Lost connection and crashed

[runeOfRune]

@Waliaf could you tell us more about the aircraft?

1. Was it a new unit, refurbished or replacement?
2. Please describe how your typical IMU calibration looked like.
3. Were the batteries brand new?
4. Did you turn off the aircraft while the battery was updating?
5. Do you recall an event where it refused to turn off?
6. Do you remember any previous notable issues with the craft?
7. Did you attach anything to the drone?

 

[Waliaf]

@runofrun

1. Was it a new unit, refurbished or replacement?

(It was a new drone, got it few weeks ago, my first flight data is included on the zip file that I have shared)

2. Please describe how your typical IMU calibration looked like.

(IMU calibration was fine I did it earlier in the morning)


3. Were the batteries brand new?

(The batteries were new, then one which I got with drone -fly more combo)


4. Did you turn off the aircraft while the battery was updating?

(No I did not, earlier in the day when I connected to AC it mentioned that I have to update - I think it was for the the RC and AC update (?)- then after the update I had to restart the AC manually, instructions that I got on RC. Later in the day I did change the batteries bit there came no updates pop-up when I did connect to AC)

5. Do you recall an event where it refused to turn off?

(Nope did always turn off)

6. Do you remember any previous notable issues with the craft?

(Not particularly, sometimes it was saying that not able to take off and need to calibrate)


7. Did you attach anything to the drone?

In Germany you need to attach your address , phone to drone , ingot my labor from this shop Drone Tag Labels and Plaques [ Shop ]

Question:
It looks.likenthay I have lost the last flight data , maybe due to memory issue with my phone , was running out of space (?) I there a way to get the logs from the AC which might be useful?

I saw a lot of replies and speculation, I am totally new into this so have to idea how to read these data and what I should conclude. At this stage I am not sure if I should go for DJI support or should use my DJI Care?

Anyhow, this is a discovery for me and I am learning from it.

Thank your for your time and support!!!

 

[Waliaf]

When I open this and look at the map this was one of my last flights not the one that AC crashed ... Batteries warring can be correct as I was funny out of it, the I returned the AC home and change the batteries

I didn't try running it through the Phantomhelp site - that may be unable to read it with the extra data on the end. Try this:

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

 

[Waliaf]

Yikes!!!

This is the crash moment, I see reds on the cell deviations, what does this mean could this cause the crash?

 

[paulatkin73]

I'm not sure what you mean by garbage - it does have an extra line of data on the end that is spurious, but the rest of the file is fine.

View attachment 75192

DJi lacks proper telemetry to troubleshoot stuff like that.
at the mark 262.2 IMU1 died. all its signals cut off at that time. why this BS did not switch to IMU0 - who knows. would be really nice to be able to see internal cpu stats here and board temperature. esc temp readings are all fine, so, it is not it. yet it seems those IMUs in mavic 2 keep failing. pity and a total shame.
if you have other crash .dat files - did you see, statistically, which IMU usually dies more often - 1 or 0?

 

[Meta4]

is the crash moment, I see reds on the cell deviations, what does this mean could this cause the crash?

No .. a 0.1V difference in cell voltages is nothing.
It certainly wouldn't cause a crash.

 

[sar104]

When I open this and look at the map this was one of my last flights not the one that AC crashed ... Batteries warring can be correct as I was funny out of it, the I returned the AC home and change the batteries

This is the crash moment, I see reds on the cell deviations, what does this mean could this cause the crash?View attachment 75239

Your posts are very confusing. First you say that's not the correct flight, then you post a snapshot from that exact log and say that it is the crash.

 

[sar104]

DJi lacks proper telemetry to troubleshoot stuff like that.
at the mark 262.2 IMU1 died. all its signals cut off at that time. why this BS did not switch to IMU0 - who knows. would be really nice to be able to see internal cpu stats here and board temperature. esc temp readings are all fine, so, it is not it. yet it seems those IMUs in mavic 2 keep failing. pity and a total shame.
if you have other crash .dat files - did you see, statistically, which IMU usually dies more often - 1 or 0?

View attachment 75254

IMU_1 did fail, but it wasn't the active IMU. You need to look at the txt log, which shows the active IMU, before assuming which one was in use from the DAT file.

 

[Waliaf]

Anyhow I opened the case with DJI to see what they can find , I don't want to use mm DJI Care at first place

 

[Waliaf]

Your posts are very confusing. First you say that's not the correct flight, then you post a snapshot from that exact log and say that it is the crash.

View attachment 75270

You are right , I was confused, I could not see the dates, I looked at the map and I recognized the location of crash, that's two different posts.

 

[Waliaf]

Thanks for your reply, I am new and have not strong technical background. What does IMU doing and what could cause the power cutoff? What is the best way to do troubleshoot this?

DJi lacks proper telemetry to troubleshoot stuff like that.
at the mark 262.2 IMU1 died. all its signals cut off at that time. why this BS did not switch to IMU0 - who knows. would be really nice to be able to see internal cpu stats here and board temperature. esc temp readings are all fine, so, it is not it. yet it seems those IMUs in mavic 2 keep failing. pity and a total shame.
if you have other crash .dat files - did you see, statistically, which IMU usually dies more often - 1 or 0?

View attachment 75254

 

[Waliaf]

Thanks, I opened the case to DJI. I bought the drone in Netherlands but I am located in Germany, while opening the case DJI support portal gives me error that I cannot make use of DJI Care ( which I was not planning to use anyways at this moment) . I am really interested to know what happened , was it my fault? Then I can be more careful next time , was it AC (Hardware or Software) fault? How can DJI prevent it... ? It is very scarry if you fly and drone crash for whatever reason... It can cause serious damage and injuries , if it falls on someone

 

[Gryphon962]

I downloaded the kml file from the phantomlogviewer page and opened it in google earth, so we can see the flight profile in 3d. The image is below. From this, and the log, it seems the drone sat in the hover about 100' away from the home point at over 500' for about 20 seconds before it failed. (Final red dot of three). The OP reports it fell into the street 60m away from him - which is consistent.

1) Recommend the OP sends the drone back to DJI for replacement, and makes sure they understand this fell out of the sky from 500' over an urban area while in line of sight of the controller, only 100' away horizontally. DJI needs to figure out what happened to stop this sort of thing happening again.

2) Recommend that we, as mavic forum members, do more to encourage users to fly safe profiles. This flight profile was never a good idea. If you really have to fly over a city at 500' please keep your flight path over a river, trees, or other area where the risk of damage or injury is minimized.

3) The other thing we can do as mavic forum members is to compile a list of logfile events that are warnings of **** about to happen, so that users can search their logs for keywords like 'core recovery' and 'AP reboot' to try and catch problems before the terminal flight.

 

[runeOfRune]

A‍s i‍'ve‍ a‍lre‍a‍dy‍ e‍xpla‍i‍ne‍d, thi‍s dro‍ne‍ ha‍d i‍t co‍mi‍ng fro‍m the‍ ve‍ry‍ fi‍rst re‍co‍rde‍d fli‍ght (FLy‍002) whe‍re‍ i‍t re‍po‍rts ba‍tte‍ry‍ co‍mmu‍ni‍ca‍ti‍o‍n i‍ssu‍e‍s fo‍r the‍ fi‍rst ti‍me‍. Whi‍ch ma‍de‍ me‍ a‍sk i‍f the‍ u‍ni‍t wa‍s a‍ re‍fu‍rb. The‍n i‍t o‍nly‍ go‍t wo‍rse‍.

3) The‍ o‍the‍r thi‍ng we‍ ca‍n do‍ a‍s ma‍v‍i‍c fo‍ru‍m me‍mbe‍rs i‍s to‍ co‍mpi‍le‍ a‍ li‍st o‍f lo‍gf‍i‍le‍ e‍ve‍nts tha‍t a‍re‍ wa‍rni‍ngs o‍f **‍** a‍bo‍u‍t to‍ ha‍ppe‍n, so‍ tha‍t u‍se‍rs ca‍n s‍e‍a‍rch the‍i‍r lo‍gs fo‍r ke‍y‍w‍o‍rds li‍ke‍ 'co‍‍re‍ re‍co‍v‍e‍ry‍' a‍nd 'A‍P re‍b‍o‍o‍t' to‍ try‍ a‍nd ca‍tch pro‍b‍le‍ms be‍fo‍re‍ the‍ te‍r‍mi‍na‍l fli‍‍ght.

I‍ wa‍‍s bri‍‍e‍fly‍ thi‍n‍ki‍ng a‍bo‍‍u‍t ma‍‍ki‍ng a‍ lo‍‍g i‍nte‍rp‍re‍te‍r s‍i‍te‍, bu‍t i‍'d h‍a‍ve‍ to‍ th‍e‍n fi‍gu‍re‍ o‍u‍t ho‍w to‍ sa‍fe‍ly‍ ru‍n da‍‍tco‍‍n o‍n a‍ V‍P‍S e‍tc... I‍'m to‍‍o‍ la‍zy‍ to‍ fi‍dd‍le‍ wi‍th the‍ wh‍o‍le‍ se‍‍tu‍p. ?

 

[Macabre]

Your usable flight data ends abruptly 304 seconds into flight 89. Prior to the crash, even during your previous successful flight, your aircraft experienced multiple IMU convergence errors, multiple instances of horizontal and vertical drift, multiple disconnects, multiple vision system errors, multiple ultrasonic system errors, eram write errors (???), battery API errors, accelerometer errors... Unless I'm reading the logs wrong, I have never seen anything like this.

As to the actual reason of the crash, I cannot help you as the logs did not record the final event. But I guess some of those listed had at least a partial impact.

Where did you get that aircraft from...? What did you do to it?

Aliens.

 

[Gryphon962]

I‍ wa‍‍s bri‍‍e‍fly‍ thi‍n‍ki‍ng a‍bo‍‍u‍t ma‍‍ki‍ng a‍ lo‍‍g i‍nte‍rp‍re‍te‍r s‍i‍te‍, bu‍t i‍'d h‍a‍ve‍ to‍ th‍e‍n fi‍gu‍re‍ o‍u‍t ho‍w to‍ sa‍fe‍ly‍ ru‍n da‍‍tco‍‍n o‍n a‍ V‍P‍S e‍tc... I‍'m to‍‍o‍ la‍zy‍ to‍ fi‍dd‍le‍ wi‍th the‍ wh‍o‍le‍ se‍‍tu‍p. ?

Too much work. All I had in mind was a sticky post with a list of 'events' that, in the experience of those who review logs of malfunctioning drones, are bad news, and should be investigated by the user before next flight - ideally in their own backyard. The drone in this post had multiple 'AP reboot' events before it fell out the sky. I've been on this forum a few weeks and know about that one, and 'core recovery' but I expect there are others that we could look for if we knew what they were. Prevention is better than investigation

 

[ProDaddy]

Hi all

I was flying in a all city in Denmark, the connection was perfect, distance was in cos and I was not flying very high. At certain moment I got the error connection lost, and I saw then the M2P just going down it was crazy, the aircraft crashed 60 meters from me, lucky there was no one on street. The front sensors are damaged, I cannot fly.

I have fresh care but the aircraft is also not very old. What should I do?

Contact DJI Customer Support, I crashed my MPP with only 1;46 Flight Time, No Fresh Care Ins. Basically it was totaled, (Hit High Voltage Power Line, Crashed into traffic, Camera Board, Flight Board both trashed), 2 most expensive parts to replace, DJI fixed totally, (required me to get Ins.), Be Honest, Polite, they will help you.
Good Luck;
Pro-Daddy
USA

 

[Waliaf]

Thanks! I will be in touch with DJI I am not sure if they will accept or blame me for this crash, but as far as I can read so far it was rather the AC error. How does it work, is there a kind of "black box" in QC that it records the flights as well?

I downloaded the kml file from the phantomlogviewer page and opened it in google earth, so we can see the flight profile in 3d. The image is below. From this, and the log, it seems the drone sat in the hover about 100' away from the home point at over 500' for about 20 seconds before it failed. (Final red dot of three). The OP reports it fell into the street 60m away from him - which is consistent.

1) Recommend the OP sends the drone back to DJI for replacement, and makes sure they understand this fell out of the sky from 500' over an urban area while in line of sight of the controller, only 100' away horizontally. DJI needs to figure out what happened to stop this sort of thing happening again.

2) Recommend that we, as mavic forum members, do more to encourage users to fly safe profiles. This flight profile was never a good idea. If you really have to fly over a city at 500' please keep your flight path over a river, trees, or other area where the risk of damage or injury is minimized.

3) The other thing we can do as mavic forum members is to compile a list of logfile events that are warnings of **** about to happen, so that users can search their logs for keywords like 'core recovery' and 'AP reboot' to try and catch problems before the terminal flight.

View attachment 75555

 

[Waliaf]

Thanks! I will update this post, I hope I get it back in 4 weeks then I can take it with me to holidays

Contact DJI Customer Support, I crashed my MPP with only 1;46 Flight Time, No Fresh Care Ins. Basically it was totaled, (Hit High Voltage Power Line, Crashed into traffic, Camera Board, Flight Board both trashed), 2 most expensive parts to replace, DJI fixed totally, (required me to get Ins.), Be Honest, Polite, they will help you.
Good Luck;
Pro-Daddy
USA

 

[BudWalker]

..............

3) The other thing we can do as mavic forum members is to compile a list of logfile events that are warnings of **** about to happen, so that users can search their logs for keywords like 'core recovery' and 'AP reboot' to try and catch problems before the terminal flight.

I had thought of adding something like that to DatCon. Pretty easy to do. The hard part is knowing which entries are significant. The contents of the eventLog stream are different for each platform and each firmware version. I get the impression that some of the entries are just debug statements that are otherwise insignificant. They may sound ominous but just indicate a certain condition being encountered.