My Pro+ Never Returned Home After Losing Signal? Just disappeared

[Northern Canadian]

Location to airports and more.

 

[sar104]

Location to airports and more.

If you know that he did not contact the airport then possibly, but that information was not provided. In any case that would be a problem under FAA regulations - no need for local Nevada laws to address that. I assumed that you were referring specifically to the Nevada UAV trespass measures.

 

[ByronB]

As one alternative consider the possibility that the battery in the p4 disconnected and then fell out at the point of last signal. I do not know why this happens, maybe because of flexing of the craft. I always have had trouble removing the battery because it catches on the way out. Fortunately one day after flying about 2 min I made a sharp left about a 100 yards away and 100 feet high when I saw the battery fall out. I know what you are thinking "impossible" but I saw it. The p4 did not continue more than 20 more feet as it fell into the trees after the battery did. This was in the rainforest I was flying over, lower than the takeoff point on the top of a hill. If it was not for the green background of the forest I would not have seen the battery fall. After paying several native people to look for it for three hours they located the battery and then went back to finally discover the drone in a nearby tree. I do not know how it could fly at all if the battery was not securely in the drone at takeoff!!!

 

[Jerry H]

Hi all,

So I was wondering about what to expect and proceed after my drone incident this week. Weather was sunny, clear, with calm winds - approx 11:30 AM. It was a weekday in an empty area. I was flying north of the Las Vegas strip (near Circus Circus location to get a distant landscape capture of the buildings and surrounding mountains). About 12 minutes into the flight I was at the max distance reached at which, at this point, I was planning to fly it back home (top of a small empty parking garage) and end the flight. However, at that instant, it lost signal. This has happened many of times to me... at which point I've always select the RTH option. It usually takes a couple of seconds to retrieve signal again. However, this time, the signal never came back and neither did the drone. It continued flying further to a point that a hotel blocked it's view and I lost visual. I waited a bit, but the signal never returned. After a few minutes I sprinted the 1500 ft to it's last recorded location on the GPS map.
The drone was nowhere to be seen. I searched everywhere frantically but to my despair, it was nowhere to be seen. As each minute passed, the controller never picked up signal to the drone. I contacted that hotel's security and they also helped search their perimeter, including all their rooftops, etc... no one reported seeing it nor could they find it. I looked everywhere. Even knowing the phantom 4's ability to avoid obstacles, I searched to see if it possibly crashed somewhere. I then contacted the surrounding buildings and vicinity and no one saw it. I called air traffic control at the two surrounding airports to make a report about the drone and ask if they had picked it up on their radar or if any interference was performed. They unfortunately had no information. My partner stayed at the home location the entire time and never saw it come back nor reported back any further visual of it. We searched through the entire evening but it was never seen nor spotted by anyone. I left my number and made craigslist lost and found posts to no avail. I do not understand how this could have happened... we had our flight back home that evening and live nowhere near Las Vegas. I followed all of DJI's instructions sending them all my flight logs and the entire report. The lady on the phone informed me that depending on the investigation, they may send me a new one. Has anyone ever experienced such an incident? I used to fly the phantom 2 but never experienced something like this. Do you think DJI will be able to locate the drone? My memory card and footage is still there and it's such a mystery that on a clear day like that, the drone could just disappear. It even shows on the flight log at 280 ft, the drone just disappears off the screen.

I attached the flight record here: Airdata UAV - Flight Data Analysis for Drones

The text file is in an attachment.

Thanks - this means so much for me. I'd spent years saving since my phantom 2 and had the 4 since July. This has caused me so much anxiety. A few locals reached out to me and even said they'd try to fly their Mavics to try and find it.

I don' have answers for you but do have a question. I have a phantom 3 standard. About 3 months old. Recently it started losing signal at about 300 feet high, 1500 feet away. Dji had me relink remote to the drone. No help. Anyone else have this problem? ( no sign of damage to the antenna.

 

[sar104]

As one alternative consider the possibility that the battery in the p4 disconnected and then fell out at the point of last signal. I do not know why this happens, maybe because of flexing of the craft. I always have had trouble removing the battery because it catches on the way out. Fortunately one day after flying about 2 min I made a sharp left about a 100 yards away and 100 feet high when I saw the battery fall out. I know what you are thinking "impossible" but I saw it. The p4 did not continue more than 20 more feet as it fell into the trees after the battery did. This was in the rainforest I was flying over, lower than the takeoff point on the top of a hill. If it was not for the green background of the forest I would not have seen the battery fall. After paying several native people to look for it for three hours they located the battery and then went back to finally discover the drone in a nearby tree. I do not know how it could fly at all if the battery was not securely in the drone at takeoff!!!

That's certainly possible but it's not necessary to explain the disconnect, which occured precisely at the point where the aircraft flew behind a large building that would have blocked the signal. So the disconnect is not the puzzle here - it's the question of why the aircraft didn't reconnect when the OP changed position, return home on its own, or autoland in that vicinity if it could not make it past the building to go home. The high(ish) wind speeds aloft appear to be the most likely explanation.

 

[Bakersfield Quad]

That's certainly possible but it's not necessary to explain the disconnect, which occured precisely at the point where the aircraft flew behind a large building that would have blocked the signal. So the disconnect is not the puzzle here - it's the question of why the aircraft didn't reconnect when the OP changed position, return home on its own, or autoland in that vicinity if it could not make it past the building to go home. The high(ish) wind speeds aloft appear to be the most likely explanation.

I agree and though the OP did get to the scene quickly, it is very possible that someone saw it and picked it up before he got there. If the drone was not marked with his contact info, they would not know who to contact. Plus, someone could just decide, cool, found a drone!

 

[flyhelp]

That's certainly possible but it's not necessary to explain the disconnect, which occured precisely at the point where the aircraft flew behind a large building that would have blocked the signal. So the disconnect is not the puzzle here - it's the question of why the aircraft didn't reconnect when the OP changed position, return home on its own, or autoland in that vicinity if it could not make it past the building to go home. The high(ish) wind speeds aloft appear to be the most likely explanation.

Yes that's my biggest question. DJI responded to me yesterday letting me know that because the building caused the interference it's not a malfunction that the drone did not RTH. I am aware and agree with that. However they also did indicate the drone should've landed in that area - and that's my biggest question. I sprinted there as quick as possible to the drone's last reported location much before it shouldve landed due to battery issue.... I came with a few more minutes to spare. There just never was re-connection to signal despite going around the entire perimeter of the building. No witnesses... if it had landed there, someone from the Hilton for sure would have seen or reported it. Security had no knowledge of it, and tried their best searching all the rooftops. I even contacted back air controllers again to both airports post-flight if they had picked anything up. Literally the end-result has been as if the AC vanished in thin air. It's more-so I just want an answer as to where it's physical presence currently resides cause something doesn't seem to click? That area is surrounded by large concrete "fields" for carnival setups and was empty as of last Monday. And also being a med student having worked like crazy for the pro+, I was darn well searching like crazy for hours and going beyond every means to find it haha! I can't afford another one - and we no longer have time off to do research. So I'm starting to feel hopeless at this point since it's my biggest hobby - I used to have the phantom 2.
I've posted in multiple lost and found pages to no avail and it's hard since I live on the opposite end of the country from Las Vegas. Well, my next steps is that DJI gave me an opportunity to respond to hear my input, and I pretty much shared exactly that point - that the drone never reconnected with me changing my position, nor was it spotted, nor found in the demarcated area they told me it should be in. I doubt DJI will do anything about this. And no one's brought up to me that they'd found it.... the Hilton security has my number too, so had it landed where it was supposed to, I'm sure after a week has gone by, someone on their property have found it (it's pretty large). Yeah, I miss my memory card and footage, and someone from Dalton, Illinois named "Nick Slaughter" (phone: 615-554-7171) claims he has my drone and wanted me to wire him $325. I almost did but when I asked him for a picture of it, he turned on me that I dont trust him and spent an hour bashing me despite me being polite and never raising my voice. Everyone's told me he was a scam and I reported him to his local police department. Idk this has been such a headache... there'd been that wave of hope, but it's slowly falling back into hopelessness. I wish for none of you to ever have to deal with something like this. I'll let you all know what DJI responds - they probably won't see my email till after the weekend.

 

[sar104]

Yes that's my biggest question. DJI responded to me yesterday letting me know that because the building caused the interference it's not a malfunction that the drone did not RTH. I am aware and agree with that. However they also did indicate the drone should've landed in that area - and that's my biggest question. I sprinted there as quick as possible to the drone's last reported location much before it shouldve landed due to battery issue.... I came with a few more minutes to spare. There just never was re-connection to signal despite going around the entire perimeter of the building. No witnesses... if it had landed there, someone from the Hilton for sure would have seen or reported it. Security had no knowledge of it, and tried their best searching all the rooftops. I even contacted back air controllers again to both airports post-flight if they had picked anything up. Literally the end-result has been as if the AC vanished in thin air. It's more-so I just want an answer as to where it's physical presence currently resides cause something doesn't seem to click? That area is surrounded by large concrete "fields" for carnival setups and was empty as of last Monday. And also being a med student having worked like crazy for the pro+, I was darn well searching like crazy for hours and going beyond every means to find it haha! I can't afford another one - and we no longer have time off to do research. So I'm starting to feel hopeless at this point since it's my biggest hobby - I used to have the phantom 2.
I've posted in multiple lost and found pages to no avail and it's hard since I live on the opposite end of the country from Las Vegas. Well, my next steps is that DJI gave me an opportunity to respond to hear my input, and I pretty much shared exactly that point - that the drone never reconnected with me changing my position, nor was it spotted, nor found in the demarcated area they told me it should be in. I doubt DJI will do anything about this. And no one's brought up to me that they'd found it.... the Hilton security has my number too, so had it landed where it was supposed to, I'm sure after a week has gone by, someone on their property have found it (it's pretty large). Yeah, I miss my memory card and footage, and someone from Dalton, Illinois named "Nick Slaughter" (phone: 615-554-7171) claims he has my drone and wanted me to wire him $325. I almost did but when I asked him for a picture of it, he turned on me that I dont trust him and spent an hour bashing me despite me being polite and never raising my voice. Everyone's told me he was a scam and I reported him to his local police department. Idk this has been such a headache... there'd been that wave of hope, but it's slowly falling back into hopelessness. I wish for none of you to ever have to deal with something like this. I'll let you all know what DJI responds - they probably won't see my email till after the weekend.

From the time of the disconnect, how long would you estimate it took you to get around the far end of the taller Hilton tower - i.e. pretty much to the location where the obvious hypothesis would say it should have autolanded if it was unable to RTH? In a straight line that was around 0.3 miles. Did you go around the north side of the building to get there?

 

[sar104]

I agree and though the OP did get to the scene quickly, it is very possible that someone saw it and picked it up before he got there. If the drone was not marked with his contact info, they would not know who to contact. Plus, someone could just decide, cool, found a drone!

Yes - but it should not have autolanded for some time - it had plenty of battery left.

 

[flyhelp]

From the time of the disconnect, how long would you estimate it took you to get around the far end of the taller Hilton tower - i.e. pretty much to the location where the obvious hypothesis would say it should have autolanded if it was unable to RTH? In a straight line that was around 0.3 miles. Did you go around the north side of the building to get there?

It was about 30-45 seconds when my gut feeling kicked with the AC was not reconnected. I ran straight there. I tried following a straight path as much as I could - there were a few obstacles and I had to hop over a fence to get from one parking area to another to save time. Total was about 3-4 minutes max plus the 30-45 seconds. I first came from the southside first passing the small building and did a loop around the tall building along the south and north sides of the tall one where the drone would've been marked to be. I spent an hour there looking frantically with the control on sweeping the entire location. Eventually I went up the parking garage to look down from above to see if the drone had landed on anything. That's how I first met security, but explained the situation, and they tried helping out throughout the rest of the day.

 

[zlot]

You have my sympathy.
So while we're on the subject:
A LESSON TO ALL
Magic marker is wonderful stuff:
"IF LOST OR CRASHED AND FOUND PLEASE CALL XXX-XXX-XXXX" written on your drone may not look very pretty, but could be invaluable in these circumstances.

 

[CharlieU]

Here's what your flight data looks like: DJI Flight Log Viewer - PhantomHelp.com
You were flying at 281 feet when you flew the Phantom behind the Hilton Grand, which by my guess is about 360 feet high.
Your Phantom would have continued for a couple of seconds from the last point where you had signal.
Your RTH height was 98 feet so the Phantom would have attempted to RTH 3 seconds after losing signal at the height it was at already.
The likely outcome of this should be obvious.
The Phantom almost certainly flew into the Hilton in the vicinity of the white X or perhaps on the end of the building to the north of the X.

If you fly behind a tall obstacle, you will lose signal and pressing the RTH button will have no effect.
Your Phantom will attempt to RTH at whatever height you have set (or the height it is at if higher).
If that height is lower than the obstacle, the Phantom will probably fly into the obstacle.

Doesn't obstacle avoidance work with RTH and prevent a Panntom 4 Pro from crashing into a building? My P4 lost signal and was trapped behind a very large object. The battery eventually drained to 10% which forced a landing. Lost signal was set to Return Home. I luckily recovered the P4.

 

[Meta4]

Doesn't obstacle avoidance work with RTH and prevent a Panntom 4 Pro from crashing into a building?

In good conditions, it can but obstacle avoidance isn't magic and won't work all the time, anywhere.
Here are some of the limitations that can give it trouble:

As it was broad daylight, there's a good chance that obstacle avoidance prevented crashing and strong wind may be what prevented RTH or safe autoland from happening.

 

[KongWerks]

Hope you get banned off this forum for saying that

If I get banned for not feeling bad for someone who flies over the Strip, out of LOS... etc. I'm okay with that

 

[Bakersfield Quad]

I still think it just either landed and someone grabbed it or it tried to fly home, but did not make it and it is somewhere between. But, I am not so certain about the hovering in place until the battery hits 10% and initiates an emergency landing. There are other possibilities. If I understand it right, the drone can back track slightly, but will normally make a bee line to the home position. But I am not sure with those GPS mismatches that popped up, whether it really knew where it was. Could be that it was lost. If you haven't found it by now, I don't think it will show up.

 

[sar104]

I still think it just either landed and someone grabbed it or it tried to fly home, but did not make it and it is somewhere between. But, I am not so certain about the hovering in place until the battery hits 10% and initiates an emergency landing. There are other possibilities. If I understand it right, the drone can back track slightly, but will normally make a bee line to the home position. But I am not sure with those GPS mismatches that popped up, whether it really knew where it was. Could be that it was lost. If you haven't found it by now, I don't think it will show up.

I don't think the GPS mismatch messages are important. The flight track was very consistent at the end of the flight. It's a puzzle, but my best guess is that it got caught in the wind - with a north wind of 20 mph or so there could have been a significant wind speed between those buildings. At the end of the recorded flight it was facing 220° and moving at 15 mph on 160° with -3° pitch and 3° roll and those values were increasing - in other words it was braking against a NW wind to maintain that speed. I suspect that it blew further to the south and behind the other buildings before the OP arrived on scene, then was unable to make it back and autolanded.

 

[Bakersfield Quad]

I don't think the GPS mismatch messages are important. The flight track was very consistent at the end of the flight. It's a puzzle, but my best guess is that it got caught in the wind - with a north wind of 20 mph or so there could have been a significant wind speed between those buildings. At the end of the recorded flight it was facing 220° and moving at 15 mph on 160° with -3° pitch and 3° roll and those values were increasing - in other words it was braking against a NW wind to maintain that speed. I suspect that it blew further to the south and behind the other buildings before the OP arrived on scene, then was unable to make it back and autolanded.

Yeah, sounds plausible, it would have been overcome by the wind speed perhaps, then blown away from where it was. High winds can play havoc with you.

 

[Jthomp]

I lost control of a P3S (night flight, clear visibility, 100' max altitude [high enough to clear all the trees in the neighborhood] wind out of the east at around 20 - 25 mph, ATTI mode, GPS holding the drone in position about 200 fee north of take-off point).

Had a momentary loss of GPS lock - enough to kick out of ATTI - at which time the drone flew westward (because of the wind). I lost visual on the drone, and lost radio control as well. I initiated RTH but to no avail.

The drone passed just south of a solid tower portion of a 3-story building (which was a city block away - and which I never intended to go near on this flight) and a person nearby saw it "hook" around toward the northeast and crash into that tower feature and onto the roof below. I recovered the damaged drone the next morning.

It appears to me that the drone was pushed westward by the high wind. When it got in the vicinity of the tower feature of the building it encountered wind turbulence caused by the tower structure itself. That turbulence resulted in a zone of air pressure on the lee side of the tower that was lower than the air pressure on the windward side, thus creating a bit of a vacuum. The drone, still running a full power, moved into that low pressure area in an effort to get back to the launch point [GPS had been re-established by this time [but not radio control of the drone]] but the tower structure was between the drone and the launch point - hence the crash.

Lesson(s) learned:
1. Never fly in 20 - 25 MPH winds!
2. Be VERY aware of GPS signal loss messages flashing on your video device. ( I missed seeing 2)
3. Plan for the unexpected! VLOS means VLOS 100% of the time. It only takes 2 seconds for your drone to "Omigosh! Disappear!"
4. When searching for your lost drone be respectful to people, to their property, and, above all, to their time. Most people "out there" do not have a high opinion of "those blankety-blank drones" in the first place, and most are not employed to climb up on roofs to retrieve those "blankety-blank toys".