Dreaded lost drone post **FOUND**

[Wahoo_Ace]

So I have been scouring the internet for help on this for over a week now and I just can't give up (even though my wife says to move on). Background on this story:
I went to fly what was going to be really awesome mission using LITCHI last week. It had just snowed and I was going to fly along a plotted path down a creek. I flew it once before and knew that I was going to probably lose signal at some point but knew to just wait it out and I would regain signal....well, it didn't go as planned. I was following my bird and had just came across several bald eagles, one of which was flying below me (NO I WAS NOT CHASING THEM). I came to a bend in the creek and signal was lost. It had started to snow a little bit but nothing major. I tried moving around to hopefully help regain signal and also put on my parabolic antenna attachments to hopefully help. No dice. 20 minutes went by, then 30, I knew it was out of juice at this point and I was looking at a recovery mission. I trekked over fields and looked EVERYWHERE!! I have followed the path that was in litchi to no avail. Of course since it had been snowing, I very well could have walked past it flipped over in the snow somewhere.
Here is the airdata info:
Airdata UAV - Flight Data Analysis for Drones

I have attached a screenshot of the litchi path and will share the kml file when at my computer. I lost signal between 11 and 12.

When uploaded into Google earth, I think I may be in the trees. I went back out with my replacement drone (phantom 4 advanced) and tried to fly the final 3 waypoints but don't have the guts. It looked like I was going to run into the trees!! I know I screwed up and didn't set my final waypoints high enough and had WAAAY to much distance between them. I just want some closure on this **** thing! It doesn't appear that I have went for a drink as my last transmission was just a typical lost signal and not a crazy spinning out of control!

Thanks for your help and please let me me know what more information you may need!!!

 

[MotorCycle-Man]

Beware....somethings wrong here....the air data is NOT RIGHT !

 

[Wahoo_Ace]

Beware....somethings wrong here....the air data is NOT RIGHT !

How so? Very new to this!!

 

[charlieb4]

Why is that I click on his airdata, it sends me to Youtube?????? The HUNGARIAN TRUCKERS...smh.

 

[Meta4]

Thanks for your help and please let me me know what more information you may need!!!

Don't worry about Airdata (it's not very good for incident investigation anyway).

Go to DJI Flight Log Viewer
Follow the instructions there to upload your flight record from your phone or tablet.
Come back and post a link to the report it provides

 

[Wahoo_Ace]

My apologies! I am not a spammer! Apparently it didn't copy correctly! Airdata UAV - Flight Data Analysis for Drones

I will upload the dji flight log as well.

 

[sar104]

My apologies! I am not a spammer! Apparently it didn't copy correctly! Airdata UAV - Flight Data Analysis for Drones

I will upload the dji flight log as well.

You will need to post a link to the Litchi mission in order for anyone to try to calculate what happened here.

 

[Wahoo_Ace]

Here is the Litchi mission to start:
Mission Hub - Litchi

Itunes has switched things up in 12.7 so I am working on getting the flight data now...

 

[sar104]

Here is the Litchi mission to start:
Mission Hub - Litchi

Itunes has switched things up in 12.7 so I am working on getting the flight data now...

It looks like your flight was probably fine while over the water, but on the direct line return the ground clearance drops to less than 30 ft. If those trees are higher than that then it likely hit one coming back. I'd check that line.

 

[Wahoo_Ace]

I think this is what you need. It really doesn't show much other than it just disappears!!
DJI Flight Log Viewer - PhantomHelp.com

 

[Wahoo_Ace]

It looks like your flight was probably fine while over the water, but on the direct line return the ground clearance drops to less than 30 ft. If those trees are higher than that then it likely hit one coming back. I'd check that line.

View attachment 95109

That is what I was thinking. I went out the other day thinking it may be in the first line of trees but I could not find it. They are definitely higher than 30 feet. The snow is melting fast so I may have to go back out there!

 

[sar104]

I think this is what you need. It really doesn't show much other than it just disappears!!
DJI Flight Log Viewer - PhantomHelp.com

Right - that doesn't give any clues on what happened. As I mentioned above, your hypothesis that it hit trees on the return seems most likely.

 

[sar104]

That is what I was thinking. I went out the other day thinking it may be in the first line of trees but I could not find it. They are definitely higher than 30 feet. The snow is melting fast so I may have to go back out there!

Then that's almost certainly what happened. Good luck with your search.

 

[Wahoo_Ace]

It looks like your flight was probably fine while over the water, but on the direct line return the ground clearance drops to less than 30 ft. If those trees are higher than that then it likely hit one coming back. I'd check that line.

View attachment 95109

Can you show me how you can tell it was less than 30'? I know, I know, if I can't figure this out then I shouldn't be using Litchi! Trust me, the best way to learn is to screw something up! Thank you!!

 

[sar104]

Can you show me how you can tell it was less than 30'? I know, I know, if I can't figure this out then I shouldn't be using Litchi! Trust me, the best way to learn is to screw something up! Thank you!!

What I did was to export your Litchi mission as a 3-D kml file, import it into Google Earth, then duplicate it and clamp the duplicate track to ground. Then you can compare the flight track and ground track elevation profiles, either manually in GE, which is what I did in this case since it was pretty simple, or you can compute an actual AGL dataset as described in this post.

 

[Wahoo_Ace]

What I did was to export your Litchi mission as a 3-D kml file, import it into Google Earth, then duplicate it and clamp the duplicate track to ground. Then you can compare the flight track and ground track elevation profiles, either manually in GE, which is what I did in this case since it was pretty simple, or you can compute an actual AGL dataset as described in this post.

Amazing. Here I thought I could just upload this stuff and away I go! Great write up!

It boggles me that the drone wasn't right in the start of the tree line but I will go look again. I really screwed up by not setting waypoint 15 to a much higher elevation for the trip back home. I appreciate the help!

 

[Fly Dawg]

I agree with the above theories, that you didn't clear the trees on the return at Waypoint 15. This is neither here nor there at this point, but 50ft in altitude is far too low. And I will ask @sar104 to verify this, but if this is the correct altitude in feet, then it's even worse. Otherwise, the tree line would be the first choice.

 

[Wahoo_Ace]

I agree with the above theories, that you didn't clear the trees on the return at Waypoint 15. This is neither here nor there at this point, but 50ft in altitude is far too low. And I will ask @sar104 to verify this, but if this is the correct altitude in feet, then it's even worse. Otherwise, the tree line would be the first choice.

View attachment 95110

My plan was to fly down the middle of the creek low and then come out at the end. There is a steep cliff on each side of the creek at the end points. I went back out with my new drone and ran a mission from point 15 to 16. However, when I ran the mission, the bird was JUST above the first trees and I aborted as not to lose a second drone up in the trees! I am pretty positive it made it out from above the water.
Once I find this, I will post the video as it should be epic!

 

[charlieb4]

Right - that doesn't give any clues on what happened. As I mentioned above, your hypothesis that it hit trees on the return seems most likely.

Hi,
Looking at this, it show that the drone could have landed in the river. (which I’m hoping not for ur stake) it shows that it could have, on the field side. Across the river from the tall trees. The side of the river on the Waverly St. side. I’m bringing this up, in case u do not find ur drone. I sure hope that u do find ur drone, so u can continue to fly, and a happy camper.

 

[Wahoo_Ace]

Hi,
Looking at this, it show that the drone could have landed in the river. (which I’m hoping not for ur stake) it shows that it could have, on the field side. Across the river from the tall trees. The side of the river on the Waverly St. side. I’m bringing this up, in case u do not find ur drone. I sure hope that u do find ur drone, so u can continue to fly, and a happy camper.

Can you circle where you think it might be? Does it matter that when I tried to run the final steps of the mission, it was above the banks of the creek?