I Lost my P4P

[abwRN]

Hello, I still did not understand fom where exactly you launched your aircraft for this last fatal mission. Was it from what is said "waypoint 3" in your first screenshot, message 1, or either from what is said waypoint 1 or an other place ?
If it was at waypoint 3, how did you fly from waypoint 3 to the vicinity of waypoint 1 in order to start the mission ? As far as I know Litchi, the app refuses to start a mission when home point is too far away from the first waypoint of the mission. Here, waypoint 1 was distant about 2km (6600 feet) from waypoint 3..!

And why didn't you upload the fight data here :
https://www.phantomhelp.com/LogViewer/Upload/
For sure they are still in your device if you didn't reset it since this flight.
Without these elements, we can only speculate on what happened.

There were only 3 waypoints. (Waypoint 3 is really where it launched from..Home) Litchi would not let me upload the mission to the hovering drone with only 2 waypoints due to distance between them so I move Waypoint 2 to where you see it and created Waypoint 3 basically on top my house.Then, I sent the mission to the Bird and off it went.

I have the first part of the mission in .csv and will upload today. Remember, it only is the first part because that's where it lost signal and continued its mission alone. We know it arrived at waypoint 2 because our friend waved to it and it then turned and headed back home according to her. I will upload it soon...

 

[Peio64270]

There were only 3 waypoints. (Waypoint 3 is really where it launched from..Home) Litchi would not let me upload the mission to the hovering drone with only 2 waypoints due to distance between them so I move Waypoint 2 to where you see it and created Waypoint 3 basically on top my house.Then, I sent the mission to the Bird and off it went.

I have the first part of the mission in .csv and will upload today. Remember, it only is the first part because that's where it lost signal and continued its mission alone. We know it arrived at waypoint 2 because our friend waved to it and it then turned and headed back home according to her. I will upload it soon...

Yes, I understand. Thus, you launched at waypoint 3 and then the bird flew straight by itself to waypoint 1 where the mission begins. It would be useful to know at what altitude you sent it hovering before starting the mission because it seems that it could reach waypoint 1 without issue. Then the mission actually started at waypoint 1 (not waypoint 2 as you write above ??) where your friend saw it turning and coming back.
Is this right ?

If so, were you watching at the live video for the whole flight ? What did you see till the moment the bird disconnect ?
I am guessing that disconnection was the moment the drone hit something and/or fell down.
That's why it would be very useful to know what you could see in your device during this flight and, more important, to get the log analyzed in PhantomHelp. With these data, I think that it is possible to locate more or less precisely where your drone is...

 

[abwRN]

Yes, I understand. Thus, you launched at waypoint 3 and then the bird flew straight by itself to waypoint 1 where the mission begins. It would be useful to know at what altitude you sent it hovering before starting the mission because it seems that it could reach waypoint 1 without issue. Then the mission actually started at waypoint 1 (not waypoint 2 as you write above ??) where your friend saw it turning and coming back.
Is this right ?

If so, were you watching at the live video for the whole flight ? What did you see till the moment the bird disconnect ?
I am guessing that disconnection was the moment the drone hit something and/or fell down.
That's why it would be very useful to know what you could see in your device during this flight and, more important, to get the log analyzed in PhantomHelp. With these data, I think that it is possible to locate more or less precisely where your drone is...

You are partially correct. I watched the video as it flew to Waypoint 1 from my home(Waypoint 3) and it lost contact about 1/3 of the way there. A little before where you see waypoint two. Our friends at Waypoint 1 saw it "begin its mission" so we know it kept flying long after we lost video contact.

I tried uploading the .csv to your link but that didn't do anything. Here it is in Airdata.com http://app.airdata.com/main?share=RsGIyd The only way I think this will help is that the bird would have returned home flowing this same track(Roughly)

 

[abwRN]

Oh..Also..The last Video I posted was "rejected" from youtube for some dumb reason..Probably the title... I appealed the decision and they should correct it soon.


PS- For what its worth, I won the appeal and that video is back up..

 

[Peio64270]

You are partially correct. I watched the video as it flew to Waypoint 1 from my home(Waypoint 3) and it lost contact about 1/3 of the way there. A little before where you see waypoint two. Our friends at Waypoint 1 saw it "begin its mission" so we know it kept flying long after we lost video contact.

I tried uploading the .csv to your link but that didn't do anything. Here it is in Airdata.com http://app.airdata.com/main?share=RsGIyd The only way I think this will help is that the bird would have returned home flowing this same track(Roughly)

Wow, I did not understand you lost signal less than half way on the way to waypoint 1. I thought it was when going back according to the mission settings.

This make things more complicated since in Litchi missions the drone becomes completely autonomous and since as long as the contact between the RC and the AC is not back, nothing can be done to change the programmed flight.
Considering this, your drone could disappear anywhere along the path from waypoint 1 --where your friends saw it-- to waypoint 3.
Had you inverted the order of waypoints (waypoint 1 close to your home/take-off-point and waypoint 3 at your friend's home), you could have controlled the mission till almost waypoint 2 making sure that you were flying well above trees and everyting tall. By programming in Litchi the "Finish action" as "Reverse", your AC would have flown back following the same track at the good altitude. Next time...!
Sorry but this is impossible to do more for retrieving yours drone with only these data :-(

 

[Paul Schulze]

I have a question about the Litchi app. The DJI GO app records flight data in that you can move along the flown path and get a readout of longitude and latitude at any point in the flight. I do not use Litchi very much but I was wondering if it has a record feature like the DJI Go app?

I Believe one could use the DJ I go app data to locate a downed drone using the latitude and longitude of the last point recorded. Correct me if I'm wrong on this.

 

[Peio64270]

I have a question about the Litchi app. The DJI GO app records flight data in that you can move along the flown path and get a readout of longitude and latitude at any point in the flight. I do not use Litchi very much but I was wondering if it has a record feature like the DJI Go app?

I Believe one could use the DJ I go app data to locate a downed drone using the latitude and longitude of the last point recorded. Correct me if I'm wrong on this.

Yes it has.
But this works as long as your app receives infos (downlink) from the drone.
In the case of our friend, here, this downlink was out well before the drone stopped flying in a Litchi mission.

 

[Paul Schulze]

If this happens, can one move toward them drone and pick up some data as you get within communication range of the drone? If this is so, what kind of conditions must exist for uploading the flight data? I assume the antennas and gimbal must be intact? Also, if you get close enough to the downed aircraft, will it report back what is wrong, e.g., it might not start because the gimbal is disconnected although the aircraft is turned on?

I assume you would have to do this before the battery goes dead. Therefore any action you might take in regard to this would have to be done right away after the crash.

 

[The Springs]

You said you ran the mission two hours earlier .How did you start that one ? How was it different ?

 

[The Springs]

I'm also thinking the path taken to get to WP1(since the AC is no going to WP2 on the way could have been slightly different than the mission path coming back .Meaning it could have just missed some obstacle on the way out but not on the way back ?

 

[Jim Roof]

Ok, I can't be total sure that it was Litchi but I installed it today and no longer have a Drone. I have flown successfully for 8 months using DJI go. No issues..

I installed Litchi and tested it out with a couple preprogrammed flights and all went well until the last one. I sent it up following a saved route that I had previously flown today but this time it never came back. It was a waypoint route and therefore was out of communication for a brief moment so I have no idea where it went..

Its so disappointing to see my 1400 dollar Drone just disappear. I'm speechless. Does anyone have any ideas? How does the DJI's find my Drone work? Can I have DJI lock the Drone so no one can use it and maybe it gets turned in for the the reward I offered in nextdoor. (Neighborhood chatboard )

It flew this saved route just 2 hours before in perfect weather and it had plenty of altitude so I have no idea what happened. Pic attached..

That area is about 3 miles south of me. Not sure if there is anything I could do to help, but I am willing. If it went down in the subdivision then you have to factor in the human element in addition to any failures of technology.

 

[abwRN]

You said you ran the mission two hours earlier .How did you start that one ? How was it different ?

The only real distance would be the altitude and setting the final waypoint correctly. The 2nd flight was modified because I wanted to get better detail on the ground. When I made the fatal error of leaving the final waypoint at 38 feet, I was doomed. What's really bad is that I noticed this error right after it went out of range and I knew I was doomed..

 

[abwRN]

That area is about 3 miles south of me. Not sure if there is anything I could do to help, but I am willing. If it went down in the subdivision then you have to factor in the human element in addition to any failures of technology.

Thanks but I think everything that can be done has been done..All businesses notified, Posted on Nextdoor, Alerted local shops, etc...Ground Search, Air Search Thanks for the offer though...

 

[sar104]

A little late with the observations but, based on your description of 184 ft AGL at WP2, descending to 38 ft AGL at WP3, I would say that it hit a tree in the vicinity of Lakeshore Dr NW. If you use that linear descent profile and the Google DEM to plot flight path AGL between WP2 and WP3, you get the following:

At 840 ft from WP3 it is only 65 ft AGL, and at 430 ft from WP3 it is down to 46 ft AGL. Google's street view suggests that the trees in that area are taller than those numbers.

Looking at the extruded flight path overlaid on Google Earth illustrates the locations:

 

[The Springs]

Wouldn't he have regained signal by then ?

 

[sar104]

Wouldn't he have regained signal by then ?

I would have expected the signal to be back but maybe not, with all the trees. The conclusion assumes that the flight didn't run into other, unknown problems, and hinges on the observation that the much greater altitudes AGL between WP1 and WP2 are more than adequate to clear all obstacles, as on the way out.

 

[The Springs]

I'm not sure how Pelio64270 worked out that WP2 is 47m (I will have to follow through his logic again ) but rough calculations brings the flight path much closer to the larger rise near the OPs friend's house about 25 m (82 feet) above the highest point .The AC would have missed this rise on the way out possibly due to the slight kink in the wp path where wp 2 is .( the AC flying essentially from wp3 to wp 1 direct)

I keep thinking that if he lost contact near wp 2 on the way out surely he would have regained contact some where near there on the way back ? Although I have noticed when you lose contact the AC has to be much closer coming back to you before you regain it sometimes.
Again just a theory that expands the search area rather than narrows it sorry .

 

[sar104]

I'm not sure how Pelio64270 worked out that WP2 is 47m (I will have to follow through his logic again ) but rough calculations brings the flight path much closer to the larger rise near the OPs friend's house about 25 m (82 feet) above the highest point .The AC would have missed this rise on the way out possibly due to the slight kink in the wp path where wp 2 is .( the AC flying essentially from wp3 to wp 1 direct)

I keep thinking that if he lost contact near wp 2 on the way out surely he would have regained contact some where near there on the way back ? Although I have noticed when you lose contact the AC has to be much closer coming back to you before you regain it sometimes.
Again just a theory that expands the search area rather than narrows it sorry .

I guess I'm not seeing that. If he was at 184 ft relative to takeoff point (WP3) for the outward flight and the return flight as far as WP2, then he should never have dropped below 120 ft AGL - much higher than the trees appear to be on the WP1 side of the flight.

 

[abwRN]

I'm not sure how Pelio64270 worked out that WP2 is 47m (I will have to follow through his logic again ) but rough calculations brings the flight path much closer to the larger rise near the OPs friend's house about 25 m (82 feet) above the highest point .The AC would have missed this rise on the way out possibly due to the slight kink in the wp path where wp 2 is .( the AC flying essentially from wp3 to wp 1 direct)

I keep thinking that if he lost contact near wp 2 on the way out surely he would have regained contact some where near there on the way back ? Although I have noticed when you lose contact the AC has to be much closer coming back to you before you regain it sometimes.
Again just a theory that expands the search area rather than narrows it sorry .

Wow, you guys are the bomb. All of this is sinking in and although it expands the area, it gives me hope..[emoji16] Waypoint 2 was 184 feet. The building in front of the pipe yard is where I lost contact headed out. That is before Waypoint 2. It's possible that because it was coming in lower on the return flight it never regained signal due to all the trees. As you can see, I live in Berkeley Lake and we have been a tree city for 18 years running. You can't even touch the tree without major red tape. It's also one of the reasons I have ordered a ground station with amplifiers that will be here next week. It's actually the very first one, I think you guys are gonna love it.

Anyway, I think we're onto something because I've searched everywhere with no luck. If it's possible that it went down closer to Lakeshore Drive by the pond that could be good. The people who live by the pond are older and wouldn't be checking our neighborhood forum. They are very nice and will definitely let me look around

 

[abwRN]

With this information, I will be able to fly my Mavic along the same path while checking the tree height in real time. I can confirm your information and then I will consider that a prime area to search.