lost connection - didn't RTH but just hovered in place

[Subnet]

Newbie here and first time creating a thread

For starters, I've flown a number of times where trees eventually get in the way when my Mini 2 is quite far out, and I lose connection and RTH works perfectly.

This past weekend, after flying out over the ocean for over a mile (over 1,600 meters), I decided to go in a different direction, went about 60m high and proceeded to fly 'down' the beach, parallel to the water. I was standing on the beach and there was absolutely nothing in the way, and when I was about 400m away from me, I lost connection. Strange but no big deal I thought, but this time RTH didn't engage, and the drone just sat their hovering.

After about 6 minutes, I decided that it wasn't coming back and I proceeded to walk towards it. It wasn't until I was less than 100m away, it finally reconnected and I could land.

Has anyone had this happen before where RTH didn't work correctly? Any thoughts? I wonder if when the battery would have gotten low enough it might have triggered auto RTH?

I'm glad I could walk to it vs. having it just sit there hovering over the Pacific...

 

[Thomas B]

Welcome to the forum from the deserts of Arizona! Enjoy.

what other equipment and software were you using at the time?

 

[Chanc3]

Check your app settings, under meenu go to safety tab then scroll down to advanced safety settings. Under signal lost, you can set what you want your mini 2 to do in case of rc signal loss. I highly suggest that you adjust the setting accordingly depending on where you are flying. This is one of the things that I check right after take off.

 

[Meta4]

I lost connection. Strange but no big deal I thought, but this time RTH didn't engage, and the drone just sat their hovering.

Two possible explanations.
1. You only lost downlink but not the signal from controller to the drone.
This sometimes happens, with the signal on the edge of being lost, but not quite.
If that was the case, you would still have had control and could have brought the drone back or initiated RTH.

2. You lost signal, but had changed the default loss of signal action to Hover.
But almost no-one ever does this as there are very few situations where this is useful.
And it won't change to this setting by itself.

Your flight data might help work out what actually happened.

Has anyone had this happen before where RTH didn't work correctly? Any thoughts? I wonder if when the battery would have gotten low enough it might have triggered auto RTH?

Low battery failsafe should have worked normally.
Or switching off the controller should have triggered Failsafe RTH.

A little testing in a large open area would be a good idea.
Fly out 100 ft and switch off the controller.
That should demonstrate what happens when signal is lost.

 

[Mike Mas]

Looks like your fail-safe was set to "Hover In Place" rather than Return Home. Easy fix in your Prefs! Not sure why you would run out of rang at that short distance unless the band was packed with noise but it does happen. Try flying it at another location for a safety test somewhere dry LOL

Mike

 

[Subnet]

Welcome to the forum from the deserts of Arizona! Enjoy.

what other equipment and software were you using at the time?

Just the DJI app on my iPhone, connected to the standard controller - nothing else

Check your app settings, under meenu go to safety tab then scroll down to advanced safety settings. Under signal lost, you can set what you want your mini 2 to do in case of rc signal loss. I highly suggest that you adjust the setting accordingly depending on where you are flying. This is one of the things that I check right after take off.

Was already set for RTH and not hover. The RTH worked previously when losing signal.

Two possible explanations.
1. You only lost downlink but not the signal from controller to the drone.
This sometimes happens, with the signal on the edge of being lost, but not quite.
If that was the case, you would still have had control and could have brought the drone back or initiated RTH.

2. You lost signal, but had changed the default loss of signal action to Hover.
But almost no-one ever does this as there are very few situations where this is useful.
And it won't change to this setting by itself.

Your flight data might help work out what actually happened.

Low battery failsafe should have worked normally.
Or switching off the controller should have triffered Failsafe RTH.

A little testing in a large open area would be a good idea.
Fly out 100 ft and switch off the controller.
That should demonstrate what happens when signal is lost.

First thing I verified was that I hadn't changed it to hover, and I didn't. It was still set to RTH.

I was thinking about testing by switching off the controller - thanks - will do just that!

Looks like your fail-safe was set to "Hover In Place" rather than Return Home. Easy fix in your Prefs! Not sure why you would run out of rang at that short distance unless the band was packed with noise but it does happen. Try flying it at another location for a safety test somewhere dry LOL

Mike

Nope - was set to RTH on the first day I got it and I didn't change it...


Thanks for all the replies everyone - sounds like just a weird thing and nothing 'normal'. I'll continue to fly and will see if it ever happens again, where it might be hardware related.

 

[Meta4]

Thanks for all the replies everyone - sounds like just a weird thing and nothing 'normal'. I'll continue to fly and will see if it ever happens again, where it might be hardware related.

Your flight data should have the explanation for the incident.

Go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record from your phone or tablet.
That will give you a report of the flight.
Come back and post a link to the report it gives you (even if teh report looks empty).
Or .. just post the txt file here.

 

[Subnet]

Your flight data should have the explanation for the incident.

Go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record from your phone or tablet.
That will give you a report of the flight.
Come back and post a link to the report it gives you (even if teh report looks empty).
Or .. just post the txt file here.

Thanks Thomas!

I found 2 flight log's for that day. The first was 'blank', but the second had some info including a 'speed error'. Here is the link to the second one.

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

if that's not the correct one, here's a link to the first log: DJI Flight Log Viewer - PhantomHelp.com

 

[Subnet]

Two possible explanations.
1. You only lost downlink but not the signal from controller to the drone.
This sometimes happens, with the signal on the edge of being lost, but not quite.
If that was the case, you would still have had control and could have brought the drone back or initiated RTH.

2. You lost signal, but had changed the default loss of signal action to Hover.
But almost no-one ever does this as there are very few situations where this is useful.
And it won't change to this setting by itself.

Your flight data might help work out what actually happened.

Low battery failsafe should have worked normally.
Or switching off the controller should have triggered Failsafe RTH.

A little testing in a large open area would be a good idea.
Fly out 100 ft and switch off the controller.
That should demonstrate what happens when signal is lost.

wanted to update - I did a test today where I disconnected the lightening cable from my iPhone to disconnect the RC from the Mini2. It sat there, stable, until the battery low warning was triggered and then it did return to home correctly.

When I had this problem on the beach, it hadn't reached the low battery stage yet, so I'm assuming it would have RTH just fine if I had waited.

 

[Meta4]

wanted to update - I did a test today where I disconnected the lightening cable from my iPhone to disconnect the RC from the Mini2. It sat there, stable, until the battery low warning was triggered and then it did return to home correctly.

Pulling the cable, just takes the phone out, but you still have full control signal between the controller and drone.
You need to switch the controller off to see if it initiates Failsafe RTH, which is different from Low Battery RTH..
ps .. make surethe drone is out >66 ft when you do the test.

 

[Meta4]

Thanks Thomas!

I found 2 flight log's for that day. The first was 'blank', but the second had some info including a 'speed error'. Here is the link to the second one.

The second flight of those two shows that the first possible cause mentioned in post #4 is the explanation for the incident.
At 6:21.7 seconds the downlink was lost and didn't return until 5:27.4 later.
There's nothing to explain why this happened, but you should have had full control during that time.

 

[Subnet]

The second flight of those two shows that the first possible cause mentioned in post #4 is the explanation for the incident.
At 6:21.7 seconds the downlink was lost and didn't return until 5:27.4 later.
There's nothing to explain why this happened, but you should have had full control during that time.

bizarre - again it was completely 'flat' on the beach, nothing in the way, not that far away... I feel a lot better now knowing that it would at least RTH when the battery reached a low level - thanks for checking!

 

[Meta4]

I feel a lot better now knowing that it would at least RTH when the battery reached a low level - thanks for checking!

It would also have returned if you switched off the controller causing the signal to be lost.
Or you should have been able to fly it back manually.
The data indicates that the uplink was not lost and the drone was just sitting there for 5.5 minutes waiting for you to do someting.

 

[MAvic_South_Oz]

The drone wasn't facing the sun when it entered RTH mode, was it ?
The sun into the sensors is often picked up as an obstacle.
I've had it happen briefly in flight, but never if RTH was used (rarely use it).

If it happens again and the sun might be to blame, try turning 90 degrees to the sun and pitching it home sideways, or face away and reverse

 

[Meta4]

The drone wasn't facing the sun when it entered RTH mode, was it ?
The sun into the sensors is often picked up as an obstacle.
I've had it happen briefly in flight, but never if RTH was used (rarely use it).

If it happens again and the sun might be to blame, try turning 90 degrees to the sun and pitching it home sideways, or face away and reverse

The issue has nothing to with obstacle avoidance or sensors.
The drone lost downlink.

 

[MAvic_South_Oz]

The issue has nothing to with obstacle avoidance or sensors.
The drone lost downlink.

Whoops, misread that, thought it had tried RTH.
Downlink loss does seem likely.
Hopefully just a blip that won't crop up too often.

 

[Meta4]

Downlink loss does seem likely.

It's not that it seems likely, it's what happened.
The data had a gap of 5:27.4 and included a message: Downlink data connection lost for 327.4 seconds

 

[Subnet]

It would also have returned if you switched off the controller causing the signal to be lost.
Or you should have been able to fly it back manually.
The data indicates that the uplink was not lost and the drone was just sitting there for 5.5 minutes waiting for you to do someting.

Being a fairly new drone pilot/owner, I didn't know I could have just reversed course back to me and was totally relying on the DJI Fly app on my iPhone. It was a 'oh crap what kind of trouble am I in moment', so that's why I started walking towards it after waiting for the RTH to kick in (again it didn't). Still am surprised it didn't re-acquire the signal until I was very close to it.

Anyhoo, I know a lot more for the next time, if there ever is a next time!

 

[Repaid1]

Being a fairly new drone pilot/owner, I didn't know I could have just reversed course back to me and was totally relying on the DJI Fly app on my iPhone. It was a 'oh crap what kind of trouble am I in moment', so that's why I started walking towards it after waiting for the RTH to kick in (again it didn't). Still am surprised it didn't re-acquire the signal until I was very close to it.

Anyhoo, I know a lot more for the next time, if there ever is a next time!

Don't trust your eyes (as a new flier) or the App, bite the bullet and let RTH work as designed. App crashes are no reason to think you have lost control..press the RTH button on remote or just shut it off as mentioned. It's better to have it home. I don't remember the default on Smart return to home on battery in app if it resets, but your wasting valuable time and if flying into the wind home, you might not make it with the default power. Best to just trust your aircraft and tell it to RTH when first confused or lost...when it starts beeping it means it heard you and it is doing so, you can always cancel it if needed once you get it sorted.

 

[mmoguls]

A possibility not mentioned here is taking off prior to getting a GPS lock. This will not allow a return to home as no home point was recorded. In this case if your signal is lost it will hover in place, no matter what your settings are...