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Lucky escape from singal lost

There are probably many reasons why it's a good idea to encrypt the log files, such as to prevent competitors from studying and learning from them

Another good reason would be to guarantee the integrity of the log file, preventing anyone else from editing the contents. The logs are recorded primarily for DJI's own benefit as a factual record of all the various flight parameters. In case of any legal dispute over liability, DJI can point to the actual data to verify the facts of the case.
I can't comment on the first point, much of the data is beyond my understanding so I don't know what could be pirated from them.
But have you ever been able to manipulate the unprocessed data in a txt or DAT and end up with a usable log that can be processed.
Certainly we could probably delete some of the gibberish and we can probably do that even if it is encrypted but would the resulting file be usable ?
I haven't even tried.

I have seen multiple thumbnails in processed logs and at least one has been useful in finding the probably reason for a crash but I have never checked whether or not the thumbnail count matched the photo count that can be obtained from the log.

As for comparison with the images on other social media you are probaly correct but "every little helps" lol.
 
What I don't understand is the dive from 17 meters height to go to almost 0 meters . Is this because I was flying above sea and atti mode kicked in?
Scary incident but I was very lucky to bring it back. I don't know if there was something else I could do?
Lots of people guessing, but so far there's no flight data to look at.
Going into Atti Mode doesn't cause a drone to drop, but your flight data would probably explain that.
The recorded data will show things to help understand the incident and what actually happened.

To post your flight data there are a couple of options ...

1. 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 provides and someone might be able to analyse it and give you an understanding of the cause of the incident.
or
2. Just post the .txt file here
or
3. If you use Airdata, you can view the flight data on Airdata and post a link for the Airdata report

If you are using one of the controllers with an integrated screen, the txt files are to be found here:
Android\data\dji.go.v5\files\FlightRecord
 
I still wonder whether that bizarre flyaway should be attributed to the solar flare or like your Mavic 3, was the result of GPS jamming
What you described doesn't sound like a result of solar activity or GPS jamming.
But unless you post your flight data, you'll have to continue to wonder and won't know what happened or how to prevent it happening in future.

See post #22 for details.
 
Loosing GPS signal may also be caused by a bad compass calibration.
You cannot fly properly with a bad compass calibration and would know about it as soon as you launched.
In former times with Phantoms there was a possibility to do an emergency calibration while in air, by several 360° turns around the yaw axis.
I've never heard of this.
It seems highly unlikely.
Would be worth trying same with actual models in case of GPS loss.
Where a compass issue (a yaw error) puts the drone into Atti Mode, GPS reception is not lost.
The satellite data continues to be recorded, but is not used.
In those incidents the compass isn't the problem and recalibrating it (if that was even possible in flight) wouldn't fix anything.
But no-one is going to be able to control their drone in that situation anyway.
 
You cannot fly properly with a bad compass calibration and would know about it as soon as you launched.
For sure you can. Detecting a bad calibration on ground is almost impossible for the flight controller.
Where a compass issue (a yaw error) puts the drone into Atti Mode, GPS reception is not lost.
The satellite data continues to be recorded, but is not used.
That's true, but the firmware handles it same as GPS loss. There is no dedicated error message for the compass problem during flight.

If I ever will run into that situation I will at least try the emergency calibration instead of just awaiting loss of the drone or crash and if I can get back GPS mode this way this method would be proofed.
 
For sure you can. Detecting a bad calibration on ground is almost impossible for the flight controller.
It sounds like your understanding of what compass calibration is/does is questionable.

But people aren't getting "bad compass calibrations".
Your compass calibration doesn't just go bad.
 
It sounds like your understanding of what compass calibration is/does is questionable.

But people aren't getting "bad compass calibrations".
Your compass calibration doesn't just go bad.
It sounds like your understanding of electronic compasses is questionable. Simply pack your drone within the range of a strong magnetic field (e.g. loudspeaker or power cable within a (electric) car and your calibration will be history.
 
It sounds like your understanding of electronic compasses is questionable. Simply pack your drone within the range of a strong magnetic field (e.g. loudspeaker or power cable within a (electric) car and your calibration will be history.
Before you insist on digging yourself any deeper into that hole, please take a look at this excellent post by @sar104, someone who actually knows what he's talking about.

A short explanation of compass function, calibration and errors.
 
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Hmm you got me thinking Gerd, and that is not always a good thing. This is my other car, a 1976 Caterpillar D7G LGP bulldozer with low-ground-pressure wide tracks that enable it to excavate catfish ponds in deep slushy mud. Now this beast weighs north of 20 tonnes and is parked about 20 feet from where I place a plastic picnic table to launch my drones on Litchi waypoint missions.

In 5 years of launching Phantoms and Mavics near this mountain of iron, I have never encountered any magnetic interference issues, and have never seen a drone depart at full speed uncommanded as my late and lamented MPP did a couple of weeks ago. All the same, as I ruminate over the loss of my Mavic Pro Platinum, I cannot help but wonder whether my prized dozer might be the cause of that drone's compass anomaly and final flight into oblivion.

I am still trying to locate the flight data of that final flight as recommended by Meta4, but so far have not made any headway. Oddly enough the drone did not record any video footage as it careened off toward the horizon that fateful day, so I have no visual record either, of what happened after that unexpected departure from controlled flight
 
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Retrieval of flight data is a mystical science that still baffles me so I am muddling along in a bid to educate myself in this aspect of drone flying that I overlooked in the past.
I assume the drone's controller used a phone, if correct and if the phone is an android phone and your computer is a windows machine, connect the phone to the computer via a USB cable that can transfer data. Some USB cables are charge only cables.
Assuming you use a data cable the phone should show up on the computer, if it does not than check this phone for messages that mention allowing data transfer, allow data transfer.
The phone should then show up on the computer. if it does open the following chain of folders
Computer/phone's-name/Phone/DJI/dji.go.v4/FlightRecord
That's from memory so I might have made a mistake in the order of the phone's name and Phone.
In FlightRecord you should see files whose name starts DJIFlightRecord . Upload the last one to phantom help.
It took far longer to type this message than it should to access the folder on the an android phone using a windows computer.

If you are using apple device/s then things are a bit more fiddly.
 
Retrieval of flight data is a mystical science that still baffles me so I am muddling along in a bid to educate myself in this aspect of drone flying that I overlooked in the past.
It's not that hard.
I laid it out for you in post #22.
 
I suspect not a great deal.
BUT, in truth and donning an aluminium foil hat, do we know all that the logs record ? We certainly can not see all the data they record?
Why start encrypting the phone and drone DATs ? P3 drone DATs are readable and I have made use of them. Post P3? they started to encrypt the DATs on the drone and finally the screen device DATs. I thought they had seen the light when the Mini 3 Pro had readable screen devices DATs but they have gone back to encrypting them.
The app can recognise the flights flown under the current login, it displays ONLY those logs.
It does not display logs flown under other logins, and nothing in any of the CSVs I have looked at gives any indication of which login was used.
The .txt flight log includes low resolution copies of the photos that we shoot. Airdata and FlightReader can, from memory, show them.
From what I have read, this process was stepped out as a response to the initial claim that DJI was collecting data on personal usage instead of just about how the electronic hamsters run around in the gubbins of the drone, an attempt to reassure concerns regarding data integrity.

I wish all the rest of the web based companies and 'social' media platforms would take a leaf out of the DJI playbook and be accountable for their blatant and totally invasive snooping as well.
 
It is safe to assume that DJI is capable of gathering geo-location data on every drone they have ever manufactured, which is a bit unsettling since I treasure my anonymity.
So, Joe Bloggs has the WiFi on their phone or controller switched off, how are DJI going to get the data ? Explain that to me please.

As far as I know the only data they received is through either synced logs which is supposedly a voluntary process though I have accidentally triggered it on at least one occasion ..... or through info relayed whilst logging into the app.
In the latter case I would guess that virtually ever company does the same thing
 
It is safe to assume that DJI is capable of gathering geo-location data on every drone ...
No, it's not safe to assume that.

Geo-location data is used by the drone for its own navigation abilities. To preserve your precious anonymity, you could completely block/disable/uninstall the GPS antenna inside your drone . The drone would still fly, but you'd sacrifice considerable functionality.

The reasons for actively recording, and subsequently being able to examine geo-location data saved in flight logs have been discussed in many prior posts.

DJI only "gathers" this data if you choose to share it with them by syncing your flight logs to their servers. There is an option in the app to have the flight logs automatically synced, switched off by default, and it is your choice to set it either way.

If you're still worried (based on your "safe" assumption, without evidence) that it's somehow a threat to your anonymity, DJI actually has no way to surreptitiously retrieve those flight logs if you deny them an internet connection to your drone or controller. Don't connect it to WiFi, or just delete the logs yourself before connecting.

As of this week, it's no longer even possible to sync logs via their apps in the USA, because DJI have entirely disabled that ability. Thanks to your gov't, that useful optional functionality is no longer available to US operators of DJI drones.

Your anonymity is now safe, replaced instead by that other clever service your gov't has introduced to better protect your geo-location anonymity -- no longer optional, but actually legally required Broadcast Remote ID and, soon enough, Networked Remote ID. Brilliant, eh?

Now, you can rest assured the some bored Chinese technician can no longer determine how many times you've flown your drone around your own yard, if you've ever bothered to sync your flight logs. Instead you now can have all your nosy neighbours instantly alerted by their Remote ID Karen Apps, ready to track you and drone every time you fire it up. That's so much better, right? 🚁
 
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It is safe to assume that DJI is capable of gathering geo-location data on every drone they have ever manufactured,
DJI have no way to tell anything about your flying (unless you've chosen to upload your flight data to their server).
Not only that, DJI couldn't care where/when/why/how you flew.
which is a bit unsettling since I treasure my anonymity.
We know ... you're never going to post the data from your recent incident, are you?
 
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