Phantom 4 Pro + Dropped from the sky

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A friend sent the drone out over to pond tonight and about 30 sends into the flight the drone dropped to the ice. I'm guessing the battery wasn't seated correctly. Can anyone confirm what happen from these flight logs? Guessing these are the files!

Thanks,

Dale
 
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There are 3 files from today from the drone Fly***.Dat file I assume these are the files of interest?

We were able to recover the drone.
 

Meta4

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There are 3 files from today from the drone Fly***.Dat file I assume these are the files of interest?
Go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record from your phone or tablet.
That will give you a detailed report on the flight data.
Come back and post a link to the report it gives you.
 
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Hi Mete4 I have the integrated screen with the controller. Kinda computer savvy but need a but more help....;-)
 

sar104

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Hi Mete4 I have the integrated screen with the controller. Kinda computer savvy but need a but more help....;-)
If this was a battery issue then the mobile device txt logs and DAT files are no use. You need to post the aircraft DAT files as you were attempting to do previously.
 
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It kinda hit the ice hard and a few parts are not attached including the camera guessing it a total lost but want to know what happed.
 
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Was able to get those files from the aircraft with easy. my email is [email protected] I'll send you the files directly if you have means to look at them. Send me an email and I'll send them to you. But why can't I upload them?
 

sar104

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Was able to get those files from the aircraft with easy. my email is [email protected] I'll send you the files directly if you have means to look at them. Send me an email and I'll send them to you. But why can't I upload them?
Two reasons: the file extension is .DAT (not allowed) and the file size is too large (> 10 MB). Use Dropbox.
 
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Here is the link to the aircraft file. At least I think this it the crash file.

massapoag.org/DJI_Log/FLY199.DAT

Thanks!

Dale
 

sar104

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Here is the link to the aircraft file. At least I think this it the crash file.

massapoag.org/DJI_Log/FLY199.DAT

Thanks!

Dale
That may be the correct file, but it is not converting properly in DatCon - I only get the first 25 seconds of the flight, even though DatCon thinks it lasts 321 s.

Any ideas @BudWalker?
 
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That may be the correct file, but it is not converting properly in DatCon - I only get the first 25 seconds of the flight, even though DatCon thinks it lasts 321 s.

Any ideas @BudWalker?
The .DAT wasn't closed properly. Almost certainly because the battery was abruptly disconnected.
 
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Gotta make sure that battery is clicked in good with an extra top and bottom push to seat it. Poor designing that has ruined the day for many owners who are unfamiliar with the problem. Glad you were able to recover it.
 

sar104

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The .DAT wasn't closed properly. Almost certainly because the battery was abruptly disconnected.
Interesting - I haven't seen that before, and we've seen lots of flights where the battery disconnects and the DAT file motor voltage record records the initial voltage drop on disconnect. Is an improperly-closed DAT file recoverable?
 

PhantomWetSuits

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A friend sent the drone out over to pond tonight and about 30 sends into the flight the drone dropped to the ice. I'm guessing the battery wasn't seated correctly. Can anyone confirm what happen from these flight logs? Guessing these are the files!

Thanks,

Dale
If you only knew how common this was : This is very likely what happened.
Phantomrain.org
Gear to fly in and out of the storm.

 
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Interesting - I haven't seen that before, and we've seen lots of flights where the battery disconnects and the DAT file motor voltage record records the initial voltage drop on disconnect. Is an improperly-closed DAT file recoverable?
Say what?? You and I looked at several of these.
Mystery Crash P4 flewn with Litschi
Maybe you're trying to forget:)

The .DAT file is written in blocks - just like in a normal file system. Records are written into a block until the block is full. At that point the block is "closed" and future records start being written into a new block. When a .DAT file is deleted it's blocks are then made available to be used in a new .DAT file. When the last record of the log is written to the .DAT file the location of the last byte is recorded within the block. If that didn't happen then it looks like there are extra records - past the last record that was actually written. The bytes for those extra bogus records are whatever was in that block from the last time the block was used in a file.

You can "recover" by ignoring those last data points. Or, you can modify the .csv and remove those final rows. I ran DatCon at the highest sampling rate and then deleted these rows.
1553091226840.png
 

sar104

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Say what?? You and I looked at several of these.
Mystery Crash P4 flewn with Litschi
Maybe you're trying to forget:)

The .DAT file is written in blocks - just like in a normal file system. Records are written into a block until the block is full. At that point the block is "closed" and future records start being written into a new block. When a .DAT file is deleted it's blocks are then made available to be used in a new .DAT file. When the last record of the log is written to the .DAT file the location of the last byte is recorded within the block. If that didn't happen then it looks like there are extra records - past the last record that was actually written. The bytes for those extra bogus records are whatever was in that block from the last time the block was used in a file.

You can "recover" by ignoring those last data points. Or, you can modify the .csv and remove those final rows. I ran DatCon at the highest sampling rate and then deleted these rows.
View attachment 109780
Right - I remember getting spurious additional data, but in this case it appeared to be missing data - I never saw those additional rows. Maybe that was due to the sample rate I chose, which was 200 Hz. In any case, I guess that means that the flight was that short, so no problem. Thanks for the reminder.
 
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A friend sent the drone out over to pond tonight and about 30 sends into the flight the drone dropped to the ice. I'm guessing the battery wasn't seated correctly. Can anyone confirm what happen from these flight logs? Guessing these are the files!

Thanks,

Dale
While it is rare, they do malfunction from time to time.
I’ve been flying DJI products since the Phantom 2. I own three P3 Pros, and three Phantom 4 pros and this is the first time that any of my Phantoms have dropped out of the sky.
I calibrated the P4, took off straight up, ascended to about 200 feet, looked around for about 10 seconds when all-of-a-sudden the P4 starts to drop.
I tried to regain control, but the Phantom would not respond. As it descended, the props made the most terrifying noise I have ever heard coming from any Phantom I have ever owned.
As the quadcopter made its very quick descent, I noticed that is was headed right for me.
I scrambled to get out of the way, as it just missed me, and landed upside down on the asphalt. Considering the altitude from which it descended, the only discernible damage was to the top of the props which continued to turn as it lay upside down on the asphalt. I had a difficult time stopping the motors. They continued to spin rapidly on the asphalt and scoured the top of the propellers.
When I picked up the craft, I noticed that one of the motors felt much-much hotter than the others. I assume that one of the motors malfunctioned.
This Phantom was very new and this was only its 4th flight. Two of the other flights were over a lake.
Although I hated to see it crash, it could have been far worse.
 
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If you only knew how common this was : This is very likely what happened.
Phantomrain.org
Gear to fly in and out of the storm.

This advertisement post has zero to do with the topic of this thread. :rolleyes:
 
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