Today I had a horrible experience that almost resulted in a fly away. I've had my Mavic 2 Pro for almost 3 years now and this is the first time this has ever happened.

I first noticed the gimbal had tilted upwards beyond the regular limit on it's own (while still on the ground & booting up) but figured I bumped the gimbal dial so I didn't think much of it. In addition to the tilting of the gimbal it also began to increase the exposure on it's own at this point. I had to manually revert it back to my typical setting and it remained there for a while.

The next issue I noticed was the drone seemed to pan one direction briefly on it's own during the middle of the flight. Again, I figured I must have bumped the controls again or the joystick got stuck. Then, after a few minutes later, as I was in a panning path the drone began to spin and drift all on it's own. Both the gimbal tilt and exposure issues occured at this time as well. I tried to manually recover it by moving the joysticks in every direction but it would not recover as it began drifting further away from my location. Fortunately, the Automatic Return To Home button still functioned and it brought the drone back to me.

After doing a quick power on/off cycle of the drone & controller + closed the DJI 4 app, I attempted another flight. This time, after maybe 30 seconds in the air, the same issues began again and the drifting felt way worse this time. Automatic Return To Home seemed to work but drifting still occured and had to fight the controls to get the drone back to me and land.

So far the only things I can think of that could have caused this interference (if it is considered interference) are:
1. Updated to latest firmware prior to flight
2. Had been within ~10' of a chainlink fence during compass calibration (take of site was limited)
3. Was near residential apartments so most likely WiFi was nearby
I've uploaded a snapshot showing how bad the spinning & drifting got at one point.

Any thoughts or suggestions on this would be great appreciated. Thank you

Hi there. Sorry for the trouble that this has caused. We recommend that you perform the IMU/Compass Calibration in an open location, away from any metals and possible interference. You may also update/refresh your aircraft's firmware via the DJI Assistant 2. In addition, kindly please try to fly to a different location for us to further isolate the issue. Should the same problem persists, it is suggested to send it back to our Service Center by reaching our Customer Support. Thank you for your continued support!

So far the only things I can think of that could have caused this interference (if it is considered interference) are:
Interference won't ever make your drone do odd things or fly uncontrollably.
At worst interference might swamp your control signal which would trigger RTH.

1. Updated to latest firmware prior to flight
That made no difference to anything

2. Had been within ~10' of a chainlink fence during compass calibration (take of site was limited)
No effect ... but why did you recalibrate the compass?
There's never any need to recalibrate the compass of your Phantom.


3. Was near residential apartments so most likely WiFi was nearby
See my first comment above.


I've uploaded a snapshot showing how bad the spinning & drifting got at one point.
What was the surface you launched from?
Post flight data if you want to find out more.

Labroides Posted at 6-13 22:03
So far the only things I can think of that could have caused this interference (if it is considered interference) are:
Interference won't ever make your drone do odd things or fly uncontrollably.
At worst interference might swamp your control signal which would trigger RTH.

Thank you for your response. The flight was launched on asphalt and I had recalibrated the compass because it always prompts me to recalibrate almost everytime I launch from a new location. It started requiring the compass callibration about 1 1/2 years ago but I couldn't figure out why.
I took my drone out again today but this time to an open field to recalibrate both the IMU & compass (surprisingly it didn't require a compass calibration this time). Afterwards, I launched it for a quick test flight and everything appeared normal again.

Still, I'm a little concerned because I don't know the real cause for the previous issues and do not want to experience them again.


I've attched the 2nd flight records file since that was a short flight and I would imagine it could be quick to spot some irregularities. I uploaded it to an online viewer but I couldn't see any irregularites myself but am unfamiliar.

Any additional thoughts/ideas on what could have caused the issues would be greatly appreciated. Thank you

On the second flight were you making all those turning and rolling motions with the remote controller? It looks like the drone is going a bit wild but maybe that was just you controlling it. If not, then I would suspect a problem with the controller, especially since you saw irregularities with the gimbal and camera controls and the M2P remote can control those.
Can you post the first flight log or a link to it?

GaryDoug Posted at 6-14 18:07
On the second flight were you making all those turning and rolling motions with the remote controller? It looks like the drone is going a bit wild but maybe that was just you controlling it. If not, then I would suspect a problem with the controller, especially since you saw irregularities with the gimbal and camera controls and the M2P remote can control those.
Can you post the first flight log or a link to it?

I didn't think of the controller. Great suggestion. No I wasn't making the turning & rolling motions - those were mainly all done on its own minus some which were me trying to take control.
Here is a link to the 1st flight: https://www.dropbox.com/s/nn9wyz26zg0vke6/DJIFlightRecord_2021-06-13_%5B12-05-10%5D.zip?dl=0

Thank you for your insight.

spacewalker60 Posted at 6-14 19:30
I didn't think of the controller. Great suggestion. No I wasn't making the turning & rolling motions - those were mainly all done on its own minus some which were me trying to take control.
Here is a link to the 1st flight: https://www.dropbox.com/s/nn9wyz26zg0vke6/DJIFlightRecord_2021-06-13_%5B12-05-10%5D.zip?dl=0

I see starting at about 13m 25s the controls are making some very active movements in both sticks, sometimes in unison. Unless you are really going crazy with the controls, that indicates a remote control issue to me.
This is what I would do: Find a large open area like a field. Take off in the middle if possible or at an end. Move only the up-down control and the forward-reverse (pitch) control and see what happens. Any other movement would be unintentional.
Perhaps JJB could load your files into his diagnostic app and show you the graphs of the control movements that the drone is "seeing".

GaryDoug Posted at 6-15 13:54
I see starting at about 13m 25s the controls are making some very active movements in both sticks, sometimes in unison. Unless you are really going crazy with the controls, that indicates a remote control issue to me.
This is what I would do: Find a large open area like a field. Take off in the middle if possible or at an end. Move only the up-down control and the forward-reverse (pitch) control and see what happens. Any other movement would be unintentional.
Perhaps JJB could load your files into his diagnostic app and show you the graphs of the control movements that the drone is "seeing".

Great suggestion. I'll try this out.

Thank you

Until JJB* can get here and do his magic, I tried to make some graphs with his app. They look interesting to me in that the pitch, yaw, roll values look to be identical or very similar at times. I have not seen anything like that in the graphs of my M2P. (Ignore the third black arrow in the first set of graphs)

Hi spacewalker60,

I had a look at your flight too. (the first flight).

Never seen this before in a log, but look at the RC input data ;
At the 'incident'  the Pitch and UpDn are becomig equal in values, same for Yaw and Roll.
During RTH still RC inputs in the log, but guess you did not touched the controls like this.
RTH did function oke, but height did increase from 56 to 72 meter (UP input did work), Pitch input, uh, not sure because drone was flying foward in RTH mode, so mayby Pitch forward speed it up a little.
Yaw and Roll had no effect.

I would do a RC stick and iMU calibration, check the next flights.

the other flight same issue, see data values in Pitch and Roll columns, they are more or less 'equal'.
Next, at 30 seconds, the 4 inputs, 2 + 2, are equal.

cheers
JJB

Hi JJB*,

I did an additional test flight after recalibrating the IMU & controller and everything appeared normal. I then decided to do a full flight and again everything was normal. However, during the next flight, I began to experience the same issues mid-flight.

After getting the drone home, I started to do some more browsing through the DJI app and discovered 1 of my 3 batteries had an inconsistent firmware because it hadn't prompted me to update it yet. I updated the battery then took it on another flight. This time, everything appeared normal again.

Do you guys think an inconsistent battery firmware could have been the cause of the mid-flight issues?

Thanks for all of your insight.

spacewalker60 Posted at 7-11 13:08
Hi JJB*,

I did an additional test flight after recalibrating the IMU & controller and everything appeared normal. I then decided to do a full flight and again everything was normal. However, during the next flight, I began to experience the same issues mid-flight.

That would be the most likely cause

Thank you Alvara74. I had a chance to fly it again today and everything functioned normally.

Thank you everyone for your insight.