I was flying with strong interference so I constantly kept an eye on the signal strength and I expected the signal bars to turn red before anything happened.

Then suddenly I got the red status bar saying "Aircraft disconnected" but the weird thing is I still had the live view and the controller was still responsive. I could still turn the AC around normally. After 4-5 seconds, the bar went green again.

The flight log does not show any "Aircraft disconnected" messages. Looks like a bug in the DJI GO 4 app?

DJI GO 4: v4.0.7
AC/Controller Firmware: v01.03.0600

Huh. Well, video downlink and RC control are two different systems, so I guess you could have momentarily lost RC connectivity and regained it by the time you tried to turn it around? When you say the flight log didn't show any messages, did you look at the Warnings log in the Go 4 app's General Sewttings?

Ex Machina Posted at 2017-4-24 20:09
Huh. Well, video downlink and RC control are two different systems, so I guess you could have momentarily lost RC connectivity and regained it by the time you tried to turn it around? When you say the flight log didn't show any messages, did you look at the Warnings log in the Go 4 app's General Sewttings?

I tried both replaying the Flight Record and the All Warnings under General Settings. Couldn't find anything. It happened a few times and after the last one, I pressed the RTH button. The AC ascended to the RTH altitude while the app kept saying disconnected. When it turned green again the message at 09:10:47 (returning to Home Point) popped up immediately. There's nothing regarding the disconnections before that.

Mine will also show poor radio signal at start up but never have a problem flying except app will crash after flying for some time.

Maybe the disconnections were so brief that the app couldn't keep up and display the correct status? But it's still weird that there was nothing in the logs.

jameswan Posted at 2017-4-24 20:29
Mine will also show poor radio signal at start up but never have a problem flying except app will crash after flying for some time.

Mine has that problem from time to time too, especially if I'm using some of the intelligent flight modes, which I imagine require some heavy lifting by the app.

Forgot to mention I'm using Galaxy S7 Edge.

Iamz Posted at 2017-4-24 20:40
Forgot to mention I'm using Galaxy S7 Edge.

Mine crash while I'm flying in normal P mode. Am using LG V20. Had tried turning off auto rotation as suggested by some users but didn't work for me. Wonder if it's due to the android version.

I would not be surprised about a bug in the app. I know that the app crashes repeatedly for me when the signal is weak or there are disconnects. The RC seems to handle this fine, but the app does not like this. I also get a blinking video transmission icon. I have never seen that the icon goes back to normal.

I just wonder why the DJI Go 4 app is so unstable and weird sometimes while 3rd party apps are rock solid and do not show any of these issues. I thought all apps were based on the official SDK and the app developers just put their UI on it.

There seem to be more issues since the app included sound. Try turning off the sound in the app and see if you still have any app problems. It just might be that some phones can't handle the load of flight control, video and sound recording.

Jenee 2 Posted at 2017-4-24 21:57
There seem to be more issues since the app included sound. Try turning off the sound in the app and see if you still have any app problems. It just might be that some phones can't handle the load of flight control, video and sound recording.

I'll try that next time as I've never really done anything with the sound anyway.

Dronoob Posted at 2017-4-24 21:51
I would not be surprised about a bug in the app. I know that the app crashes repeatedly for me when the signal is weak or there are disconnects. The RC seems to handle this fine, but the app does not like this. I also get a blinking video transmission icon. I have never seen that the icon goes back to normal.

I just wonder why the DJI Go 4 app is so unstable and weird sometimes while 3rd party apps are rock solid and do not show any of these issues. I thought all apps were based on the official SDK and the app developers just put their UI on it.

I've bought Litchi but not really using it because I thought the official app would be safer. Maybe it's time to change.

Iamz Posted at 2017-4-24 20:27
I tried both replaying the Flight Record and the All Warnings under General Settings. Couldn't find anything. It happened a few times and after the last one, I pressed the RTH button. The AC ascended to the RTH altitude while the app kept saying disconnected. When it turned green again the message at 09:10:47 (returning to Home Point) popped up immediately. There's nothing regarding the disconnections before that.

There's also the log in the aircraft itself, which can be extracted with the DJI Assistant app. I'd open a support request to get DJI involved.

Maybe something was lost in translation.  Some warnings don't really fit the data, they're just the most convenient bucket to drop a flagged condition into.

IMHO,  communications errors  are not described unambiguously.  There are at least 3 comm signals to be concerned with:  (1) commands going to from RC to AC, (2) telemetry from AC to RC and (3) video stream from AC to RC.   Obviously (3) is of lesser importance.  So the question is;  what is the origin of the "Aircraft Disconnnected" warning (and other comm warnings).  Does it (they) come from the RC, from the AC (via telemetry) or a combination of sources.  This is where you need to compare the AC .DAT files with the RC / GO log.

Could you please use a screen recording app to make a short video of this issue?
I'll help to report this to our engineers.

DJI Mindy Posted at 2017-4-25 22:17
Could you please use a screen recording app to make a short video of this issue?
I'll help to report this to our engineers.

If I can reproduce it while recording the screen, I'll post it here.

Iamz Posted at 2017-4-26 06:46
If I can reproduce it while recording the screen, I'll post it here.

Thank you for your cooperation. Keep us posted.

DJI Mindy Posted at 2017-4-26 23:52
Thank you for your cooperation. Keep us posted.

Here's the video. It's at 1:05.

Probably a script kiddie with ghetto setup trying to bring her down.

This happens to me as well.

Iamz Posted at 2017-4-27 11:33
Here's the video. It's at 1:05.
https://www.youtube.com/watch?v=xC1JLCDatiI

Sorry for my late reply.
I have confirmed with our engineers, it's probably the RC issue.
I would suggest you to send it in for further evaluation.

DJI Mindy Posted at 2017-5-3 19:14
Sorry for my late reply.
I have confirmed with our engineers, it's probably the RC issue.
I would suggest you to send it in for further evaluation.

Thank you for the reply.

Can you tell us what the engineers think the issue is? Is there something wrong with the actual signal or the reported status is just incorrect?

Also, if the issue is with the RC, I should see the same thing with another iOS device?

The iOS device is simply relaying/displaying the information from the RC, so yes, I would say you should see exactly the same thing no matter what device is connected to the RC.

Iamz Posted at 2017-5-3 21:23
Thank you for the reply.

Can you tell us what the engineers think the issue is? Is there something wrong with the actual signal or the reported status is just incorrect?

Yes, you might see the same issue with other device.
Since we cannot locate the issue remotely, we suggest you to send it in for further evaluation.