Worried, really need help, Phantom went mad

[Steve H]

Hi
I am not an experienced flier, so I ask for your patience as there are aspects of flight data that I do not fully understand.
I'm have flown several successful waypoint missions using Litchi with a Phantom 3 Advanced and have had no problems until the latest one, when I had a heart-stopping problem of the drone suddenly ignoring the waypoints and alternately switching between atti and GPS-atti. This was at a range of about 1 kilometer but luckily still in control range, so I was able to initiate RTH. My big worry is that if it happened while out of control range I could have lost the Phantom which I assume would have hovered until the battery ran down. I have uploaded the csv file to Healthy Drones and Phantomhelp and it shows that at all times there were at least 14 satellites detected. Also the fact that the drone came straight home seems to show that there was no compass error. If anyone can explain the cause of this erratic behavior and hopefully set my mind at rest, I would be very grateful.
My csv file can be seen here:-
HealthyDrones.com - Innovative flight data analysis that matters
or here:- Phantom Log Viewer - PhantomHelp.com
I would also like to show the mission with the waypoints, as this anomaly started exactly at a waypoint, but I do not know how to supply you with the data.

 

[Mark The Droner]

Very odd. I don't know why it would switch to ATTI unless you were switching it to ATTI. Could it be your controller has some sort of defect in the ATTI switch? Could it be you didn't have the controller switch fully in GPS mode?

If it was mine, I'd put a tracker on it.

 

[Steve H]

Very odd. I don't know why it would switch to ATTI unless you were switching it to ATTI. Could it be your controller has some sort of defect in the ATTI switch? Could it be you didn't have the controller switch fully in GPS mode?

If it was mine, I'd put a tracker on it.

Hi Mark the Droner. Thanks for your reply. I think I must have been in full GPS mode for the Litchi waypoint mission start, and I do not think I was touching the switch during the mission. I am wondering whether the AC could have been exposed to some sort of interference which disrupted the GPS signal, causing the drone to revert to ATTI. As I mentioned, the mode was actually alternating between ATTI and GPS-ATTI. Could this behavior be caused by interference? I believe some of the experts on this forum are able to look at the details in the .dat files to determine the cause of this problem.
If so I would love to hear from some of them.
And, yes, my wife is going to buy me a tracker for Christmas.