Hello, there.
Sadly my first post here is about loosing my aircraft. Last afternoon my MAVIC PRO was lost. After flying for 1,5 minutes the DJI GO 4 app disconnected out of a sadden and I lost control. The distance to the aircraft was 150m. The flight controller was still showing some data like RPM, height etc but the app couldn't connect until the battery was drained and the aircraft landed somewhere on a rooftop(?). I've been searching for the whole afternoon since night fall to no avail.
My flight is this:
https://app.airdata.com/main?share=yYQvVQ

I've flewn from the same point several times before without any problem. The day before that I flew the aircraft to a much longer distance, I had a disconnect but successfully RTH'd.

Can anyone tell me what was wrong from the log files? I don't seem to find any problem. The aircraft is 3 months old.
Today I'll go search for it on nearby buildings, I hope I find it. I'll update this post.

Do I need to attach the original .DAT flight log just in case anyone can help?

That has happened to me before. The only way of regaining connectivity to your phone when that happens is to turn off the controller and then turn it back on. Other than that you still have control over the craft and should have pressed the RTH button on the controller. So sorry you lost your bird

Sorry for your loss.

This will not help you directly, but the same happened to me several times with the pro. Plugging in and out the connection cable between iphone and controller helped. Twice I a had to restart the app for this trick to work. But always the drone was responsive to the controller, and I was able to control/land it. But as I did not want just to fly it, but to take pictures, this was not very helpful. The last few times I just continued to fly after restart of the app, and the cable trick, and then took some pics.

Then I changed the cable. Still waiting for the problem to happen with this one.

Hope that you can find your drone soon. Sorry about this but hope for the best

Bums me out to hear you lost her

This just happened to me the other day in fact, app locked up tight and yes i know, hindsight is always 20/20 but,......Push the ascend stick up to check if the RC is still connected or not by watching RPM on the RC display, if responding, hit the RTH button on the RC, she'll come home........

Has  anyone tried using a Tracker on their Drone ?

https://www.amazon.com/Loc8Tor-L ... o+and+Visual+Finder
Kind of pricey.

It happened a couple of times with my a android phone. A couple of tips can be found in this thread Issues
I switched to iOS (ipad mini 4) and have no issues anymore.

chiplifter Posted at 2018-7-13 23:03
It happened a couple of times with my a android phone. A couple of tips can be found in this thread Issues
I switched to iOS (ipad mini 4) and have no issues anymore.

Agree Android seems to have a lot more disconnects then Ios, I have also went over to Ios and no issues since

chiplifter Posted at 2018-7-13 23:03
It happened a couple of times with my a android phone. A couple of tips can be found in this thread Issues
I switched to iOS (ipad mini 4) and have no issues anymore.

Guy in our drone club with Ipad Pro got disconnected today.  He really freaked out. "What do I do now!" So I went over and showed him he still had the RC connection. His batt was at 85% so he had plenty to return with. I used that time to show him how to interpret the data off the RC and get orientation as well as the craft back.

He panicked like others, and that leads to bad things. I taught him how to close the distance using the RC. He was nervous about doing this. After a few tries he said "I have it now!! Yeah !!"

He was about 1200 feet out when he got disconnected. Ipad was not in Airplane mode, which could have been part of the problem. He's not the first with an iOS device disconnect either. Last time out my Mini4 was getting choppy blocks of black/gray in the video. Not real bad, but enough to notice. Had some latency as well. Today same kit, same settings, and I ran a couple batts worth no problems.

Hi. I am sorry to know what happened to your previous flight and what happened to your DJI Mavic Pro. Since the Drone was lost please create a ticket using the online repair request link ( www.dji.com/support ) for us to know what really happened to the Drone please sync the flight records as well.

Everyone, many thanks for your suggestions. Luckily I've FOUND THE DRONE and I'm very happy right now! After a very tiring day  and lot's of searching I ended up going up to the top floor of the highest building in the area and searching the area with my binoculars. Found it on top of a roof around 200m from the home point! It seems that it landed smoothly after the battery got drained.


A big omission of the remote controller is the lack of displaying the aircraft bearing. If I had this display (the app disconnected/crashed but the RC still showed info rpm/height etc) maybe I'd have turned it to my position and bring it to line of sight or even land it near me.

Lesson learned: never let it fly without first locking all satellites and marking the home point.

Again, thanks everyone for the help and I'll be sure to get some kind of tracking device as it seems it's useful even in short range flights.

DJI Stephen Posted at 2018-7-14 09:36
Hi. I am sorry to know what happened to your previous flight and what happened to your DJI Mavic Pro. Since the Drone was lost please create a ticket using the online repair request link ( www.dji.com/support ) for us to know what really happened to the Drone please sync the flight records as well.

Thank you Stephen. I've already sync'd the problematic flight record. No need to create a ticket as I've found the drone.

chiplifter Posted at 2018-7-13 23:03
It happened a couple of times with my a android phone. A couple of tips can be found in this thread Issues
I switched to iOS (ipad mini 4) and have no issues anymore.

Thank you sir, really useful.

Asainz320 Posted at 2018-7-13 21:06
That has happened to me before. The only way of regaining connectivity to your phone when that happens is to turn off the controller and then turn it back on. Other than that you still have control over the craft and should have pressed the RTH button on the controller. So sorry you lost your bird

Pressed madly the RTH but the aircraft didn't respond. I was blind until the battery drained. If there was some bearing display maybe I could've brought it back home. All ended well though as I found it on a rooftop.

thanos.szs Posted at 2018-7-14 11:01
Pressed madly the RTH but the aircraft didn't respond. I was blind until the battery drained. If there was some bearing display maybe I could've brought it back home. All ended well though as I found it on a rooftop.

Did you try to long press the RTH button? For me RTH doesn't initiate after a simple quick press, but a 1-2 second one worked. Anyway glad to see you got your bird back

thanos.szs Posted at 2018-7-14 11:01
Pressed madly the RTH but the aircraft didn't respond. I was blind until the battery drained. If there was some bearing display maybe I could've brought it back home. All ended well though as I found it on a rooftop.

Are you sure? Pressing the RTH button more than once will land the drone.
The best thing is to press it just once for 2 or 3 sec.

Kewl story since you know where it is now. How do you plan on getting the Mavic into your own hands? You know the people that own the building it is sitting on?

Zsolti Posted at 2018-7-14 11:32
Did you try to long press the RTH button? For me RTH doesn't initiate after a simple quick press, but a 1-2 second one worked. Anyway glad to see you got your bird back

TBH I faintly remember I did that. I was in panic. Anyway, I'll test it again today to check.

G_Sig Posted at 2018-7-14 12:10
Are you sure? Pressing the RTH button more than once will land the drone.
The best thing is to press it just once for 2 or 3 sec.

Can't tell what the drone was doing after I pressed. I'll check it today to see now it's back in life.

rolling56 Posted at 2018-7-14 12:20
Kewl story since you know where it is now. How do you plan on getting the Mavic into your own hands? You know the people that own the building it is sitting on?

Already got it. I asked the owner to let me climb on the roof from the other side and retrieved it with a long hooked stick very very carefully to avoid breaking the tiles. Thank god it didn't rain during the night. All is well now and I'll check it the functions today.

thanos.szs Posted at 2018-7-14 10:52
Everyone, many thanks for your suggestions. Luckily I've FOUND THE DRONE and I'm very happy right now! After a very tiring day  and lot's of searching I ended up going up to the top floor of the highest building in the area and searching the area with my binoculars. Found it on top of a roof around 200m from the home point! It seems that it landed smoothly after the battery got drained.
[view_image]

woo~so good you can find your drone lucky.
And hope this won't be happened again in your future flight life

thanos.szs Posted at 2018-7-14 10:56
Thank you sir, really useful.

You are welcome. Maybe another tip, if the phone disconnects from the sideport usb, remove the cable in flight and replace with a standard usb-cable to the bottom connector of the controller.  For few a dollars available in any electronics shop. Do not forget to remove the cable from the sideconnector completely. If cable is plugged in in the sideconnector the bottom connector is disabled.

thanos.szs Posted at 2018-7-14 21:13
Already got it. I asked the owner to let me climb on the roof from the other side and retrieved it with a long hooked stick very very carefully to avoid breaking the tiles. Thank god it didn't rain during the night. All is well now and I'll check it the functions today.

Great to hear that all ended well!

Not yet material for a movie, but nevertheless a good story finding back your drone, glad you get to fly another day.
App disconnection doesn't always mean that you lost telemetry. If the live view cuts out, you may want to switch to radar view. That little circle tells you the heading of the craft in relation to your position, and it's then easy to point the craft to you and fly back manually.

thanos.szs Posted at 2018-7-14 10:52
Everyone, many thanks for your suggestions. Luckily I've FOUND THE DRONE and I'm very happy right now! After a very tiring day  and lot's of searching I ended up going up to the top floor of the highest building in the area and searching the area with my binoculars. Found it on top of a roof around 200m from the home point! It seems that it landed smoothly after the battery got drained.
[view_image]

Here's what you do. If you have the craft out and get disconnected, DO NOT yaw, turn etc. Stop. Look at the last map direction indicator. When my app has crashed, the direction stays as it was. Only the ap is down and not updating. STOP and now look at the Remote distance number.

That should be the last known direction and craft orientation. If it looked as if it was pointed away, go ahead and push the R stick forward look at the distance telemetry. You want the craft distance to close from your location. Number should go down. If it goes up, push the stick the opposite direction.

Now you should have an idea of the craft heading back towards you. Still not sure of orientation. For that, you can view the distance data. If the closing distance seems very consistent, you have a decent line bringing it back. If the distance updates slower or starts gaining, then the craft could be oriented to return, but not in a direct path. It may be flying back, but more of an angular direction instead of straighter path.

It's a good idea to experiment with the craft to learn orientation without a visual guide. Even if the craft is only 100m from you, learning these tricks can help save from losing the drone. MP is robust enough that if the app disconnects, you can still use the RC data to get it back. If not, there is always the RTH button as a fail safe. Check those settings in the app as well. Be sure your RTH altitude is high enough for buildings and the terrain.

thanos.szs Posted at 2018-7-14 21:13
Already got it. I asked the owner to let me climb on the roof from the other side and retrieved it with a long hooked stick very very carefully to avoid breaking the tiles. Thank god it didn't rain during the night. All is well now and I'll check it the functions today.

lol well glad you got it and the owner was so nice. I have seen videos of rescues using another drone so thought maybe you used another drone to fish it off the roof.

It looks pretty much likely you lost transmission signal, the envoirment you are flying in has the potential to cause much interference.
Your aircraft landed on low battery, I believe you still had RC signal because if that was lost aircraft would have RTH after 3 seconds, which obviously didn’t happen, and also your log would have shown this.

I believe the day before your aircraft returned because you lost RC.

If you lose transmission, the best option you have if you have lost sight or coordination, is to just switch off RC and aircraft will RTH .

miketmtpro Posted at 2018-7-15 01:10
Here's what you do. If you have the craft out and get disconnected, DO NOT yaw, turn etc. Stop. Look at the last map direction indicator. When my app has crashed, the direction stays as it was. Only the ap is down and not updating. STOP and now look at the Remote distance number.

That should be the last known direction and craft orientation. If it looked as if it was pointed away, go ahead and push the R stick forward look at the distance telemetry. You want the craft distance to close from your location. Number should go down. If it goes up, push the stick the opposite direction.

Yes. Very clever that with the distance. Didn' t think of it. Thanks.

hallmark007 Posted at 2018-7-15 04:22
It looks pretty much likely you lost transmission signal, the envoirment you are flying in has the potential to cause much interference.
Your aircraft landed on low battery, I believe you still had RC signal because if that was lost aircraft would have RTH after 3 seconds, which obviously didn’t happen, and also your log would have shown this.

My guess is that after take off it had only 5 sats locked. After flying for 30secs it locked 16 and exaclty that moment the app disconnected. That's why it set home point on the roof.

thanos.szs Posted at 2018-7-16 08:45
My guess is that after take off it had only 5 sats locked. After flying for 30secs it locked 16 and exaclty that moment the app disconnected. That's why it set home point on the roof.

Don’t think so, homepoint recordedat 39 seconds, 95 ft altitude only three feet from home distance .

hallmark007 Posted at 2018-7-16 08:54
Don’t think so, homepoint recordedat 39 seconds, 95 ft altitude only three feet from home distance .

Why? When the homepoint was recorded at 39s the drone was already on the air. Up to this sec it didn't have any data to calc the HP distance so it set 0 to that column. When the sats locked at :39 it started counting the home distance which by then was way different than my real position.

thanos.szs Posted at 2018-7-16 11:59
Why? When the homepoint was recorded at 39s the drone was already on the air. Up to this sec it didn't have any data to calc the HP distance so it set 0 to that column. When the sats locked at :39 it started counting the home distance which by then was way different than my real position.

Upload your logs to here and I will explain. Those airdata logs show very little detail.
Just click on link and follow instructions come back here and post your link.

http://www.phantomhelp.com/LogViewer/Upload/

hallmark007 Posted at 2018-7-16 12:08
Upload your logs to here and I will explain. Those airdata logs show very little detail.
Just click on link and follow instructions come back here and post your link.

Ok let's see if this will work.

http://www.phantomhelp.com/LogViewer/2SUFYL21X3O5XAMSI0BK/

I had a ton of disconnects when I first got my MA. Here is how I fixed it and I've never had a disconnect since. I threw away all the little crap cables that came with the MA. Another thing, ALWAYS be sure you landing feet are set (down) before take off too.