Mini 2 crashed but why??

[Glenh]

Hi All

I was attempting to do a roof inspection. A very constricted site with about 30 ft between two 8 storey buildings. I got up to about level 6 when the drone went crazy, crashed into a wall and fell to the ground. I couldn’t see what happened as it was directly above me , with the sun behind.

Could be either loss of GPS signal, RC disconnected, updraft/wind turbulence, Interference from cell towers on the roof.

I have tried to upload the file to AirData website but it only accepts 15 MB (the file is .5 GB).

Any ideas wold be appreciated.

I have attached the flight log file , if it makes any sense to you.

 

[GerdS]

Guess you tried uploading the viceo file which is nonsense. You will need to upload the log file which is much smaller.
Two preferred ways for uploading:
1. You can either allow AirData.com access to your DJI account. Then sync your flights to your DJI account via the Fly app and AirData.com will then automatically sync itself.
2. You dan install the AirData UAV app and sync from there.

 

[Glenh]

Thank you. I will try that

 

[Meta4]

Could be either loss of GPS signal, RC disconnected, updraft/wind turbulence, Interference from cell towers on the roof.

GPS would have been restricted, but losing GPS doesn't cause a drone to "go crazy".
Neither does losing signal or nearby mobile phone towers.

Data needed to tell anything about the incident.

Here are a couple of options ...

1. Go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record from your phone or tablet.
That will give you a detailed report on the flight data.
Come back and post a link to the report it provides and someone might be able to analyse it and give you an understanding of the cause of the incident.
or
2. Just post the .txt file here
or
3. If you use Airdata, you can view the flight data on Airdata and post a link for the Airdata report

The relevant file is a .txt file and it's a lot smaller than 0.5GB

 

[Felix le Chat]

Hi All

I was attempting to do a roof inspection. A very constricted site with about 30 ft between two 8 storey buildings. I got up to about level 6 when the drone went crazy, crashed into a wall and fell to the ground. I couldn’t see what happened as it was directly above me , with the sun behind.

Could be either loss of GPS signal, RC disconnected, updraft/wind turbulence, Interference from cell towers on the roof.

I have tried to upload the file to AirData website but it only accepts 15 MB (the file is .5 GB).

Any ideas wold be appreciated.

I have attached the flight log file , if it makes any sense to you.

You were in the worst possible area to begin with. 16 floors (8 each side) of WiFi noise from home routers and mobile devices blasting out. Lots of metal reinforcement (if they're modern structures) powerful signals from the cell repeaters and then you've got the potential for lots of lovely updraft, downdraft, shear, Eddys and the silent killer: your own propwash, which will happily drag your drone around and into the nearest wall. DJI has a dedicated flyaway team and they recommend not flying, or doing so with extreme caution, in areas of strong radio frequency interference.

 

[Starz]

powerful signals from the cell repeaters

I’ve seen this thought mentioned before but have not seen any proof that it’s an issue. Do you have any link to information regarding it being detrimental to flying cameras?

 

[Felix le Chat]

I’ve seen this thought mentioned before but have not seen any proof that it’s an issue. Do you have any link to information regarding it being detrimental to flying cameras?

Yeah. A saved conversation with one of the DJI flyaway team reps, who shunted the query up two levels, then came back with the " official RF interference" answer. On top of that: it's stated quite clearly in the user manual, but a lot of people insist it's an urban myth and everything is down to flier error, I have a tendency to listen to the people who designed the things.... They usually know best what makes 'em tick.

 

[Meta4]

Yeah. A saved conversation with one of the DJI flyaway team reps, who shunted the query up two levels, then came back with the " official RF interference" answer. On top of that: it's stated quite clearly in the user manual, but a lot of people insist it's an urban myth and everything is down to flier error,

It is an urban myth and your "flyaway team" person is probably just one of the almost useless DJI support people who know nothing that isn't written in the scripts they work from.
DJI documentation is full of misinformation and excessively cautious safety warnings.

I have a tendency to listen to the people who designed the things.... They usually know best what makes 'em tick.

You'll never hear anything from the people who actually design DJI drones.

 

[Felix le Chat]

It is an urban myth and your "flyaway team" person is probably just one of the almost useless DJI support people who know nothing that isn't written in the scripts they work from.
DJI documentation is full of misinformation and excessively cautious safety warnings.


You'll never hear anything from the people who actually design DJI drones.

Well, there's a simple solution isn't there. Why don't you contact the flyaway team yourself. You can find 'em easy enough if you trawl through the DJI sitemap. Then you can tell them they are a figment of the imagination and are as useful as a chocolate tea pot. I'm sure they'd appreciate your input.

 

[Meta4]

Well, there's a simple solution isn't there. Why don't you contact the flyaway team yourself. You can find 'em easy enough if you trawl through the DJI sitemap. Then you can tell them they are a figment of the imagination and are as useful as a chocolate tea pot. I'm sure they'd appreciate your input.

I wouldn't waste my time.
I've analysed the flight data from hundreds of flight incidents.
I give detailed analysis for the owners, something that DJI never does.
I hear forum people every week blaming interference for any incident they don't understand.
I've seem lots of flight probleams, but nothing at all to even hint that interference can cause a drone to fly erratically.

And I'm quite certain that the people you talked to don't fly drones or know anything about flying drones.
That's normal for anyone from DJI that you can contact.

 

[Felix le Chat]

Perhaps they'd appreciate some expert assistance then? I understand they pay quite well.

 

[Meta4]

Perhaps they'd appreciate some expert assistance then? I understand they pay quite well.

I provide help to users here, but I can see that you are more interested in myths than factual information.

 

[Felix le Chat]

not really. The bloke who took the time to settle the matter was named 'Chris' not 'Harvey'.

 

[Cafguy]

If you lose connection with your drone-- your drone Will stop and hover or try and return home. Now if it tried to come home you would have gotten a warning from the tiny lady in the controller.
It is rare for the drone to just do things on its own such as fly into a wall or just flyaway after it is disconnected. I have built and repaired many DJI Style drones {GPS Camera drones} but I have not seen one crash simply because it got disconnected- other factors were also involved.
My best guess without knowing anything about your drone would be some sort of interference but without that log I am just pulling ideas out of the air. You should follow the advice above to post the logs.
ALSO
Just like every company in the world DJI has a book of printed responses for their employees to give to customers. I think the biggest reason for this is they do not want to pay engineers to sit by the phone and solve customer complaints- a very wise move indeed.
DJI can help you in limited cases but if you are not sure of the problem DJI wont be much help. I have always gotten better advice from other users on forums such as these.

 

[Felix le Chat]

I provide help to users here, but I can see that you are more interested in myths than factual information.

Just to dot all the 'i's' and cross all the 't's'... I found the e-mail I got from 'Harvey'.

Message to DJI FLYAWAY TEAM. (NOT the DJI FORUM)

"...Mini 3 Pro - The black sticker inside the battery bay: Left sidewall.

This reads:
"This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions. 1. This device may not cause harmful interference and 2. This device must accept any interference received. Including interference that may cause undesired operation."

(2.) infers that the drone WILL be adversely affected by WiFi/Bluetooth/RF signal interference with the set control frequencies - because it was designed that way.

The interesting two words in the disclaimer are: "undesired operation". Which infers a drone that either will not respond to stick input, or will act in a contrary manner to stick input.

Is this another way of saying R/F interference may cause a 'fly-away'?..."


A request for clarification of the phrase "undesired operation" went up through two tiers of technical support.


Response from DJI FLYAWAY TEAM. (NOT the DJI FORUM)


"...Sorry for the delay - I'd like you to know that I've already reached out to our next level team and they have noted that "may cause undesired operation" simply means, in the context of our conversation earlier, (concerning areas of high level R/F interference) causing the drone to not respond to stick input: or act in a contrary manner to stick input.

The advice is to be cautious about flying the aircraft in areas where environmental hazards could potentially cause high signal interference like in the vicinity of electricity sub-stations/high voltage lines/RF transmitters and areas of Wi-Fi saturation.

This has been added to the appropriate user documentation.

I hope this addresses your concerns. In case you have additional questions please know that I'm just an email away.

Cheers

Chris..."


He assures me he is not a white, six foot tall invisible rabbit and I'll take him at his word.

 

[Felix le Chat]

From the user manual.

 

[Starz]

In reading the two above posts that you’ve provided, and thank you for your time involved in that, and from several years of reading crash and wayward drone analysis form several of this forum’s members, I’m still not seeing substantial proof that a cell facility provides unwanted flight characteristics. I may have missed something so I’ll keep looking.

 

[Meta4]

From the user manual.View attachment 169224

This exactly what I described in my previous posts and completely unconvincing.
All of that is the same overly cautious stuff about what MIGHT happen (but never does) that DJI pushes, without any evidence that it is true.
It seems more likely to have been written by lawyers than drone experts.
If I believed other similar things that have been in DJI manuals in the past, I'd never fly over water because it MIGHT cause unexplained problems.
Or I would have recalibrated by compass before each flight or any time I moved away from a previous flying site.

If it makes you comfortable, go ahead and swallow it.
I fly according to evidence based principles, not fairy tales.
This is my 10th year of flying DJI drones.
I've flown almost 10000 kilometres , mostly over water and often in winds significantly stronger than DJI call severe weather conditions.
I've flown from moving boats and never recalibrated a compass since 2015 despite flying at sites several thousand kilometres apart.

I've have a science degree and an inquiring mind and have learned a lot about drone flying from my own experience and from analysis of hundreds of incidents from other flyers, but very little from DJI documentation.

 

[Meta4]

(2.) infers that the drone WILL be adversely affected by WiFi/Bluetooth/RF signal interference with the set control frequencies - because it was designed that way.

The interesting two words in the disclaimer are: "undesired operation". Which infers a drone that either will not respond to stick input, or will act in a contrary manner to stick input.

Is this another way of saying R/F interference may cause a 'fly-away'?..."

It shouldn't be taken to mean that at all.
As anyone who has flown with interference knows, it might cause minor interruptions in signal, but it won't and cannot cause something that you might call a "flyaway".
At worst, it might swamp your control signal, which would trigger whatever failsafe action is set in the app.
This is almost always RTH and that would bring the drone home.

The widespread myth of interference causing erratic flyaways is just nonsense and has never been observed.

 

[mobilehomer]

It shouldn't be taken to mean that at all.
As anyone who has flown with interference knows, it might cause minor interruptions in signal, but it won't and cannot cause something that you might call a "flyaway".
At worst, it might swamp your control signal, which would trigger whatever failsafe action is set in the app.
This is almost always RTH and that would bring the drone home.

The widespread myth of interference causing erratic flyaways is just nonsense and has never been observed.

No, Felix, Meta is correct, it doesn't mean that at all!!! What is DOES mean is that the device(and this warning is on ALL your electronic devices) will not be damaged by extraneous radio signals. I have flown within yards of cell towers without so much as a minor glitch in video or control!!