P3P crashed... Here is my flight log

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Well, it happened. After over 500 miles my P3P fell from the sky.

I was hovering about 50' above the ground when the P3 started to make a loud and disturbing noise. Within a second or two it pitched hard to the side and came crashing down. (About 1 min 17 sec into flight)

All 4 props were still on when it crashed. Battery started at 100%. No errors came up Litchi. I have uploaded my flight log if any of the experts wish to to take a look and let me know what happened. I'm assuming motor failure, but I would like to know how to interpret the data.

Phantom Log Viewer - PhantomHelp.com


Sent from my SM-T810 using PhantomPilots mobile app
 
Well, it happened. After over 500 miles my P3P fell from the sky.
I was hovering about 50' above the ground when the P3 started to make a loud and disturbing noise. Within a second or two it pitched hard to the side and came crashing down. (About 1 min 17 sec into flight)
It's good to see a flight log we can read for a change.
I can't see anything in the flight data to explain the incident.
It had power all the way into the ground and there is no indication of CSC.
Looks like a case to hand on to DJI support.
 
Well, it happened. After over 500 miles my P3P fell from the sky.

I was hovering about 50' above the ground when the P3 started to make a loud and disturbing noise. Within a second or two it pitched hard to the side and came crashing down. (About 1 min 17 sec into flight)

All 4 props were still on when it crashed. Battery started at 100%. No errors came up Litchi. I have uploaded my flight log if any of the experts wish to to take a look and let me know what happened. I'm assuming motor failure, but I would like to know how to interpret the data.

Phantom Log Viewer - PhantomHelp.com


Sent from my SM-T810 using PhantomPilots mobile app

Upload that same .txt file here if you could.
 
The loud noise you heard probably came from the left back motor
upload_2016-9-7_7-50-9.png

At about 82 secs the load started increasing as did the commanded speed. Kind of like the motor started to fail or got obstructed and the ESC commanded it higher to compensate. At 84 secs load went to 0 and the speed dropped to almost 0 indicating a total failure of that motor or its ESC.

However, there is an inconsistency. The left back motor speed increases before the failure at 84 secs.
upload_2016-9-7_7-57-33.png

I would have expected the speed to decrease since there were indications that the P3 was having difficulty maintaining speed. The opposing (right front) motor decreased speed which would be expected if the left back decreased speed. When there is a propulsion issue with a motor the opposing motor will decrease speed to compensate and keep the A/C from tumbling. IMHO its OK to treat this inconsistency as possibly due to the way motor speed data is obtained.
 
@MedinaTaylor I should have asked you if you've attempted a motorStart since the incident. If not, you could try that - just a motorStart, don't try to fly it. I'd be interested to know if the result is an ESC error followed by a motor shutdown. The DJI Go App will report the ESC error. I don't know about the Litchi app.
 
@MedinaTaylor I should have asked you if you've attempted a motorStart since the incident. If not, you could try that - just a motorStart, don't try to fly it. I'd be interested to know if the result is an ESC error followed by a motor shutdown. The DJI Go App will report the ESC error. I don't know about the Litchi app.

I did not.

Unfortunately I have already shipped it to DJI so I can not do it.
 
Thanks everyone for checking out my flight log.

DJI had repaired my bird under warranty and it's already on its way back to me.

Sent from my SM-T810 using PhantomPilots mobile app
That's great news. If DJI provides any info about the cause or what they repaired/replaced would you please share that.
 
I'm glad DJI was able to help. I just download Litchi and did not want to use App after your post.

I still plan on using Litchi. I am confident it was a hardware issue, and had nothing to do with the app.

Did you tell them you were using Litchi?

Nope. They never asked. I would guess they could tell from the flight logs, but who knows.
 
That's great news. If DJI provides any info about the cause or what they repaired/replaced would you please share that.

Here is a copy of the email from DJI


Dear DJI User,


After testing and diagnosing your product, DJI will provide you with the free repair service. The repair is expected to be finished in 2 to 3 working days, then the product will be sent back to you. Thank you for choosing DJI.


Item Quantity Unit Price(USD) Total Price(USD)
Phantom 3 top cover 1 3.00 3.00
Phantom 3 bottom cover component 1 8.00 8.00
2312A electric motor (cw) 2 18.00 36.00
Service Charge 1 70.00/H 70.00
Freight: 0.00
Total Amount: 117.00
Discount: -117.00
DJI Care deduction: 0.00
Total Payment: 0.00
 
I saw a post over on DJI Forum by a DJI employee about the warranty when a 3rd party app is used. The gist of it was that the warranty couldn't be honored because the Litchi log doesn't contain the flight data required to determine the cause of an incident. Presumably, if the .DAT is available then using a 3rd party app would not affect any warranty claim. Compared to the .txt produced by the Go App the .csv produced by Litchi is woefully lacking data useful for incident analysis.
 
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The loud noise you heard probably came from the left back motor
View attachment 64239
At about 82 secs the load started increasing as did the commanded speed. Kind of like the motor started to fail or got obstructed and the ESC commanded it higher to compensate. At 84 secs load went to 0 and the speed dropped to almost 0 indicating a total failure of that motor or its ESC.

However, there is an inconsistency. The left back motor speed increases before the failure at 84 secs.
View attachment 64240
I would have expected the speed to decrease since there were indications that the P3 was having difficulty maintaining speed. The opposing (right front) motor decreased speed which would be expected if the left back decreased speed. When there is a propulsion issue with a motor the opposing motor will decrease speed to compensate and keep the A/C from tumbling. IMHO its OK to treat this inconsistency as possibly due to the way motor speed data is obtained.


Bud,
How did you extract the motor stats (command, speed & load) from the file with CsvView. Is it because it is a litchi file and not a DJI GO app file? The DJI GO app TxT file loads OK but the DJI GO app DAT file will not load.
 
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