I lost my drone (P3 standard) tonight

Joined
Nov 27, 2017
Messages
7
Reaction score
2
Age
53
OK, updated this post since yesterday with more data. I sincerely appreciate the help understanding where I went wrong. This is a good and supportive community. -Dan (updated post from 11/26 -- now 11/27 6:25pm pacific)

Screen Shot 2017-11-27 at 6.13.26 PM.png
Screen Shot 2017-11-27 at 6.05.04 PM.png
Hello folks-

Sad day for me. I live in a natural oak forest in Oregon. I've been flying for about 2 weeks in the DJI go app. All fine and very much enjoyed it. Tried my first couple of missions in litchi. Went fine. Thought I knew what I was doing. Did a mission hub for a 7 minute mission around my home and the drone lost signal and never came back.

So for the practical stuff:
- Is there any way to determine my drone's last position so I might be able to collect it?

In case curious: my mission had 9 waypoints all at 400'. My idea was to avoid hitting any obstacles of unknown height-- there are definitely trees nearby at 250'. My home has a large enough open area for take-off and landing. The mission was a loop ending right above where I started.

My theory of where I went wrong (just a guess). First my mission had do-nothing (must be default because I didn't assign it) at end of mission. This likely not a problem on its own because mission end was over my home location. I had a good home point and good GPS 11+ satelites at launch. My controller said disconnected after a minute or so of 7 minute flight (expected). My thought is I must of accidentally tapped a up/down/right/left stick near the time the drone lost signal-- causing it to hover (don't know). Since RTH wasn't selected (error on my part) in the mission, it likely hovered until emergency landling.

I don't really know what happened. I normally do lose video and later controller signal in my home area even in .5 mile area because of the tree canopy and terrain. Litchi shows a position for my drone. i tried to hike there tonight- very rough mountain terrain. Didn't make it.

So thoughts:
- Is it likely last position Litchi had is accurate given that it lost signal? i.e. If I really hike/climb to that location do I have any reason to believe it accurate? My concern is that this may be last position it had signal and not real location.
- In general is here any methods to find? My mission had 9 waypoints forming a circle with the last point where I started (also the H - home position.) I thought when battery got low RTH would happen but it did not.

Anyway, thoughts/advice welcome.

-Dan

PS: I'm running latest Litchi bought for black friday sale this weekend. Drone running one back firmware from 1.9. I had been alerted to 1.9 but was waiting a bit to see how people like.

And also FYI- I flew about 4pm today (11/26). It was daylight (mostly) when the craft was lost.
Screen Shot 2017-11-27 at 6.10.25 PM.png


Flight Log: DJI Flight Log Viewer - PhantomHelp.com
Here's a link to the mission: Mission Hub - Litchi
 
Last edited:
Joined
Jul 13, 2017
Messages
120
Reaction score
52
Location
Michigan
Sorry to hear that. If you have a flight log available to post, many folks here are good at analyzing them.
 

Meta4

Premium Pilot
Joined
Jan 8, 2014
Messages
15,200
Reaction score
9,142
Is it likely last position Litchi had is accurate given that it lost signal? i.e. If I really hike/climb to that location do I have any reason to believe it accurate? My concern is that this may be last position it had signal and not real location.
Of course it the last position that the app got from the drone - right before you lost signal.
After losing signal, it's not going to know where the drone ended up.

Go to: Go to DJI Flight Log Viewer
... and follow the directions to get your Litchi flight record.
Upload it to that site and post a link here.
Also if you can post a screenshot of the Litchi mission planning and a location people can find in Google Earth, perhaps someone might be able to work out what happened.
 
Joined
Aug 15, 2016
Messages
3,591
Reaction score
1,540
Age
42
Sorry to here that buddy. Any chance you could have accidentally set another way point as you tapped the screen? It could be so many scenarios for it not to come back. Thankfully your mission is in a loop so depending how much area it covered you should come across it. Don’t give up tho. My P3A got lost for 24 hours and these guys helped get it back. When you went tracking to find it, did you bring the controller with you to try and pick up signal?
 
Joined
Jun 11, 2016
Messages
3,513
Reaction score
1,995
Location
Northwest USA
What was the RTH alt at? And also in addition to uploading to the viewer upload your litchi mission so we can look at it.
 

Fly Dawg

"Electricity is really just organized lightning"
Premium Pilot
Joined
Apr 29, 2016
Messages
4,655
Reaction score
2,076
Location
Watkinsville, Georgia
My controller said disconnected after a minute or so of 7 minute flight (expected). My thought is I must of accidentally tapped a up/down/right/left stick near the time the drone lost signal-- causing it to hover (don't know). Since RTH wasn't selected (error on my part) in the mission, it likely hovered until emergency landling.
First point and this is neither here nor there really, but there is no RTH selection in a Litchi mission. End of mission is either, land or hover, that's it. There is really no way to know why the mission did not complete as programmed without taking a look at the flight logs as @Meta4 mentioned above. At the very least, you would be able to follow the flight profile to the last known location. You would also need to fully review your mission profile for any errors. Sorry for the loss.
 
Joined
Jun 11, 2016
Messages
3,513
Reaction score
1,995
Location
Northwest USA
RTH issue might be involved if the mission was interrupted or toggled out of F mode. The altitude set would then be relevant. Otherwise either a mis-tapped "Extra way point" or a "end of mission setting" would be in play.
 
  • Like
Reactions: Pharm
Joined
Jul 26, 2017
Messages
2,305
Reaction score
1,238
Location
Irvine (Orange County) CA
A couple of things come to mind:

1) Battery upon take off
2) Speed settings for your mission
3) Wind speed at 400 feet

As others have suggested, posting your flight log and even a link to your mission may reveal additional clues.

At 400 feet it most likely did not encounter any obstacles, but could have had some difficulty if wind speeds were high preventing the AC from completing the mission before battery rn out, in which case it would auto-land.
 
Joined
Jun 14, 2016
Messages
1,744
Reaction score
791
Age
64
I can think of several possible scenarios but until the logs are posted, it’s all guesswork.
 
Joined
Aug 15, 2016
Messages
3,591
Reaction score
1,540
Age
42
So near to the hospital there is a slight chance the signals from the hospital may have interferes with the compass sending it into compass error and ATTI mode. However I have no idea if the mission will continue or RTH when compass error is gone.
 
Joined
Feb 6, 2017
Messages
189
Reaction score
81
Hello folks-

Sad day for me. I live in a natural oak forest in Oregon. I've been flying for about 2 weeks in the DJI go app. All fine and very much enjoyed it. Tried my first couple of missions in litchi. Went fine. Thought I knew what I was doing. Did a mission hub for a 7 minute mission around my home and the drone lost signal and never came back.

So for the practical stuff:
- Is there any way to determine my drone's last position so I might be able to collect it?

In case curious: my mission had about 7 waypoints all at 400'. My idea was to avoid hitting any obstacles of unknown height-- there are definitely trees nearby at 250'. My home has a large enough open area for take-off and landing. The mission was a loop ending right above where I started....

You most likely hit a tree. I saw a post similiar to this a couple of weeks ago.

Even if you set a rth of 400 feet to avoid obstacles in your flight path, a tree that is 200 feet tall will bring down your Phantom if the ground elevation of the tree's location is 300 feet higher than your launch elevation.

Sorry for your loss. Hopefully you can find it.

Review your flight path and see if you can find the first likely area where the ground elevation + tree and your mission altitude conflict.

Good luck with your search
 
  • Like
Reactions: Oso and LarBear360

Meta4

Premium Pilot
Joined
Jan 8, 2014
Messages
15,200
Reaction score
9,142
My P3 pro lost signal by the hospital. I was **** near 30k feet out. The blue line is the path it was rth... second pic was the last connection I had with the aircraft. Haven’t seen it since, despite multiple searches.
Have you looked at the flight data to see what story it tells?
There's a good chance it will explain the mystery and possibly point to a likely search area.
DJI Flight Log Viewer

ps .. at that height, the hospital would have had no effect on your flight.
 
Joined
Nov 27, 2017
Messages
7
Reaction score
2
Age
53
What was the RTH alt at? And also in addition to uploading to the viewer upload your litchi mission so we can look at it.
I updated my original post from yesterday with requested data. The mission was a loop-- but my mission final action was set incorrectly to "None" -- I'd of preferred RTH. If the loop had completed the final waypoint was very close to starting point.
 
Joined
Nov 27, 2017
Messages
7
Reaction score
2
Age
53
RTH issue might be involved if the mission was interrupted or toggled out of F mode. The altitude set would then be relevant. Otherwise either a mis-tapped "Extra way point" or a "end of mission setting" would be in play.
Definitely didn't toggle out of F mode. Had read manuals carefully pre-flight.

-Dan
 
Joined
Nov 27, 2017
Messages
7
Reaction score
2
Age
53
Sorry to here that buddy. Any chance you could have accidentally set another way point as you tapped the screen? It could be so many scenarios for it not to come back. Thankfully your mission is in a loop so depending how much area it covered you should come across it. Don’t give up tho. My P3A got lost for 24 hours and these guys helped get it back. When you went tracking to find it, did you bring the controller with you to try and pick up signal?

Yes, my wife and I tried over tough terrain to hike to signal lost position. All through brambles and whatnot (blackberrys, poisen oak and the like). We hiked for about 1.5 hours with controller in hand trying to get my blue dot (controller) to overlay last position. Couldn't make it to that exact spot due to elevation gain. I'm pretty familiar with this area and -- of course since I lost the drone can and am sometimes wrong-- but I suspect 400' was enough altitude to avoid trees in the area. The highest point I've witnessed is about 250'-- but it's fair to say the land around here varies in elevation and relative tree height could of got me.

With regard to touching screen-- nope. I will admit I could of gently tapped a stick. But once it started its mission (I hit play and watched it go off) I just stood as still as possible. I did not touch screen (and I did review mission after load before hitting play). Right about the time it flew out of range "disconnected" i may of touched a stick. After 7 minutes passed (and it should be back), I manually invoked RTH with S2 flick. I then got it my truck and drove the path to see if I could get signal. Window down, controller held out window beeping. At a couple of intervals tried RTH again before my ~27 minutes of battery died. Went home for the last few minutes and waited in driveway to see if it would return. -Dan
 

Meta4

Premium Pilot
Joined
Jan 8, 2014
Messages
15,200
Reaction score
9,142
You were flying a Standard, so losing signal at the distance you did is not unexpected.
I suspect 400' was enough altitude to avoid trees in the area. The highest point I've witnessed is about 250'-- but it's fair to say the land around here varies in elevation and relative tree height could of got me.
We only have very limited information but looking at the route you set, I see one obvious problem.
i-P9nGGn5-X2.jpg

Your home point is at about 940 feet altitude and there is a point on the route where Google Earth shows an elevation of 1346 ft (and there would be tree height to add to this).
400 ft would not be sufficient to clear this high point.
If everything went without a problem, when your Phantom got to this high ground, it will have crashed.
Here's a rough location for your search area.
You can refine it by zooming in on your Litchi flight plan to see the track it would have taken here.
i-twhp2mR-XL.jpg

Search from the south as the drone probably hit a tree before it got to the higherst land.
It's a little less dense than some of the other parts of the route.
Good luck with the search
 

sar104

Dic mihi solum facta, domina.
Premium Pilot
Joined
Mar 22, 2014
Messages
5,303
Reaction score
2,701
Location
Los Alamos, NM.
You were flying a Standard, so losing signal at the distance you did is not unexpected.

We only have very limited information but looking at the route you set, I see one obvious problem.
i-P9nGGn5-X2.jpg

Your home point is at about 940 feet altitude and there is a point on the route where Google Earth shows an elevation of 1346 ft (and there would be tree height to add to this).
400 ft would not be sufficient to clear this high point.
If everything went without a problem, when your Phantom got to this high ground, it will have crashed.
Here's your search area.
You can refine it by zooming in on your Litchi flight plan to see the track it would have taken here.
i-twhp2mR-XL.jpg

Search from the south as the drone probably hit a tree before it got to the higherst land.
It's a little less dense than some of the other parts of the route.
Good luck with the search

Agreed. The 400 ft relative altitude was not adequate for the terrain:

screenshot61.jpg
 

sar104

Dic mihi solum facta, domina.
Premium Pilot
Joined
Mar 22, 2014
Messages
5,303
Reaction score
2,701
Location
Los Alamos, NM.
Here is the kml description of the flight path with altitude defined absolutely as 400 ft above takeoff point. I added .txt since apparently .kml files are not allowed for upload.
 

Attachments

  • flight_path_400ft.kml.txt
    2.9 KB · Views: 400

Recent Posts

Members online

Forum statistics

Threads
142,466
Messages
1,462,564
Members
104,284
Latest member
schoolnetindialtd