Went out today to a local lake to fly, i'v been here before two times and i'v gotten excellent GPS signal and RC signal, and had no issues in this area before.

Calibrated like i always do, and while doing so i noticed the app  switch between atti/gps mode back and forth while doing the calibration dance.. but upon completion i got a green signal and around 18 gps connected, the MOD value was around 1500,  and the rc signal good. so away i went.

Flew up 150m and around 450m from the bridge where i lifted off, then all of a sudden i simply lost connection (according to the DJI GO APP) no warnings regarding week RC signal or nothing just went from normal to no connection.

Got quite nervous to say the least.. :-)

Had to compose my self a little...switched to atti mode and to my relief the aircraft seemed to respond, got my bearings (kind of hard to tell the direction that far away) and brought it suprisinlgy easy home to the bridge where i stood. Luckily there was not very windy so flying in Atti was far easier then i imagined it to be.


I never touched the RTH as i rather fly it manually then rely on it landing on the bridge by it self, now in hind sight i could of course let it fly it back to me and land it manually but i was a little worried about the GPS not being up to the task.

First i thought i probably lost signal to interference and that as soon as i got it closer to me the app would re-establish the connection. No such luck.

So safe on the ground i turned everything off and then on again,now i got a compass error.. re-calibrated (with the same switching from atti/gps mode) and got a green signal with good mod values.  

Not very interested in trying to replicate the problem on the bridge, i  moved to a open grass field instead.. :-)

Got good gps signal, calibrated (this time without any switching between atti/gps) and everythings fine.

Replicated the problem by simply pulling out the usb cable from the RC controller, got me the same result no connection but full control of the aircraft.

I assume this was a error with my ipad mini 2 and the APP, by simply restarting the app i might have gotten connection back ?  sadly i didn't try that when i was on the bridge, i was to focused to get it back in atti mode. :-)

Any theories ?

Naturally the flight records shows only up to the point where i lost connection with the app. The video recorded without any issue though. :-)

Thanx!

Like you say to others you should have RTFM lol

Willie Wonka Posted at 2015-8-30 22:45
Like you say to others you should have RTFM lol

Judging by your response i assume there is a obvious explanation to be found in the manual. I'v read the manual, but  be so kind to point out where in the manual i get an explanation as to why i got a lost connection ?

What does the manual state i should have done opposed to the cause of action i took ?


Im curious to the reason is all, knowing it might not be as big of a mystery as you'r factory of course.

Very simple , if you have a green light on the r/c then just restart the app and reconnect the USB  cable, and all your worries are gone. As I have tested all these situations on my self to make sure I am in control when it happens all of the sudden, it's called flying smart.

Willie Wonka Posted at 2015-8-30 23:27
Very simple , if you have a green light on the r/c then just restart the app and reconnect the USB   ...

Thank you, where in the manual can we read this ? Any theories to the reason of the lost connection? As the app has never crashed nor did the app crash now...

Testing for various scenarios is indeed flying smart, the main reason i practiced atti mode for the moments when GPS fail, and i need to be fully in control.

I never read the manual so i should repurpose the famous letters from RTFM to UOPBEAM (use other people bad experiences as a manual).

As mentioned other places, loss of signal error is not loss of RC to P3 communication.  It just means you have no video signal *(supposedly).  I've let the bird hover and completely rebooted the phone to get it back when nothing else would.  As you found, you can still control/fly the bird.

I'm wondering about your compass error though.  You say you launched from a bridge?  A bridge likely has plenty of steel rebar in it and would/could affect compass calibration.  Just a possibility to consider.  Even on open ground, be sure there is no underground plumbing or electrical wiring or conduit under your location that could affect it.  I sometimes do an overhead compass calibration to get away from whatever might be buried beneath me.  You played it safe.  I did too the first time that happened.  I now just reboot the program and try again.  If that doesn't do it, I reboot the phone.  This loss of signal thing seems to be a temperature and/or horsepower issue  with the phone/tablet that is running the app.  Hopefully they will get things trimmed up so it doesn't take a Cray to fly it.

*By the way, some of my earliest "loss of signal" issues actually had the red bar and no signal message with no other symptoms.  The video was still good, and all functions worked fine.  It said no signal until I landed and restarted everything.

I also fly most of the time in airplane mode.

Thanx for the response Ag0n.

Yes there was no RC to P3 connection error evidently. No video signal or any other connection, the app did not get any data from the aircraft the gps didn't give a orientation of the p3 or anything.

Yes i launched from a bridge, a wooden bridge though so i doubt it was the issue, but it is odd regarding the compass error as i'v flown from that bridge before with no error what so ever.


Regardless it seems to be a issue with the app/tablet easy enough to fix.

Will try some different scenarios later this week, and also practice more on ATTI mode i have the feeling that one day it will  save my bacon.

Wooden bridges can still have a surprising amount of iron or steel in them, probably best to work from a ground surface away from any structures.

Thanx Geebax, this however does not, its a small bridge. But it is possible it was the reason behind the compass error as there really is no other structures nearby the place where i did the calibration. (besides a guy fishing and his rods.. )

Just another datapoint here.....I've had my app crash and "google Services" stop more times than I care to mention on my Android NVIDIA shield tablet.    First few times I needed to change my shorts after the panic attack.  HOWEVER, I have always determined that controller itself is still controlling the aircraft.  Therefore, I just let the aircraft hover, while I ensure I completely closeout the app and the restart the app and voila, it reconnects and I'm back in business.

I will give DJI a TON of credit here for the way they've implemented the software.   The Contoller's hardware itself is what really controls your drone and if the app crashes, you still have control of the drone with your RC if you are within safe distance and electrical line of site of your helicopter.  

I have even just pressed RTH on the RC when my app completely crashed and the aircraft started it's journey back while I fiddled to get the app to restart....app restarts and say "Go HOME"  and I'm back in visual control.

I can attest that as little as 4 - 3/8" x 6.5" long carriage bolts with 2 nuts and 2 washers on each bolt was enough to mess with my compass.  I used them as legs on my Heli-Pad and was astounded that I was getting the "toilet bowl" effect right after I took off and hovered a bit.  These birds are super sensitive to metal.  Needless to say I will not be using those legs any more.

Hi Paul,

Trying to chime in to help, not rain on your parade. You contradict yourself saying that there was no RC -> P3 connection. If you were able to control/ fly the P3 in any way with the RC, you obviously had a connection. You said that you flew it back in ATTI mode, sooooooo RC-> P3 connection was still there.

It seems it was just a lost connection between the app and the remote, in which case you are in full control, nothing to worry about really- as long as you have LOS to the P3 & can bring it back home safely... which you did!

Now to the root of this "problem":
Have you checked that you have a well-working usb cable for connection to your phone/ tablet?
I don't remember if you mentioned which device(s) you are using...? I personally fly with an iPhone 6+ & and an iPad Air 2. I can verify that flying with some cables are much better than others, particularly the OEM iPhone cables work better for me. I have done a bit of research on this as I do not like flying with all 2 meters of cable bunched up, or dangling, from my RC.
So I have bought numerous usb-lightning cables of varying lengths to try to resolve this. I have found that anything other than an Apple OEM cable seem to lose connection to the app randomly. In fact, I believe that they drop connection to the phone momentarily, which makes it seem like the app. Also, check that the cables are in good condition. I have one cable from a iPhone 5 that has been around a while, it doesn't work so well as i think it has been a bit abused. I can recreate the APP-->RC disconnect just by wiggling the USB end of the cable at the RC. Also, the iPad seems to be more sensitive to the cable type to me. The phone, not so much.

Just my 2-cents.

Hi Flyhigh!

Thank's for chiming in, but where did i claim there was no RC->P3 connection ? I wrote according to the app there was no connection to the aircraft. When i saw the aircraft respond to my input i knew there was a connection obviously, and my first assumption was also that the ipad failed and i would have gotten back the feed by simply restarting the app. (which i later confirmed)

As for the root of the problem, i use only apple OEM (this case a 50cm) cables to my ipad mini 2.  First thing i checked when back safely was if the cable was at fault, no matter how much i wiggled it couldn't replicate the problem.

Been using the cable and the ipad min 2 since day one, not a single fault near to 100 flights, so I'm not sure what caused it. But will keep an eye on the cable and ipad if it happens again.

Thanx!

jayhkr Posted at 2015-8-31 06:53
I can attest that as little as 4 - 3/8" x 6.5" long carriage bolts with 2 nuts and 2 washers on each ...

Thanx!

Will keep that in mind! Even more the reason to master atti i guess. :-)

paullindqvist Posted at 2015-8-31 12:35
Hi Flyhigh!

Thank's for chiming in, but where did i claim there was no RC->P3 connection ? I wrote  ...

my bad, maybe i read incorrectly. it is still early for me being monday and all, pretty much until tuesday it will be early. mondays are just harsh...

Flyhigh7887 Posted at 2015-8-31 13:01
my bad, maybe i read incorrectly. it is still early for me being monday and all, pretty much until ...

Haha yea i hear ya :-)  I'm fortunate enough to be self employed so i quite like Mondays. .-)

paullindqvist Posted at 2015-8-31 07:09
Haha yea i hear ya :-)  I'm fortunate enough to be self employed so i quite like Mondays. .-)

Well, some of those comments bordered on being a little harsh, but ultimately got much softer! Personally, I thought maybe at first you confused the difference between the RC/Phantom connection and the status of the GO app. The manual (there *is* a manual for the app isn't there? Oh there's not - Oh that's right!) doesn't say anything about rebooting the app either.

My flight experiences are very much like yours. I'm seldom looking at the screen except to frame a video shoot (haven't done hardly any stills with mine) and generally I'm keeping a "hawk eye" on my Phantom. I think you did just fine. Despite perhaps not realizing you still had a connection between the Phantom and your controller, your sane, steady actions resulted in a joyful ending. I think you're to be commended. My app has crashed so many times that once I've got my Phantom in the air, I hardly ever look at my app screen. I just keep the Phantom in sight, try to make certain I'm aware of the orientation (i.e., which way is it facing?), etc. Typically, I discover the app has crashed when I glance down to see the battery condition and discover the app has stopped. Don't know what I'd do if those LEDs were not on the back of the battery! If the Phantom is not too, too far away, those LEDs really help both with battery level and orientation.