Spark fly away: lost and looking for answers

Howdy all. I bought a second hand Spark a few months ago and it’s been loads of fun. Recently I had a problem with the remote, so didn’t use it for a while. I planned on getting around to fixing it eventually.

The other day I decided to take it out to try some of the Quickshot features at my mates place using just my phone for control. I fly there as its my old neighbourhood near an open area and we know all the neighbours (we all grew up together and they’re used to us trying new toys out).

I successfully did the ‘Rocket’ shot, then tried to do the ‘Dronie’. On the way back from the Dronie, instead of landing after returning to the home coordinates, the Spark decided to fly off and is now pretty lost.

I uploaded the log data here:

I’ve learned from the logs that the Spark switched to ATTI mode right when it flew off, but I still had 19 satellites on my GPS. Was it a combination of a low battery and returning home from a Quickshot?

I guess I’m just looking for some closure really as I don’t think I’ll ever get it back. What went wrong? I’d love to buy another one, but the thought that I could lose it again is a real put off. What happened on my flight?

Just a theory : phone has limited range, drone switches to Atti mode , wind causes the drone to drift out of range of phone.

Your Nav Health went to zero when the AC switched to ATTI. Return to home is not possible when that occurs. The aircraft most likely auto landed near the last recorded position. The ATTI switch plus the YAW errors may indicate a compass issue, which usually occurs when taking off near a metallic object.
Even under concrete re-bar can cause this.

Hmmm… thanks. There was a big metallic object near where I took off, so that sounds plausible. I’ll take a look for the Spark around the back of the workshops, as there was nothing around the front of them.

Appreciate your help!