I fly my Mavic 2 Pro in evening and shot night scene of bridge. The drone just flew around 100mL & 50mH from my position (RTH).The drone suddenly disconnected from RC. I waited it return to home but no hope. Then I tried to find under the bridge but still not found.

It was absolutely not my fault. My drone was out of warranty. DJI hotline told me no investiagation provided and offered 10% off for replacement.
Is it normal?

Could you upload flight data for more imformation please?(https://www.phantomhelp.com/LogViewer/Upload/)

KN4LGM Posted at 3-18 19:35
Could you upload flight data for more imformation please?(https://www.phantomhelp.com/LogViewer/Upload/)

https://www.phantomhelp.com/LogViewer/K4E2GXMOFF8SFM7E0CV6/
Here you go

ckf_hk Posted at 3-18 19:44
https://www.phantomhelp.com/LogViewer/K4E2GXMOFF8SFM7E0CV6/
Here you go

There's no evidence of a collision in te flight data, it just stops.
This warning that showed up at 0:06.6 might be a clue?
Battery not installed properly. Return to home immediately. Check and re-install battery.

That suggest the battery was not clicked in properly and could have moved enough to make for a poor connection.
The spot where the flight ended doesn't look like a good spot to be searching for wreckage.

Did you not see the warning?

"Forward Obstacle Sensing is not functioning. Ambient Light is too weak." only
But I am sure drone was higher than road sign.
Then, the screen was suddenly grey (disconnected).

It looks like the drone disconnected then after 3 seconds it tried to RTH. For RTH the drone has a preset altitude to achieve before going to the Home Point. If the drone was under the bridge and then tried to reach the Preset altitude, it probably hit the underside of the bridge and fell into the water. Sorry about your loss.

KN4LGM Posted at 3-19 06:47
It looks like the drone disconnected then after 3 seconds it tried to RTH. For RTH the drone has a preset altitude to achieve before going to the Home Point. If the drone was under the bridge and then tried to reach the Preset altitude, it probably hit the underside of the bridge and fell into the water. Sorry about your loss.

However, I am sure the drone was over the bridge.
I guess it idle till low battery and landed somewhere....

A ejected battery is as said earlier totally possible ... you got this message in the beginning of the flight, at 7m height just above your take off spot.



This indicated a battery not properly attached ... then in the end of the flight, when you lost it, you applied a series of full elevator commands with full stick release, pitching the AC max down/up/down ... In the last full elevator you also added full throttle ... I imagine that just were the log ends you probably released the sticks again & that ejected the battery, not the first time I see this happen.

Red=Height
Green=Heading speed
Blue=Pitch angle
Black=Elevator command (forward/backward stick command)
Magenta=Throttle command (ascend/descend stick command)



And yes ... the AC was above the bridge ...

slup Posted at 3-19 08:43
A ejected battery is as said earlier totally possible ... you got this message in the beginning of the flight, at 7m height just above your take off spot.

[view_image]

Ok. Very interesting.