What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
While conducting a nighttime agricultural application with two aircraft, while the PIC was operating the two Xag P100 pro UAS near a transmission line one of the aircraft unexpectedly stopped its planned mission, climbed to an altitude of more than 150 feet AGL, and then initiated a return-to-home (rth) sequence for reasons that are currently unknown. The second Xag P100 pro was completing its mission and returning a for landing. His attention was focused on ensuring that aircraft landed safely. When he heard the return-to-home notification from the controller assigned to the other aircraft, he immediately looked toward the operating drone and observed that it had climbed well above its expected operating altitude. He picked up the controller in an attempt to intervene; however, the sequence occurred too quickly for recovery. From the time the return-to-home sequence initiated until the aircraft became entangled in the overhead static wire was approximately 20 seconds.
Prior to this event, PIC stated that both aircraft had completed the remainder of the field without incident. Both drones were operating with rtk enabled, and the field had been evaluated during daylight before the nighttime operation
Began.
As the FAA filed it
WHILE CONDUCTING A NIGHTTIME AGRICULTURAL APPLICATION WITH TWO AIRCRAFT, WHILE THE PIC WAS OPERATING THE TWO XAG P100 PRO UAS NEAR A TRANSMISSION LINE ONE OF THE AIRCRAFT UNEXPECTEDLY STOPPED ITS PLANNED MISSION, CLIMBED TO AN ALTITUDE OF MORE THAN 150 FEET AGL, AND THEN INITIATED A RETURN-TO-HOME (RTH) SEQUENCE FOR REASONS THAT ARE CURRENTLY UNKNOWN. THE SECOND XAG P100 PRO WAS COMPLETING ITS MISSION AND RETURNING A FOR LANDING. HIS ATTENTION WAS FOCUSED ON ENSURING THAT AIRCRAFT LANDED SAFELY. WHEN HE HEARD THE RETURN-TO-HOME NOTIFICATION FROM THE CONTROLLER ASSIGNED TO THE OTHER AIRCRAFT, HE IMMEDIATELY LOOKED TOWARD THE OPERATING DRONE AND OBSERVED THAT IT HAD CLIMBED WELL ABOVE ITS EXPECTED OPERATING ALTITUDE. HE PICKED UP THE CONTROLLER IN AN ATTEMPT TO INTERVENE; HOWEVER, THE SEQUENCE OCCURRED TOO QUICKLY FOR RECOVERY. FROM THE TIME THE RETURN-TO-HOME SEQUENCE INITIATED UNTIL THE AIRCRAFT BECAME ENTANGLED IN THE OVERHEAD STATIC WIRE WAS APPROXIMATELY 20 SECONDS.
PRIOR TO THIS EVENT, PIC STATED THAT BOTH AIRCRAFT HAD COMPLETED THE REMAINDER OF THE FIELD WITHOUT INCIDENT. BOTH DRONES WERE OPERATING WITH RTK ENABLED, AND THE FIELD HAD BEEN EVALUATED DURING DAYLIGHT BEFORE THE NIGHTTIME OPERATION
BEGAN.