numbering but here is the FLY064 file.


#10

I’m confused also. FLY064.DAT should be the .DAT that is associated with DJIFlightRecord_2018-08-04_[08-49-03].txt. Did you use DJI Assistant 2 to retrieve a DJI_ASSISTANT_EXPORT_FILE_2018-XXXXXXX.DAT file and then use ExtractDJI to extract FLY064.DAT? If so, please Dropbox the DJI_ASSISTANT_EXPORT_FILE_2018-XXXXXXX.DAT file


#11

I apologize for the confusion. What you described is exactly what I did. Here is the file you requested. I really appreciate your time in looking at this.

Steve


#12

Thanks. You’ve uncovered a bug in DatCon. No prize, just bragging rights.

Looking at the motor data it can be seen that there is an abrupt voltage drop at the very end of the .DAT

The cause would either be the battery coming loose or a battery failure. There have been many P4P incidents like this.

@sar104


#13

Thanks for your help. Any experience with how DJI reacts to this?


#14

More to the story. I just realized the battery being used was an extra DJI battery we purchased that didnt come with the unit. When we first tried to charg it it did not seem to work right. The green lights didnt seem to work like they were supposed to. I even said we should probably take it back. We tried charging again and everything was fine. I know it was this battery because I put a small red dot on it. I believe we have used this battery at least one other time without incident but it makes me wonder.


#15

Sorry, I’ve not had any experience with DJI on this. There are several ongoing threads over on phantompilots with many different opinions about what DJI should do about these incidents.