Where is the flight data stored? (a) P4P (b) micro SD (c) RC or (e) Tablet?

[MMerino]

Hi, I am a bit confused as to where the flight data is stored (and what kind of information is contained in each type of file).

1- If I connect my P4A to DJI Assistant 2 (on my laptop) I can download .DAT files (stored inside the P4A or in the micro SD card?). What type of information do these files contain? How can I analyse it's contents?

2- If I connect my iPad mini 4 to iTunes, I can download .TXT files (stored in the iPad only or also in the P4A or RC?). I have used these with AIR DATA UAV.

3- I have heard some people have connected their RC (through the micro USB port) to a computer and have downloaded some files (which?) using a "special" DJI software...

4- Any other ways of obtaining flight data form a P4A?

I appreciate your help. TIA!

 

[msinger]

1- If I connect my P4A to DJI Assistant 2 (on my laptop) I can download .DAT files (stored inside the P4A or in the micro SD card?). What type of information do these files contain? How can I analyse it's contents?

DAT files contain the most available flight data. Those files are stored on the Phantom's internal memory. DatCon is the best available tool to read them. See more details here.

2- If I connect my iPad mini 4 to iTunes, I can download .TXT files (stored in the iPad only or also in the P4A or RC?).

TXT flight logs are only stored on your mobile device. AirData doesn't show much data from those logs. Try my log viewer or the TXT-to-CSV Log Converter.

4- Any other ways of obtaining flight data form a P4A?

No.

 

[Meta4]

Hi, I am a bit confused as to where the flight data is stored (and what kind of information is contained in each type of file).

Flight data is stored in two places.
Very detailed data for the last few flights is stored on an SD card inside your Phantom.
That's the .dat file that you can get with Assistant 2.
You also have a .txt file stored in the app that has good information for each flight.
The easiest way to view the .txt file data is to ....
Go to DJI Flight Log Viewer
Follow the instructions there to upload your flight record from your phone or tablet.
The removable SD card only contains your images and videos.

 

[DOC 1500]

What useful information comes from the flight data ?
I'm new at this.

 

[msinger]

What useful information comes from the flight data ?

Check out this list.

 

[sar104]

TXT flight logs are only stored on your mobile device. AirData doesn't show much data from those logs. Try my log viewer or the TXT-to-CSV Log Converter.

I don't entirely agree with that assessment. Both the PhantomHelp log interpreter and AirData produce similar kml and csv output:–

PhantomHelp:
Id, Time(seconds), Time(text), Latitude, Longitude, FlightMode, Altitude(feet), Altitude(meters), VpsAltitude(feet), VpsAltitude(meters), Speed(mph), Speed(m/s), HomeDistance(feet), HomeDistance(meters), HomeLatitude, HomeLongitude, GpsCount, BatteryPower(%), BatteryVoltage, BatteryVoltageDeviation, BatteryCell1Voltage, BatteryCell2Voltage, BatteryCell3Voltage, BatteryCell4Voltage, VelocityX, VelocityY, VelocityZ, Pitch, Roll, Yaw, RcAileron, RcElevator, RcGyro, RcRudder, RcThrottle, NonGpsError, GoHomeStatus, AppTip, AppWarning, AppMessage​

AirData:
latitude, longitude, altitude(feet), ascent(feet), speed(mph), distance(feet), time(millisecond), datetime(utc), satellites, voltage(v), max_altitude(feet), max_ascent(feet), max_speed(mph), max_distance(feet), compass_heading(degrees), pitch(degrees), roll(degrees), isPhoto, isVideo, rc_elevator, rc_aileron, rc_throttle, rc_rudder, gimbal_heading(degrees), gimbal_pitch(degrees), battery_percent, voltageCell1, voltageCell2, voltageCell3, voltageCell4, voltageCell5, voltageCell6, battery_temperature(f), flycStateRaw, flycState, message​

The basic fields needed for flight forensics are the same, with a few differences in the other data converted. Overall I tend to prefer the PhantomHelp conversion, but both work fine in most situations.

PhantomHelp does present some of those data on the web page, but not enough to be very useful, specifically because stick inputs, pitch, roll and yaw, latitude and longitude are missing. AirData has no equivalent data presentation, but does provide a more compact and useful notifications list. AirData also has some more advanced analysis tools to estimate wind field during flight, sensor performance, signal map, power characteristics etc., although some of those require a subscription.

Neither site provides any useful graphical analysis tools which are essential to any real analysis of flight telemetry - for that you need to use @BudWalker's excellent CsvView, or some other data analysis software of your choice, preferably including data differentiation, integration, curve fitting, statistics and smoothing.

As a result, I generally use PhantomHelp for conversion to CSV, AirData for data summaries and derived values, and then a dedicated data analysis program to process the telemetery data. Unless the DAT file is available, of course, which dwarfs the information available in the device logs.

 

[MMerino]

Thanks everybody for the useful information.

Just one more point: If I fly several drones and with several tablets/phones, is there a way to have all flight info in one place? (e.g. if I fly a friend's drone with my iPad or if I fly my P4A with someone's tablet, in both cases I will be missing some info...). In my case, I had my P4A replaced by DJI with a new one after 3 weeks of purchase, so all DAT files in the drone are lost...(I thougt they were saved in my tablet). Another day I had to fly my P4A with someone's iPad (I forgot mine) so the txt files remained in another tablet...What a mess!

 

[msinger]

If I fly several drones and with several tablets/phones, is there a way to have all flight info in one place?

If you sync your flights in DJI GO (while logged into your DJI account), you'll be able to store all of the TXT flight logs from the current mobile device in DJI's system. When switching devices, you can sync again to download those uploaded TXT flight logs.

For the DAT flight logs, you'll need to manually download them from each aircraft and store them offline/online somewhere. DJI GO is not able to sync them.