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Should I trust these Coordinates or search elsewhere??

Yes - if uplink was lost at the same time, which it likely wasn't.
So at this point do you think that we should plot based on the speed at which it was drifting at the end of the log, or based on if RTH kicked in again and it started making headway? What was signal strength at according to Airdata?
 
Man, I just barely caught myself in time! I was making all my calculations in feet instead of meters again:rolleyes:.
 
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So at this point do you think that we should plot based on the speed at which it was drifting at the end of the log, or based on if RTH kicked in again and it started making headway? What was signal strength at according to Airdata?

May 20th, 2018 05:02PM | General / Overview | Drone Flight Log from DJI GO app, version 4.2.16 on Android | Total Mileage: 4,371 ft | United States | Airdata UAV

I was planning to bound those outcomes with no RTH until autoland through immediate RTH followed by autoland. That looks like either 2 m/s drift NE or 4 m/s flight SW. Over, say 150 s, that leads to an uncertainty of nearly 1 km.
 
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If it had commenced a further RTH would it not have climbed back up to 70m & regained connection? Perhaps because of so much downthrottle by operator RTH revises strategy to maintain current ALT.
OTOH if it did not climb on subsequent RTH and it was able to proceed to windward SW towards home I would have expected it to also reconnect. I guess there is a hill in the way though.

upload_2018-5-31_9-32-8.png

As you say though . Likely to be along the NE SW wind line dependent on what occurred after signal loss.
 
No - that's a contiguous line with a probability distribution defined by when (if) the uplink was lost.
I'm not even going to pretend to be smart enough to do what your doing.
I was wondering though, how you got 150 seconds. I assume its because your extrapolating line is compensating for the times in the battery info where downlink was lost and there is a large jump in the data. Mine turns out like this with roughly 227 of time between loss of signal, and critical battery autolanding. 227s.PNG
 
From G Earth one can see the obstructing terrain profile and that even after the descent the Mavic was still almost at 200 feet AGL when log ended. So still plenty of potential for it to be a long way from final point of the log.

upload_2018-5-31_12-25-9.png
 
I was not referring to your post. I was simply pointing out to OP that the chances of his Mavic being where he thought it was in the tree at the end of the flight log it pretty unlikely. Whilst 70' on the log might sound like it was just above the tree, it was in fact up at 200 AGL at this time.

But regarding your time to autoland extrapolation Q --- Your two times spread the very rough 2min 50sec (or 170 seconds) I estimated earlier. But anything is going to be a guess, because we cannot be sure of the power setting the mavic was on for the rest of the flight. Was it drifting downwind in an Atti mode hover or in RTH at high power?

IMO OP will either need to be very lucky to find this one. Hopefully his phone number is on it and someone hands it in.
 
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I was not referring to your post. I was simply pointing out to OP that the chances of his Mavic being where he thought it was in the tree at the end of the flight log it pretty unlikely. Whilst 70' on the log might sound like it was just above the tree, it was in fact up at 200 AGL at this time.

But regarding your time to autoland extrapolation Q --- Your two times spread the very rough 2min 50sec (or 170 seconds) I estimated earlier. But anything is going to be a guess, because we cannot be sure of the power setting the mavic was on for the rest of the flight. Was it drifting downwind in an Atti mode hover or in RTH at high power?

IMO OP will either need to be very lucky to find this one. Hopefully his phone number is on it and someone hands it in.
Lol sorry, I saw two alerts, one said quote the other said reply and I got them confused. I'll delete that post.
I don't think there is any indication of ATTI, the drifting was in P-GPS mode because for some reason the FC was only calling for about 15* of position holding tilt.
 
A more detailed look a the log reveals some good news:

2018-05-20_[17-02-30]_02.png

At the end of the recorded log the smart battery RTH level had risen to 29% - almost the battery percentage at that point (30%), which means that the aircraft was about to enter smart battery RTH, independent of signal loss. At that time it would have climbed to the RTH height of 70 m.

If we look at the period from 520 - 560 s, the aircraft was also in RTH mode at around 70 m. The green trace is the first derivative of distance with respect to time, i.e. the velocity away from the home point, and under those conditions it was approximately zero. For some reason it fared worse from 560 - 570 s, just before descending, after which it started to make progress home. Ignoring the 560 - 570 s anomaly, this suggests that at the RTH height it should have approximately held stationary in the wind. At the 10% smart battery land point, it will have started to descend in autoland, and should still have held position. This suggests that it should have auto landed quite close to the final recorded position - assuming that the wind profile didn't change over the next few minutes.
 
A more detailed look a the log reveals some good news:

View attachment 39100

At the end of the recorded log the smart battery RTH level had risen to 29% - almost the battery percentage at that point (30%), which means that the aircraft was about to enter smart battery RTH, independent of signal loss. At that time it would have climbed to the RTH height of 70 m.

If we look at the period from 520 - 560 s, the aircraft was also in RTH mode at around 70 m. The green trace is the first derivative of distance with respect to time, i.e. the velocity away from the home point, and under those conditions it was approximately zero. For some reason it fared worse from 560 - 570 s, just before descending, after which it started to make progress home. Ignoring the 560 - 570 s anomaly, this suggests that at the RTH height it should have approximately held stationary in the wind. At the 10% smart battery land point, it will have started to descend in autoland, and should still have held position. This suggests that it should have auto landed quite close to the final recorded position - assuming that the wind profile didn't change over the next few minutes.
Cool! Wouldn't even have thought to look at that, learn a new trick every time I'm on a thread with you.
Good luck finding it to the OP!
 
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...the aircraft was about to enter smart battery RTH, independent of signal loss. At that time it would have climbed to the RTH height of 70 m.
<snip>... at the RTH height it should have approximately held stationary in the wind. At the 10% smart battery land point, it will have started to descend in autoland, and should still have held position. This suggests that it should have auto landed quite close to the final recorded position...
If it climbed from 22m to 70m in the same vicinity of the final recorded position it should have regained signal should it not? Earlier it was lower at 60m and further away with a connection. The possibility of it being Closer, higher and more or less stationary for a couple of minutes with no connection at all seems a bit unlikely to me.
 
If it climbed from 22m to 70m in the same vicinity of the final recorded position it should have regained signal should it not? Earlier it was lower at 60m and further away with a connection. The possibility of it being Closer, higher and more or less stationary for a couple of minutes with no connection at all seems a bit unlikely to me.

You might expect that but either way - it was going into RTH and climbing very soon after the last data point whether due to lost uplink or smart RTH. Additionally, we don't know what the OP did with the controller in terms of maintaining orientation etc.
 
Yep, occurred to me OP may have thrown controller down in dismay at signal loss.

Then back into RTH like it was for most of the flight.

upload_2018-5-31_15-11-0.png
 
OP here. So say if the aircraft was to RTH which I believe it should have with the setting I had when it lost signal, where and how far would the aircraft had gone and where should i check? I have a new drone so im hoping to find it luckily landed on a roof
 
OP here. So say if the aircraft was to RTH which I believe it should have with the setting I had when it lost signal, where and how far would the aircraft had gone and where should i check? I have a new drone so im hoping to find it luckily landed on a roof

In post #31 I suggested that at RTH height it would effectively have held position against the wind, and eventually landed. Even slow drift over that period of time could lead to it having travelled some distance, but it suggests that the place to start looking is in the vicinity of its last recorded position, which was on Water St. at 38.0255 N, 121.9582 W.
 
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In post #31 I suggested that at RTH height it would effectively have held position against the wind, and eventually landed. Even slow drift over that period of time could lead to it having travelled some distance, but it suggests that the place to start looking is in the vicinity of its last recorded position, which was on Water St. at 38.0255 N, 121.9582 W.


I apologize I missed that post #31. Very helpful thank u!
 
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