Prior to flight, Karma pilots must select flight mode. No GPS or GPS. Once you launch, you can not change modes. I calibrated my drone after selecting to use GPS. Auto takeoff was normal: I hovered 20’ in the air prior to starting a filming run alone the shore line. Within one minute of launch drone climbed and sped out to sea at full speed. Controller reported out “no GPS.” Drone did not return to launch location. Drone did not respond to commands. Drone reported that it was doing an emergency landing. Was lost at sea. Total loss. HAS ANYONE EXPERIENCED LOSS OF CONTROL?