I was mtn surfing at Loveland pass, Colorado, with me DJI FPV,    10 deg,  when the drone kicked out of manual then went completely black.    After a very LONG and stressful few minutes, I did get an image back as the drone was returning home, however neither the drone or goggle video show the return flight.       It's possible that a ridge cut off the signal, but that doesn't explain the total blackout.   I got a "No SD" error.        I did get video back as it was landing.    Not a fun time, but DJI saved the day.  I thought it was gone forever.      I'm sending everything  in to get it checked out.      Anyone ever see this?  If so, what was the problem?

When I was filming in the sand dunes it happened to me. I flew down in a depression surrounded by sand dunes away from me and everything went black. Same as you after some stressful time passed all the sudden I got it back as the drone was returning. No video of the event. It never happened again. That was about a year or so ago.

Hi there. Thank you for reaching out and we do apologize for this experience. We're sorry to know that you came up with a decision to send the unit to us. Rest assured that once your unit arrives at our repair facility, we will initiate proper diagnostics on the unit to distinguish the main issue caused by the said experience. We will keep you updated via email once your unit arrives at our facility. If you need help on your case or anything else, please don't hesitate to reach us. Thank you for your understanding and support.  

When flying in the mountains and canyons,  you need to be careful to always have the drone in direct line of site to avoid a sudden loss of signal.  RF signal doesn't like traveling through mountain.