DJI software bug surrounding authorised boundaries caused me to lose my drone to the sea

[J4MEJ]

For all the above reasons I installed Drone-Hacks on my M2P removing DJI Geo Fencing. I still follow FAA rules and use LAANC where needed. But I never have to deal with DJI to tell me when and where I can fly. DJI Geo fencing had caused many flight risks, some resulting in near losses, others losing their drones.

Don't suppose you could link me to a comprehensive guide on how to do this? Thanks

J

 

[slup]

Don't suppose you could link me to a comprehensive guide on how to do this?

Drone-Hacks, the best way to hack your DJI Drone

 

[Zbip57]

It is a legitimate complaint though.

Lets say there's a red restricted zone within which DJI prevents you from flying. You define a hexagonal shaped area within that red zone and manage to obtain the required authorizations to take off and fly only within that green hexagon authorization zone. In this example it makes perfect sense that you'd be prevented from straying beyond the boundaries of the hexagonal green authorized area to prevent you from trespassing into any of the remaining red restricted zone.



But what if your defined hexagon shape overlaps the boundary edge of the red circle, as shown below. Surely DJI's geofence system should be able to distinguish between the edges of the hexagon that border on red restricted zones versus the other edges which empty out into similarly unrestricted green areas.

In this case it's not logical to prohibit leaving the custom defined authorized zone, as long as you are moving from one green area to another regardless of which direction.



In @J4MEJ 's case, he flew from an orange "Warning Zone" into his custom defined authorized zone, but was then unable to fly back out into the same orange "Warning Zone".

There's nothing preventing one from flying in a Warning Zone. It merely pops up a warning message to let you know there's something you need to be aware of. It requires no acknowledgement from the pilot, and otherwise does not prevent you from flying there.

He's allowed to fly within the orange Warning Zone, and allowed to fly within his defined authorized zone. So why shouldn't he be allowed to fly from one to the other in either direction?

 

[HoozierDroneDaddy]

Don't suppose you could link me to a comprehensive guide on how to do this? Thanks

J

www.drone-hacks.com
Here is the page showing the acceptable drones.

Drone-Hacks, the best way to hack your DJI Drone - Hacks

Drone-Hacks is the most easy and best way to hack your DJI Drone. Depending on your drone you can hack the NFZ, Altitude limit, FCC signal power and much more.

drone-hacks.com

I purchased the NFZ hack. Make sure your on the latest FW that works to your satisfaction. If you update to a newer FW after installing the hack, you will have to do the hack again. I installed it on my M2P with the FW I had been using for over a year with no issues.
Look through their site and read their notes and info on the hacks. I have been very happy with it especially not dealing with the DJI fencing issues.

 

[HoozierDroneDaddy]

It is a legitimate complaint though.

Lets say there's a red restricted zone within which DJI prevents you from flying. You define a hexagonal shaped area within that red zone and manage to obtain the required authorizations to take off and fly only within that green hexagon authorization zone. In this example it makes perfect sense that you'd be prevented from straying beyond the boundaries of the hexagonal green authorized area to prevent you from trespassing into any of the remaining red restricted zone.

View attachment 150097

But what if your defined hexagon shape overlaps the boundary edge of the red circle, as shown below. Surely DJI's geofence system should be able to distinguish between the edges of the hexagon that border on red restricted zones versus the other edges which empty out into similarly unrestricted green areas.

In this case it's not logical to prohibit leaving the custom defined authorized zone, as long as you are moving from one green area to another regardless of which direction.

View attachment 150098

In @J4MEJ 's case, he flew from an orange "Warning Zone" into his custom defined authorized zone, but was then unable to fly back out into the same orange "Warning Zone".

There's nothing preventing one from flying in a Warning Zone. It merely pops up a warning message to let you know there's something you need to be aware of. It requires no acknowledgement from the pilot, and otherwise does not prevent you from flying there.

He's allowed to fly within the orange Warning Zone, and allowed to fly within his defined authorized zone. So why shouldn't he be allowed to fly from one to the other in either direction?

I remember a couple of years ago, if you flew across the barrier into a restricted zone, the DJI geo fencing would force land your drone with no option to return or fly out of that zone. Bad Ju Ju

 

[Zbip57]

I remember a couple of years ago, if you flew across the barrier into a restricted zone, the DJI geo fencing would force land your drone with no option to return or fly out of that zone. Bad Ju Ju

It should stop at the border and prevent you from ever crossing into the restricted zone, and it should prevent you from ever taking off within a restricted zone.

But, if you take off inside or fly across the border into a restricted zone before the drone has achieved a good GPS lock, then the drone has no way of knowing where it's at. The moment it does achieve GPS lock and wakes up to find itself within a restricted zone, then it will immediately force land.

 

[RangerEd]

Ah, I see what you mean now. It's confusing because your images show different Home Positions from different flights, so it was difficult to see what's going on. I overlaid your images to make them a little easier to understand.

The big yellow Home Point in the centre of your purple boundary unlocked authorization zone is from a previous flight. The flight route at the bottom of the image, with the various coloured tags, is where you encountered your problem.

View attachment 150045

The red boundary shows your unlocked authorization zone, which was still active at the time of this flight. Your flight started on the island outside of this boundary and your drone eventually crossed over the red line into the authorized unlocked zone, but then was prevented from crossing back outside to leave the zone. That left the drone stranded within the zone and unable to return to you.

View attachment 150046

I've never had the need to use any unlock features, so I have no personal experience at how they work. But I would think if you define a custom boundary within which you receive authorization to operate, that would create a custom perimeter within which you have permission to fly freely only if you remain within that perimeter.

You took off from a location where flight is already permitted, but crossed into the perimeter that you created, and then were prevented from leaving the boundaries which you earlier created for yourself.

I'm not sure you could call this a software bug, as it appears to have worked exactly as designed.

Wow ... that was a good job analyzing what he did. It's to bad the OP didn't explain lucidly what happened but you did.
You're right though ... is this what's intended for the custom geo-zone? And why would you create a geo-fence and not launch from within that zone. I'm thinking if you create a geo-fence that you're basically telling your drone not to go outside the geo-fence. And it's probably the same reason he was able to recreate the "problem".

 

[J4MEJ]

I know when I used custom unlocks a couple years back (I had 9 of them set up for different areas in my region), you went into the controller and turned on the needed unlocked zone when you wanted to fly there. But you could also turn it off. If he had gone into the controller and turned his unlocked zone off, would that have let him cross back over the barrier, or would it have forced landed the drone similar to when you fly into one that your not authorized in?

Hi, I'm replying specially to your comment because you query about what would happen if I tried to go into the settings to disable the zone whilst in flight.

Today I re-enacted this scenario in a controlled environment with a friends drone.

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You'll note that the authorisation zone cannot be disabled during flight.

 

[DearAman]

I'm going to save myself time and link to the reddit thread.

I'm hoping some of you can help me out by reading the log and telling me if I have an argument here for a replacement.

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For ease, the log can be found here:

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

I also attach the file

Very sorry for the loss of your beloved drone and my sympathies remain with you. I too have had similar but fortunate escapes from disaster because my house is ON THE LINE of the geo fencing perimeter line which splits my roof in two, virtually. I live smack in the center of two airports, too! Ok so I'll let that sink in. The last time I almost lost my Mavic 3 was when it had 7% battery left and the drone refused to come within 4 feet of my rooftop, just out of reach for me to hand catch it without taking a dive to the earth's core. so I just sent it with a prayer about 300 feet away to another apartment building and to its roof and landed there, and the screen on my controller lost transmission just before it landed there. I had to run to get it. I know you're going through the pain of losing it, but I wanted to say that please to keep an alternate landing spot figured out in your future drone flying days, which are sure to come and make this incident a thing of the past. The Mini 2 is too light to send it out to sea with the windy conditions there and the RTH may not be able to cope always with strong winds and possibly rain at that location. Good Luck bro... Hope you get a nice drone again, soon.

 

[Yorkshire_Pud]

The last time I almost lost my Mavic 3 was when it had 7% battery left a

Whilst I understand unintended things happen I wouldn't make a habit of having the drone in the air at such low percentages.

If the Mavic 3 behaves in the same way as other DJI drones it will, at some point around there, enter critical battery levels and start to land. You can not cancel such a landing but you can keep the drone in the air if you give it significant amounts of throttle, however the speed with which the drone can move horizontally may be significantly reduced and the drone probably does not respond 'crisply' to commands to move horizontally i.e. control of the drone becomes woolly.
Yes I have done it but only when the drone was safe and yes people have done it and even flown to zero percent and 'below' when caught over water etc.. but it's a last resort.

 

[R3SKT]

Having read all of the previous postings on this thread I am both in admiration and awe for the understanding and technical dissection of what happened to J4MEJ's drone. The amount of time expended to better understand what occurred during that flight is boggling to me. One thing is for sure, I will not forget about this incident, and will be very wary of zones moving forward.

Question - ? If you lose your drone, how do you then pick up your flight log details for that last flight?

 

[J4MEJ]

Having read all of the previous postings on this thread I am both in admiration and awe for the understanding and technical dissection of what happened to J4MEJ's drone. The amount of time expended to better understand what occurred during that flight is boggling to me. One thing is for sure, I will not forget about this incident, and will be very wary of zones moving forward.

Question - ? If you lose your drone, how do you then pick up your flight log details for that last flight?

The flight log details are stored on the remote, which in this case was my phone.

P.S. Nice to see someone local. I'm 10min from Marlow.

 

[R3SKT]

The flight log details are stored on the remote, which in this case was my phone.

P.S. Nice to see someone local. I'm 10min from Marlow.

Ahh, so in my case then, the flight log should be on the RC .... just need to understand how to locate it next then

Edit:~ Found it! Under Profile ..... I get there eventually!

 

[HoozierDroneDaddy]

Wow ... that was a good job analyzing what he did. It's to bad the OP didn't explain lucidly what happened but you did.
You're right though ... is this what's intended for the custom geo-zone? And why would you create a geo-fence and not launch from within that zone. I'm thinking if you create a geo-fence that you're basically telling your drone not to go outside the geo-fence. And it's probably the same reason he was able to recreate the "problem".

You are already in a Geofenced area, live there or otherwise. Then you get the DJI unlock to fly. And if you want to fly across to an area that is not DJO geofenced, it will not let you. You have to turn off the custom unlock. Then you cannot return. As said above, once you get the custom unlock, you should be able to go both ways as long as the you have authorization for both areas. Unfortunately, DJI does not let you.

 

[Zbip57]

Ahh, so in my case then, the flight log should be on the RC .... just need to understand how to locate it next then

Edit:~ Found it! Under Profile ..... I get there eventually!

For a really excellent description on how to retrieve the flight data, see this thread by @sar104 :
mavicpilots.com/threads/mavic-flight-log-retrieval-and-analysis-guide.78627/

 

[R3SKT]

For a really excellent description on how to retrieve the flight data, see this thread by @sar104 :
mavicpilots.com/threads/mavic-flight-log-retrieval-and-analysis-guide.78627/

Oh my days, having just read through all of that document, I find myself needing A: another large glass of red wine and B: a sharp tap on the side of my head to wake up to the fact that there are some seriously clever people walking amongst us.