Hello,I've flown my mavic for a month now without any issue. But on the 24th of February, I took it out and my mavic sort of flew away. Fortunately I was able to get it back within a minute. This is what happened. The mavic was flying perfectly normally, when the DJI Go App crashed. It happened to me before so I wasn't really worried. But then it started to connect and disconnect 7 or 8 times in a row. And then the mavic wasn't responding anymore. The controller disconnected from the aircraft and the mavic started to blink yellow and went high up in the sky, not sure by how much. And started to fly away. So I disconnected the phone (Nexus 6) from the controller and started to run behind the drone. I finally connected with it and flew it back in my garden. Hopefully it didn't hurt anyone and the drone is safe without any damage. But I don't know if it was my fault or mavic's one. On the DJI app, I have the flight logs of just before it flew away, and just after, when I landed. I think this is weird.
Before flying I did the update and an IMU calibration. And looking a the DJI Go App flight logs it seems that the Home Point wasn't at the Take Off point, but it seemed to me that it had been correctly setted.
There are the flights logs from that day : http://healthydrones.com/main?share=UsDeDw - http://healthydrones.com/main?share=GJnzoi
And this is the footage when I reconnected with the drone and landed :
I've flown several times in my garden without any issue.
I haven't fly again, I'm a bit worried. I don't know what to do. Should I send my Mavic's and controller's flights logs to DJI ?
Hope you can help me.
Thanks

Mee

Sorry can't help, but out of interest why did you do an IMU calibration?

You lost radio control, and your app crashed, I think the reason you might be loosing RC is something is blocking your signal maybe that big house ,

I don't know about your phone but I've read other instances with the same phone and the app crashing.

I also think your envoirment is not the best for flying I class D warning and also you had high velocity wind warning.

Well done for getting your Mavic back safely. Good luck..

IMU : I read somewhere that when you were changing the environment where you where flying you should do a full recalibration. I went to the mountains last week I've recalibrated it there, and when I came back home.

The fact is that I've lost control of the mavic when it was in front of me, 10 meters away from me and with line of sight.
I flew several times here and never had any issues, (other than the app crashing).

I know about the class D area, but I fly only over my garden and low altitude...

Mee Posted at 2017-2-25 15:13
IMU : I read somewhere that when you were changing the environment where you where flying you should do a full recalibration. I went to the mountains last week I've recalibrated it there, and when I came back home.

The fact is that I've lost control of the mavic when it was in front of me, 10 meters away from me and with line of sight.

As the Manual clearly says don't calibrate unless you are prompted, although I don't think this had any bearing on what happened.

Something blocked your signal and you obviously had a problem with app crashing..

I'm sorry to hear. If you haven't done so already, it would be best to contact the Europe Support Center to have the logs evaluated for a potential warranty claim.

My take.

The app crashing?
Thats easy, dji hasnt yet perfected the app for every phone, android seems more prone to crashes sadly.

Reconnect issues?
There where early reports of this to some degre, could be junk in your usb port on the phone, from being taken inn\out of your pockets etc
Also some complain about the quality of the bundled cable.
And there is the odd report of it sometimes just faling out if you have it seated in the little plastic retainer in the controller.

Fly away?
This one is also easy and partialy your own fault even if its realy not.
Controller uses your phones gps to sett home point if it is user selected after takeoff, im gonna guess you have one of the small shoulder buttons assigned to this and accidently triggered it.
Phones gps are sometimes way behind on uppdating, atleats thats what the research on the matter shows so, your homepoint then is somewhere far away and you loose rc link probobly cause of the house
mentioned earlyer, mavic takes off and does what it is supposed to return home.
We can argue all day if this is a problem with dji's app and rth algorythm but i think partial blame is to be put on the phone AND user. A loud comfirmation off homepoint change could maybe
trigger pilot to investigate beefore accidents happen.
OR maybe this is a genuine bug who knows.

As to the running after it, I am going to assume you didnt try to cancel rth or press the pause button?
IN that case theres your answer.

I minght be totaly wrong ofc, but thats my take on it.

Are you using the "DJI Go" app or "DJO Go 4"? I have heard of home points that have been placed far away due to a bug in "DJO Go". If that was the case for you, the drone was probably on the way to a false homepoint due to the disconnect.

You should pull the log from the internal Mavic drone flight recorder memory using the DJI Assistant software. It has a LOT more information than the telemetry data that is sent to your phone/tablet.  There are some tools on the web for interpreting them, as well as helpful experts at the mavic pilots forum (find BudWalker or msinger).

Thanks for all your answers.
I was using the DJI Go 4. And I have the memory that the Home Point was well recorded, I heard the voice telling me that "The Home Point as been updated".
I have no button assigned to set a new Home Point, so the Home Point was the one recorded by the Mavic at take off. I even waited few seconds hovering above take off to be sure that the home point was well recorded. And when the RTH initiated, I couldn't cancel it, because the controller wasn't connected with the drone.
For the Home Point being recorded a bit behind, when I look at the Flight Log on the App, the Home Point seems indeed set behind the house. Somewhere I've never flown... Is there a way to be sure of where the home point is when taking off ?
About the house blocking the signal, I was in front of the house, just like the drone, almost enderneath the drone, so there were nothing, absolutly nothing between the controller and the Mavic, and the antennas were well deployed.
I don't know of it can be useful, but here are the .txt flight logs from the phone : http://www.phantomhelp.com/LogViewer/9JL55CTR4UEV42DIPR29/ - http://www.phantomhelp.com/LogViewer/QNL2MGTNLZFRL6DE6V26/
I'll post my flight logs on the Mavic pilot forum, to see if they can find anything, I'll also send them to the DJI support.

Thanks again

Mee Posted at 2017-2-26 08:14
Thanks for all your answers.
I was using the DJI Go 4. And I have the memory that the Home Point was well recorded, I heard the voice telling me that "The Home Point as been updated".
I have no button assigned to set a new Home Point, so the Home Point was the one recorded by the Mavic at take off. I even waited few seconds hovering above take off to be sure that the home point was well recorded. And when the RTH initiated, I couldn't cancel it, because the controller wasn't connected with the drone.

What is on that roof you were flying over it looks like a lot of metal or lead or something?

The roof is made of zinc, but I didn't go above the roof, even if the map from the flight log seems to say so. It went above the roof by it self, as in the video. But I've never flown above the roof "on my own". And when the connection was lost, the drone was far from the roof.
Do you think that the roof can disturb the connection even if the drone and the controller were not near the roof ? It seems weird.

Mee Posted at 2017-2-26 10:11
The roof is made of zinc, but I didn't go above the roof, even if the map from the flight log seems to say so. It went above the roof by it self, as in the video. But I've never flown above the roof "on my own". And when the connection was lost, the drone was far from the roof.
Do you think that the roof can disturb the connection even if the drone and the controller were not near the roof ? It seems weird.

Well zinc is not a ferromagnetic metal so it should be ok , but for me I would keep away from it.

Mrimstad Posted at 2017-2-25 23:16
My take.

The app crashing?

"Controller uses your phones gps to sett home point if it is user selected after takeoff, im gonna guess you have one of the small shoulder buttons assigned to this and accidently triggered it."

@Mrimstad - Even though @Mee has already replied and clarified that he/she did not manually set the Home Point, I just want to point out, for the benefit of others, that what you said here is not exactly accurate. If you choose to manually set the Home Point, you can choose to set it to the current position of the aircraft, or of the RC/phone. It will not default to using the RC/phone.

Also, I could not find any option to assign "Reset Home Point" to any of my RC buttons on GO v4.0.3 on Android.

Mee Posted at 2017-2-26 08:14
Thanks for all your answers.
I was using the DJI Go 4. And I have the memory that the Home Point was well recorded, I heard the voice telling me that "The Home Point as been updated".
I have no button assigned to set a new Home Point, so the Home Point was the one recorded by the Mavic at take off. I even waited few seconds hovering above take off to be sure that the home point was well recorded. And when the RTH initiated, I couldn't cancel it, because the controller wasn't connected with the drone.

"For the Home Point being recorded a bit behind, when I look at the Flight Log on the App, the Home Point seems indeed set behind the house. Somewhere I've never flown... Is there a way to be sure of where the home point is when taking off ?"

@Mee - If the Home Point in the logs looks incorrect, then I'm afraid it sounds like the Mavic did not have a good enough GPS lock at the start of the flight, and recorded a slightly inaccurate Home Point. It's advisable that when the app tells you that the HP has been recorded at the start of the flight, you should take a good look at the map and see if seems like the HP is in the right place. You might even want to click on the map to enlarge it if you can't quite make out the details on the small map.

So, if the HP was indeed recorded incorrectly, then the "fly-away" does actually sound like it was not a malfunction at all. It sounds like the Mavic lost communication with the RC and initiated RTH. That would explain the sudden gain in altitude, and then the Mavic flying in another direction (to the phantom Home Point).

Now, none of this really explains why you had such issues with the app and the RC losing connection in the first place.

Jason Lane Posted at 2017-2-26 10:53
"Controller uses your phones gps to sett home point if it is user selected after takeoff, im gonna guess you have one of the small shoulder buttons assigned to this and accidently triggered it."

@Mrimstad - Even though @Mee has already replied and clarified that he/she did not manually set the Home Point, I just want to point out, for the benefit of others, that what you said here is not exactly accurate. If you choose to manually set the Home Point, you can choose to set it to the current position of the aircraft, or of the RC/phone. It will not default to using the RC/phone.

I will be honnest and say i just assumed you could bind one of the buttons to it. Would make sence if you ask me.
On the other hand, close to no one will bind theyr new homepoint to where the craft is unless there is a werry specific mission that requires it.
My points are still valid as far as i can see. Just that you can choose doesnt make the first one wrong.Although poor gps lock at startup and bad set homepoint sounds way more likely.

There was a warning few week ago to swith to newer firmware (which is downoadable only through Apple application, Android ignores it) Latest firmware has fix for lost communication/go home issue. If you have latest firmware, I believe, it's version 3 or more, then most probably firmware needs more update. Please, send your log to DJI, they may need it to address this issue