No Signal Error???

James474474 · Aug 6, 2018

Had my mavic air for a week and loving it so far; gradually getting braver with it! I was filming my son on his bike to practise my flying skills and try to make smoother turns. I had followed him along the track he was riding before climbing to have a look around. The mavic was 239m from me and 456m from the home point at an altitude of 53m. Noticing the forth road bridge on the horizon I thought I would try a HDR photo while I was waiting my for son to ride back. As I went through the menus and selected HDR it appeared to lose signal. Within a few seconds it triggered the return to home which functioned perfectly.

The actions I took:
Confirm return to home on loss of signal.
Did not cancel return to home when I realised I still had control of it!
Moved it approx 2m to a better landing spot after sprinting 200m back to the home spot!

Questions:
1. Did I do the right thing in allowing it to return to home?
2. It went into auto land, I thought it would just hover?
3. Any idea what caused the issue?
4. Should I have done anything else/differently?

Video of my Galaxy S7 Edge screen showing the complete flight from just before loss of signal:

TIA,

James

Mossiback · Aug 6, 2018

James474474 said:
...Questions:
1. Did I do the right thing in allowing it to return to home?
2. It went into auto land, I thought it would just hover?
3. Any idea what caused the issue?
4. Should I have done anything else/differently?...

When it lost connection to the RC, you had no choice but to let it return home. At that point you hope that you set RTH up correctly and that it works.
If you set RTH to hover then it will. You would do this if you were flying under an obstruction (trees, etc). If it is set to return then it will return and land.
It momentarily lost connection with the RC. It could have been caused by a number of things like WiFi interference, distance, antenna position, environment, etc.
You mentioned that you still had control of it so I am guessing that the RC re-established a connection. If so, you could have cancelled RTH and continued to fly.

If anything, this should give you some degree of comfort knowing that RTH does work and brought your MA home.

Q24H · Aug 6, 2018

I'm new to the Mavic Air as well, curious about the message on top which showed "no signal" with frozen/static view for over 2.5 minutes from the point of signal loss to RTH landed, is that normal? Altho I can see the telemetry and map updating on the bottom, shouldn't the video feed also came back once the quad is closer to the operator? That part seems really strange to me no matter what he had on RTH confirmation screens

Mossiback · Aug 6, 2018

My apologies to the OP. I based my comments on the description rather than the video. I have seen so many videos showing screwed up video feeds that I did not want to watch another.

I had not seen the "Image transmission lost, Return to home now" message before. It must be on a newer version of Go 4 than I have. A Go 4 update caused so much pixelation for me just feet away from my MP that I had to downgrade. Video feed has always been a problem with Go 4 so I guess DJI decided to just add a RTH option instead of fixing the problem.

Had this happened to me I would have cancelled RTH and flown it back manually, but I am a bit of a control freak.

James474474 · Aug 7, 2018

Having watched the video again it doesn't look like controller signal was lost at any point, instead it just looks like the video feed was lost and for some reason the feed never returned until the MA was restarted.

Should I have tried restarting the dji go app during the rth or would that be considered high risk?

k9dave · Aug 7, 2018

Any particular reason you are using 5.8 ghz? You should get better distance with 2.4 ghz if you are not in a built up area.

James474474 · Aug 7, 2018

k9dave said:
Any particular reason you are using 5.8 ghz? You should get better distance with 2.4 ghz if you are not in a built up area.

Was going to try that next time. Assuming it defaulted to 5.8 on start-up?

InvisibleName · Aug 7, 2018

James474474 said:
Was going to try that next time. Assuming it defaulted to 5.8 on start-up?

Nope. When it's in auto mode, it will chose the frequency band it thinks is best for the signal environment it's started up in

Jibz · Aug 7, 2018

I have had the same issue at least 4 times recently. Most of the times, it occurs when I switch the flight mode, for example when I select tripod mode. The video signal freeze and goes black & white, but I still have RC control. So I usually get the drone back, land, and restart both the drone and DJI Go.

It is a bit annoying!

Mossiback · Aug 7, 2018

James474474 said:
...Should I have tried restarting the dji go app during the rth or would that be considered high risk?

Since you still had telemetry and a map, I would not restart Go 4 until I could see the Air.

James474474 · Aug 8, 2018

This happened again last night but this time I switched from Photo back to Video and the feed immediately started working again. Looks like it could be a bug?

Mossiback · Aug 8, 2018

James474474 said:
This happened again last night but this time I switched from Photo back to Video and the feed immediately started working again. Looks like it could be a bug?...]

I will sometimes have minor pixelation that is fixed by switching the camera from photo to video. If you notice, the Go 4 view in video mode has a dark border on all four sides but in photo mode the live stream extends to the edge of the screen. I think that extra coverage taxes my tablet just enough to pixelate the feed.

Jibz · Aug 13, 2018

I still have the same "No signal" error with the video feed going b&w / frozen, at least once every 3 batteries...
Since the RC link remains rock solid every time, I'm starting to think it may be an app or phone problem... I should try with another phone.

James474474 · Aug 13, 2018

Jibz said:
I still have the same "No signal" error with the video feed going b&w / frozen, at least once every 3 batteries...
Since the RC link remains rock solid every time, I'm starting to think it may be an app or phone problem... I should try with another phone.

Are you on android or iOS? I am using a galaxy s7 edge with android 8. Not had the screen disconnect happen since my last post, but if it does happen the first thing I will try is switching between photo and video mode...

Jibz · Aug 13, 2018

I am on Android, using a OnePlus X.

Congoblue · Aug 13, 2018

I have Mavic Pro not Air, but have had this exact problem when switching to HDR mode (using Galaxy S7 non-edge). The only way I got it working again was to get the drone back home and restart it. When I'd recovered from the excitement I tried it again, but it worked fine that time. I think it is a bug in the DJI Go app, kinda alarming though.

vatovec · Aug 13, 2018

Jibz said:
I still have the same "No signal" error with the video feed going b&w / frozen, at least once every 3 batteries...
Since the RC link remains rock solid every time, I'm starting to think it may be an app or phone problem... I should try with another phone.

Had the similar problem on Huawei Honor 8lite, first time I connect to remote and mavic pro works like it suppose to. Second time no signal, RC connected but phone not. Then when I restart the phone he gets the connection.
I've solved the issue by reinstalling dji go4 app and didn't had any problems since.

Lake_Flyer · Aug 13, 2018

James474474 said:
I was filming my son on his bike to practise my flying skills

You did own drones before don't you? You just needed to get comfortable with a Mavic.
But you possess flying skills already right?

That, or you just have a tremendous faith in your first drone. Well, don't. It still is a nasty small grass mower that can crush on your sons head for no apparent reason (for a beginner that is).

Sorry, I can't help myself. I just have to point people to the dangers flying around people (especially on bikes, on the public road) that are always involved. This tech is, although incredible for the price, still somewhat unreliable. In the hands of a skilled operator perfectly safe, but with only a week behind the belt...

OK, hit me guys, I can take it