AutoLanding in Authorization Zone after lost signal between Mini and controller.

This happened to me this AM while flying in an authorized area over the San Diego River.

My flight on Jan 29 at 7:31AM PDT is the flight in question. The starting location is in an Authorization Zone. I authorized the flight by downloading the authorization from my FLY app to the Mini. As can be seen from examining the flight path, at no time did I go into or near a restricted zone.

To view my flight, go to:
https://app.airdata.com/share/NbaXqv

At approximately 1m40s into the flight I lost the connection between the controller and the Mini, despite the flight log indicating a 100% radio signal and being <500' from the Mini. The flight log indicates I had 17 satellites at the  time.

I tried to reestablish the connection and by the time I did so at 1m45s, the Mini had instituted AutoLanding that I could not cancel. I immediately headed for the shore and luckily crashed the Mini at 21+ mph on to the land just 2' from the water's edge as it ran out of altitude. Glad to report no as yet discovered damage although she was quite dirty.

My question is: Does the Mini lose authorization to fly in an authorization zone if the signal between the Mini and controller is lost? If so, this is a serious design flaw.

I cannot answer your question, however the auto landing does not make any sense to me. There was plenty of battery and signal was good. Glad it did not sustain to much damage. Hopefully you contacted DJI.

Never heard of this one before, I would have thought loss of signal would just initiate Rth , it’s your craft that’s given clearance so you would imagine that clearance stays with the craft, but who knows,

hallmark007 Posted at 1-29 17:19
Never heard of this one before, I would have thought loss of signal would just initiate Rth , it’s your craft that’s given clearance so you would imagine that clearance stays with the craft, but who knows,

I've lost the signal in a non-authorization zone and it did initiate a RTH..That's why I think it must have to do with both loss of signal and being in an authorization zone.

FlySafe at DJI have been contacted.

FlySafe at DJI has been contacted

hallmark007 Posted at 1-29 17:19
Never heard of this one before, I would have thought loss of signal would just initiate Rth , it’s your craft that’s given clearance so you would imagine that clearance stays with the craft, but who knows,

Actually, it's the controller S/N you enter to get pre-authorization. not the craft number, so the loss of signal scenario makes sense.

Tandemist Posted at 1-29 17:34
I've lost the signal in a non-authorization zone and it did initiate a RTH..That's why I think it must have to do with both loss of signal and being in an authorization zone.

FlySafe at DJI have been contacted.

If it did initiate a Rth if gps signal was weak then it might land , but don’t think that’s it .

Can confirm this has happened to me too.

Once you lose that signal in an Auth Zone, have fun retrieving!

Hi Tandemist,

It looks like you only lost the video connection, as all data is written in the log.
After loosing video connection your craft went into a "AirportAvoidLanding" mode.

It should enter a RTH mode loosing video connection loss, guess its different when flying in an authorization zone.  Guess DJI don`t want a drone fly back on its own in a straight line in such a zone.

If so, should be documented. (well   i did not search for it, so mayby its written somewhere )

So good question for DJI to answer.

cheers
JJB

damn, this really sounds like it should be a big ass popup on the display when unlocking the authorization zone..... also makes absolute no sense not being able to cancel autolanding once connection is re-established...

This can be a problem to me. Where I used to fly my previous drone is an authorization zone for DJI, although for my Aviation Authority flight is permitted up to 30 m or up to the height of any man made or natural obstacle. This park is on the shore of a river and there is a big bridge with pillars over 100 meters high, I could fly up to 100 m if I stay in proximity of the bridge pillars.

I am afraid if I lose connection when I am filming the bridge (what I did several times with my previous drone) the Mini will auto-land in the river. Very scary.

I plan on performing a test.

I will take my Mini to an Authorization Zone and take off and fly it 500 or so feet away from the controller, then try to create a loss of signal (may have to turn the controller off). I'll report the results.

Since I have experienced a loss of signal in a non-authorization zone and had the Mini RTH, I don't think it's necessary to re-perform that test.

I will report my results to the forum. As well as any DJI Fly Safe response.

Thanks to all who have contributed to this thread.

UPDATE:
Tried the test I mentioned yesterday.

I took off and flew the drone in an authorization zone, Caused a loss of signal, reestablished signal, and the drone operated perfectly. I could continue to control it.

Next test. Same start then turned off controller. Then restarted controller, established connection with drone, answered all the questions for authorization, and the drone operated perfectly. I could continue to control it.

Third and final test. While drone was flying, I turned off  controller and never turned it back on. Drone waited about 30 seconds, then started an automatic RTH. Landed perfectly with no connection to controller or app.

WHY? Why did I have the failure yesterday, yet today the Mini operated exactly as one would hope.

I have a theory, as yet untested. When one unlocks an authorization zone at DJI Fly Safe, that License is connected to the account. Open the DJI Fly app, click on the three dots in top right, then under the Safety tab, scroll down to Unlock GEO Zone. Notice that there are two different licenses, one for the account and one for the Aircraft.

You can download the account license to the aircraft.

However, I think that the license on the aircraft needs to be switched on. If that switch is not on and there's a disconnect between the aircraft and controller, then the aircraft does not have a license to fly in that authorization zone and performs as I described yesterday - a forced AutoLanding.

But, if the switch is turned on, then the license is retained by the aircraft and it performs as described in my test.

Thoughts and comments encouraged.

Sounds like a decent theory, and one I might try myself this weekend if the wind allows it.

I don't think I did the FlySafe unlock the last time my Mini went awol, just the unlock on the app (actually I definitely didn't because after a lot of fighting with the drone a pop-up asking to unlock it appeared), so I'll do the FlySafe unlock and force a loss of connection too and see how I fare.

Tandemist Posted at 1-30 16:58
UPDATE:
Tried the test I mentioned yesterday.

Hm. How I understand it: When you create an unlock online, it shows up in the left tab of the app. You sync it to your drone and activate it (right tab). However, it's the same unlock and it's always tied to a specific AC. Because when you create an unlock online, you provide the SN of your AC's controller chip (SN is shown inside the app). You cannot take off AFAIK if the unlock is not synced to the AC. So I don't quite get your theory. But not sure if there's something I'm missing here.

The manual states during RTH if GPS signal is lost it hovers a while then initiates autolanding.

This sound like the WRONG message issue that affects some MM including mine. The MD (mobile device) reports loss of connection (RC to AC) but it is the opposite: RC still connected to AC and full in control, only the MD is not connected to RC. Unplug and plug back in the USB cable at one side fixes the problem.

I suggest you try this fix at the next occurrence.

Hello and good day Tandemist. I am sorry to read and to know what happened to your previous flight with your DJI Mavic Mini. It also good to know that you were able to retrieve the said drone and had no major damage on it. In addition since there was a crash that happened. I would recommend you contact our support team at  https://www.dji.com/support?site=brandsite&from=nav . We have the professional team who would do their best to find out the reason of the incident. Thank for your support.

I live in a Blue zone, and have flown it over hudred times since news years  eve, when we were able to unlock the zones, and most of multiple times have flown it to where the controller loses contact and initiate a return to home, and never ran into it autolanding,  it comes home every time,Tim

The answer to my original question, answered by DJI

"Thank you for your mail.

We got the confirmation from the technical department, the authorization/unlocking license will not be impacted when the signal between the drone and controller is lost.

1. Kindly update the DJI app, fly safe database version, the firmware of the drone and remote controller to the latest version.

2. Ensure the mobile device has a good internet connection and GPS satellites connected reaches more than 10."

So a BS reply.

I'm sure both your and my apps and drone were up to date, internet was fine and of course GPS sats at right levels.

BS, BS, BS. They don't know or want to ignore it.

This thing happened to me this evening also.

Autolanding in an Auth Zone, however I had clearance to take off and did a Auth Zone unlock on their website... so everything should be fine.. Flight lasted about 2 minuters. 86% battery left on my Mavic Mini,

Was supposed to get some sunset shots over the lake, at about 40-50 meters height the Mini just went into Auto-Landing sequence, it was way out over the lake so there was no chance of it making it back all the way to land before hitting the water surface and sink. And that's just what happened.

I couldn't cancel the auto landing sequence either, the cross on the phone saying "Tap here to cancel auto Landin" where just greyed out.. kept tapping and tapping and nothing.

Im going to try and retreive it tomorrow, but I wondering if anyone know where I can see the last flight? so I can see where it went down (GPS)..  I have the insurance from DVI so if I manage to get ahold of it , I guess I can use the insurance to buy a new drone cheaper.

Is this normal ?

Thanks,
/Newbie

It makes sense. You no longer have control of the drone in an Authorization zone so it lands where it loses connection. It's the least dangerous thing to do in those areas. Is it ideal? No, but you are flying in restricted airspace so safety is the priority.

22340179 Posted at 6-24 13:20
It makes sense. You no longer have control of the drone in an Authorization zone so it lands where it loses connection. It's the least dangerous thing to do in those areas. Is it ideal? No, but you are flying in restricted airspace so safety is the priority.

Yeah.. but I did have filed for the "DJI Self Unlocking" in the Blue Authorization Zone ... and I didn't loose the connection.. I could control the Mini all the time about 60-70 meters out.. so no connections losses.. I just didn't have the ability to cancel the auto landing sequence..

I think they should tell people "If you fly here, the drone will eventually go into auto landing .. and you will have no control to cancel the auto landing, so make sure you don't fly over any water or other hard-to-retreive areas.. "

its sunk here:

didnt quite made all the way back to the shore line.. tried in panic to redirect it to the small island, Im too much of a newbie pilot I guess..  

83% battery left until the end.

The directions for getting the flight records from your phone/tablet are on the page below.  

I'd be interested in seeing your logs too to see what the sequence was that led to it going down.  If you choose to upload your logs to the viewer, feel free to paste the resulting URL here so we can help you get details out of them.

Best of luck on your recovery efforts!

https://www.phantomhelp.com/logviewer/upload/

KlooGee Posted at 6-24 13:58
The directions for getting the flight records from your phone/tablet are on the page below.  

I'd be interested in seeing your logs too to see what the sequence was that led to it going down.  If you choose to upload your logs to the viewer, feel free to paste the resulting URL here so we can help you get details out of them.

Thanks,

It should be this one: https://www.phantomhelp.com/logviewer/I0J8ETSUDBDYDICLY80C/#

Here is another person that seems to have the same problem.. not connected to any Auth Zones or whatever.. Mini just goes into Auto Landing...

https://youtu.be/yMhchAJiT7g

This doesnt make sense to me at all...

NickeZ28

What a bum!

Now this may be a coincidence. However, like Einstein, I don't like coincidences.

My Mini went into Auto Landing mode at 1m45.1s after start. Your Mini did the same thing at 1m46.6s. That's virtually the same time after takeoff. Maybe there is something about that.

Unfortunately, problems of this sort are never experienced prior to it happening. It's not something that would be  shown in a simulator either. So stuff happens

I now know what to do should this happen again.

1. Recognize what's happening. And quickly.
2. Switch to S mode.
3. Go to full screen map mode.
4. Find closest land on map.
5. Turn drone so arrow is pointing to that land.
6. Full power forward.

Do not hesitate.
Do not try to return to home with control sticks.
Get to the nearest land!

I have no doubt that, assuming the winds were light, had you been able to recognize what was happening, given your altitude (177') and distance from home (300'), you could have made it. But of course, how would you know? I was lucky enough to get to a rocky shore and hit at 21+mph. I was only 50' up and still went almost 200' laterally. Very lucky. I lost 10s and 20' before I started moving the drone.
==========================================
Is it possible to prevent this? DJI says it's not supposed to happen.Yet it did.

I have modified my flying in Authorization Zones, which are abundant in San Diego.
1. Get and download the  auth code.
2. Takeoff.
3. Let the drone hover for at least 30 seconds to see if you get any additional messages on the display for you to respond to.
4. Only then start flying on your mission.
5. Fly nearby for a minute or two.

Tandemist Posted at 6-24 16:03
NickeZ28

What a bum!

Yeah, thanks.

I think I would have made it to land, if I completely realized what was about to happened. I was setting up the camera for a few shots just when it turn on the Auto Landing seq. The moments following I was too focused at trying to cancel the AutoLanding, there's a popup on the phones screen saying like "tap here to stop auto land" .. and that button on the phone where greyed out, so it wasn't an active pushable "button". Like it was in some sort of locked mode..

Then after a couple of 10-15 sec I guess..  Well, don't REALLY think I understood that it is actually gonna attempt to land.. there's no way... The best option would be that in auto landing it should go down and hover at about 1-2 meters alt. or something..

I was just lucky that I was fairly close to the shoreline as I was. I was on my way out when it happened, was just stopping for a few photos.

Given that I only have been flying for 5-6 times all in total, Im too much of a rookie to keep good focus on flying, specially when you know you have a countdown ticking...

I don't think this is a pilot error.. I will ask DJI Support to explain it to me, and also if it was pilot error, what did I do wrong?

This is really something for the NTSB and their investigators..

--

Now, the Auth Zone - I was just in the outskirts of .. its not an airport or no fly zones or something like that.. It belongs to Swedish Bofors who makes artillery weapons, and their testing grounds. And also combined with Swedish military testing grounds.

I was thinking they might have some jamming equipment that keeps drones from flying nearby there, still they post on their website that from august 1st 2017 its allowed to fly drones and also take pictures above these areas, just not at any security objects. Which there aren't any there, its a just a friggin lake. Its not allowed when they perform their tests though, but they close down the whole area then so you couldnt get in anyhow.

And - If the above is correct - They should mark the area a Restricted RED Zone - where there would be no self unlocks available.

------

Weather Conditions:

Calm nice beautiful sunny and clear evening. This is a photo taken with my cellphone. Really calm, hardly and wind at all. Around 25 C (77 F)



------

Anyway,

Im gonna attempt a search and rescue mission tonight, Ive got a boat and a like a net and see if I can find it and drag it up.  I did purchase it together with the DJI Refresh plan so IF I can find/retrieve it I guess I can use one of my DJI Refresh.

NickeZ28 Posted at 6-24 14:10
Thanks,

It should be this one: https://www.phantomhelp.com/logviewer/I0J8ETSUDBDYDICLY80C/#

Hiya,

In the log at start a message is written : " Authorization Zone. -fpv_nfz_before_takeoff_auto_landing_time_tipsAuto landing in 100s!"

this message is repeated and counting down to about 80secs.
At 1m46s an AirportAvoidLanding is performed, almost 100 secs after start of the flight.

At start the craft was in OPTI mode due to low reception of GPS.
10 seconds in flight GPS oke to set a HP.

Looks like that at start of the flight MM knows already that it will land after 100 seconds ??!!  uh ?

Hope that DJI will give the answers!   and good luck finding your drone!!

cheers
JJB

NickeZ28 Posted at 6-24 15:22
Here is another person that seems to have the same problem.. not connected to any Auth Zones or whatever.. Mini just goes into Auto Landing...

nope, this is a Uncontrolled Landing, probably due to power problems, still in a normal flight mode = CineSmooth.

Tandemist Posted at 6-24 16:03
NickeZ28

What a bum!

Hiya,

Another thing in common (your flight and NickeZ28) is that your flight as well was started in OPTI mode, after 14secs HP was set.

So when does the autorization is granted to the drone / rc ; before takeoff (if fully GPS connected) ?  if a drone is flying in OPTI or ATTI mode the 'system' does not know where the craft is flying...

When connected with GPS and already flying mayby the autorization is not acknowledged.

Just a thought....

cheers
JJB

JJB* Posted at 6-24 23:41
Hiya,

Another thing in common (your flight and NickeZ28) is that your flight as well was started in OPTI mode, after 14secs HP was set.

Perfect thanks, I can't see the columns "Error Info" "Warning Low" "Warning High" when I open the log files.. but there's a whole bunch of info there.

As far as I know (Ive tried flying over the same one time before, that time it didn't allow me to even take off. So in normal circumstances the Auth Unlock should take place before take off. My cell phone reception was fair (2 out of 5 on 4G), so it would have picked up the unlock if it does so over internet connection ..

But I wonder why it issued the "AirportAvoidLanding" at 1.46 .. that's when it started to descend.. There are no airports within kilometers/miles that I know of.  OR.  Is this the way they handle unauthorized drones in auth.zones ?  If there was something wrong with the Mini picking up the Unlock in the beginning.. still.. then it would have kept me from even taking off..

And in normal flying mode, you can always cancel the Auto Landing seq. right? that's started counting down from 100 seconds ? in mid flight?

NickeZ28 Posted at 6-25 00:07
Perfect thanks, I can't see the columns "Error Info" "Warning Low" "Warning High" when I open the log files.. but there's a whole bunch of info there.

As far as I know (Ive tried flying over the same one time before, that time it didn't allow me to even take off. So in normal circumstances the Auth Unlock should take place before take off. My cell phone reception was fair (2 out of 5 on 4G), so it would have picked up the unlock if it does so over internet connection ..

hi,

"As far as I know (Ive tried flying over the same one time before, that time it didn't allow me to even take off. So in normal circumstances the Auth Unlock should take place before take off."

That means when GPS signal is there, you need to have permission to start a flight. But when flying away from the spot in OPTI mode....no permission is needed, as the system does not know that its flying in a NFZ.

In OPTI / ATTI  mode you can go fly everwhere, so also in NFZ etc.

Why a countdown for a AirportAvoidLanding ? must be a general message for landing in a NFZ or so.

Normal landingscan be cancelled, critical low batt landing and this type of landing not (both safety landings)

Let`s see what DJI will tell you

cheers
JJB

JJB* Posted at 6-25 00:32
hi,

"As far as I know (Ive tried flying over the same one time before, that time it didn't allow me to even take off. So in normal circumstances the Auth Unlock should take place before take off."

Thanks, I didn't know about the OPTI mode.

On my next Mini, I would like to turn that off. So there will be no confusion wether its flyable or not.. over NFZ or not ..

Is it possible to turn off/at least so it doesnt allow take off before getting GPS signals ?

NickeZ28 Posted at 6-25 01:13
Thanks, I didn't know about the OPTI mode.

On my next Mini, I would like to turn that off. So there will be no confusion wether its flyable or not.. over NFZ or not ..

Hi Nicke,

No   you cannot turn it off.

GPS-P, OPTI, ATTI.  In that sequence (and v.v.) when loosing GPS signals. If enough light and low in height drone in OPTI mode, it OPTI not possible than ATTI mode.

It is all in the manual....

Always check before flight a) compass check and b) enough SATs (so in P-GPS mode)

In the DAT file of this flight mayby more info, its the file FLY015.DAT (on your mobile device too   MCDarFlightRecords map), if you like post a link to that file on here.

cheers
JJB

What JJB is saying is you flew the drone before it locked onto satellites. When you started the drone you literally took off right away according to the log. If you fly before locking in gps sat’s you can have problems like home point being set in the wrong spot or problems in authorisation zones. You have to give the drone some time to recognise where it is. It gives you a warning about flying before this up the top of the app screen.

JJB - you have explained the similarity between the two flights. The same 100 second timer was running. I am absolutely certain that on my flight there was no warning on the screen. That sounds like a design fault. Something this serious should have bells, whistles, haptics.

NickeZ28 - Please give us update on your recovery attempts. Good luck. I agree that it was not pilot error, but problems with the warning system and DJI's failure to properly warn us, and to not provide a preflight checklist.

Thanks to everyone who contributed to this discussion. I've learned so much.

AirportAvoidLanding

There are several ways to interpret this.

"Avoid Landing here as an Airport is nearby" is one possible interpretation. It happens to be an incorrect one.

"In order to avoid an airport, the drone is landing" is the correct interpretation.

However, that warning was never presented to the pilot in these two cases. The way it is presented indicates that it was something to put in the log, not something to be presented to the pilot.

I found this in another thread titled "What happens when you enter an Authorization Zone mid-flight?"
https://forum.dji.com/thread-127 ... will%20not%20hover.

"Yes, the drone is not able to take off when it is in the NFZ or authorization zone without unlock. If the drone takes off and enters an authorized/No-fly zone accidentally when the GPS signal is weak, it will be forced to land when the drone acquires enough GPS signal, it will not hover. During the landing, other sticks will still work except throttle. It will not RTH.
Please follow the drone restriction and keep a safe flight."

It appears that taking off in an AuthZone before the GPS has acquired the sats has exactly the same effect as taking off outside an AuthZone and entering it.