I was at my office checking on the building and it was a nice quiet morning so I pulled out the mini for a flight. Pre-flight checks were all good. Booted up the mini and the controller, everything looked good.

I started flying, everything was fine. Went up and over the building, came back, flew around some more and I was about 100' up and a few hundred feet away when the DJI Fly app went black. The message said something in red, I immediately check the controls, but the mini is still responding properly. I try rebooting the Fly app...nothing. So I fly it back and hand catch. Unplug the phone from the controller, kill the app again, reconnect and restart the app and it's connected again. Then it also wants a compass calibration (either because I set the mini in the car or because of my Apple watch, I think I caught it with the hand that has my watch), but I put it back up, kept it low for a few minutes just to make sure everything seemed fine, and from that point on everything was normal again.

I haven't flown much yet, I've only had my mini for a few weeks and I'm not able to fly anywhere near as much as I would really want to (then again who is unless you do this for work or you're retired), but I'm curious as to how often this kind of issue happens to others and how they deal with it.

Just in case it's important:
- DJI Fly App version 1.1.3(88) - latest for iOS as of the writing of this
- iPhone 11 iOS Version 13.5.1

Hello there. I am sorry to know that you are having issue with the DJI Fly application. Can you please try to fly in a different location to see if the problem persists? Also, I will highly recommend you to fly in an open space away from any possible interference since the location that you are flying might have WiFi interference. Strong magnetic interference might cause some disconnection issues. Please keep us posted. Thank you.

DJI Stephen Posted at 6-18 23:04
Hello there. I am sorry to know that you are having issue with the DJI Fly application. Can you please try to fly in a different location to see if the problem persists? Also, I will highly recommend you to fly in an open space away from any possible interference since the location that you are flying might have WiFi interference. Strong magnetic interference might cause some disconnection issues. Please keep us posted. Thank you.

DJI Stephen,

thanks for the reply.  Wifi interference would cause the phone to disconnect from the controller?  I would understand the drone dropping connection from the controller in a heavily polluted wifi area, but I don't understand how the app would lose communication with the controller.  Maybe I didn't explain myself well in my original post.

What if that happen and your drone is not in visual? scary huh? since you would not have a visual from the phone, it would be hard to see where the drone is going etc..only option would be Return home I guess.

Welcome to the forum there... be aware that flying from a building is one of the known reasons to be a candidate for fly-aways (drone loss). Be sure the power the Mini outside any magnetic interference in your building, if you're unsure do not fly. You can verify the magnetic field and orientation with a mobile phone but you need to know what you're doing.

Wi-Fi interference still happens but the 5.8 GHz used for FCC is usually outside the reach of typical home and office routers. I ignore the sources of other 5.8 GHz emissions but in my country I tend to rely on the 5.8 GHz range despite the shorter throw because it proved to be less influenced by home Wi-Fi usage and in a clearer frequency spectrum.

m80116 Posted at 6-19 10:17
Welcome to the forum there... be aware that flying from a building is one of the known reasons to be a candidate for fly-aways (drone loss). Be sure the power the Mini outside any magnetic interference in your building, if you're unsure do not fly. You can verify the magnetic field and orientation with a mobile phone but you need to know what you're doing.

Wi-Fi interference still happens but the 5.8 GHz used for FCC is usually outside the reach of typical home and office routers. I ignore the sources of other 5.8 GHz emissions but in my country I tend to rely on the 5.8 GHz range despite the shorter throw because it proved to be less influenced by home Wi-Fi usage and in a clearer frequency spectrum.

m80116,

Thanks for the welcome.

I wasn't flying from a building, I was at my work, went outside (away from the building) and went flying.  I was a good 50-100' from the building itself.  I ensured there was no compass interference, I kept the drone "low" 30 feet or so and less than 50 feet away and did some pre-flight checks to ensure everything was responding properly, that the map showed the proper orientation and location, that the controller inputs were the direction and speed I expected, etc.  

I understand about wifi & magnetic interference between the controller to the drone.  That makes 100% sense to me.  What I didn't expect was the app to say that it had lost communication with the controller.  The app view screen went black, the rest of the UI was there, but not really responsive. Killing & restarting the app did not help, though it's possible I didn't give it long enough to re-estabilish communication with the drone.  I have to admit, I was fairly uneasy flying "blind" and as such took great care to fly directly back and land so that I could try to determine where things went wrong.  Unplugging my phone and plugging it back in and then restarting the app seems to have been the solution, I was just curious if this suggests that there's a possible problem with the controller, the cable or just an oddity that happens with the app sometimes.

I think restarting was the plausible solution as this looks to me an app problem. As long as you make sure to set your RTH altitude according to your environments especially if you go beyond LoS you can always long press the RTH button on the RC or let it happen (verify having set your Signal loss for RTH unless you need some other option). I have seen cases where the Fly app wrongly announced an AC to RC connection lost (while it was only an MD to RC) but you could still trigger RTH as the RC was connected and the Fly app, despite unliked from the RC, was still responsive (hardware fault, rather than software).-
Lexicon: RC = Remote Control; MD = Mobile Device; AC = Aircraft; RTH = Return to Home; LoS = Line of Sigth

m80116 Posted at 6-19 11:10
I think restarting was the plausible solution as this looks to me an app problem. As long as you make sure to set your RTH altitude according to your environments especially if you go beyond LoS you can always long press the RTH button on the RC or let it happen (verifying having set your Signal loss for RTH unless you need some other option). I have seen cases where the Fly app wrongly announced an AC to RC connection lost (while it was only an MD to RC) but you could still trigger RTH as the RC was connected and the Fly app, despite unliked from the RC, was still responsive (hardware fault, rather than software).-
Lexicon: RC = Remote Control; MD = Mobile Device; AC = Aircraft; RTH = Return to Home; LoS = Line of Sigth

I always make sure to set my RTH properly.  I did a LOT of research before getting my first bigger drone (kind of funny saying that about the Mavic Mini, but I think you get what I mean) once I'm at my flying site.  I'll fly around to understand the height of things and then set my RTH height +50 or more depending on wind, the obstacles, etc.

My main thought of hardware fault was the cable from phone to controller, but after a restarting and reseating the cable in the phone it seemed fine.  I flew it indoors yesterday for about 20 min and had no issues either, so maybe it was just one of those things.

NONE of the DJI cables provided w/ my Mini worked: my OTG was causing intermittent disconnections, my USB for charging loses electrical connection if I push the connector, my spare one (barely ever used) does the same thing just in one direction (push) only. Using quality cables for charging: you could swing the charging station and it would NOT disconnect. Besides the RC USB receptacle is a very poorly and loosely fitting one.

Yesterday I lost my DJI Mini SE due to this issue. I answered a phone call and my phone screen went dark and when I hung up the call I had lost connection to my drone and never regained connection ever again. Also I was not able to recover it from the home point, it seems like it never came back.

onlinespawn Posted at 1-31 08:10
Yesterday I lost my DJI Mini SE due to this issue. I answered a phone call and my phone screen went dark and when I hung up the call I had lost connection to my drone and never regained connection ever again. Also I was not able to recover it from the home point, it seems like it never came back.

Cheap tablet just for droning would be the solution

Did you try just disconnecting and reconnecting the cable?

Hello I got the same problem. When I am flying my mini se. After a view minutes the app give a pop-up and says: lost connection with aircraft.. etc. But my mini se reacts on my remote! But I don’t have a live view on my phone. Then I disconnect and reconnect the cable, and the view om my phone is back.. but after a view minutes come the problem back.