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Lost Mavic mini

Tares81

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Hi,
We lost our new Mavic mini last Sunday. Our son was flying too high and far when winds were too strong. We could see it and were trying to land it but winds too strong. Last known location it is 12m up in the air so we have no landing location. We have searched the surrounding fields for hours but no luck. Would anyone here be able to help with a possible location based on flight data?
Thanks and ?View attachment 103156View attachment 103157
 
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Here's a summary of the flight:

The drone was being blown backwards at 2.5-3.5 metres/sec when it was hovering at 20 metres.
But in the last five seconds of the flight data you descended to 13 metres and the speed reduced to 0-0.5 metres/sec in the lower wind speed.

It's difficult estimate a likely search area because we don't have enough data to tell at what the battery was running down.

I'd use 1% per 12 seconds as a rough idea which would mean the drone would not reach critical low voltage until 540 seconds after signal was lost.
But the big issue is that we only have a couple of seconds of data at the lower altitude, so we cannot be sure of the speed of drift.
The ground level is falling away in the direction the drone was being blown and there don't appear to be any trees for it to hit, so it's not going to have been caught by an obstacle.

The drone will possibly have blown further to the NNE, but only slowly.
It may have even made some headway toward the homepoint if the wind dropped enough.
I wouldn't really like to suggest a likely search area given the uncertainties.
Perhaps this one is a worthy challenge for @sar104 to exercise his puzzle solving skills ?
 
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Here's a summary of the flight:

The drone was being blown backwards at 2.5-3.5 metres/sec when it was hovering at 20 metres.
But in the last five seconds of the flight data you descended to 13 metres and the speed reduced to 0-0.5 metres/sec in the lower wind speed.

It's difficult estimate a likely search area because we don't have enough data to tell at what the battery was running down.

I'd use 1% per 12 seconds as a rough idea which would mean the drone would not reach critical low voltage until 540 seconds after signal was lost.
But the big issue is that we only have a couple of seconds of data at the lower altitude, so we cannot be sure of the speed of drift.
The ground level is falling away in the direction the drone was being blown and there don't appear to be any trees for it to hit, so it's not going to have been caught by an obstacle.

The drone will possibly have blown further to the NNE, but only slowly.
It may have even made some headway toward the homepoint if the wind dropped enough.
I wouldn't really like to suggest a likely search area given the uncertainties.
Perhaps this one is a worthy challenge for @sar104 to exercise his puzzle solving skills ?

Thank you for taking time to try @Meta4! And if any other suggestions here of a possible landing location please let me know.
 
Unfortunately this is one of those cases that doesn't have enough data for even a rough estimate. After losing connection the aircraft will have climbed to the set RTH height of 120 m (more on that later) where the autoland battery level is 10%. Extrapolating the battery depletion rate to that level indicates that autoland would have started at 885 seconds. That's 390 seconds of unlogged flight.

Battery.png

The wind speed is the problem. At ground level it appears to have been just a couple of m/s. At 24 m it was around 12 m/s, which is why the aircraft was being blown at around 4 m/s (it can only hold in wind speeds up to 8 m/s). The wind speed at the RTH height of 120 m is unknown, but probably significantly higher given the gradient from 0 to 20 m. So we can assume that it would be blown downwind at greater than 4 m/s, and possibly much faster. At 4 m/s that would put it over 1.5 km from it's last recorded point when it started to autoland. On the other hand, if the wind speed at 120 m were double that at 24 m, then that would put it 6.25 km downwind. You could walk the line of the estimated wind direction perhaps, but the chances of locating it in that terrain are negligible, unfortunately.
 
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The wind speed is the problem. ... we can assume that it would be blown downwind at greater than 4 m/s, and possibly much faster.
At 4 m/s that would put it over 1.5 km from it's last recorded point when it started to autoland.
Since the Irish Sea is only 1.1 kilometres downwind from the last recorded location ......
I probably don't need to spell it out.
 
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