Hi all!
So I've read a bunch of posts and have gotten most of the way through deconstructing my issue but I just can't get tell whats actually going wrong with the bird. I captured the latest occurrance on video with some scarry results and have pulled the flight data files.

In short, I keep getting 'No Signal' issues mid-flight. Everything is fine and then bam, red light comes on the RC and no video to the screen. I retain 'some' control over the bird but it yaws and rolls and wants to pull away and fly off, it's like it has lost all trim. It's been back to DJI who tested it, found nothing wrong, and sent it back. It is pure luck, and reluctance on my part to lose LOS, that its not just flown away (as RTH does NOT kick in!)

So... I'm asking for your help! What is happening to my bird? To save a few questions....

Phantom 3 Advanced
1.3.2
Experienced the issue with iPad Air and iPhone 6 running latest DJI Go.
Yes, I've used multiple cables and restated the GO app mid flight, doesnt reconnect (also red light is 'on' on the RC)
I'm not near any power cables.
I calibrate before every flight.
I did do a cold recalibrate after updating to 1.3.2 and re-pair the bird to rc.
Enable Hardware Decode - ON
No issues with finding GPS Lock

Firstly, look at the video. I've annoted it to what is actually happening and shortened the first 9 minutes of flight to a few seconds to get to the interesting bit. It really freaked me out when I watched it for the first time just how much it rolls about with no apparent stabilisation of the camera.



Next, the log from the iPhone 6 it was connected to. The data stops at 9:09 when the bird is 45m up but close to where I am stood (fortunately).


Now, from the .DAT file from the bird an extra loop to the south east to show where the bird actually went after the 9 minute mark (using https://www.mapsmadeeasy.com/log_viewer )




(Also, does anyone know why the date and time would be wrong on the .DAT file? The flight was 5th September not 26th August)


I also used djilogs.com which just gave me a comment log file.

https://dl.dropboxusercontent.co ... ogMessages.txt.html

If anyone is good enough with these logs that could tell me what happened to knock out the signal and make the bird behave so strangely it would be much appreciated!!

Or, if I need to put the logs through some other readers please just point me in the right direction.

Any help appreciated!

Many thanks

Rob

Wish I could help. My bird (P3P) did basically the same thing this past weekend. I've been very nervous about sending her up again. I updated to the new firmware as well... nothing changed for me. Also, the video image/signal has become extremely pixelated. I'm plannig to call tech support to see if they have any suggestions. [ not gettign my hopes up ]

Man i almost crapped my pants watching this, VERY creepy attitude considering you followed all the pre-flight check lists....

I know it would seem crazy coming from me BUT it looks like a GPS replay attack was being done against you, where one would know you are flying in that location and beams a strong GPS signal with wrong coordinates (hence the wrong date on the GPS log in the .dat file).

Below is one of the reported sources of the hack which i won't bore you with the details as it gets really tangled.

Source link

When you were trying to bring it back did you switch to ATTI mode or was still in gps ?

I have a hypothesis on what’s going on, but Not sure if I should say, as most people would think I have completely  lost my signal, but it could answer a lot of what’s going on. Read my little problem not so different from this, almost the same thing.

Alien tech Posted at 2015-9-8 13:11
I have a hypothesis on what’s going on, but Not sure if I should say, as most people would think I ...

What are your thoughts ? i won't judge.

Willie Wonka Posted at 2015-9-8 20:23
What are your thoughts ? i won't judge.

Ok, we have some high levels of geo- engineering over the last 2 days or so. Only last night, although clear skies, my security infrared cameras were picking massive amounts of reflective material, almost like a fog or mist in the cameras.   I think this could be the reason, we are finding problems finding and maintaining signals on the GPS side of things, its dispersing the signals all over the place.
Check the link out. information on geo-engineering  

For those who watch the skies and see this going on, monitor, when they carry out heavy spraying, and see what happens within 24 to 36 hours later, regards GPS locks or instability regards signal, on your P3
Be an interesting experiment to see if there is any correlation!   

Alien tech Posted at 2015-9-8 14:08
Ok, we have some high levels of geo- engineering over the last 2 days or so. Only last night, alth ...

Yeah now i know where you going with this, most will say you are out of your mind, but i know that this theory is in the works as a jamming technique by spraying particles that act like a reflector for radio  signals which cause mayhem, i hope to god that this is just an act of god not an act of man, as if this drops down to surface level it could cause lung damage.....

Thanks for the responses, however I'm not sure the geo-engineering or gps attack scenario fits...

I've had this issue occur over a period of weeks in numerous locations. Some only a few seconds into flight, some right at the end. Also, there was another P3A in the same airspace which remained unaffected. Also, I'm not sure if this would explain why I lost connection or why the bird stopped stabilising the camera to a level horizon.

Also, I was in P-GPS mode the whole time. You can see the mode in the screen pic from the flight log in the last second before connection was lost. The data in the DAT file was accurate to where the bird actually flew, so the GPS co-ords reordered were bang on.

Anyone from DJI care to chime in?

heybutch1 Posted at 2015-9-8 14:57
Thanks for the responses, however I'm not sure the geo-engineering or gps attack scenario fits...

I ...

In this case log a ticket for support to have them look at it better than us here speculating and going crazy and wasting your time.

Solar Kp index was measured above 5 in various areas on the 8th.  That's a possibility anyway.

The flight with the issue was on Saturday 5th September. I check the kp index for that day and it looked to be about 2 - 3. See data here...

http://services.swpc.noaa.gov/text/daily-geomagnetic-indices.txt

I'm really not buying the interference explanation for this NO SIGNAL issue. Does anyone know what to make of the comment log the djilogs.com spat out from the .DAT file?

https://dl.dropboxusercontent.co ... ogMessages.txt.html

heybutch1 Posted at 2015-9-8 21:57
Thanks for the responses, however I'm not sure the geo-engineering or gps attack scenario fits...

I ...

Ummm well I have thought about this, and my little idea is now not holding water, blown my own hypothesis out the water. I realized we use cable free internet connection, we connect via wireless to the local town which is about 4 miles form here, if there were anything in this, it would be screwing with that too, Not the case, so its a dead idea. having said this, these particulates do have alloys and copper sulfates in them along with barium and other toxic materials. But that's another issue.
I did try the craft later, in the house, and although I had the amber light showing poor GPS, it did connect and the camera was working. So, I assume if I had of been outside, everything would have been normal again. So, now its back to squire 1, I don't know, odd pooo going on, but I don't get it. It does dent your faith in going on with it on little adventures though! I think for while at least I will keep it within 2 or 300 meters in the event some other odd crap goes down again..  

Have you upgraded to the new 1.4 firmware?Interested to see if you still have the same issues after the update.

Alien tech Posted at 2015-9-8 20:08
Ok, we have some high levels of geo- engineering over the last 2 days or so. Only last night, alth ...

Chemtrails? Really?
You must be kidding!

There are thousand things that can go wrong and do go wrong all the time: software, hardware, radio connection, user error, etc.
But you pick not only a theory that is not likely, you pick one that is completely absurd and utterly crazy.
You are wasting your time and our time with this total nonsense.

Alien tech Posted at 2015-9-9 04:08
Ok, we have some high levels of geo- engineering over the last 2 days or so. Only last night, alth ...

love to see your vid of this...

TheDreamingWatc Posted at 2015-9-9 12:21
Chemtrails? Really?
You must be kidding!

No chem-trails on this occasion, read the post I backed off of it, ( I was brains storming)  I do try and be fair and up front.  But they do exist, everywhere today, they being Chem-trails/geo-engineering. watch it happening all the time. Incontrovertible evidence of that fact!   If you think its completey whacky, I am happy to supply a list of material, If you look at it that is, which will make you go very quiet about it, as Hooo crap how do I answer that lot, or you will say something like, OK point taken. If you act open and fair, I garrantee you will loose the bebate as in what I can provide to back it all up...

Anyway; back to everyday stuff, today the old bird is acting normal again, whew, less stress, So, off the wall things aside, I am lost, don't have a clue why it happened......   Beam me up!   

Ok, I never thought about this before.  But I am a land surveyor and I use survey grade GPS for surveying all the time.   One of the first things that happens when you turn on your GPS is it looks for an ephemeris and almanac.   If the date on the one you have in memory is within a certain number of days then it can use the one you currently have but..   If it over a certain age then it has to download another one.  That is why I think certain times the bird will warm up and get GPS Lock fast because it does not need to download it.  But other times you might have to wait a minute.  Maybe yours stuck using an old ephemeris, and it is trying to hover somewhere else based on the old ephemeris / almanac data.  complete almanac is transmitted by each satellite in 25 frames total (requiring 12.5 minutes).[size=11.1999998092651px]  The almanac serves several purposes. The first is to assist in the acquisition of satellites at power-up by allowing the receiver to generate a list of visible satellites based on stored position and time, while an ephemeris from each satellite is needed to compute position fixes using that satellite.  (Not from memory but from wiki haha).  Global Positioning System (GPS) navigation satellites transmit electronic ephemeris data consisting of health and exact location data. A GPS receiver can use the transmissions from multiple such satellites to calculate its own location using trilateration.  If you ephemeris is out of date the bird could have a hard time locating and maintaining lock on all satellites

Edit:  It was the almanac that takes so long to get.  If I have not used my survey GPS for a couple weeks and then take it out it can take up to 15 minutes before I can work with it because it has to regenerate the almanac.  So I would imagine the same would be for the P3 if it had not been used for a few days it could take longert to regenerate the almanac.  And this is what I was thinking could be a problem when I saw the date time stamps.   Also, did you check the date on your device to see if it is correct / time and zone etc?


Just another thought..

Alien tech Posted at 2015-9-9 12:33
No chem-trails on this occasion, read the post I backed off of it, ( I was brains storming)  I do t ...

Of course it's completley whacky

i have the same problems i just downgrade the update

I have held off updating to 1.4.0 just while I wait for any negative feedback. Think I'll do it this weekend and go see what happens.

As for this evening, I flew again and had the issue again! About 5 mins into the flight the picture went and the green light on the rc went red. The bird started to full away again but was closer this time so easier to get a handle on it. A bloody pain. Just can't trust the thing.

Anytime you see your aircraft begin flying in such a matter always put it in A-mode right away and fly it back and land it asap. This was obviously a compass or gps issue. Not saying this includes you, but there is a lot of pilots that do not know how to do a proper compass calibration.

You also never mentioned updating the R/C firmware when you went to 1.3.2.

It sounds like in both cases you may have had too many processes going on with the device used and they both went into a reboot process. At that point you lose the signal, gps control, ect.

Also you are looking at the wrong files for flight info. You need to use the .TXT file which you download from the device and then run them through the converter on djilog.com . Then use Excel to view the converted .CSV file.

1320frank@comca Posted at 2015-9-10 05:00
Anytime you see your aircraft begin flying in such a matter always put it in A-mode right away and f ...

The update to 1.3.2 from 1.2.6 went fine, no issues. But, I did have the issue on 1.2.6 also.

As for processes on the device (iPhone 6), I close any apps and reboot before the flight. The app doesn't reboot, or stop responding, it just loses signal along with the RC.

I have taken the .TXT files off the device and put through djilogs.com. Also, I've run the KML file through a mapper.
file:///Users/rob/Desktop/Scr


Links for the CSV files from djilogs are here. Doesn't mean anything to me!

https://dl.dropboxusercontent.co ... t.Comprehensive.csv
https://dl.dropboxusercontent.co ... %5D.txt.Flytrex.csv
https://dl.dropboxusercontent.co ... txt.GoogleEarth.kml

Any help in reading these appreciated.

heybutch1 Posted at 2015-9-12 13:17
The update to 1.3.2 from 1.2.6 went fine, no issues. But, I did have the issue on 1.2.6 also.

As  ...

I looked at your logs to see if I could help you figure it out, but is looks like the log covers the nine minutes of flight BEFORE you had problems.

You must be looking at the log stored on the device not the quad itself because it still has you at 45m altitude when it stops due to loss of signal.

You need to get the log off of the actual bird itself. All the good stuff is missing.
EDIT: I see that you say that in one of your posts. Sorry. If you can put up the CSV file for the aircraft log, I'll take another look.

suqsid.bobmail Posted at 2015-9-12 21:18
I looked at your logs to see if I could help you figure it out, but is looks like the log covers th ...

Hi

Many thanks for taking a look. I'm not sure what file it is you need.

I have taken the .DAT file off the bird and put it through djilogs. It gave me an option to download this text file....

https://dl.dropboxusercontent.co ... ogMessages.txt.html
.... but nothing else. Is this it?

Any help appreciated!

suqsid.bobmail Posted at 2015-9-12 21:18
I looked at your logs to see if I could help you figure it out, but is looks like the log covers th ...

Hi

Many thanks for taking a look. I'm not sure what file it is you need.

I have taken the .DAT file off the bird and put it through djilogs. It gave me an option to download this text file....

https://dl.dropboxusercontent.co ... ogMessages.txt.html

.... but nothing else. Is this it?

Any help appreciated!

suqsid.bobmail Posted at 2015-9-12 21:18
I looked at your logs to see if I could help you figure it out, but is looks like the log covers th ...

Hi

Many thanks for taking a look! I'm not sure which CSV file you need.

I took the .DAT file off the bird and put it through djilogs.com but it only gave me have a .txt file.

Please let me know if there is somewhere else I should be looking!

https://dl.dropboxusercontent.co ... ogMessages.txt.html

Hi

Is anyone able to help with this? I feel like we've almost got the point where we can see exactly what happened!

Any help with this last bit appreciated!

Thanks

Rob

Hey. So finally got this resolved. Actually in the end DJI were pretty good. Every time I tried to fly this Phantom I kept having the NO SIGNAL issue a few minutes into the flight so I had to do something, it just wasn't safe to fly.

I contacted DJI Support and said that under the 12 month warranty I would like them to take the unit back and repair / exchange it. They looked at the flight logs from the app where the signal was lost and agreed it was not out of range etc. I posted the unit to the Netherlands and within a week they had looked at it and issued a replacement unit which should be here tomorrow.

As for the old one they said... "The OFDM unit had a defect and there were cracks in the shell.".

I've no idea about the cracks, I certainly didn't see any nor have crashed or even bumped the unit. I believe the OFDM unit is something to do with signal processing.

Well, mystery solved, finally!