Phantom 4P lost GPS & flew away

[Chiuki]

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(Not mine, but my brother in Colorado) was flying last night above his backyard, high enough to see the wildfires smoke etc, when the GPS lock became unreliable going from 14 to zero. After about 10 minutes the drone drifted off in a NW direction towards Mt. Herman Rd, before autolanding at what it appears to have believed was the home point. Seems to have landed in a grassy place near some pines.
wind was pushing WNW 10mph

any Ideas on how to figure out where it may have landed, more or less?? Thanks for any suggestions. DAT file attached and some screen shots- one from the flight that shows (blue dot) where he was running as it was disappearing over the houses and trees to the NW of that street.

 

[Chiuki]

And for what it's worth, here is the Airdata record

 

[Chiuki]

Using time in the air, wind speed & direction, just found it - 100% ok, exactly where I calculated it should be.

 

[Lets Fly]

Using time in the air, wind speed & direction, just found it - 100% ok, exactly where I calculated it should be.

Was it on the roof?

 

[DanMan32]

Although I'm sure members on this forum would have been glad to help in this case, you may want to consider posting in PhantomPilots for Phantom related issues.

 

[itsneedtokno]

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(Not mine, but my brother in Colorado) was flying last night above his backyard, high enough to see the wildfires smoke etc, when the GPS lock became unreliable going from 14 to zero. After about 10 minutes the drone drifted off in a NW direction towards Mt. Herman Rd, before autolanding at what it appears to have believed was the home point. Seems to have landed in a grassy place near some pines.
wind was pushing WNW 10mph

any Ideas on how to figure out where it may have landed, more or less?? Thanks for any suggestions. DAT file attached and some screen shots- one from the flight that shows (blue dot) where he was running as it was disappearing over the houses and trees to the NW of that street.

I would still like to know why GPS failed.

Second time I've read about this recently, and haven't seen it before (maybe I missed it)

 

[Meta4]

before autolanding at what it appears to have believed was the home point. wind was pushing WNW 10mph

Without GPS, the drone has no way to steer toward the home point or anywhere else.
The drone started to autoland as it is programmed to, when it has no GPS and signal is lost.
This started just after 12:51.7
GPS failed at 7 seconds into the flight.
It would be interesting to hear how your brother found the drone as the data gives no clues.
He actively flew it for 12 minutes and doesn't appear to have made any attempt to bring it back.
Perhaps he was flying visually and knew the location.

I would still like to know why GPS failed.

It was quite likely to be a faulty GPS receiver or a very loose connection.

 

[itsneedtokno]

Without GPS, the drone has no way to steer toward the home point or anywhere else.
The drone started to autoland as it is programmed to, when it has no GPS and signal is lost.
This started just after 12:51.7
GPS failed at 7 seconds into the flight.
It would be interesting to hear how your brother found the drone as the data gives no clues.
He actively flew it for 12 minutes and doesn't appear to have made any attempt to bring it back.
Perhaps he was flying visually and knew the location.

It was quite likely to be a faulty GPS receiver or a very loose connection.

So 7 seconds after take off they lost GPS, and would have seen that on screen right?

That would have been a red flag to me.

They were flying ATTI the whole time?

 

[BudWalker]

Using time in the air, wind speed & direction, just found it - 100% ok, exactly where I calculated it should be.

I'm curious. Was the P4P found here

The .DAT continued recording and at about 1081 secs the connection was re-established. The location shown above is from the GPS receiver.

During the air born portion of the .DAT the number of sats kept dropping to 0 and GPS:VelN would become invalid. But, after the P4P had landed and motors stopped at about 939 secs these signals were solid. This suggests some kind of intermittent HW issue (possibly vibration induced?).

 

[Chiuki]

update - @BudWalker yes it was found in your red circle, about 3/4 from the center towards the red line at about the 2:30 position! Nicely pinpointed. let me attach a picture after i high five you for your excellent investigation skills! ?
David said the drone didn't respond to any stick control, but knowing him, he probably panicked, pulled back a few times (from what it looks like), did some random panicky stick movements..., and the drone was poinint towards him, causing it to fly further, then he was running after it, so thus, no further attempts to use the RC (i'm guessing based on his story, knowing him, and looking at the flight log. - - - as he watched it disappear behind the rows of houses and trees.
Got it back from DJI repair - sure enough, bad GPS module according to them. (who reallly knows for sure) They replaced it, but in the meantime, he bought a new MA2 (so as not to lose his real estate gig)
Sorry for the crap sentences, here's some pictures, but not Wonderwall. (the map i sent him as the most likely place to look - wasn't too far off, but Bud - you were way closer.)

 

[Chiuki]

Was it on the roof?

Nah, it was behind some farmer's house a ways off. Had to be quick, as the farmer's rumoured to be trigger-happy. (it's posted as such)

 

[Chiuki]

So 7 seconds after take off they lost GPS, and would have seen that on screen right?

That would have been a red flag to me.

They were flying ATTI the whole time?

yeah, that's probably right... but David was probably not paying attention. I think we all make some noob mistakes - his was less expensive than mine, thankfully

 

[Chiuki]

Without GPS, the drone has no way to steer toward the home point or anywhere else.
The drone started to autoland as it is programmed to, when it has no GPS and signal is lost.
This started just after 12:51.7
GPS failed at 7 seconds into the flight.
It would be interesting to hear how your brother found the drone as the data gives no clues.
He actively flew it for 12 minutes and doesn't appear to have made any attempt to bring it back.
Perhaps he was flying visually and knew the location.

It was quite likely to be a faulty GPS receiver or a very loose connection.

I posted an update about that, and DJI didn't say -why- the GPS failed. I will ask if David got any definitive answer about that. Would make me a bit hesitant to rely on a machine like that.

 

[itsneedtokno]

yeah, that's probably right... but David was probably not paying attention. I think we all make some noob mistakes - his was less expensive than mine, thankfully

Yeah, my MA1 is likely an artificial reef by now. ?

 

[Chiuki]

Yeah, my MA1 is likely an artificial reef by now. ?

My M2P also. In a busy cargo shipping canal into the port of Amsterdam. Maybe an archeologist will find it and retrieve my contact info from the SD card... hahaha, yeah right. Condolences on your loss. I feel your pain, i truly do.?

 

[itsneedtokno]

My M2P also. In a busy cargo shipping canal into the port of Amsterdam. Maybe an archeologist will find it and retrieve my contact info from the SSD hahaha, yeah right. Condolences on your loss. I feel your pain, i truly do.?

Circling a 75' "Viking" Convertible.

Did three manual orbits, well... 2 and a half lol.

My cached footage was all I had, but I lost that along the way too

 

[Chiuki]

Circling a 75' "Viking" Convertible.

Did three manual orbits, well... 2 and a half lol.

My cached footage was all I had, but I lost that along the way too

ouch. what caused the ultimate demise? (i had the video feed freeze with the bridge (and the sign on the side of it) about 1 foot from the camera at a weird 45 degree angle. hit the bottom edge (concrete) sideways (because i was a moron, and didn't check the height first) man, that was an expensive lesson in planning. d'oh!?‍

 

[itsneedtokno]

ouch. what caused the ultimate demise? (i had the video feed freeze with the bridge (and the sign on the side of it) about 1 foot from the camera at a weird 45 degree angle. hit the bottom edge (concrete) sideways (because i was a moron, and didn't check the height first) man, that was an expensive lesson in planning. d'oh!?‍

As I circled for the last time (the lowest pass) I clipped a channel marker. Literally the corner.
When I went to the marker to go diving, ? I saw a 1" square of chipped paint in the corner. I knew right away. ?

I tried to blame it on everything under the sun... It was me. I was to blame. ?

With my rescue jacket from @Phantomrain.org ... that will never happen again.?

Beyond the fact that I won't orbit that low anymore either. ?

In my cached video I could see the boat captain signaling me to gain elevation, but I couldn't see what he was doing while I was flying, only after review. ?