Dodged a bullet today…Flew from my front yard about 1/4 mile down the road (lots of trees) to a big open field. For the first time ever I got a low transmission signal warning and then immediately an Aircraft disconnected message. I waited for a few seconds thinking return to home would initiate. When it didn't, I pressed the return to home button. I did not get a verbal message telling me it was coming home, but the return to home button was blinking and making a ticking sound like it usually does. After 15 minutes of waiting, I knew it wasn't. Needless to say I freaked out a little bit. I hopped in my car and tore off towards the field. When I got there, there was my drone sitting in the middle of the field. It was in some tall grass; nevertheless the gimbal was absolutely fine.I checked my return to home settings and make sure that it was set to return to home and not hover in place. So my question is why did it not initiate return to home when it lost signal? Am I confused or is that what it is supposed to do? I have manually initiated return to home in the past, but this is the first time that I ever lost signal and had the aircraft disconnect.
When I got back to my house, I flew it up to about 100 feet and then hit the return the home button. Voice said coming home and it started flying back towards me, so I know that the function is working properly. Any thoughts on this would be helpful. Thanks!

Man, I thought someone had brought out the sniper rifle.


Click bait?


Glad your drone was fine, and you as well. ;-)



RedHotPoker

Most likely explanation is that it did initiate its return to home when it lost signal for more than three seconds. By time it climbed to its RTH height it may have regained control signal (video is a separate signal), just in time for you to cancel the RTH by pushing the RTH button. It then hovered in place waiting for your instructions, until battery ran low and it landed itself.

The detail would likely be in the flight record, if you upload to Phantom Help some of the experienced pilots here may be able to verify if that's what happened.

Aardvark sounds spot on.

The issue may happen when you regain the control. It's lucky that the drone is fine.

Did you use the "find my drone" function?

This is why every once in a while I test my "return home" button to make sure it works properly in plain site.

Aardvark Posted at 2017-9-21 14:08
Most likely explanation is that it did initiate its return to home when it lost signal for more than three seconds. By time it climbed to its RTH height it may have regained control signal (video is a separate signal), just in time for you to cancel the RTH by pushing the RTH button. It then hovered in place waiting for your instructions, until battery ran low and it landed itself.

The detail would likely be in the flight record, if you upload to Phantom Help some of the experienced pilots here may be able to verify if that's what happened.

Aardvark
Have you got any advice on how you should deal with a situation like this?  Specifically, you assume RTH is automatically initiated but then it seems nothing is happening so you hit RTH and end up canceling it, how do you not screw yourself in the process of unscrewing yourself?
I had thought that maybe it did not RTH because it lost GPS, but at present that can't be proven one way or the other.
Love to hear your thoughts on this, please.

Genghis9 Posted at 2017-9-21 20:19
Aardvark
Have you got any advice on how you should deal with a situation like this?  Specifically, you assume RTH is automatically initiated but then it seems nothing is happening so you hit RTH and end up canceling it, how do you not screw yourself in the process of unscrewing yourself?
I had thought that maybe it did not RTH because it lost GPS, but at present that can't be proven one way or the other.

I generally fly with aircraft in sight (as long as I don't blink) so have never had to deal with a loss of control signal.

Best way to deal with it would be to do nothing, at least until visual signal returns, where you can take control again.

In above case there is the possibility that the RTH was cancelled. Also when aircraft is climbing to its pre-set RTH height (say 60m) then once it gets above an initial minimum of 20m then any operation of left hand stick will cause it to stop climbing and return at present height (anywhere between 21-60m in example). So you can see the potential problems. Had it been loss of GPS (not likely in an open area) then the RC would have been screaming ATTI mode.

The best thing to do is get out into a wide open field and test out the various situations, or the flight sim makes a good second best in that it closely emulates what would happen in reality. So that if/when it happens you will understand what the aircraft should be doing.

So to recap', initially put RC safely down where it can't be disturbed. Then adopt crash position (head between knees etc), and wait for it to come home. If after ten minutes or so it doesn't, then extract head (you may be feeling a bit dizzy by now) and start hunt based on a straight line to last known position on flight record :-)

Aardvark Posted at 2017-9-22 11:02
I generally fly with aircraft in sight (as long as I don't blink) so have never had to deal with a loss of control signal.

Best way to deal with it would be to do nothing, at least until visual signal returns, where you can take control again.

Thank you, always helpful
Sounds like sage advice, I hope I don't run in to such a situation but part of avoiding such circumstances is being prepared and knowledgeable about them.

this is absolutely normal, this product unfortunately not very reliable, the dji-go application often crashes and warning loss of connection often happen to us ...

Genghis9 Posted at 2017-9-21 20:19
Aardvark
Have you got any advice on how you should deal with a situation like this?  Specifically, you assume RTH is automatically initiated but then it seems nothing is happening so you hit RTH and end up canceling it, how do you not screw yourself in the process of unscrewing yourself?
I had thought that maybe it did not RTH because it lost GPS, but at present that can't be proven one way or the other.

by experience it is enough to keep the button rth to activate the return, even without being connected

Olivier Vietti- Posted at 2017-9-22 12:13
by experience it is enough to keep the button rth to activate the return, even without being connected

understood and thanks

Well, I took my drone into an open field today with a fully charged battery. Flew up to 125 feet in height and about 200 feet in distance. Turned off the controller  and after a few seconds the drone turned around and came back home. I tried it several times. I also manually initiated return to home and he performed flawlessly every time.  I confidence has been restored in its reliability. I don't know what caused the original problem, but it would seem to be the exception not the rule. Thanks to everyone who offered advice.

Olivier Vietti- Posted at 2017-9-22 12:13
by experience it is enough to keep the button rth to activate the return, even without being connected

If you lose connection with the Phantom, there is no way you can initiate RTH using the controller.
But the Phantom is programmed to RTH itself 3 seconds after losing control signal.

It's quite possible that your loss was due to other misunderstandings of how it operates.
Until you post your recorded flight data, we'll never know.

Genghis9 Posted at 2017-9-21 20:19
Aardvark
Have you got any advice on how you should deal with a situation like this?  Specifically, you assume RTH is automatically initiated but then it seems nothing is happening so you hit RTH and end up canceling it, how do you not screw yourself in the process of unscrewing yourself?
I had thought that maybe it did not RTH because it lost GPS, but at present that can't be proven one way or the other.

This just might be an argument for DJI to change their approach to the way RTH is disabled with a second button press. The only reason I want to press the RTH button, is to make the Phantom RTH. If the bird is already on it’s way home but I don’t know that, and pressing RTH cancels what I absolutely want it to do...
I’ve got to quit reading this forum. Every scenario of doom is readily available to cause my blood pressure to rise just after each CSC.

Jeff

Aardvark Posted at 2017-9-22 11:02
I generally fly with aircraft in sight (as long as I don't blink) so have never had to deal with a loss of control signal.

Best way to deal with it would be to do nothing, at least until visual signal returns, where you can take control again.

To date I’ve only needed the RTH function 3 times using a Phantom 1. Each time, I turned the controller off and waited for the magic. Each time I was rewarded with the P1 landing where it took off. Aardvark, your post just cements what I will do if I ever see the app disconnect. I’m turning the controller off and waiting patiently for my P4 to come home on its own.

Jeff

Jeff Millard Posted at 2018-2-14 06:04
This just might be an argument for DJI to change their approach to the way RTH is disabled with a second button press. The only reason I want to press the RTH button, is to make the Phantom RTH. If the bird is already on it’s way home but I don’t know that, and pressing RTH cancels what I absolutely want it to do...
I’ve got to quit reading this forum. Every scenario of doom is readily available to cause my blood pressure to rise just after each CSC.

Yes
I think your point is, the RTH button is only for initiating RTH.  Therefore if you want to cancel a RTH command you should be prompted for it on the APP however if flying with just the controller only (you can do that) then maybe the RTH button color needs to change confirming RTH was initiated so that way you don't cancel something you meant to initiate.

Yeah...I guess it could be a bit nerve racking, but the best way to prepare for an abnormal or critical situation is to review and then review again.  For me, I just look at these events and situations as nothing more than 'what if' scenarios that can help me think through what I'll do in advance if it were to occur to me.  All in all, best advice is to not over think this stuff.

Jeff Millard Posted at 2018-2-14 06:08
To date I’ve only needed the RTH function 3 times using a Phantom 1. Each time, I turned the controller off and waited for the magic. Each time I was rewarded with the P1 landing where it took off. Aardvark, your post just cements what I will do if I ever see the app disconnect. I’m turning the controller off and waiting patiently for my P4 to come home on its own.

Jeff

Everyone has to do what they think is best, speaking for myself, I couldn't turn off the RC. I've only used RTH a few times, but I would always take control of it as soon as it was close. I try to always keep it in line of sight, however, it can be there one second, look down at the display, look up and it's gone!  If there's any glitch in the video transmission, you can get disoriented very quickly.  I just like to keep every possible means of control at my disposal.  Again, to each their own!

Genghis9 Posted at 2018-2-14 06:40
Yes
I think your point is, the RTH button is only for initiating RTH.  Therefore if you want to cancel a RTH command you should be prompted for it on the APP however if flying with just the controller only (you can do that) then maybe the RTH button color needs to change confirming RTH was initiated so that way you don't cancel something you meant to initiate.

You seem to have the ability to calmly react under pressure. I turn to jello. When there’s an emergency, I’m the guy who volunteers to meet the ambulance and lead it to the victim for what I understand as obvious reasons . But I do think they’ve created a serious problem using the exact same action to start and then stop RTH.
I agree with you not to over think it. I have to drill it down, and in doing so I still come up with the idea that turning the controller off would be best. It would ensure the RTH function is activated due to loss of signal. And there would be no chance for me to accidentally deselect the RTH.

Jeff

Had the same thing happen to me... problem is RTH didn't work, RC signal never came back, drone never found, DJI claims they can't replace it because I haven't found the drone... AWESOME DJI huh ?

My philosophy is that if it loses signal, my hands stay off the sticks and I just let her come home naturally.

Timinator Has the right idea. If you watch the distance, it will reconnect faster than the video and you can see if it is coming towards you. If so just let her come until you can see her again. I can't believe you waited 15 minutes to go look for it. I am a patient man but after 2 or 3 minutes with nothing happening I would be after it!

BenchZowner Posted at 2018-2-14 17:08
Had the same thing happen to me... problem is RTH didn't work, RC signal never came back, drone never found, DJI claims they can't replace it because I haven't found the drone... AWESOME DJI huh ?

Great idea, anyone who wants to replace their drone just calls DJI and tells them it never came home. Put yourself in their shoes, would you give a replacement to someone who could not produce the aircraft for examination. If you would, then I have a couple of bridges I would like to sell to you.....

Jeff Millard Posted at 2018-2-14 16:33
You seem to have the ability to calmly react under pressure. I turn to jello. When there’s an emergency, I’m the guy who volunteers to meet the ambulance and lead it to the victim for what I understand as obvious reasons . But I do think they’ve created a serious problem using the exact same action to start and then stop RTH.
I agree with you not to over think it. I have to drill it down, and in doing so I still come up with the idea that turning the controller off would be best. It would ensure the RTH function is activated due to loss of signal. And there would be no chance for me to accidentally deselect the RTH.

Sounds like you can reason through things just fine if you have too.
As for myself, well call it occupational hazard...I've dealt with a few near death experiences and inflight emergencies...those events can put things in their proper perspective every time.  
One thing is for certain, I've never found where panicking helped solve anything...and that you can take to the bank.

Jeff Millard Posted at 2018-2-14 06:04
This just might be an argument for DJI to change their approach to the way RTH is disabled with a second button press. The only reason I want to press the RTH button, is to make the Phantom RTH. If the bird is already on it’s way home but I don’t know that, and pressing RTH cancels what I absolutely want it to do...
I’ve got to quit reading this forum. Every scenario of doom is readily available to cause my blood pressure to rise just after each CSC.

That sounds like not a bad idea on changing RTH cancel method, perhaps C1 + C2 to cancel, but only when in RTH mode. So aircraft goes out of range, after three seconds initiates RTH and flies back. In the meantime panicked operator has been and still is pushing RTH. But because of new reset method it continues home. Operator realises he now has video returning and decides to let it return, or take control by pushing C1+C2.
P4 within 20m, operator pushes RTH, aircraft landing in muddy puddle (not many swimming pools in Scotland), operator presses C1+C2 (or similar) to cancel.

You should post that idea to them Jeff, in the 'support' section in DJI Go 4, there's a suggestions tab.

They modified the engine cut off in flight for the P4 series, so why not this :-)

Aardvark Posted at 2018-2-15 14:15
That sounds like not a bad idea on changing RTH cancel method, perhaps C1 + C2 to cancel, but only when in RTH mode. So aircraft goes out of range, after three seconds initiates RTH and flies back. In the meantime panicked operator has been and still is pushing RTH. But because of new reset method it continues home. Operator realises he now has video returning and decides to let it return, or take control by pushing C1+C2.
P4 within 20m, operator pushes RTH, aircraft landing in muddy puddle (not many swimming pools in Scotland), operator presses C1+C2 (or similar) to cancel.

I'm humbled. Thank you, and I did as you suggested. I've relied on the RTH to bring my P1 home before. I was grateful it worked every time. It wouldn't surprise me in the least, if I was the guy who lost a P4P because I was at fault for stopping the RTH when I needed it most. That's my luck in a nutshell.

I do think the way it's designed to work now, combined with the common "black screen/aircraft disconnected" issue, is setting people up for interrupting the RTH feature. With the end result being a hovering bird running the battery down and landing in place at 10%. If that's over water... ouch! But the OP's story, and the next few posts seem to confirm that this is what can happen with a certain set of circumstances. Unless something changes with the function of the switch, I'm sticking with "operator initiated loss of communication" via the controller power switch. It's made my P1 come home every time I lost sight of it.

Jeff

...and one more thing: "if I was the guy who lost a P4P because I was at fault" or even if it just flew away on it's own and I couldn't find it or prove it, DJI has me. They have their hooks in me deep. There is a connection between me and this bird. (The P4P, not my specific acft) If I were to lose it, I'd jump at that discount they offer and I'd have another here as soon as FedEx could deliver it.

Jeff

Geebax Posted at 2018-2-14 21:08
Great idea, anyone who wants to replace their drone just calls DJI and tells them it never came home. Put yourself in their shoes, would you give a replacement to someone who could not produce the aircraft for examination. If you would, then I have a couple of bridges I would like to sell to you.....

For starters, they are saying ( in the chat and on the site/manual ) that having the drone isn't necessary ( really, I would love to see them ask Casey Neistat for example to find his flyaway drone that started to fly on its own and headed far into the ocean ).

Second of all, they have all the flight logs and proof needed.
In my personal case, they also have all my searches traced on Google Maps ( Location History ).

And lastly, they can easily make DJI Go4 app ( and all the sibling 3rd party apps ) log to their servers whenever a drone flies, so they could easily see if I have or don't have my drone.