DJI Mavic, Air and Mini Drones
Friendly, Helpful & Knowledgeable Community
Join Us Now

Lost Zoom. Need advice.

It wouldn't let me post them as a reply to you, so they're on the thread. It wouldn't even let me upload them together.

I'm a bit puzzled by the data. It shows the aircraft flying north up the beach for 2 minutes, as you described, but mostly directly over the beach. At just over 1 km the data stop, with no apparent signal issues leading up to that. Your course correction to the west is visible, but the last recorded point is over the beach.

1542843283147.jpeg

Are you saying that after disconnecting it moved further east over the water?

The disconnect is unexplained, in my opinion. The computed viewshed doesn't support the idea that the terrain caused the problem:

1542847466977.jpeg
 
I'm a bit puzzled by the data. It shows the aircraft flying north up the beach for 2 minutes, as you described, but mostly directly over the beach. At just over 1 km the data stop, with no apparent signal issues leading up to that. Your course correction to the west is visible, but the last recorded point is over the beach.

View attachment 53992

Are you saying that after disconnecting it moved further east over the water?

The disconnect is unexplained, in my opinion. The computed viewshed doesn't support the idea that the terrain caused the problem:

View attachment 53994
The whole flight was well out over water. As it departed, I got further from shore. I was flying between video feed and visually. When I noticed on the video feed that I was losing the white foam of the surf in the left of my video feed, i began shifting left to bring it back into the frame as it was my only point of reference being over water. I was flying to a shallow shipwreck a few hundred feet off shore near where I lost contact. I was bee-lining to that wreck which is marked by a flying American flag over the sunken wreck. When I lost sight of the flag in my video I immediately resorted to finding the surf foam as my reference to getting there. I had just barely gotten the foam in the view when I lost contact. I had now weak signal warning or RTH notification like I have typically experienced and knew this was serious. I raced down the beach with the controller in the air looking up at it showing "Connecting...." That's all it ever showed from then on. As for the disparity between map and my visual, I can only think of GPS error, map overlay slop, or maybe our beach has changed shape after our hurricanes.
 
Thank you for sharing your story.

The members are not bashing you
We live all over so cadents/dialect might be a factor
In were there answer might see harsh.
.
I agree with sar104 and meta4 assessment .
Sorry for your loss....

And you did the right thing not entering the water no drone is worth loss of life.

If you do purchase another DJI
Drone please make sure in your setting .
Change of forward avoidance setting to trigger RTH
(which is not a default setting)
And it is not clear whether you used your touch screen app or the controller to initiate RTH
(when in doubt use controller)

In general
Always make sure your battery is seated and don't fly with less then 20%
.
.....cR
.
 
Thank you for sharing your story.

The members are not bashing you
We live all over so cadents/dialect might be a factor
In were there answer might see harsh.
.
I agree with sar104 and meta4 assessment .
Sorry for your loss....

And you did the right thing not entering the water no drone is worth loss of life.

If you do purchase another DJI
Drone please make sure in your setting .
Change of forward avoidance setting to trigger RTH
(which is not a default setting)
And it is not clear whether you used your touch screen app or the controller to initiate RTH
(when in doubt use controller)

In general
Always make sure your battery is seated and don't fly with less then 20%
.
.....cR
.
Thanks for your input
 
As for the disparity between map and my visual, I can only think of GPS error, map overlay slop, or maybe our beach has changed shape after our hurricanes.
None of those would have made any difference.
I pointed that out to my case worker and she denied it being a contributing factor.
It might be interesting but it's not something that would affect RTH.
 
The default setting for loss of signal is RTH.
Almost no-one ever changes that setting.

Thanks, but I was asking the OP if he checked that setting. Seems to be the most logical reason why this happened.
 
The whole flight was well out over water. As it departed, I got further from shore. I was flying between video feed and visually. When I noticed on the video feed that I was losing the white foam of the surf in the left of my video feed, i began shifting left to bring it back into the frame as it was my only point of reference being over water. I was flying to a shallow shipwreck a few hundred feet off shore near where I lost contact. I was bee-lining to that wreck which is marked by a flying American flag over the sunken wreck. When I lost sight of the flag in my video I immediately resorted to finding the surf foam as my reference to getting there. I had just barely gotten the foam in the view when I lost contact. I had now weak signal warning or RTH notification like I have typically experienced and knew this was serious. I raced down the beach with the controller in the air looking up at it showing "Connecting...." That's all it ever showed from then on. As for the disparity between map and my visual, I can only think of GPS error, map overlay slop, or maybe our beach has changed shape after our hurricanes.

I've never seen that much error in a flight track. Something else is going on here.
 
The barometer and vision altitude data are also interesting:

View attachment 53995

The vision sensors detect a rapid change in altitude AGL at the end, down to just a few meters. Were there any structures on the beach?
Nothing. Line of sight. Flown here before and experienced an occasional weak signal and RTH activation but always able to immediately cancel RTH and continue flying. But that seemed routine for nearly everywhere I've flown.
 
If you do purchase another DJI
Drone please make sure in your setting .
Change of forward avoidance setting to trigger RTH
(which is not a default setting)

.
.....cR
.

What do you mean by that? OA doesn't trigger RTH at all. However OA can affect the outcome of RTH, including freezing in its tracks, particularly if it is a phantom obstacle.
 
I thought of OP having no downlink but not uplink, which indeed would have it hover, waiting for further instructions.
However that isn't as common with M2, and M2 seems to figure on that possibility and offer RTH.
Anyway, he at some point packed it in, not wanting to see the potential fate of the AC, so likely he did turn off the RC.
Even if he hadn't and he still had uplink or inadvertently cancelled RTH for the communication loss, there's still low battery RTH.
Since neither happened, the more likely scenario is a phantom obstacle that the AC had no idea how to get out of.
Perhaps RTH obstacle avoidance if it believes it is stuck is to yaw both ways to see if there's a way out from a different angle/direction.
 
  • Like
Reactions: Sberrada
review the Mavic Por Manual...(Go4app) Forward obstical sensor setting ...Hover.Go Over/Around,RTH
https://dl.djicdn.com/downloads/mavic/20170411/Mavic+Pro+User+Manual+V1.6.pdf
(pg22)
Could you point out where there is anything about Obstacle avoidance and RTH in the manual?
Page 22 there says:
The Mavic Pro is equipped with a Forward and Downward Vision System that constantly scans for obstacles in front of it, allowing it to avoid collisions by going around, over or hovering.
But I can't find anything in p22-25 that mentions anything about being able to change any settings or about an RTH option.
 
Lycus Tech Mavic Air 3 Case

DJI Drone Deals

New Threads

Forum statistics

Threads
131,382
Messages
1,562,609
Members
160,312
Latest member
Cryhav0c