Mavic Mini sudden mode switch to confirm landing

[Deleted member 114080]

Yesterday I was making some arial pictures and movies at a client premesis. No special flight, just going up en look around. There was a little wind, I got two wind warnings, I didn't ignore them and descended a couple of meters and the warnings where gone. So I was finished looking around I was preparing to land. At 152.9 feet, 43 meters the mini switched suddely to Confirm Landing. I stopped Confirm Landing on the screen but I couldn't move the drone up or down. Just after cancelling Confirm Landing the Mini went again into Confirm Landing. It did it six time and each time I had to manual disengage the Confirm Landing. The question is why it did suddenly and repetitively switch to Confirm Landing ? Where exactly can I find the cause of that weird behaviour. I admit it felt pretty scary because I could not control the drone and I didn't understand why I got the Confirm Landing message which I had to cancell each time. Any tips ?

 

[sar104]

You will need to post the txt flight log to get an answer to that question - the Airdata screen shot doesn't include the necessary data.

 

[sirbadger]

Was it foggy?

 

[sar104]

Was it foggy?

An excellent question.

 

[Deleted member 114080]

No visibility was exellent, no fogg at all.

 

[Deleted member 114080]

You will need to post the txt flight log to get an answer to that question - the Airdata screen shot doesn't include the necessary data.

Okay, but still, where can I find the data you need to understand what happened. I would like totake a look myself.

 

[sar104]

Okay, but still, where can I find the data you need to understand what happened. I would like totake a look myself.

It's under all my posts:

Flight log retrieval and analysis guide

 

[Deleted member 114080]

Mavic Air Fly Away with Log it shows graphs, how do I get those graphs ?

 

[sar104]

Mavic Air Fly Away with Log it shows graphs, how do I get those graphs ?

You don't get those graphs unless you have Wavemetrics Igor Pro or a similar data analysis package and know how to program the analysis routines. The guide that I linked to does include other options for visualizing the data, however.

 

[Deleted member 114080]

I attached de log file, I wonder what you can find why this happened.

 

[sar104]

I attached de log file, I wonder what you can find why this happened.

Yes - the direct cause is clear - even though the IMU height was over 10 meters, the VPS system was reporting that the aircraft was within a meter or so of the ground towards the end of the flight. When full down throttle is applied with the VPS height less than a couple of meters the FC takes that as a command to land. The most common cause is fog or mist - hence the question above? If the conditions were clear, was there anything under the flight path that might have cause that? If not then the downward sensors are not reporting properly.

 

[Deleted member 114080]

Thanks a lot, yes It was a clear day. The only thing that's odd, there is an electricity plant next door. Could that caused interference ? Here's a pic looking down, you can see there is no fogg. I was flying around 43 meters high when confirm landing kicked in. So no way close to the ground or anything else. Still don't know why and what exactly happened

 

[sirbadger]

I'd get a support ticket raised with DJI

 

[sar104]

Thanks a lot, yes It was a clear day. The only thing that's odd, there is an electricity plant next door. Could that caused interference ? Here's a pic looking down, you can see there is no fogg. I was flying around 43 meters high when confirm landing kicked in. So no way close to the ground or anything else. Still don't know why and what exactly happened

View attachment 92828

Then I would do a sensor calibration and try a few flights in a safe location to see if the VPS altitude data are correct.

 

[Deleted member 114080]

I'd get a support ticket raised with DJI

I have find out how to get that ticket, I really wonder what happened. I did get a sensor error and I calibrated compass as the RC reuested me to do so. I can't find anywhere which sensor made an error. After calibrating the compass all seemed okay.

 

[Deleted member 114080]

Then I would do a sensor calibration and try a few flights in a safe location to see if the VPS altitude data are correct.

I will do. Could you tell me how to get those graphs, is it in the Pro versio of airdata ?

 

[sirbadger]

I have find out how to get that ticket, I really wonder what happened. I did get a sensor error and I calibrated compass as the RC reuested me to do so. I can't find anywhere which sensor made an error. After calibrating the compass all seemed okay.

Support Product - DJI

As the market leader in easy-to-fly drones and aerial photography systems, DJI quadcopters like the Phantom are the standard in consumer drone technology.

www.dji.com

Scroll down to other support options, where you can then choose your preferred contact method.

 

[sar104]

I will do. Could you tell me how to get those graphs, is it in the Pro versio of airdata ?

No - it's explained in the log analysis guide that I referred you to. I'm taking the raw log data and processing them in a scientific data analysis program (Wavemetrics Igor Pro). You can get somewhat similar functionality using CsvView, but there are no websites that do anything like this.

 

[Deleted member 114080]

(DJI) Your request (2581XXX) has been received and we will contact you as soon as possible. - I made a ticket, let's see what they come up with. I tried to get more specific info and experimented with some online programs. With phantonhelp I could come up with info below. Shows the hickup in the beginning of the flight.

 

[Deleted member 114080]

And here, at 9 m46.8 s at 152.9 ft it suddenly, without any input it decides to land, Why ?

9m 46.8s

Forced Landing

19satellites

152.9ft

0mph

21.5ft

56%

7.236V

3.618V

3.618V

0V