Hi,
Many years, as a RC models tinker, I piloted others' drones for filming different things as I have pretty good skills with the remote sticks, they say. But only a few weeks ago I had the money to buy a Mavic 2 Zoom for me (second hand). It was in good condition judging by the fact it almost has no scratches, so I assumed it had never been crashed. Few days later I noticed some gimbal minor jitters on the yaw axis but this is another story.
Back to the crash day: I was hiking with my son and that flight was the 3rd in that day. All happened in seconds but this is what I remember:
- after powering up the drone asked for mag calibration. I did it.
- the take off was from my hand
- I also noticed DJI Go4 on the phone connected to RC1A controller was greyed out intermitently as if the USB type C connector would have not been properly inserted. This happend before take off and after. I tried to push it once again and the app seemed to recover eventually
- I started to manouver the drone for a lift and reveal" type of shot and while I was setting up some image parameters I remember I saw on the phine screen a message with "internal space is full, will you switch to SD card?" which I did not understand, indeed the internal was full but in that day I had shot on SD a few time before.
- when I tried to touch that message hoping it will change to SD card, I noticed the app screen was once again grayed and the drone was descending (on its own) pretty alarming behind the edge of the rock I was climbed on. I desperatly tried to use de sticks to avoid the danger... no sign of response from the drone. It was a few meters away, imagine the panic that I could not do anything but watching it smashing the props onto the rocks and the fight controller wasn't doing anything in my efforts to recover. I think I pushed the RTH button too, I say "I think" because there were some desperate seconds. I might as well had pushed the power on button.
- one of the props jump off the motor and the drone fell off about 10-15m, bouncind on the wall of the rock.
- with all its sensors, the drone couldn't avoid (is set to brake on obstacle) that wall of rock. In previous flight the collision avoidance was working because I can remember all those beeps and brakings when taking off or landing in my hand.
Back home I noticed the locking notches of the rear arms were destroyed (it can be fixed - I have electronics skills), the motors of the gimbals were not functioning but eventually I discovered an unplugged connector, I fixed that too. Camera is in good shape. Only that the gimbal has now even bigger jitter on the yaw axis.
Anyway, I downloaded the log file for that particular flight with DJI Assistant because on my phone (I guess because of those app disconnects) that particular log is very short and incomplete.
Here is the log file from the drone (>900MB) - I downloaded only the last log matching the crash timestamp It seems I can't post a link to some filesharing website. Where can I post such a big file so is accepted by DJI forums?
Later edit:Here is the log:
Thank you for the patience to read such a long post. Maybe someone can decrypt the logs and find out if there was an pilot errror of something else. Even if I will replace the affected parts (and I will do it) I am really afraid of flying until I won't know the problem.
The DAT log from the drone is of no use to anyone but DJI, they are encrypted.
What you need are the .txt and DAT from the phone or tablet that you were using,
Assuming you have a Windows computer, connect the phone/tablet to the computer via USB cable and look for the .txt in
Computer/phone's_name/Phone/DJI/dji.go.v4/FlightRecord
Look for the DAT in
Computer/phone's_name/Phone/DJI/dji.go.v4/FlightRecord/MCDatFlightRecords.
Download the csv from the Phantomhelp page to comptuer.
Download CsvView from https://datfile.net/CsvView/downloads.html
and that can process both the .DAT & .txt fron the phone/tablet and give you graphical results.
Unfortunately, as I described in the initial post, my phone was disconnecting from RC1A controller, few times before take off and once or twice during flight. So the .TXT log in my phone is not complete. I checked the other 2 flights in that day end they are OK. I am posting the 3rd one here.I have never owned a DJI flying thing, since the crash I have been cathing up a lot o info about how things go with DJI, I hope maybe on this forum there are people fromn DJI which could help me with some info about what was wrong whit that flight. I have no waranty, no nothing, it is a second hand product .
Watching again the video I realize the drone was trying to executing a landing that I did not ordered from sticks nor app. It might have to do with the phone disconnecting from the remote controller. Although, the remote does not need the phone for piloting the drone, as far as I know.
florinel Posted at 8-12 12:25
Unfortunately, as I described in the initial post, my phone was disconnecting from RC1A controller, few times before take off and once or twice during flight. So the .TXT log in my phone is not complete. I checked the other 2 flights in that day end they are OK. I am posting the 3rd one here.I have never owned a DJI flying thing, since the crash I have been cathing up a lot o info about how things go with DJI, I hope maybe on this forum there are people fromn DJI which could help me with some info about what was wrong whit that flight. I have no waranty, no nothing, it is a second hand product .
Watching again the video I realize the drone was trying to executing a landing that I did not ordered from sticks nor app. It might have to do with the phone disconnecting from the remote controller. Although, the remote does not need the phone for piloting the drone, as far as I know.
"Unfortunately, as I described in the initial post, my phone was disconnecting from RC1A controller, f......"
Ooops my brain freeze sorry about that.
Did you have obstacle avoidance switched on?
Ah I had forgotten the M2Z has a hair trigger for failsafe behaviour, 2sec, it could be that a full disconnection triggered a landing because of the distance.
Sean-bumble-bee Posted at 8-12 13:09
"Unfortunately, as I described in the initial post, my phone was disconnecting from RC1A controller, f......"
Ooops my brain freeze sorry about that.
The obstacle avoidance was on for sure because I remember beeping because after taking off the drone sensed me. But tou are right to ask, sometimes I disable obstacle avoidance because I want to shot near things. But this was in another day, in a different place.
In the meantime I remembered something about the camera pointing down:
though it looks like the landing feature that changes camera position to the front in order to protect the lens...as a matter of fact I remember that seconds before I lost control, I tilted down a little the camera from the rotary knob on the remote. But now I realised that somehow it was like the remote freezed with my last command and due to some intermittent freeze (grayed dji app) of the screen I eventually saw that my camera was pointed all the way down (but I used that button only for short time). To me it looks like a freeze of the remote controller judging by the camera position . I wonder if trouble can happens from a bad USB plug during flight
I can't remember if the gimbal tilt dial has a variable maximum speed setting and I don't remember how quickly the dial can tilt the gimbal but it is possible to set at least one of the "C" buttons to toggle the gimbal between 90 down and horizontal and you do mention "but I used that button only for short time".
Do you have one of the C buttons set to do this?
Hi, florinel. Thank you for reaching out. We're sorry to read about what happened. Since the drone crash, we recommend sending it in for proper diagnosis and repair. Should you want to have a data analysis, you may request it as well but please note that there might be a fee depending on the warranty of the device. Hopefully, other users can provide you information that you needed.
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