Mavic Pro dropped out of the sky

smithlaw · Apr 23, 2017

flyNfrank said:
Sounds like CSC was performed in flight, and the setting in the GO4 app was set to allow CSC in emergency situations(during flight).

Sorry but what is CSC?

mavic6611 · Apr 23, 2017

Combination Stick Command.

mavic6611 · Apr 23, 2017

It's the movement used to emergency cut off the motors during flight. Usually done by moving both sticks inward and down or even outward and down. It's a very common mistake amongst new pilots.

Egika · Apr 23, 2017

But if set to allow CSC in emergency situations it should not shut off the props unless there is an emergency situation. Like drone stuck somewhere or upside down etc...

JLane · Apr 23, 2017

smithlaw said:
I did not retrieve anything from the drone itself. I'm not sure how to do that. I do have the SD card that was in it but I think it is empty.

OK, then I guess we won't be seeing the .dat file for this flight. That's a shame, as it would contain a lot more data than the .txt file from your app. But the .txt would still be useful. You'll find instructions for uploading them at the links I gave you in my previous post.

JLane · Apr 23, 2017

flyNfrank said:
Sounds like CSC was performed in flight, and the setting in the GO4 app was set to allow CSC in emergency situations(during flight).

CSC wouldn't account for the disconnection. This sounds more like another case of a mid-flight power shutdown.

mavic6611 · Apr 23, 2017

Csc can be performed at any time. The aircraft doesn't necessarily need to think there is an issue

JLane · Apr 23, 2017

mavic6611 said:
Csc can be performed at any time. The aircraft doesn't necessarily need to think there is an issue

Depends how you have it set in the app, and I believe the default is that it only works when the Mavic senses a critical error.

MavicGurl · Apr 23, 2017

JLane said:
I actually am very skeptical of any claim that an issue with the cameras would cause this. Even if the Mavic cuts the motors due to thinking it was on the ground, that would not cut the connection to the RC, or power down the Mavic itself. In these recent cases, the Mavic seems to lose all power while in the air.

@stratos , I only vaguely remember your case. Did the Mavic lose all power and disconnect, or just the motors?

Sounds like a gopro karma. Shuts down in midair

theAlexanderGraham · Apr 23, 2017

My Mavic has a build date of 2/8/17, running the most current firmware on all devices.

The only places I'm taking off an landing are big pieces of plain cardboard, floor mat out of the back of my suv, plain asphalt.

I've never experienced any issues with the downward facing cameras becoming confused due to plain background.

flyNfrank · Apr 23, 2017

JLane said:
CSC wouldn't account for the disconnection. This sounds more like another case of a mid-flight power shutdown.

How do you know if a CSC didn't also cause the disconnection? Has the .txt file been uploaded to https://www.phantomhelp.com/LogViewer/Upload/

AlanTheBeast · Apr 23, 2017

smithlaw said:
I got my Mavic Pro last Thursday and flew it 3-4 times with no issues at all. Tuesday morning I decided to go take some shots of a commercial property I am looking to purchase. Just after takeoff I noticed my horizon wasn't level so I decided to land it to do a gimbal recalibration. Right after I pulled back on the stick to lower it, connection was lost and my Mavic dropped hard onto the pavement. The gimbal was broken, the shell was very damaged and the landing gear legs were broken. I sent it back to DJI on Thursday. Has anyone else had this happen? I never really considered this as being a possibility. I've had a P3A for 1.5yrs with no problems that weren't due to my stupidity. This has me a little hesitant whereas before I thought nothing of flying over the ocean, lake, etc.

Thanks all!

Was the battery securely latched?

Did you extract the log from your phone/tablet? Can you upload it here and here

Egika · Apr 23, 2017

flyNfrank said:
How do you know if a CSC didn't also cause the disconnection? Has the .txt file been uploaded to https://www.phantomhelp.com/LogViewer/Upload/

Because CSC (if active) only switches of the motors.
Everyone knows this and you can easily try it yourself (on the ground). No log file needed for this insight.

smithlaw · Apr 23, 2017

flyNfrank said:
How do you know if a CSC didn't also cause the disconnection? Has the .txt file been uploaded to https://www.phantomhelp.com/LogViewer/Upload/

Yes, here is the link:

Phantom Log Viewer - PhantomHelp.com

smithlaw · Apr 23, 2017

AlanTheBeast said:
Was the battery securely latched?

Did you extract the log from your phone/tablet? Can you upload it here and here

Yes I did. Here it is again from the other website.
Airdata UAV - Flight Data Analysis for Drones

Also, It appears I do have the .Dat files. how do I upload or see those?

JLane · Apr 24, 2017

smithlaw said:
Also, It appears I do have the .Dat files. how do I upload or see those?

Upload them to Dropbox or something similar so that some of the data gurus can have a look. And if you're interested in trying to look at the data yourself, check out CsvView or Datcon. CsvView/DatCon

smithlaw · Apr 24, 2017

JLane said:
Upload them to Dropbox or something similar so that some of the data gurus can have a look. And if you're interested in trying to look at the data yourself, check out CsvView or Datcon. CsvView/DatCon

Hopefully this link works for the .DAT files.

Hi D,

Smith Law Group ([email protected]) invited you to view the folder "FlightRecords.DAT Files" on Dropbox.

Go to folder
Enjoy!
The Dropbox team

AlanTheBeast · Apr 24, 2017

I looked at the data and can't come to any conclusion. There is, just before the data stopped, a descent of nearly 2 m/s over 5 seconds. (56 feet to 26 feet). The throttle position was 64% down (I'm assuming the throttle range is 1024..0 for "down" - not sure it can actually go to 0) during that descent. After that the throttle "pops" to neutral position. Immediately after that the data stops.

No evidence of a CSC.

Was the battery secure? There have been at least two plausible cases of a loose battery coming off and causing a crash. But the data above doesn't seem to support that - and in those conditions (vertical movement) it would seem very unlikely.

Need access for my Dropbox account to get at that file so I can analyze it with phantomhelp.com's decoder. Request sent from [email protected].

smithlaw · Apr 24, 2017

AlanTheBeast said:
I looked at the data and can't come to any conclusion. There is, just before the data stopped, a descent of nearly 2 m/s over 5 seconds. (56 feet to 26 feet). The throttle position was 64% down (I'm assuming the throttle range is 1024..0 for "down" - not sure it can actually go to 0) during that descent. After that the throttle "pops" to neutral position. Immediately after that the data stops.

No evidence of a CSC.

Was the battery secure? There have been at least two plausible cases of a loose battery coming off and causing a crash. But the data above doesn't seem to support that - and in those conditions (vertical movement) it would seem very unlikely.

Need access for my Dropbox account to get at that file so I can analyze it with phantomhelp.com's decoder. Request sent from [email protected].

The battery was secure before, during and after. Also, just before control/signal was lost,I was lowering the aircraft so I imagine that's the descent you saw. Thanks. At this point I'm hoping DJI replaces it with one from a different build date, as I've read there have been similar issues with others built around that same time.