Part 107 UAS pilot reported they were concluding an autonomous flight mission when the UAS veered away from the landing spot; resulting in a fly away. The UAS was lost and unrecoverable.

Narrative

On Day 0; I took the Teal 2 unit out to perform a test flight after repair work had been completed. I had flown a previous mission with this craft previously and the support team decided we could get better results by changing a few settings. I performed some basic manual maneuvers in position mode (pitch forward/back; bank right/left; yaw and figure 8) and all systems were performing well. I landed the craft; loaded the mission on the ground station; and launched the autonomous flight. The entire flight gave no reasons for concern. At the final step of the mission; where the drone is returning to its landing spot; the drone veered about 5 feet to the left (altitude was approx 50 ft); swung back to the right; and at this point; I issued a command to the drone to return immediately to plan. When I pressed the button; instead of heading towards its landing position; the drone began to climb and move north across our flight area. I hit the 'Return to Home' button several times; which usually will land the craft. When I got no response; I assumed manual control; trying to land the craft. Every stick input caused the drone to react more erratically. I considered pressing the Emergency Stop button; but the drone was at approximately 150 feet; traveling quickly; and went beyond VLOS when the drone flew around the northwest corner of the building. I was very concerned that causing the drone to fall at this height and speed significantly increased the chances of bodily harm or damage. As soon as the visual feed to the ground station was lost; I reported it to my superiors; pulled all telemetry information from the drone; and have been searching in a grid pattern with approximately 6 other people. Flight logs do show that the GPS system malfunctioned. All attempts to locate the drone by its remote ID tag and last known coordinates have not produced the system.