Lost GPS signal

[MAvic_South_Oz]

I think this was your text below . . .

The Aussie Open Sky used by CASA shows that, out at Shellharbour beach area is outside the regional airport flight path restriction. People get confused with the multiple areas named Shellharbour I.e Shellharbour airport is based at Albion Park Rail on the Highway, Shellharbour Hospital with the heliport is actually at Mt Warrigal, also Shellharbour Village I believe is the original Shellharbour with its small harbour but now is being swallowed up with big developments and a Marina. The only restriction the OP is under where he was flying was to be aware of the Heliport at the Hospital, if a Copter around just bring Drone down safely.
It’s all a bit confusing sometimes which app to follow. I yet been restricted by DJIs app yet.
Maybe I will take a drive down to test this out with my Mavic Pro. With the current Covid lockdowns it would come under essential “educational” purposes ?

DJI Flysafe is really 'out to lunch' on these uncontrolled airports, putting restrictions on them is basically far outside CASA rules to fly thee areas.

Yes, the airport is well inland, and had seen a couple of names there for it, Illawarra airport, Shellharbour airport.
DJI shows the flight path over that bay / parkland, but CASA say ok to fly, just do the usual land asap if planes etc come by.

Choppers too obviously in the heli zones.

I've read a few have been restricted by the DJI geofencing at airports, if the OP went up to the max height they could, then they were limited to the DJI 60m alt in that area too.
If you go closer to the airport (maybe a boundary carpark), take the M1P out and set up, you might find you can't even start the motors.

Another previous thread post from a WA pilot, he couldn't operate (approach the DJI NFZ) near this uncontrolled airport.

 

[Jonathonmp]

Strong radio signal interference.
It doesn't interfere with GPS though (AFAIK).

I'm no expert on the science, but I know if we take a plain fluorescent tube up the hill and approach the HT powerlines up there, it will start to glow, and get very bright underneath them.
The strong magnetic field from the power flow lines up the argon, xenon, neon, or krypton, and mercury vapor in them.

It's why we shouldn't fly our drones too close to powerlines.

Homemade Tesla coil!!

 

[itismo]

This might be a silly question however, I thought I would just ask as I don't understand why this happened to me during my flight today......
I was flying about 45 meters altitude and had 17 satellite connections and a strong signal...
Then all of a sudden I lost all satellite connections and received a verbal warning that the return home function would not function with out satellite signal.....
I temporarily lost control of my drone ,all though I will admit i may have just lost the orientation of the craft and thus was not putting control correct inputs
I managed to get it to the ground and subsequent Flights I noted that the satellite signal was intermittent at best...
Drone also seemed to gain altitude slowly with no input from me. This continue to happen for about 15 minutes Before It regain altitude stability
After the flight , on the return home I noticed a mobile phone tower of a 1/2 a kilometre from my flight location would this have affected the GPS signal?
Unfortunately the flight data during this event is not very reliable as the tracking of the drone was obviously lost during the failure of GPS signal.

I would greatly appreciate anybody's advice

Sorry for reviving an old thread but the same happened to me exactly as described and I took @sar104 's advice and calibrated compass and additionally IMU also.

Indeed I took off from concrete floor with possible steel structures whatever and I also had the "Compass calibration required" warning but it was not the first time so I thought it wouldn't be an issue.

The question goes to @Martyray , did it happen to you again?

 

[Meta4]

Sorry for reviving an old thread but the same happened to me exactly as described and I took @sar104 's advice and calibrated compass and additionally IMU also.

Recalibrating your compass and IMU are unlikely to have "fixed" anything, since they aren't related to the GPS.
Posting your flight data will be necessary to find out what actually happened.
Go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record from your phone or tablet.
That will give you a detailed report of the flight.
Come back and post a link to the report it gives you.
Or .. just post the txt file.

Indeed I took off from concrete floor with possible steel structures whatever and I also had the "Compass calibration required" warning but it was not the first time so I thought it wouldn't be an issue.

Launching from a reinforced concrete surface is asking for trouble.
DJI's warning message is confusingly worded.
If you had a compass error message when you placed the drone on the concrete, that isn't asking you to recalibrate the compass (which is working perfectly).
It warning you of a potential problem with your launch point and recalibrating isn't going to make that go away.

 

[Martyray]

Sorry for reviving an old thread but the same happened to me exactly as described and I took @sar104 's advice and calibrated compass and additionally IMU also.

Indeed I took off from concrete floor with possible steel structures whatever and I also had the "Compass calibration required" warning but it was not the first time so I thought it wouldn't be an issue.

The question goes to @Martyray , did it happen to you again?

ive only been up for a few flights since this happened.
i recaled everything.
seems to be trouble free now....

 

[itismo]

Recalibrating your compass and IMU are unlikely to have "fixed" anything, since they aren't related to the GPS.
Posting your flight data will be necessary to find out what actually happened.
Go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record from your phone or tablet.
That will give you a detailed report of the flight.
Come back and post a link to the report it gives you.
Or .. just post the txt file.

Launching from a reinforced concrete surface is asking for trouble.
DJI's warning message is confusingly worded.
If you had a compass error message when you placed the drone on the concrete, that isn't asking you to recalibrate the compass (which is working perfectly).
It warning you of a potential problem with your launch point and recalibrating isn't going to make that go away.

Hello Meta4,

First, I would love to thank you for your useful contribution to this post and many other posts that I have read
Second, my flight logs are of no use, I was using litchi and forgot to put in an sdcard so no DAT file, the flight log itself does not show the whole flight path since there was no GPS shortly after take off.

I quote your update from another similar post
"The gyros in the IMU are initialised based on the incorrect compass reading.
After you launch and exit the magnetic field, if you turn the gryos disagree with the compass and you get your compass error.
That's followed by the drone dropping GPS and falling into atti mode and depending on the difference between the false compass reading and actual, the drone may zip away in an uncontrollable curved flight at high speed in the worst cases"

In my case in the CSV generated by litchi it shows 0 GPS sats shortly after take off as I actually could see that in the app, then the drone started drifting with the wind, after some minutes i could recognize where it is visually using on screen video and surprisingly the compass was still pointing to the correct direction at me so I lowered altitude and at this moment i regained satellites then brought it back home.

So drone dropped GPS, fell into ATTI mode but it did not zip away in any uncontrollable movements (I was near a NFZ so I am really happy it did not regain GPS at that point).

Here's the Litchi CSV I have

DJI Flight Log Viewer | Phantom Help

Upload and view DJI Phantom, Mavic, and Spark flight logs online

www.phantomhelp.com

 

[Meta4]

Hello Meta4,

First, I would love to thank you for your useful contribution to this post and many other posts that I have read
Second, my flight logs are of no use, I was using litchi and forgot to put in an sdcard so no DAT file, the flight log itself does not show the whole flight path since there was no GPS shortly after take off.

I quote your update from another similar post
"The gyros in the IMU are initialised based on the incorrect compass reading.
After you launch and exit the magnetic field, if you turn the gryos disagree with the compass and you get your compass error.
That's followed by the drone dropping GPS and falling into atti mode and depending on the difference between the false compass reading and actual, the drone may zip away in an uncontrollable curved flight at high speed in the worst cases"

In my case in the CSV generated by litchi it shows 0 GPS sats shortly after take off as I actually could see that in the app, then the drone started drifting with the wind, after some minutes i could recognize where it is visually using on screen video and surprisingly the compass was still pointing to the correct direction at me so I lowered altitude and at this moment i regained satellites then brought it back home.

So drone dropped GPS, fell into ATTI mode but it did not zip away in any uncontrollable movements (I was near a NFZ so I am really happy it did not regain GPS at that point).

Here's the Litchi CSV I have

DJI Flight Log Viewer | Phantom Help

Upload and view DJI Phantom, Mavic, and Spark flight logs online

www.phantomhelp.com

There's nothing in this flight data to suggest a yaw error incident or any compass issue at all.
You've had a mysterious problem with GPS reception.
The number of satellites gradually dropped and eventually reached zero which left the drone in Atti Mode, but still completely controllable.
The issue appears to be a hardware problem with your GPS receiver or perhaps a loose connection.