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"Rc not connected to mobile"

JehH

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Hey there I lost my mini 2 drone mid flight 22 hours after opening it out of the box. The flight data recorder and actual video footage end at the same time this message rc not connected to mobile came up and my connection dropped with zero recovery. I checked cable connection and desperately tried to reconnect and wait for rth. I wasn't far 376 meters and I could see myself in the video seconds before lost connection. No collision or evidence of it. Phone and rc connected fine with 2 different flights that day. Strong battery and signal never dropped below 8 sats. Remote location no interference. I tried to reconnect to no avail then went on the hunt with controller in hand. Rth was set high. I have a strong phone and brand new cable note 20 ultra. Is this normal? If it were a collision would it not flim it? I uploaded a Google drive with the drones footage and flight data recording and the dat. Cheers and thanks Dji - Google Drive
 
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If it really said "RC not connected to the MOBILE" ... you most probably hadn't lost the connection with the Mini2, that would have been "RC not connected to the AIRCRAFT".

All this suggests that your cable came loose either from the mobile or the RC side ... & then the app lost all communication with the RC and stopped the live view & all telemetries... & the flight log recording into your phone.

If all this was the case, your Mini2 would have been left to hover until the low battery RTH automatically was initiated ... don't have a clue how high you had set the RTH height to though ... but if it had a too strong headwind up high back, it might not have made it the full stretch home until the low battery landing was initiated.

By the way ... your Google Drive isn't made public ...
 
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If it really said "RC not connected to the MOBILE" ... you most probably hadn't lost the connection with the Mini2, that would have been "RC not connected to the AIRCRAFT".

All this suggests that your cable came loose either from the mobile or the RC side ... & then the app lost all communication with the RC and stopped the live view & all telemetries... & the flight log recording into your phone.

If all this was the case, your Mini2 would have been left to hover until the low battery RTH automatically was initiated ... don't have a clue how high you had set the RTH height to though ... but if it had a too strong headwind up high back, it might not have made it the full stretch home until the low battery landing was initiated.

By the way ... your Google Drive isn't made public ...
Appreciate the feed back. Very interesting. I had strong battery 86 percent and little to no wind. I flew higher just down stream previous flight. Rth 500 meters and with 15 minutes standing 30 feet from last known GPS with Controller set. No sound or visual but above a river. Sounds like sol to me.
 
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Yup, most likely was still in full control, just no app display. Just needed to initiate RTH with the button on the RC, and unless default settings were changed it should have initiated RTH on its own when battery got low and landed where you took off from.
 
Now when you've made your Google Drive public I could have a look at the mobile device .DAT log you had there ...

It doesn't show any other reason for the lost view in your screen device than what the message said ... "RC not connected to the MOBILE"

You were commanding left roll with a slight input of yaw at roughly 11m above the HP when the log stopped. No abrupt movements was seen in either roll, pitch or yaw before the end. The satellite count & navhealth was sufficient for a stable flight, but was dropping just in the end. Surprisingly you had the failsafe setting at Hover instead of RTH ... doesn't seem to be the right place for that?

You had 86% battery when the log ended & by interpolating out from the earlier consumption the AC drained 1% each 15,7sec ... meaning that the power would have lasted approx 19,8min. before reaching low battery auto land at 10%. But well before that the AC would have low battery RTH ...

So either it's a mystery that the AC didn't low battery Returned To Home ... perhaps the height was set to low (don't have that info in the DAT) & crashed into something on the way back ... or you didn't wait long enough before giving up the hope ... & it actually returned & are waiting on the spot now ... or you continued to command the AC with that roll a bit after the live view disappeared & hit those trees nearby behind the AC ..?

You most likely had RC connection to the AC all the time ... if you only had pushed the RTH it most probably had done exactly that ...

(Click on the chart to make it larger)
1615408906881.png
 
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Now when you've made your Google Drive public I could have a look at the mobile device .DAT log you had there ...

It doesn't show any other reason for the lost view in your screen device than what the message said ... "RC not connected to the MOBILE"

You were commanding left roll with a slight input of yaw at roughly 11m above the HP when the log stopped. No abrupt movements was seen in either roll, pitch or yaw before the end. The satellite count & navhealth was sufficient for a stable flight, but was dropping just in the end. Surprisingly you had the failsafe setting at Hover instead of RTH ... doesn't seem to be the right place for that?

You had 86% battery when the log ended & by interpolating out from the earlier consumption the AC drained 1% each 15,7sec ... meaning that the power would have lasted approx 19,8min. before reaching low battery auto land at 10%. But well before that the AC would have low battery RTH ...

So either it's a mystery that the AC didn't low battery Returned To Home ... perhaps the height was set to low (don't have that info in the DAT) & crashed into something on the way back ... or you didn't wait long enough before giving up the hope ... & it actually returned & are waiting on the spot now ... or you continued to command the AC with that roll a bit after the live view disappeared & hit those trees nearby behind the AC ..?

You most likely had RC connection to the AC all the time ... if you only had pushed the RTH it most probably had done exactly that ...

(Click on the chart to make it larger)
View attachment 125512
Thank you very much for your reply. Very insightful. RtH set to hover was not intentional. I am newbie and I should of read more into lost connections and paid the price thebhard way. RTH was set to 500 meters unfortunately. There was little to no wind but it's a big climb to fly about 1500 feet distance wise back to home. We looked over the area really well. No luck. Time to start saving and take the lesson as it is.
 
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...RTH was set to 500 meters unfortunately. There was little to no wind but it's a big climb to fly...
Wow ... yeah, that was a second major mistake besides having the failsafe set to hover.

If the RTH in the end was initiated by a low battery, it would certainly have drained it dry in order to ascend that high ... my guess is that it didn't made it up to that height before it entered the low battery autoland phase.

Then ... winds at 500m can be A LOT different than were you stood.
 
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Wow ... yeah, that was a second major mistake besides having the failsafe set to hover.

If the RTH in the end was initiated by a low battery, it would certainly have drained it dry in order to ascend that high ... my guess is that it didn't made it up to that height before it entered the low battery autoland phase.

Then ... winds at 500m can be A LOT different than were you stood.
Just thought I'd let you know Dji simply ruled I crashed into the cliff. While I believe the gap behind to be a bit larger than meets the eye I'll take it as a few different lessons learnt in pre flight set up and loss connection protocol and accept their 15% discount.
 
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Just thought I'd let you know Dji simply ruled I crashed into the cliff. While I believe the gap behind to be a bit larger than meets the eye I'll take it as a few different lessons learnt in pre flight set up and loss connection protocol and accept their 15% discount.
That could have been a possible outcome yes ... IF, you by mistake commanded the AC a while after the screen went out ... or IF, the AC was blown into the cliff when it hovered there. But no proof of that can be seen in the log though ...

Firstly ... the message on your screen clearly says RC & mobile --> RC still connected to AC, so if you crashed that wouldn't be the most logical message... it would say RC & AC.

Secondly ... the log records in 10Hz ... so if a crash would have been the cause for the disconnect we would have seen signs of sudden large AC movements in Yaw, Pitch & Roll ... but in your log they are steady & doesn't indicate any uncommanded movements at all.

So ... it's strange that DJI give you a speculative reason for this, they usually stay clear from that & just say that the log can't explain what happened.

But as this indeed was a pilot error ... the 15% discount offered by DJI is normal.
 
I could have a look at the mobile device .DAT log you had there ...

It doesn't show any other reason for the lost view in your screen device than what th
Hi Slup, I am going through OLD threads and am wondering how you managed to read the DAT for this one? DatCon then CsvView on the csv perhaps?
 
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Hi Slup, I am going through OLD threads and am wondering how you managed to read the DAT for this one? DatCon then CsvView on the csv perhaps?
Just brought the DAT up in CsvView directly... did it again below.

1705832176267.png
 
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Which version of csvview?
4.2.4 refuses for me with " Can't process a Mini 2 DAT" or similar.
DatCon processed it and CsvView dould read DatCon's csv.
 
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