On a recent flight, I was descending, with only descent input and the Mavic mini began rapidly flying backward in addition to down. Approximately 20-30* angle from level rearward and down. I am able to recover it with input, return to hover, and retry descent and it has happened again. After re-orienting the drone to my intended descent area, the problem disappeared and I was able to land without problem. I was not able to diagnose any problems at the time. EDIT: The only warning encountered was a propeller over speed error on a previous flight..

I had thought I noticed it a few other times previously, however, I had mistakenly dismissed it as pilot error. I just re-verified the intermittent problem at a separate location and with new propellers on the aircraft. Only descent input and drone flew rearward and down approx 20-30*.  I "think" it might have flow forward with upward input during the recovery this time, but I have not reverified.

There are no other malfunctions present that I am aware of. Prior to the latest verification flight, the propellers were replaced with new DJI propellers from Best Buy that were from a sealed in a hard plastic lock case at Best Buy.

Is there any know problems that could cause this? Solutions?

Hi Effie Marie,

best is, if you like, to share your log for this flight.

use this link > https://www.phantomhelp.com/LogViewer/Upload/

Post the upload link on here ; log mayby explains what happend.

cheers
JJB

Check, using the old propellers, if the problem persists.

Indoors i.e.in windless conditions, try a short, fully-automated hover flight of maybe two minutes, do not use the sticks.

If you know how to do it run the DAT file of the flight through CsvView and have a look at  the motor speeds chart, the motor speeds should all be reasonably similar though the rears will probably be the slightly faster as they apparently carry more weight. Take a screen shot of the chart and post it either here or on mavicpilots.It would also be useful to post the original DAT file .....if you can. The link JJB posted tells you how to get the logs.

That said, how are you judging that the drone is moving backwards?

Sean-newbie Posted at 11-8 13:24
Indoors i.e.in windless conditions, try a short, fully-automated hover flight of maybe two minutes, do not use the sticks.

If you know how to do it run the DAT file of the flight through CsvView and have a look at  the motor speeds chart, the motor speeds should all be reasonably similar though the rears will probably be the slightly faster as they apparently carry more weight. Take a screen shot of the chart and post it either here or on mavicpilots.It would also be useful to post the original DAT file .....if you can. The link JJB posted tells you how to get the logs.

The problem is literally, I was trying to descend straight down to land and it moves at or near full speed back as well. I'm able to recover and/ or compensate because I used to fly 3D helicopters like the trex so I fly intuitively and could land while fighting the errant drone.

This happened during a verification flight indoors last night, but it wasn’t ideal conditions to document because it was dim lighting and went into attitude mode. So, it isn’t a control scenario. The other situations were outside in clear conditions.

I will run the files. I have to rebuild my pc to get technical with files and such though as I’m on iPad/iPhone only at the moment.
I will attempt to duplicate again and keep track of the flight file.
I honestly think it's a firmware/software issue as it started giving me trouble after deleting the app and the app had been updated by the time I reinstalled it. Since moving to a more up to date app, communication distance has significantly decreased as well

I calibrated the controller today and did 1 15 min flight, but couldn't duplicate the error even though I tried to put the drone through various similar situations and the last location of failure.

Oh, the problem was indoors?

Cients Posted at 11-8 15:40
Oh, the problem was indoors?

Outdoors, then occurred indoors after replacing propellers. I’m going to hold off till I can duplicate it again  and keep track of the flight.

Did you try to replace the new propellers and check with the old ones?

There are two things that have been problematic with the Mavic Air 2 & Mini 2:

DJI Fly app version 1.2.0 - the update caused video connectivity to become unstable, lag and freeze.  In addition the stick commands were not accurate and caused the Mavic Air 2 to respond errantly to the commands.  - Fix: As per DJI Support delete the DJI Fly app and reinstall it.  This resolved the problem for me.

Remote Control firmware -
11/5 update - added support for Mini 2
11/7 update fixed problems with the firmware released on 11/5

Disregard the indoor flight it has no bearing, my mini flies perfectly indoors providing the area is well lit but, since it is relying on visual positioning alone to control things, dim light robs it of visual positioning and it can go bananas.
The reason I suggest the check flight is that you mention an over speed error. That is often associated with warped propellor blades that give less lift than they should at a given speed, hence the motors have to turn faster to give the appropriate lift. The check flight is a means of comparing the 4 motor speeds, a motor with significantly warped props givng reduced lift will stand out.

I ask  again how do you know it was flying backwards during the descent?
Simple tilt does not mean it is moving relative to the ground, it could be fighting wind that you do not know about. Vertical flights over head often look distorted because the observer is a not ncessarily directly under the drone nor are they necessarily looking absolutely vertically. I face this problem with virtually every take off and landing at the front of my house, the drone has to climb to at least 15m before it can be moved in a horizontal direction and if I want to fly beyond the house the necessary climb is 25m, ditto descents. From my perspective every such climb and descent looks to have significant horizontal drift.
I am not saying that your mini is not drifting but it would be better to tell us what makes you think it is e.g. is the indicated distince undergoing significant change?

Sean-newbie Posted at 11-8 18:24
Disregard the indoor flight it has no bearing, my mini flies perfectly indoors providing the area is well lit but, since it is relying on visual positioning alone to control things, dim light robs it of visual positioning and it can go bananas.
The reason I suggest the check flight is that you mention an over speed error. That is often associated with warped propellor blades that give less lift than they should at a given speed, hence the motors have to turn faster to give the appropriate lift. The check flight is a means of comparing the 4 motor speeds, a motor with significantly warped props givng reduced lift will stand out.

To respond to the question about how I know if it was flying backwards, it is because I was trying to land it vertically  down in a open street while looking through the screen and it flew backward into a group of trees at full speed.

Previously, I was watching it descend and it started moving rearward into a mountain.

In tHe indoor flight. I was standing in front of it attempting to land it and it almost flew into a table.

It is not a subtle or confusable error. It’s dramatic rearward and down. Like motors or props  are out, however, I replaced the props prior to the indoor flight that confirmed it previously.

I did another indoor test and just let it hover for several minutes using the visual flight positioning system With no input and didn’t notice anything extraordinary. It seems to occur after real world slightly enthusiastic flying and only at the end, when I am bringing it back in to land.

I will test tomorrow if the wind is down.
I am on app .1 not .2. I noticed my video feed range and entire communication system dramatically decrease when I had to update. I had zero errors before updating to that version of the app, so I'm even more worried about going to 1.2 from what I've read. At least I know what I'm working with here and have. Been through it and am able to recover. Possible separate different problems on a new versi9n might not have the same save rate

Effie Marie Posted at 11-8 22:42
To respond to the question about how I know if it was flying backwards, it is because I was trying to land it vertically  down in a open street while looking through the screen and it flew backward into a group of trees at full speed.

Previously, I was watching it descend and it started moving rearward into a mountain.

Hi Effie,

If only you put your flightlog for that backwards flying on here....
Will stop the guessing what really happend.

Flightlog to be found on your mobile device.

cheers
JJB

Here is the flight log of a recent flight. Once put into sport mode, no input other than up and down was made. I videos this flight with my free hand that normally controls the right stick. Viewing the flight, it looks like when the up and down input is made, it is also sending forward and reverse signals.

https://www.phantomhelp.com/LogViewer/3FR6Z8ZSYQKWYYJJJN8A

Here is the verification video of this exact flight showing I’m not adding any input except up and down and the mini is adding forward and reverse commands on its own. I’m filming with a second device in my right hand so no input on right stick

https://youtu.be/C-ApGzDdDJo

JJB* Posted at 11-9 00:10
Hi Effie,

If only you put your flightlog for that backwards flying on here....

Hey, can you take a look at the Info, log and verification video  I posted Above. Seems like you might be s as how to understand the logs better.

It is showing stock input for the tight stock, but you can see, my hand isn’t even on the stick

The problem also happens in litchi

The log file clearly shows the right stick going full down/reverse when the left stick is pushed to down/descend. If you are really not doing this, I think it must be a defective controller or firmware. Looking again at the log file, the sticks are doing exactly the same thing in descent or ascent. In other words, when you press left stick down, right stick "goes" down too. When you press left stick up, right stick "goes" up too. A great benefit if your flightpaths are all at a 45 degree vertical angle ;-)
Perhaps resetting the control mode would fix that.

GaryDoug Posted at 11-12 18:50
The log file clearly shows the right stick going full down/reverse when the left stick is pushed to down/descend. If you are really not doing this, I think it must be a defective controller or firmware. Looking again at the log file, the sticks are doing exactly the same thing in descent or ascent. In other words, when you press left stick down, right stick "goes" down too. When you press left stick up, right stick "goes" up too. A great benefit if your flightpaths are all at a 45 degree vertical angle ;-)
Perhaps resetting the control mode would fix that.[Image]

Literally, I posted a video of me holding a second device videoing this flight Which I posted the log of as well just using my left hand controlling the left stick. My right hand is holding a second phone videoing the whole flight

The fight stick was not moved during this flight. Maybe at takeoff. Because it took off forward and low.

I paused for about a minute to seperate out the flight to make sure it isolated and demonstrated the occurrences

I’m wondering if anyone else had encountered this or heard of it or knows what’s going on

Effie Marie Posted at 11-12 19:24
Literally, I posted a video of me holding a second device videoing this flight Which I posted the log of as well just using my left hand controlling the left stick. My right hand is holding a second phone videoing the whole flight

I’m wondering if anyone else had encountered this or heard of it or knows what’s going on

Yes, I saw that video. Have you tried what I suggested yet?

GaryDoug Posted at 11-12 19:26
Yes, I saw that video. Have you tried what I suggested yet?

I Recalibrated it after I After figuring out something was up.  That was last week.

Is there another way to flash it. I don’t have a pc right now

Effie Marie Posted at 11-12 19:30
I Recalibrated it after I After figuring out something was up.  That was last week.

Is there another way to flash it. I don’t have a pc right now

Not calibration, just change the controller mode from 2 to 1 and back to 2. This is just a WAG in case something in the setup got glitched. Otherwise, it looks like a bad controller in my opinion.

So it’s not propellers or anything like that. The flight log is showing right stick input mirroring the left stick Input

I think it’s happening in sport mode only

Effie Marie Posted at 11-12 19:34
So it’s not propellers or anything like that. The flight log is showing right stick input mirroring the left stick Input

Yes, it is mirroring the other stick. I suggested changing the setup because that is what the options are ...to swap stick functions. I wonder if somehow they got mixed.

There are other more experienced members here who will be along later to help. I was just doing a first pass at the problem. Good luck.

Effie Marie Posted at 11-12 16:14
Here is the verification video of this exact flight showing I’m not adding any input except up and down and the mini is adding forward and reverse commands on its own. I’m filming with a second device in my right hand so no input on right stick

https://youtu.be/C-ApGzDdDJo

Hi Effie,

i had to look twice to your video, mayby 3 times!

Using only left stick and your MM acends and descends and fly back and forwards.....uhhh??

cheers
JJB

Effie Marie Posted at 11-12 16:12
Here is the flight log of a recent flight. Once put into sport mode, no input other than up and down was made. I videos this flight with my free hand that normally controls the right stick. Viewing the flight, it looks like when the up and down input is made, it is also sending forward and reverse signals.

https://www.phantomhelp.com/LogViewer/3FR6Z8ZSYQKWYYJJJN8A

Hi Effie,

Never seen this before!

Your up / down and fore / aft move the same time same input.

See the chart, only in the beginning you see red and blue line are different, after that they are the same.
Blue spikes in the red line is where they differ just a little, so the red line after ID 160 is the red + blue line.

If your are using mode2 than Fore/Aft = Red and UpDown = Blue

Calibrate your RC and IMU ; if this persists then time to contact DJI

cheers
JJB

JJB* Posted at 11-13 00:22
Hi Effie,

Never seen this before!
[Image]

Is there a way to getting someone from dji on here to look at the logs or this topic? I see them respond to other posts. I just spoke with customer service and they just said to do things I’ve already done then they said send the drone in, but last time I sent a drone in for warranty they tried to not cover it under warranty and then tried to hold my drone unless I paid them to ship it back to me or paid for the repair

Effie Marie Posted at 11-13 07:45
Is there a way to getting someone from dji on here to look at the logs or this topic? I see them respond to other posts. I just spoke with customer service and they just said to do things I’ve already done then they said send the drone in, but last time I sent a drone in for warranty they tried to not cover it under warranty and then tried to hold my drone unless I paid them to ship it back to me or paid for the repair

Hi Effie,

Normally a DJI moderator joins a thread.....

Did you calibrate your RC and IMU (the only thing you can do), after that test flight your drone.

cheers
JJB

Rc, compass, imu calibrated. Rc switched between different control modes to see if that cleared the error. Error occurred today remote flying 3/4 a mile away . Glad I was able to catch it happening and correct with counter inputs
Contacted dji support and sent them flight logs and videos. They replied the next day asking for the flight logs and video, so I resent them.

Effie Marie Posted at 11-15 22:28
Rc, compass, imu calibrated. Rc switched between different control modes to see if that cleared the error. Error occurred today remote flying 3/4 a mile away . Glad I was able to catch it happening and correct with counter inputs
Contacted dji support and sent them flight logs and videos. They replied the next day asking for the flight logs and video, so I resent them.

Good luck with your case with DJI, guess your complaint its so obvious, software or hardware fault.

Really strange that it is not a hard failure, only after flying some time (your 3/4 mile away) this weird behaviour popsup...

cheers
JJB

JJB* Posted at 11-15 23:42
Good luck with your case with DJI, guess your complaint its so obvious, software or hardware fault.

Really strange that it is not a hard failure, only after flying some time (your 3/4 mile away) this weird behaviour popsup...

That sounds like a typical hardware intermittent, probably heat related. I see those all the time in my business. They can be very hard to isolate.

Just tested the remote with a brand new unactivated mavic mini. The problem was still present. Not limited to sport mode btw.

Then I tested my original mavic mini with someone else’s controller and the problem was not present

Then Switched back to my controller and the problem is present

The problem goes away with the slightest touch of the right stick, so it’s out of calibration, however, I’ve calibrated it repeatedly so it won’t stay or go into full calibration.
The problem is also present and shows up in the calibration procedure intermittently, even after recalibrating ineadiatly after a previous recalibration.

Dji is being unhelpful and not cooperating. And not responding to this post or doing anything with the service request Very unearving about buying one of the higher end drones like I was planning to.

Change the controller.

Cients Posted at 11-20 15:33
Change the controller.

That would be the logical thing for dji to do given that this is under warranty but they seem reluctant and are trying to get me to send the controller out of state, however, my state requires local warranty service be made available. The last time I send them a drone for warranty they tried to bill me for warranty work or wouldn’t send the drone back.

It very disapoijnting to see lack of cooperation or following c9nsumer laws by dji in regards to warranty, especially since I just bought dji care yesterday.

Here is a video clearly showing the defect Using the calibration in DJI Fly

Effie Marie Posted at 11-23 07:05
That would be the logical thing for dji to do given that this is under warranty but they seem reluctant and are trying to get me to send the controller out of state, however, my state requires local warranty service be made available. The last time I send them a drone for warranty they tried to bill me for warranty work or wouldn’t send the drone back.

It very disapoijnting to see lack of cooperation or following c9nsumer laws by dji in regards to warranty, especially since I just bought dji care yesterday.