Hello,
Yesterday I flew my new MM in the mountains with no issues. I then decided to take it out over a stream. I immediately notice that while hovering about 30ft in the air above the stream, the mini started drifting and would not hover. I pushed the stick to move away from the direction it was drifting and it did move forward and hover. I decided to fly it up stream and noticed that it was descending towards the creek. I left go of the controls so that it would recover but the drone continued to descend straight down towards the creek. I pulled up on the controls but the mini would not respond. I then attempted the return to home button but the drone was descending rapidly closer to the creek. I then attempted to push the drone forward and crash it into the shore. The drone moved forward but stopped and initiated "landing", which it did straight into the water and disappeared.
I had full GPS levels and battery. No wind and no warnings on the app. I posted the log for analysis if anyone is able/willing to figure it out. Can anyone tell me where the log is located on Android? I did email DJI to discuss this with them. I am waiting on a reply. Not sure why the mini descended or why would not respond to controls.
Thanks for the help.
Barry

Final video:
https://youtu.be/iPnAzVyzF5k

Log File for the crash:
https://app.airdata.com/share/SoCCTA

Please disregard the LOG location question. I located it.

The log file shows that a confirmed landing was in progress. It looked that way on the video also. Any chance you accidentally activated it?

Were you able to recover it from the stream?

GaryDoug Posted at 5-24 13:12
The log file shows that a confirmed landing was in progress. It looked that way on the video also. Any chance you accidentally activated it?

Were you able to recover it from the stream?

I was not able to recover it unfortunately.
The drone did announce "Landing" seconds before hitting the water. I was panicking at that point and attempting to get it to respond to anything. I cant say that I didn't initiate a landing at that point but it already descended on its own(without responding to me), to about a foot off the ground by the time I heard "Landing".

Ok, I just took another look at the log and it looks like the left stick was being held down all the time after 4 min 2 secs, altitude of 6 feet. It was still down until the "landing". Operator error or left joystick failure?

GaryDoug Posted at 5-24 13:22
Ok, I just took another look at the log and it looks like the left stick was being held down all the time after 4 min 2 secs, altitude of 6 feet. It was still down until the "landing". Operator error or left joystick failure?

Interesting. Is there any way to see if it was dropping before the left stick was held down?

Just examine the file you linked to Airdata and use the HD flight player. It shows the status of the sticks and several other parameters including altitude.


You can drag the little circle indicating time or just let it play...or both.

GaryDoug Posted at 5-24 13:38
Just examine the file you linked to Airdata and use the HD flight player. It shows the status of the sticks and several other parameters including altitude.

Ok thanks. I can't seem to find the HD player. I will keep looking.

B Mills Posted at 5-24 13:50
Ok thanks. I can't seem to find the HD player. I will keep looking.

I found the HD player but it doesn't show anything on the joysticks area unfortunately.

Here it is. I used your link. It shows full down and full ahead at that time

Here's a short summary of your flight data:
https://www.phantomhelp.com/LogViewer/VZ8CSSGYRA12RI0PC7PH/
It will give a lot more information than Airdata and you can view the joystick input.

Not sure why the mini descended or why would not respond to controls.
I can't see where the Mini failed to respond to your joystick input.
You were flying in Tripod Mode so the drone's response would have appeared slow, particularly with the drone 130 feet away from you.
Perhaps this gave you the impression that it was not responding?

But the reason it descended is no mystery.
At 4:01.6 you pulled the left stick full down and held it until the Mini had landed at 4:07.6

Sorry to hear about this.

Labroides Posted at 5-24 16:50
Here's a short summary of your flight data:
https://www.phantomhelp.com/LogViewer/VZ8CSSGYRA12RI0PC7PH/
It will give a lot more information than Airdata and you can view the joystick input.

Thanks for the info and link I will definitely check it out. I have been digging into the Airdata app to confirm what I actually saw. I did pull down on the left joystick at the end but it was because the drone was already dropping out of control and from what I saw the drone was already making contact with the water so I was thinking I could somehow cut off power and minimize the damage(I realize now it wouldn't have helped and would have been better off letting it continue to drop on its own). Just prior to pulling down I hit the RTH and it started beeping. I went to hold it down and realized it was already too late.
My main issue is that after I left go of the controls at 3:57.3 the drone continued to drop almost 2ft in 2 seconds according to Airdata Baro altitude. Sonar altitude showed it didn't move at all. Baro is closer to what I saw except for the Baro showed it was at 5.9ft when I hit the joystick down but visually it was actually just making contact with the water. The video shows how close to the water it was. I watched it drop straight down towards the water without touching anything.

There was another large drop earlier on while I was not touching the controls and I thought about bringing it back after I saw that and now I wish that I would have but I decided to do what I read in the manual to determine if the Downward Vision System was functioning. I pulled forward after the drop, allowed it to hover (which it did with no problem) and verified two blinking green lights.
At 3:34.3 without me touching the controls, the drone drops a total of 3ft in 7 seconds according to the Baro data.
I am new to drones but I thought they were more stable than this. I know the manual indicates many things that will mess with the Downward Vision System and that includes almost everything one might fly over(pure black surfaces like blacktop, tree limbs, water, etc). But I was under the impression that GPS would allow it to maintain stability if the signal is good. The signal was good in my case.

I don't know at this point. Maybe I am asking too much from the drone. Maybe the Mavic 2 has the stability that I am looking for. Not sure what to think right now. But again, thank you for looking for me.

Vlas Posted at 5-24 17:22
Sorry to hear about this.

Thank you Vlas, definitely sad and frustrating.

I don't understand why folks are saying you can't view the stick inputs on the Airdata site. I have no problem seeing them.

And the Airdata site shows 2 more parameters by default, an extra altitude reading from the ground sensor and the radio signal strength. And it has the option to play back the file.

Your video is only 5 seconds long. That is about the length of time the left stick was held down. The two methods of measuring altitude were in agreement, both showed a drop of 6-9 feet. It appears in the video that the drone was about that high at the begining of the clip. The numbers do not lie but sometimes our memory does ;-)

GaryDoug Posted at 5-24 18:33
I don't understand why folks are saying you can't view the stick inputs on the Airdata site. I have no problem seeing them.

And the Airdata site shows 2 more parameters by default, an extra altitude reading from the ground sensor and the radio signal strength. And it has the option to play back the file.

Thanks, yeah I ended up getting the joysticks to show. Not sure why it wouldn't at first. Seemed to be a refresh thing with my browser or something.

See my added comments above.

B Mills Posted at 5-24 18:46
Thanks, yeah I ended up getting the joysticks to show. Not sure why it wouldn't at first. Seemed to be a refresh thing with my browser or something.

Oh, that is a fault with the site I think. If you manually move the time indicator too fast, it does not update the stick displays. In that regard, the phantomhelp site works better.

B Mills Posted at 5-24 17:37
Thanks for the info and link I will definitely check it out. I have been digging into the Airdata app to confirm what I actually saw. I did pull down on the left joystick at the end but it was because the drone was already dropping out of control and from what I saw the drone was already making contact with the water so I was thinking I could somehow cut off power and minimize the damage(I realize now it wouldn't have helped and would have been better off letting it continue to drop on its own). Just prior to pulling down I hit the RTH and it started beeping. I went to hold it down and realized it was already too late.
My main issue is that after I left go of the controls at 3:57.3 the drone continued to drop almost 2ft in 2 seconds according to Airdata Baro altitude. Sonar altitude showed it didn't move at all. Baro is closer to what I saw except for the Baro showed it was at 5.9ft when I hit the joystick down but visually it was actually just making contact with the water. The video shows how close to the water it was. I watched it drop straight down towards the water without touching anything.

I did pull down on the left joystick at the end but it was because the  drone was already dropping out of control and from what I saw the drone  was already making contact with the water so I was thinking I could  somehow cut off power and minimize the damage.
What makes you say that the drone was out of control?
It had lost a little height from 3:34.3 but apart from 0.3 seconds when you gave it a touch of left stick, you left the left stick untouched for nearly 20 seconds until 3:51.5.
The drone responded appropriately when you briefly touched the left stick at 3:41.6 and was responding normally to your right stick input.
Why didn't you give it some left stick up to make it climb ???
Why did you hold the left stick down hard for 6 seconds, making the drone descend and triggered a forced landing which finished the job for you?

Labroides Posted at 5-24 19:44
I did pull down on the left joystick at the end but it was because the  drone was already dropping out of control and from what I saw the drone  was already making contact with the water so I was thinking I could  somehow cut off power and minimize the damage.
What makes you say that the drone was out of control?
It had lost a little height from 3:34.3 but apart from 0.3 seconds when you gave it a touch of left stick, you left the left stick untouched for nearly 20 seconds until 3:51.5.

I only have the times from the airdata app but I released the controller at 3:57.3, at 3:59.3 I started to turn to the left to bring it back but noticed turning to the left made it visually start to drop. The airdata app shows that when I started to turn at 3:57.3 the drone dropped 1.8ft. At this point it was just above the water and not at 5.9' as indicated in the app.
I remember realizing that it was going in the water and RTH wasn't kicking in so I pulled down on the left joystick to attempt to cut power so the water wouldn't totally burn it up. At the time it seemed to make sense.
Pulling down on the joystick at the end was a bad decision but my issues are with the several drops in altitude when it should have been hovering when I left go of the controls.
I'm sure a more experienced operator would have continued to pull up and I should have atleast tried it but it appeared that it was already too late with the way it was dropping.

I think Lab is right about it being a long way off. It may have looked like it was on the water surface when that was probably not the case. It was a risky move in our opinion for a rookie (like me). Don't give up. "Stuff" happened ;-)

GaryDoug Posted at 5-24 20:18
I think Lab is right about it being a long way off. It may have looked like it was on the water surface when that was probably not the case. It was a risky move in our opinion for a rookie (like me). Don't give up. "Stuff" happened ;-)

Yeah I definitely don't want to give up on droning. It was a blast for the short time I had it.

B Mills Posted at 5-24 19:58
I only have the times from the airdata app but I released the controller at 3:57.3, at 3:59.3 I started to turn to the left to bring it back but noticed turning to the left made it visually start to drop. The airdata app shows that when I started to turn at 3:57.3 the drone dropped 1.8ft. At this point it was just above the water and not at 5.9' as indicated in the app.
I remember realizing that it was going in the water and RTH wasn't kicking in so I pulled down on the left joystick to attempt to cut power so the water wouldn't totally burn it up. At the time it seemed to make sense.
Pulling down on the joystick at the end was a bad decision but my issues are with the several drops in altitude when it should have been hovering when I left go of the controls.

At this point it was just above the water and not at 5.9' as indicated in the app.
The app doesn't indicate that you were 5.9 ft above the water.
It indicates that you were 5.9 ft higher than the launch point.

I remember realizing that it was going in the water and RTH wasn't  kicking in
RTH didn't "kick in" because there was no action from you to initiate RTH.

so I pulled down on the left joystick to attempt to cut power  so the water wouldn't totally burn it up. At the time it seemed to make  sense.
It doesn't make any sense now.
It seems that making the drone climb away from the water would have made a lot more sense.

When you are a new flyer, it's a very good idea to stay well clear of obstacles and even more so when you are too far away to clearly  see the relative positions of the drone and obstacles.
When you are more experienced, you understand this and still stay away from obstacles because it only takes a small movement in the wrong direction for everything to end in tears.

Labroides Posted at 5-24 21:25
At this point it was just above the water and not at 5.9' as indicated in the app.
The app doesn't indicate that you were 5.9 ft above the water.
It indicates that you were 5.9 ft higher than the launch point.

Oh good to know about the hight from take off.
Thanks for the information.

Your Video

..... wow

JetSam Posted at 5-24 22:16
..... wow

I'm in the process of loading the full video. The one I originally loaded only showed the last few seconds.

B Mills Posted at 5-24 22:18
I'm in the process of loading the full video. The one I originally loaded only showed the last few seconds.

ah ok !! sorry for your lose

JetSam Posted at 5-24 22:24
ah ok !! sorry for your lose

Thanks man.

B Mills Posted at 5-24 17:39
Thank you Vlas, definitely sad and frustrating.

Hope you are in the air again soon with a replacement.

Before taking the air again I think you should familiarize a bit more with your Mavic Mini aircraft, possibly in the open with perfect satellite reception. It's sad to see a Mini sink like this.

1 Km! According to your latest stats... that Mavic Mini was 1 kilometer old. I won't criticize anything since I don't like shooting the Red Cross.

Next time find yourself a big empty parking space, something like that... or a field which is even better. I am wondering what prevented you from saving the Mini... that river seems entirely walkable.

m80116 Posted at 5-25 10:22
Before taking the air again I think you should familiarize a bit more with your Mavic Mini aircraft, possibly in the open with perfect satellite reception. It's sad to see a Mini sink like this.

1 Km! According to your latest stats... that Mavic Mini was 1 kilometer old. I won't criticize anything since I don't like shooting the Red Cross.

Yeah I shouldn't have been over that creek. I flew earlier in a field and everything went great I thought I had it down. And I have been wanting this creek shot for a few years. Not sure I will get another drone or not just yet.
Believe me I tried everything to find it unfortunately it was much deeper and Rapids where I was standing I ended up jumping in falling and getting carried by the Rapids further Downstream. By the time I walked the creek back up to where it went in I believe it probably passed me. I spent about five hours checking every spot in the creek then walked the shore about a mile south spoke to some fly fisherman who stated they did not see it.
Expensive lesson learned. If I do get a drone again I will not fly that close to water. I didn't expect it to drop like it did before I strangely pull down the joystick. I actually did a test run of this shot on land and the stability was incredible, never dropped once like it did over the water.

B Mills Posted at 5-25 10:40
Yeah I shouldn't have been over that creek. I flew earlier in a field and everything went great I thought I had it down. And I have been wanting this creek shot for a few years. Not sure I will get another drone or not just yet.
Believe me I tried everything to find it unfortunately it was much deeper and Rapids where I was standing I ended up jumping in falling and getting carried by the Rapids further Downstream. By the time I walked the creek back up to where it went in I believe it probably passed me. I spent about five hours checking every spot in the creek then walked the shore about a mile south spoke to some fly fisherman who stated they did not see it.
Expensive lesson learned. If I do get a drone again I will not fly that close to water. I didn't expect it to drop like it did before I strangely pull down the joystick. I actually did a test run of this shot on land and the stability was incredible, never dropped once like it did over the water.

Well I can share your grief but I think you have to accept the lesson as a whole.

It wasn't the MM dropping... it was all the many disregarded good practices (something that even experienced pilots should adhere to), like flying with a good sky view, not above and close to water, and even the home point is too close to the bridge for my liking.

But what ultimately doomed your Mavic Mini was the user input, I am afraid you have something to do with it. I wish I couldn't say that... I know honesty is one of my biggest downfall.

B Mills Posted at 5-24 21:27
Oh good to know about the hight from take off.
Thanks for the information.

He is partly right about the indication of altitude, but that is only for the Barometric/pressure reading. That always starts at zero at the start of flight. The parameter labeled "Sonar" on the Airdata site is actual altitude measured to the ground below. "Sonar" is a misnomer that must be a carryover from other drones. This one uses "visual" sensors that are useful up to about 10 meters. Beyond that it is not effective. That always starts near zero as well but obviously the actual elevation of the surface below the drone can change a lot during the flight.

GaryDoug Posted at 5-25 18:34
He is partly right about the indication of altitude, but that is only for the Barometric/pressure reading. That always starts at zero at the start of flight. The parameter labeled "Sonar" on the Airdata site is actual altitude measured to the ground below. "Sonar" is a misnomer that must be a carryover from other drones. This one uses "visual" sensors that are useful up to about 10 meters. Beyond that it is not effective. That always starts near zero as well but obviously the actual elevation of the surface below the drone can change a lot during the flight.

Oh great information. I learned a lot posting  here. I should have checked these forums before I started flying the thing. Thanks a lot for all the info.

Height -1.4m... you get too low and a down stick initiates landing. Seeing a few of these here lately over water.

I have to say I just had this same scenario. I am NOT a beginner pilot. I too was over a running stream when I could not stop a descent by the MM. I have 14 hr and 6 mins of flight time in every drone DJI has made. This was totally out of character. I was very close to my Mini. I watched it drift in hover as the water flowed below. Camera was off the water getting the kids in the river. Then I took the mini 50 feet from me up river to get a shot approaching the kids. As the mini was going up river, it began to lose altitude. No wind, no trees, clear moving water. I only had the forward stick on as I liked the 20 foot height for my fly by. The drone made a gradual and non-responsive drop in altitude directly into the water. The particular location was deeper than the rest of the river and being 50 feet away with the current I was not able to recover the drone. I will attempt to get my data, but this was not a beginner issue. I have flown over rivers and beaches my entire flying career.

skinnermk Posted at 5-26 20:16
I have to say I just had this same scenario. I am NOT a beginner pilot. I too was over a running stream when I could not stop a descent by the MM. I have 14 hr and 6 mins of flight time in every drone DJI has made. This was totally out of character. I was very close to my Mini. I watched it drift in hover as the water flowed below. Camera was off the water getting the kids in the river. Then I took the mini 50 feet from me up river to get a shot approaching the kids. As the mini was going up river, it began to lose altitude. No wind, no trees, clear moving water. I only had the forward stick on as I liked the 20 foot height for my fly by. The drone made a gradual and non-responsive drop in altitude directly into the water. The particular location was deeper than the rest of the river and being 50 feet away with the current I was not able to recover the drone. I will attempt to get my data, but this was not a beginner issue. I have flown over rivers and beaches my entire flying career.

Wow sorry to hear. It definitely dropped on me even though I then panicked and helped it the rest of the way. But the way it was dropping I felt like it woild have kept going without my input anyway but no way to know in my case. All I know is if I get another one I will not be getting near water ever again. Unfortunately a lot of what I wanted to do was going to be low over water.
In my case the data confirmed what I saw that as soon as I turned left, the drone dropped almost 2ft in 4 seconds.

Here is my flight record. from 9ft to -3.3ft obviously underwater. My stick was NEVER in the down position except when i touched it to add altitude. It only registered down for less than 0.1 seconds then full up. Already hitting the water. I have never had this issue with a DJI drone. I fly over water ALL the time. Rivers, ocean, anything. This was my first time with the Mini. I love to be a few feet off the water and do a fly by. Here it was 9+ feet, based on the replay and I never had a chance to bring this up. This needs to be fixed.
https://www.phantomhelp.com/logviewer/5F4W28CI0RYM0YW8MNL0

DJI please look at this and fix the mini software. Something is happening with moving water that makes it drop without responding to the controls.

I already ordered a second one. After reviewing the data, please help.

Even worse. It had a 128GB 10x SDcard in it. Thank god I downloaded everything I had on it before putting it in the MINI