Lost my Mavic - Need help to locate it

[valterS]

Hello guys. My first post here ... Discoverd today this forum.

I lost my mavic a few days ago, after flying in a windy day. The wind was so strong that pushed it away, even in sport mode, with me pushing the controls to take it back, but no success... I panicked and did not remember there was a "back to home" button on the remote. I think that wouldn't help anyway, as I was trying to bring it back by "hand" and it was going far and further... One of the reasons that it went so far was while I got into my car and drove closer to a cliff, where I could have sight view of the drone. While I was driving it went even further, because I was not trying to bring it back while driving.

When I realized that I would not be able to bring it back, as it already was 1700m from the home point, I tried to land it where it was, but once again, I forgot the "magic" button on the phone screen, that makes it land safely, and I have tried to land it pushing it down. When it was almost hitting ground, it lost signal... But I thought it had landed. I turn off the remote, and I went to the latest GPS position recorded, but was not able to find the drone.

So now I ask for your help.

Here is the flight log
DJI Flight Log Viewer - PhantomHelp.com

According to some calculations I have done, and according the the speed it was and remaining battery, it must be landed about 2km to 3,5km away.

It is raining a lot today :-( , so I couldn't try to find it yet. It has past already 8 days, I only today I decided it is worth the try.

I would appreciate your help to analyze my logs and point where I should look for.

Thank you very much

 

[lisadoc]

There's a few questions you probably need to answer first, before a good educated guess is forthcoming.

1) Did you have RTH set for signal loss?
2) What was your RTH height set at?
3) What percentage was your critical battery set to?

My guess would be that it lost the signal at the last location. Since it wasn't in landing mode, it hovered until the "lost signal" setting took over. If you had it set for "Land" or "Hover", it likely would have been right there at the last known location, as even with Hover it would have stayed there until critical battery, then landed.

If it was set for RTH, the important thing would have been the height set. With the wind, the higher the RTH altitude was set at, the farther northeast it would have been taken. If your critical battery was set at 10%, it probably would have gone up, been moved NE for 40% or so of the battery, then landed at 10%. The time needed to achieve RTH height and the final percentage for critical battery landing will determine the distance to the NE it traveled. Your red-circled area may be close, but those settings can change the distance quite a bit.

 

[stratos]

Sorry for your loss mate. Now, you learned the hard way. If you didnt land its likely that went you lost connection the quad tried to go back home. Now with the strong wind probably just landed in another area while trying to find the wind.

 

[sar104]

It certainly came close to landing - VPS shows it was within 1.5 m of the ground - but no definite evidence that it landed.

If it did not land, and lost uplink, it would have gone to RTH and ascended to the RTH altitude that was set at the start of the flight of 30 m above takeoff point, which would have taken it back up to around 130 m above the ground. You would likely have regained the link, but you mentioned that you had turned off the RC. That was a mistake. The winds were strong up there. Airdata estimates just under 10 m/s, which a Mavic should be able to combat (just). But if you look at the period from 100 - 200 seconds, when you were applying no stick inputs, the aircraft was pitched at around 15° and being blown backwards at over 5 m/s.



The wind is also obviously gusting.

If you consider the rate of battery depletion, and assume a critical landing level of 15% (that's a guess, not knowing what you set), we can estimate how much longer it may have been able to fly:


That suggests around 800 seconds total, or another 400 or so seconds. Unfortunately it appears that it would have made no headway back home in RTH, since it would be limited in pitch to around 15° and that was inadequate to hold station, let alone return. If it were blown at 5 m/s downwind then that would put it another 2 km to the north at critical battery (close to where you estimated), but there are too many unknowns here to put much faith in that estimate.

 

[valterS]

I did some search today on the red area, using a P3 and also a powerful binoculars ( 25x ). Found nothing.

It has past already 9 days... Someone that works on the planting may already have found it.
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Anyone knows what is the default RTH settings? I never changed it.

 

[msinger]

Anyone knows what is the default RTH settings? I never changed it.

The default RTH settings are for the Mavic to return home at an altitude of 30 meters. Since your RTH setting was set to 30 meters, your Mavic would have ascended to 135 meters before it started returning home (since it was flying at -105 meters when the remote controller signal was lost). The wind must have been quite ferocious at that altitude.

 

[sar104]

I did some search today on the red area, using a P3 and also a powerful binoculars ( 25x ). Found nothing.

It has past already 9 days... Someone that works on the planting may already have found it.
---

Anyone knows what is the default RTH settings? I never changed it.

I stated the RTH set for this flight in post #4 - it was 30 m, which is also the default.