Today was my first day with my new Mavic.  On the second flight the connection between the remote and aircraft was lost for 28 seconds while 1338 feet away - it was around a corner and there were trees between it and me, with the remote control.  I couldn't see the Mavic but knew it probably should be higher based on the last altitude reading so I started giving it power to go up.  Either it started to return home or I pressed the RTH - I couldn't see it and had lost it against the background of dark mountains.  There was a momentary reconnection and all I could see on the screen were branches!  More up!  At about 43 seconds into the video you can see the branches.  The obstacle avoidance system works great, thankfully.

  

I've attached both the video and a link to the HealthyDrones flight.  I should mention that prior to flying I had a fair amount of trouble calibrating the compass.  It was done like I do with my Phantom 4 which I've never had an issue with and with the Mavic I kept getting "Mag interference" notifications.  From this flight I have some questions:

  

•   1.       Has anyone else had trouble with the compass calibration?
•                 It seems I shouldn’t have lost the signal at 1338 feet.  Obviously the trees interfered, so is this normal?
•                   I had trouble landing the Mavic.  I used the RTH option and it would come down and hover over the orange landing mat I purchased for it.  A message stating the area was not adequate for landing would come on the controller and eventually it would react to the down stick I was giving it and it’d land, but both times about 2 feet away from where it took off from.  I would think that the bright orange mat on snow would provide an adequate landing spot.  Correct?
•           Any other construction comments would be appreciated.
  

      

Thank you.

HealthyDrones link to this flight:

http://healthydrones.com/main?share=QLgsrpYouTube link to part of flight:

Boyyyyyyyy you are lucky. Now for your questions:

  1.       Has anyone else had trouble with the compass calibration?

First why did you do the calibration in the first place?
You need to be away from metal electronic interference etc.


                It seems I shouldn’t have lost the signal at 1338 feet.  Obviously the trees interfered, so is this normal?

You would because you end up behind thick group of trees. You need clear line of sight and correct antenna position.

                  I had trouble landing the Mavic.  I used the RTH option and it would come down and hover over the orange landing mat I purchased for it.  A message stating the area was not adequate for landing would come on the controller and eventually it would react to the down stick I was giving it and it’d land, but both times about 2 feet away from where it took off from.  I would think that the bright orange mat on snow would provide an adequate landing spot.  Correct?

You got to take into consideration, the bright snow and low visibility and wind gust.
It is NOT an exact science. But I'll take 2 feet anytime of the day.

          Any other construction comments would be appreciated.

I don't know how cold it was or how windy it was but cold weather will play a big factor in everything.

Safe flying and don't ONLY COUNT ON YOUR LUCK. Know your terrain and environment.

Has anyone else had trouble with the compass calibration?

I haven't, but I've seen a few other people say they have.

It seems I shouldn’t have lost the signal at 1338 feet.  Obviously the trees interfered, so is this normal?

In my experience, yes it is normal. That looks like a fairly thick bit of forest that was between you and the Mavic when you lost the connection, so I'm not surprised by the disconnect.

I had trouble landing the Mavic.

Again, I've seen a number of other people report this recently. You can work around the problem by disabling "Landing Protection" (under Advanced Settings in the Sensors tab).

Any other construction comments would be appreciated.

You generally can avoid being surprised by a loss of signal by keeping an eye on the signal strength indicator. In this case, for example, I'm guessing that your signal was getting gradually weaker before you lost it completely. If you start seeing the "no bars" or single red bar status, you know it's time to increase altitude and / or bring the aircraft back closer to you. RTH is great and I'm glad that OA saved your Mavic, but you probably have a better chance of keeping the aircraft in one piece if you don't rely on those too much.

DroneFlying Posted at 2017-2-18 19:36
Has anyone else had trouble with the compass calibration?

I haven't, but I've seen a few other people say they have.

Thank you for the tip of watching the signal strength indicator.  I've not had this type of situation with my Phantom 4 so watching the signal strength has not been something I do - I will from now on.

TimmysDad Posted at 2017-2-19 11:22
Thank you for the tip of watching the signal strength indicator.  I've not had this type of situation with my Phantom 4 so watching the signal strength has not been something I do - I will from now on.

We had our Mavic for a couple of days and keep loosing signal as "disconnected" with no camera image on the phone.
No way to get it back. Until we stop aircraft and control and start it all again.
Batteries charged, flying in open zone, no wind, normal temperatures, just a few meters from us.

Anybody knows where we can get a decent users manual where the various functions are clearly explained for pure beginners?

Did not tried to calibrate the compass as we're not supposed to do it on a new aircraft.

fans28bcd95e Posted at 2017-2-19 11:28
We had our Mavic for a couple of days and keep loosing signal as "disconnected" with no camera image on the phone.
No way to get it back. Until we stop aircraft and control and start it all again.
Batteries charged, flying in open zone, no wind, normal temperatures, just a few meters from us.

This explains the Go App at least.

http://fromwhereidrone.com/dji-g ... -every-menu-button/

on DJI.COM there is a section under Mavic with downloads where you can find the latest documentation for the aircraft.

Have you re watched your flight back in the DJI Go app?  You can see if there was a gradual reduction in RC signal or HD.  Looks consistent with the forest getting in the way.

Another thing worth noting is that do you change your RTH altitude for each site your at?  You got very lucky with it returning since it took the shortest route back over the forest.

I was using active track on my car and I had to go pretty fast and lost signal, luckily I set the correct RTH altitude correctly and by the time i got home it was landing in my drive like a good girl

Bradz Posted at 2017-2-19 11:59
Have you re watched your flight back in the DJI Go app?  You can see if there was a gradual reduction in RC signal or HD.  Looks consistent with the forest getting in the way.

Another thing worth noting is that do you change your RTH altitude for each site your at?  You got very lucky with it returning since it took the shortest route back over the forest.

Just read on a different thread that the loss of connection can be avoided when using the phone on airplane mode.
Just tried it for a few minutes and it worked !
Will have to use on longer trips and see what happen.
So far so good especially when there is no way to update the firmware but that's a different thread.;.

fans28bcd95e Posted at 2017-2-22 05:40
Just read on a different thread that the loss of connection can be avoided when using the phone on airplane mode.
Just tried it for a few minutes and it worked !
Will have to use on longer trips and see what happen.

By the way it is absolutely ridiculous that we have to rely on a forum with users to get replies by themselves and that DJI is useless here.

fans28bcd95e Posted at 2017-2-22 05:40
Just read on a different thread that the loss of connection can be avoided when using the phone on airplane mode.
Just tried it for a few minutes and it worked !
Will have to use on longer trips and see what happen.

Yeah but then you don't get any data which the DJI GO app needs for maps and flight restrictions.  Have you tried turning of just WIFI and BT?  I keep forgetting to do it but I'm going to try that next before airplane mode.

weather too cold?

Bradz Posted at 2017-2-22 23:34
Yeah but then you don't get any data which the DJI GO app needs for maps and flight restrictions.  Have you tried turning of just WIFI and BT?  I keep forgetting to do it but I'm going to try that next before airplane mode.

If we turn off Wifi, Bluetooth + you say we can't use airplane mode, that means that the phone needs a connection to regular phone network via 3G or 4G.
What happen should you use the drone in the middle of nowhere with no phone network??

I never tried but can we fly with just the remote control and no phone?

fans28bcd95e Posted at 2017-2-23 11:04
If we turn off Wifi, Bluetooth + you say we can't use airplane mode, that means that the phone needs a connection to regular phone network via 3G or 4G.
What happen should you use the drone in the middle of nowhere with no phone network??

The phone just acts as a computer, GPS and display, you do not need service (or a sim card) for the drone and app to work.
Regards,
-d.

I have been using a Samsung tablet S8 for all my flights since day one and have not had one disconnect. The tablet itself is not on a network but does have an internal GPS that works well. It is dedicated solely for my Mavic.

Vegetation contains water, especially trees.  Water blocks/attenuates the higher frequency RF that is used for your link.  Keep your antenna parallel to the location of the drone at all times in order to maximize the amount of signal between the drone and the controller.  Stay above horizon at all times.

AG0N-Gary Posted at 2017-2-23 11:21
Vegetation contains water, especially trees.  Water blocks/attenuates the higher frequency RF that is used for your link.  Keep your antenna parallel to the location of the drone at all times in order to maximize the amount of signal between the drone and the controller.  Stay above horizon at all times.

Thank you. I guess I pay attention to this.
But loosing connection at 20meters on an aircraft that has a supposed range of several miles because it's too low on the horizon or the antennas not really "straight'"???

bunny too Posted at 2017-2-23 11:09
The phone just acts as a computer, GPS and display, you do not need service (or a sim card) for the drone and app to work.
Regards,
-d.

But then what are we loosing in airplane mode?
The GPS can stil be activated on airplane mode, we are just loosing the phone and phone network so where is the point?

-----------------

fans28bcd95e Posted at 2017-2-23 11:04
If we turn off Wifi, Bluetooth + you say we can't use airplane mode, that means that the phone needs a connection to regular phone network via 3G or 4G.
What happen should you use the drone in the middle of nowhere with no phone network??

Use AP mode by all means but I wouldn't want to turn off cellular data when I don't have too unless its proven to be better.

If there's no signal than there is no signal.

Bradz Posted at 2017-2-24 01:44
Use AP mode by all means but I wouldn't want to turn off cellular data when I don't have too unless its proven to be better.

If there's no signal than there is no signal.

I can confirm that I can fly with no loss of connection on Airplane mode.
The App crash all the time now on my phone, there is no way to use it ... except on Airplane mode.
My Samsung Expire 3 is almost dead though and I have to replace it. This could also explain that.