Spark disconnected without reason

ChristoffB · Jan 21, 2019

Hi all,

A few weeks ago I flew my spark at a river-mouth. Did some Quickshots, took some photos and recorded some videos - all without any issues. I was walking close to the drone whilst recording a video and flew over the river (for the second time during that flight, first time without issues), less then 10m from myself, and all of a sudden the app just says 'Disconnected' at the top, the video feed goes black and white and the drone goes into Atti mode and hovers in place. I have no control of the drone whatsoever. Fortunately the drone goes into RTH and starts heading back my way. Only when it was above me the RC reconnected and I was able to regain control.

I use an OTG cable connected to my Huawei P20 lite and I am using a 2.4GHz channel. There was nothing close-by that could have interfered with the signal.

The flight record shows nothing, accept for a sudden jump between the point where it lost connection and where I regained control (whilst in RTH mode).

Something odd I did notice:- Just before I regained connection, my phone acted as though I have just plugged in the OTG cable (there is a pop-up asking if I want to transfer files or charge only).

I have to add that it was quite a hot day and I was standing in direct sunlight with the RC. Not sure if overheating of either the drone or the RC could have caused this?

I have had a number of successful flights since.

Any input would be appreciated as I would not like for this to happen again!

jmbsmt63 · Jan 21, 2019

Get a different OTG cable and/or check/clean the USB ports on the controller and the phone. It is VERY easy to bend or displace those tiny connections and the port on the phone can gather a lot of "pocket lint".

Mark M · Jan 21, 2019

I am not confident using OTG for this reason. I bought a pair of Amazon OTG cables a while back. Both have given me severe anxiety. Both have disconnected mid-flight. Thankfully in both cases using the remotes RTH feature I was able to bring Sparky back to poppa.

For me, wifi has always been rock solid stable.

ChristoffB · Jan 21, 2019

" Both have given me severe anxiety..."

Am I correct in saying that on android one can only utilize the 5.8GHz spectrum when you connect your phone to the RC via wi-fi? To date I have not been able to connect to the remote's wifi from my phone when I choose a channel on the 2.4GHz spectrum. This is the reason I am using the OTG cable. The spark's range is dramatically increased when using 2.4GHz.

Paul215 · Jan 21, 2019

ChristoffB said:
" Both have given me severe anxiety..."

Am I correct in saying that on android one can only utilize the 5.8GHz spectrum when you connect your phone to the RC via wi-fi? To date I have not been able to connect to the remote's wifi from my phone when I choose a channel on the 2.4GHz spectrum. This is the reason I am using the OTG cable. The spark's range is dramatically increased when using 2.4GHz.

When you choose 2,4 GHz, it's the connection between Remote and Spark. 5,8 Ghz is the spectrum which androids can't work with. Same reason for me to use OTG.

ChristoffB · Jan 21, 2019

Paul215 said:
When you choose 2,4 GHz, it's the connection between Remote and Spark. 5,8 Ghz is the spectrum which androids can't work with. Same reason for me to use OTG.

I've read somewhere that when you connect the RC with the spark using 2.4GHz then you cant connect your android to the RC via the same spectrum. You will therefor have to connect your android via 5.8GHz which, as you say, won't work with android. This is also what you are saying, right?

Paul215 · Jan 21, 2019

Yep only one connection per spectrum. There is only one possibility for androids when you don't want 5,8Ghz for the Spark connection: Otg-cabel.

Barbara · Jan 21, 2019

ChristoffB said:
Hi all,

A few weeks ago I flew my spark at a river-mouth. Did some Quickshots, took some photos and recorded some videos - all without any issues. I was walking close to the drone whilst recording a video and flew over the river (for the second time during that flight, first time without issues), less then 10m from myself, and all of a sudden the app just says 'Disconnected' at the top, the video feed goes black and white and the drone goes into Atti mode and hovers in place. I have no control of the drone whatsoever. Fortunately the drone goes into RTH and starts heading back my way. Only when it was above me the RC reconnected and I was able to regain control.

I use an OTG cable connected to my Huawei P20 lite and I am using a 2.4GHz channel. There was nothing close-by that could have interfered with the signal.

The flight record shows nothing, accept for a sudden jump between the point where it lost connection and where I regained control (whilst in RTH mode).

Something odd I did notice:- Just before I regained connection, my phone acted as though I have just plugged in the OTG cable (there is a pop-up asking if I want to transfer files or charge only).

I have to add that it was quite a hot day and I was standing in direct sunlight with the RC. Not sure if overheating of either the drone or the RC could have caused this?

I have had a number of successful flights since.

Any input would be appreciated as I would not like for this to happen again!

I don't believe this is a problem with the OTG cable. If you lost complete control of the aircraft, ie. it did not respond to commands from the remote control, then the failure was with the connection between the remote and the aircraft. A failure of the OTG cable or connection would affect the DJI GO 4 app, but the remote control should continue to operate normally.

aidenholdingphotography · Jan 21, 2019

Maybe you were pointing the remote down or blocking the antennas.

ChristoffB said:
Hi all,

A few weeks ago I flew my spark at a river-mouth. Did some Quickshots, took some photos and recorded some videos - all without any issues. I was walking close to the drone whilst recording a video and flew over the river (for the second time during that flight, first time without issues), less then 10m from myself, and all of a sudden the app just says 'Disconnected' at the top, the video feed goes black and white and the drone goes into Atti mode and hovers in place. I have no control of the drone whatsoever. Fortunately the drone goes into RTH and starts heading back my way. Only when it was above me the RC reconnected and I was able to regain control.

I use an OTG cable connected to my Huawei P20 lite and I am using a 2.4GHz channel. There was nothing close-by that could have interfered with the signal.

The flight record shows nothing, accept for a sudden jump between the point where it lost connection and where I regained control (whilst in RTH mode).

Something odd I did notice:- Just before I regained connection, my phone acted as though I have just plugged in the OTG cable (there is a pop-up asking if I want to transfer files or charge only).

I have to add that it was quite a hot day and I was standing in direct sunlight with the RC. Not sure if overheating of either the drone or the RC could have caused this?

I have had a number of successful flights since.

Any input would be appreciated as I would not like for this to happen again!

nilanjan118 · Jan 22, 2019

Barbara said:
I don't believe this is a problem with the OTG cable. If you lost complete control of the aircraft, ie. it did not respond to commands from the remote control, then the failure was with the connection between the remote and the aircraft. A failure of the OTG cable or connection would affect the DJI GO 4 app, but the remote control should continue to operate normally.

I agree with this comment. One thing people always forget is that the connection between RC and aircraft has nothing to do with OTG. So even if the OTG cable unplugs by accident, you can plug it back in and the connection establishes within seconds. I have actually tested this with the drone hovering at a safe altitude. Unplug the OTG and the Go4 app screen turns grey. The connection between drone and RC is not affected and you can still control it with the joysticks. Plug it back in and screen comes back into life within a second.

lonchpad · Jan 22, 2019

I agree,
The OTG cable is not the problem, it it were to have a momentary disconnection it would come back or reconnect very quickly and not affect the connection between the controller and the Drone.
I speak from experience here.
The problem is interference of the RF signal between the controller and the drone. I read where Bluetooth from your phone could interfere and that makes sense because it does transmit a signal.
I lost my first Spark due to RF interference, was a sad moment for sure. There are many RF singnals in the airways that we don’t don’t know about because we cant see them. This and a DJI software issue that needs to be addressed is the culprit. I was flying along in Guam, very close to me and whammo! Disconnected! The home point apparently reset as i was taking off and it was right over the water (Sea) a few feet from shore. I tried to grab it but missed and it went in the salt water from the splash of me going in after it. Of course I did not think to set my phone and controller on the rocks before i went in after it, all got wet, luckily my new IPhone is waterproof, it still works today, not the controller though and scraped my leg on the underwater boulders pretty good as well.

This forum design sucks. It won’t let me upload a mp4 or ACI vid file to show you the fatale plunge.

Spark 317 · Jan 22, 2019

lonchpad said:
This forum design sucks. It won’t let me upload a mp4 or ACI vid file to show you the fatale plunge.

Create a YouTube or similar channel, upload your content there, and then post a link back to the Forum for us to see.

ChristoffB · Jan 22, 2019

lonchpad said:
I agree,
The OTG cable is not the problem, it it were to have a momentary disconnection it would come back or reconnect very quickly and not affect the connection between the controller and the Drone.
I speak from experience here.
The problem is interference of the RF signal between the controller and the drone. I read where Bluetooth from your phone could interfere and that makes sense because it does transmit a signal.
I lost my first Spark due to RF interference, was a sad moment for sure. There are many RF singnals in the airways that we don’t don’t know about because we cant see them. This and a DJI software issue that needs to be addressed is the culprit. I was flying along in Guam, very close to me and whammo! Disconnected! The home point apparently reset as i was taking off and it was right over the water (Sea) a few feet from shore. I tried to grab it but missed and it went in the salt water from the splash of me going in after it. Of course I did not think to set my phone and controller on the rocks before i went in after it, all got wet, luckily my new IPhone is waterproof, it still works today, not the controller though and scraped my leg on the underwater boulders pretty good as well.

This forum design sucks. It won’t let me upload a mp4 or ACI vid file to show you the fatale plunge.

Now that you mention the RF interference... I THINK I did not have my phone in airplane mode during that specific flight... Wifi and bluetooth would have been turned on, but not connected to anything. Maybe that caused the disconnection. Is just hope it never happens again!