Sudden strong wind, Mini flew away

[kokesh]

To begin my post, I am an idiot. Flew high in clouds and didn't look that the drone flew far away. At approx. 70pct of battery I lost signal. When I got to the last point, approx 1km away, there was no connection to the drone either. I guess it got blown even further, with Return to home fighting the wind.

Anyone has any idea where to look? Here is my flight recording. I've looked in the straight line, if I'm right it would auto land on empty battery on the frozen lake. I went there, in a continuation line of the flight path, but haven't seen anything. I guess the engines would slow down the speed, continue flying in the same attitude and when the battery gets under 30pct land? Am I right?

Here is the flightlog:

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[Wilbur]

Taking a Mini to 1500'. You have more ***** than me.

 

[kokesh]

I know, must have had shortcut in my brain.

 

[sar104]

This one looks like a fairly straightforward case, and it should be possible to estimate where it ended up to within a reasonably small area. I'll do the calculations later today.

 

[Prismatic]

I know, must have had shortcut in my brain.

Short circuit, I'd say! ?

 

[kokesh]

This one looks like a fairly straightforward case, and it should be possible to estimate where it ended up to within a reasonably small area. I'll do the calculations later today.

Thank you!

 

[sar104]

Bad news I'm afraid. The wind at 460 meters height was 40 mph (18 m/s) out of the south, and at the end of the recorded flight the aircraft was moving due north at 6 m/s.



Looking at the battery depletion rate in RTH, and extrapolating to the smart battery autoland level at that height (22%) shows that it will have continued for another 420 seconds before commencing autoland. Extrapolating position based on the drift rate, followed by a 3 m/s descent rate, shows the following:



Plotting that on Google Earth, there's little doubt that it landed right in the middle of Ströms vattudal.

 

[kokesh]

Hi Sar104, thank you! It is not so bad news, the lake is frozen. There is a problem though, we had a snowstorm in the night. I'll check the ice and try to get there on snowshoes.

 

[slup]

Once in a while I think about what had happened if I had bought my drone in a worse season weather wise then in the middle of the Swedish summer ... been there done that, but were lucky until I had required proper knowledge about the risks flying at height & distance and got around the physics.

Good luck in your search fellow countryman, greetings from Örebro

 

[old man mavic]

i know you want to find your drone,but please don't put yourself at risk out on the ice good luck

 

[Olav van Gerven]

At this moment in the year, the lake will be solid frozen, besides that, Swedes (or do you say Sweets in englisch?) are familiar with icefishing

 

[kokesh]

Bad news I'm afraid. The wind at 460 meters height was 40 mph (18 m/s) out of the south, and at the end of the recorded flight the aircraft was moving due north at 6 m/s.

View attachment 94610

Looking at the battery depletion rate in RTH, and extrapolating to the smart battery autoland level at that height (22%) shows that it will have continued for another 420 seconds before commencing autoland. Extrapolating position based on the drift rate, followed by a 3 m/s descent rate, shows the following:

View attachment 94609

Plotting that on Google Earth, there's little doubt that it landed right in the middle of Ströms vattudal.

View attachment 94611

I'm criscrossing the lake. The area between red and green lines - is it most likely place to go? I'm circling around the point at the moment. Or can it be on the red line, between two crosspoints?

 

[kokesh]

I'm criscrossing the lake. The area between red and green lines - is it most likely place to go? I'm circling around the point at the moment.

Found nothing. Walked all over in big circles. I guess this is it.

 

[Olav van Gerven]

Have you seen traces of other people being on the ice? If so, ask in the local community if anybody found the drone, picked it up and forgot to report it as found. Sometimes, you will se there are honoust people.

 

[old man mavic]

the fact that it snowed has not helped the MM is so small you could be standing a couple of feet from it and not see it,i feel for your loss hope that maybe if the snow blows away later that you can have another look

 

[kokesh]

Have you seen traces of other people being on the ice? If so, ask in the local community if anybody found the drone, picked it up and forgot to report it as found. Sometimes, you will se there are honoust people.

No tracks from anyone, no one lives here. Maybe if our friends come for weekend, they can help me. How big area should i look at?

 

[zeusfl]

 

[sar104]

I'm criscrossing the lake. The area between red and green lines - is it most likely place to go? I'm circling around the point at the moment. Or can it be on the red line, between two crosspoints?

The yellow pin is the estimated landing point. There is likely to be an uncertainty of a couple of hundred meters - depending on how consistent the wind was over the lake.

 

[Prismatic]

At this moment in the year, the lake will be solid frozen, besides that, Swedes (or do you say Sweets in englisch?) are familiar with icefishing

Swedes, in English. As in, "All my wife's family are Swedes." (That's true for me, but none I know of have taken to ice fishing! ?)

 

[sar104]

I'm criscrossing the lake. The area between red and green lines - is it most likely place to go? I'm circling around the point at the moment. Or can it be on the red line, between two crosspoints?

The red line is the predicted flight track, and the green line is the ground track - it's a 3-D view. Perhaps it is easier to visualize in Google Earth:

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