Lost signal, RTH, aircraft lost...possibly crashed in the river

[Paulark]

No luck so far. The divers looked yesterday and the bottom of the river is smooth right there. So there's nothing for it to have wedged in. So that possibility is now null and void. I'm going to go up on the ridgeline and look some more today, but I fear now that all hope is lost ?

 

[sar104]

No luck so far. The divers looked yesterday and the bottom of the river is smooth right there. So there's nothing for it to have wedged in. So that possibility is now null and void. I'm going to go up on the ridgeline and look some more today, but I fear now that all hope is lost ?

Don't forget that although the aircraft will sink, it will still drift with the current while doing so, possibly some distance.

 

[Paulark]

I still haven't had any luck. I haven't walked that red line between home and the point where it dropped the signal except for up on that ridgeline. Even though I had the RTH set to 30m, and the trees on the ridge are higher, I think the greatest possibility is that with 36% battery, the obstacle avoidance system got it over the ridge and it probably made it back to the home point and crashed into the river.

Not sure if I should reach out to DJI support or not. I guess it's worth a shot since I purchased the care refresh. Thoughts?

 

[MAvic_South_Oz]

Not sure if I should reach out to DJI support or not. I guess it's worth a shot since I purchased the care refresh. Thoughts?

Can't hurt, but of course they will likely say no without the 'body'.
But they might offer a small discount on a new aircraft and battery too, so ask away.

 

[Dakarenduro]

Sorry to hear about the loss. Sucks. Originally reading the title I figured it was another Mini lost, so you caught my interest when I read it was an Air!

Hope you get something from DJI in the way of a discount. Good luck!

 

[sar104]

I still haven't had any luck. I haven't walked that red line between home and the point where it dropped the signal except for up on that ridgeline. Even though I had the RTH set to 30m, and the trees on the ridge are higher, I think the greatest possibility is that with 36% battery, the obstacle avoidance system got it over the ridge and it probably made it back to the home point and crashed into the river.

Not sure if I should reach out to DJI support or not. I guess it's worth a shot since I purchased the care refresh. Thoughts?

Looking again at the battery data, the remaining battery was marginal to be back to the recorded home point, especially if it had to climb to avoid terrain and trees. At best it looks like it would end up autolanding around 500 m short. It might also be worth a quick look in the open ground between the two pins shown below - the red circle is the 500 m distance from the home point:

 

[Paulark]

Wow...thanks a lot for the data analysis! That's some nice work, sir. Hopefully I can get back up there in the next few days to give it another go.

Edit: You may really be onto something here. I just calculated it a little bit differently, but using the same principle...and got it coming up even shorter. Will show after breakfast.

 

[Paulark]

5479ft or 1770m was the max distance I calculated using 8m/s as my RTH velocity (that's what it is in most youtube videos), the time remaining is 289s (from the red/amber/green bar at the top of the flight record video), and 36% battery remaining. The aircraft starts to try and land with the final 10% battery, so that knocks it down to 26% battery. Please see photo for further explanation.

Using these parameters, I calculated that it didn't even get close...so it seems I have more work to do upon that hill!

 

[sar104]

5479ft or 1770m was the max distance I calculated using 8m/s as my RTH velocity (that's what it is in most youtube videos), the time remaining is 289s (from the red/amber/green bar at the top of the flight record video), and 36% battery remaining. The aircraft starts to try and land with the final 10% battery, so that knocks it down to 26% battery. Please see photo for further explanation.View attachment 99523

Using these parameters, I calculated that it didn't even get close...so it seems I have more work to do upon that hill!

You are better off looking at the data in the first graph in post #26, which takes into account the autoland issue.

 

[Paulark]

You are better off looking at the data in the first graph in post #26, which takes into account the autoland issue.

Copy that. Probably better than pulling out percentages at the end. Thanks for your time and help!