Hi friends,

I just crashed my drone during take-off and need help analyzing flight log to find out what exactly went wrong?

Im from Bangkok, Thailand using DJI mini 3 pro as my first drone. Been owning it and flying it everyday for the past 1 month.
With 110 flights, 248KM flown total flight time ~31 hours (latest from the RC control). Yes, i was flying about 3-4 flights per day since i got the drone.

I was taking my drone out for it's flight today at roughly 7:30PM here just outside my house as usual.
The ambient light and the sky was already dark which is not new, i have flown this drone at night frequently before. Love the green light from the drone that glows in the dark.

I turn-on my RC controller, then turn-on the drone. Check my RC controller and made sure the satellite signal is in white color with 20-22 connected sattlelights and home point is already updated before i press the take-off button on the RC screen. Once took off, the drone was not hovering perfectly still which is anticipated due to night time, so i made minor joystick controller adjustment so that it's hovering with in sight. (I usually let it hover just slightly higher than me for a minute or so before ascending and out I go) It was all normal at this point, unti like a minute later that i am ready to ascend further to really go out and start the tour. Suddenly while I am trying to ascend the drone went out of controll instead of just going directly upwards it went up and forward (without me pressing forward on the right hand, it went also full throttle on forward movement?) and finally hitting the power cable and falls to the ground.

I didnt calibrate anything since there was no notifications asking for one and i been flying in this same location.

I am suspecting that there must be a technical glitch somewhere, was hoping someone can help me read the flight log and explains to me what happen?
My flight log: https://drive.google.com/file/d/1TgBHngqttJBY9ZrCqi6pBZ3K_XtaXAxG/view?usp=sharing
My RC screen record: https://youtu.be/sPvT1mENQsY


Cheers,
Tee

coincidently, we had a change in the wifi-router at home today. the old one was too old and we replaced it. not sure if this can be related at all

Hi Tee-BKK
Sorry for your lose. Your screen record shows Blocked Motor, most likely cause of crash.
You uploaded the. Dat file.  Better to upload the .TXT file.

Use this link > https://www.phantomhelp.com/LogViewer/Upload/
It will tell you where to find .TXT log.
Then post the share link  here.

Pleomax Posted at 10-18 05:51
Hi Tee-BKK
Sorry for your lose. Your screen record shows Blocked Motor, most likely cause of crash.
You uploaded the. Dat file.  Better to upload the .TXT file.

Thank you for showing me this.


Please see the shared link:
https://www.phantomhelp.com/LogViewer/37FX7K2752OB6ANYRZBP

https://www.phantomhelp.com/LogViewer/37FX7K2752OB6ANYRZBP

It would seem that the "Motor unable to rotate" happens after i have already crashed?

Up until the 0m 31s i was ascending alright to 13 ft. Then the altitude drops to  negative -17 ft. indicating that i am already on the ground at that point "motor unable to rotate" happens.

I remember i have crashed already, but the drone did not instantly turn off, it kind of danced on cement ground a bit longer and sounded like a gimble broke off before it shut itself down

T T sad

Tee-BKK Posted at 10-18 06:42
It would seem that the "Motor unable to rotate" happens after i have already crashed?

Up until the 0m 31s i was ascending alright to 13 ft. Then the altitude drops to  negative -17 ft. indicating that i am already on the ground at that point "motor unable to rotate" happens.

Hi
Had a look at your log.

Agreed, on ground when motor blocked warning.
Couple of questions.
Was AC pointing East at take off?
Did you power up close to any metal objects?

At 23.8 yaw reading jumps from 56.4 to 320.3 degrees usually a sign of yaw error brought on by magnetic influence.

Questions, when the drone launched was it pointing more or less due east, along or parallel to the street?   Ahhh,  Pleomax is thinking along the same lines.
Do you think the flight track shown on the Phantomhelp (PH) page is accurate with regards to position? Both the PH track and your phone's track appear curved but where they 'take' teh drone seems to differ though that might be because one view looks straightdown whilst the background in  the other is seen from the side.
Just curious, did the drone take off from the roof of your building?

Pleomax Posted at 10-18 06:59
Hi
Had a look at your log.

If the picture/map orientation is north up in the link

The drone was pointing East when i turned it on, and i do intend to go in that direction.

When i power up, there was a 1 car near by say 2-3 meters away and 2 more cars maybe 5-6 meters away.

In my picture, the yellow star is the drone take off point. The arrows are where the drone was facing at take-off and direction i intend to go. The circle is the near by car (toyota altis not a big car)

but then i have seen people place drone on the car-roof and take off so i dont know if its something?

picture:  https://drive.google.com/file/d/1nIcrDO685rfZjVKg66BdRz-DmekYc4nW/view?usp=sharing

Sean-bumble-bee Posted at 10-18 07:01
Questions, when the drone launched was it pointing more or less due east, along or parallel to the street?   Ahhh,  Pleomax is thinking along the same lines.
How long after starting the motors do you think it hit the power cable?
Do you think the flight track shown on the Phantomhelp (PH) page is accurate with regards to position? Both the PH track and your phone's track appear curved but where they 'take' teh drone seems to differ though that might be because one view looks straightdown whilst the background in  the other is seen from the side.

Yes, i intend to go in this direction so i point it facing the direction when power up.

https://drive.google.com/file/d/1nIcrDO685rfZjVKg66BdRz-DmekYc4nW/view?usp=sharing

Sean-bumble-bee Posted at 10-18 07:01
Questions, when the drone launched was it pointing more or less due east, along or parallel to the street?   Ahhh,  Pleomax is thinking along the same lines.
How long after starting the motors do you think it hit the power cable?
Do you think the flight track shown on the Phantomhelp (PH) page is accurate with regards to position? Both the PH track and your phone's track appear curved but where they 'take' teh drone seems to differ though that might be because one view looks straightdown whilst the background in  the other is seen from the side.

I am sorry, please allow me to rephrase my reply to give most information from what i remember,

New image explaining locations: https://drive.google.com/file/d/1TKBOHzhJalGzk8b8JNhBf2SVYM9XevTa/view?usp=sharing

1. If the PH flight track map is north-up, my drone was launched due East along and parallel to the street as i intend to fly in that direction (Please see yellow star, that is the point of launch and yellow arrow is direction the drone is facing and where i intend to go)

2. Where did it hit the power cable ? I draw the power cable in blue line. Somehow the drone turns 180 degree and accelerated towards it. The blue star is where the dead drone was found just below the power cable.

3. Did i take off from a roof? Not this time, this time i took off from cement ground using a landing pad.
Other days i take off from the roof (some other times inside my home, where i open the front window, off the sensor and fly out, then turn on collision sensor back again during flight) but today i took off from a solid cement ground with a car parked near by (2-3 meters marked as yellow circle)

4. Is the PH flight track accurate? I think it's off by a little bit. As it indicated that i took off from a different house. My house is at the yellow star (not the red arrow). And the last known location drone was found is blue star (not the curved red dot)

Tee-BKK Posted at 10-18 07:54
I am sorry, please allow me to rephrase my reply to give most information from what i remember,

New image explaining locations: https://drive.google.com/file/d/1TKBOHzhJalGzk8b8JNhBf2SVYM9XevTa/view?usp=sharing

I think i hit the power line at 29-30 second, a 14ft to 16ft altitude seems to be accurate with where the powerline is

Good answers.  
I assume you clipped the cable somewhere around 31sec, would that be correct?
I have gone as far as I can so will have to wait and see what others think.
How bad is the damage to the drone?
You mention a broken gimbal in post 7 but I am not sure if that was a result of this crash or a previous crash.

Sean-bumble-bee Posted at 10-18 08:09
Good answers.  
I assume you clipped the cable somewhere around 31sec, would that be correct?
I have gone as far as I can so will have to wait and see what others think.

This is what is left of my drone. it is not in operational stage because the gimbal is broken clean off

Sadly this is the only crash i ever have so far. 1 crash and send my drone out of commission.

Hopefully it is not beyond repair but in Thailand there is no DJI care so i gotta pay up.

https://drive.google.com/drive/folders/1d8-VaDLRlu35wRI6Bu5Xv7-uca_7ffRS?usp=sharing

Perhaps the mods can provide a list of approved repair places or give you the address of  their official repairer etc.

If the likes of JJB and Labroides do not soon weigh in on this you could post a similar thread on https://mavicpilots.com/forums/-/list

Hello there Tee-BKK. I am sorry to read and to know what happened to your DJI Mini 3 Pro and thank you for reaching out. Since this unfortunate incident happened on your DJI Mini 3 Pro. I would recommend for you to contact our DJI Support Team at https://www.dji.com/support?site=brandsite&from=nav for further assistance. We have a team that will do there best to help you and give out the best resolution for the said issue. Again, I am sorry and thank you.

Tee-BKK Posted at 10-18 08:48
This is what is left of my drone. it is not in operational stage because the gimbal is broken clean off

Sadly this is the only crash i ever have so far. 1 crash and send my drone out of commission.

Did you take off from a balcony or the roof?  I ask as i see negative height

It looks to me like you may have clipped those cables, it was doomed from that point

Tee-BKK Posted at 10-18 06:42
It would seem that the "Motor unable to rotate" happens after i have already crashed?

Up until the 0m 31s i was ascending alright to 13 ft. Then the altitude drops to  negative -17 ft. indicating that i am already on the ground at that point "motor unable to rotate" happens.

At 23.6 seconds your drone started showing the signs of a yaw error.
This is caused by powering up in an area of magnetic interference which deflects the compass.
The IMU takes its initial direction values from the compass.
When the drone moves away from the magnetic influence, the compass returns to normal and you have conflicting compass and gyro data.
This results in the drone acellerating on a curved path without any joystick input.

The data indicates the drone was facing east at launch, but this is probably wrong.
What direction was the drone facing?

What surface did you launch from?
Was it reinforced concrete?