Traveled to Switzerland this past weekend and wanted to get some footage at the Ebenalp. We're about 1500m high when I decided to take her up. Before takeoff, controller displayed a message that I needed to calibrate the compass. Did 2 passes at the calibration procedure and got the ok that it was calibrated. Started to take off and hover for a few seconds and proceeded on her flight. Got about 5-8 seconds in to the flight and I notice the controller saying I lost the GPS signal or maybe it was compass. I can't remember because I was already starting to panic because she wasn't responding to any stick inputs. 15-20 seconds pass and she flies away from me. I chase after her and I knew by the direction she went that she was heading straight into the cliff wall behind me. I find her lying on the ground with the battery ejected and the gimbal hanging by its cables. I do have the low-res video from my phone. I can upload it later tonight.