Primary finding
Probable cause
The remote pilot’s in-flight loss of control of the unmanned aircraft due to GPS signal fluctuations, which resulted in a collision with, and serious injury to, a person assisting the operation.
Investigator assessment
Analysis narrative
The remote pilot reported that the unmanned aircraft system (UAS) was landing and had reached the designated landing spot and descent height just before the accident. When the UAS was about 1 foot above the ground, the aircraft flew sideways about 30 ft and struck a person assisting with the operation. That individual sustained a broken shoulder. The unmanned aircraft sustained damage to one rotor blade and to the onboard radar assembly; both were replaced. A review of the available flight logs for the UAS indicated that as the aircraft was landing, the number of available GPS satellites decreased. This was accompanied by frequent signal fluctuations. The UAS subsequently calculated a position deviation that it attempted to resolve by repositioning itself.
Source record
Factual narrative
On August 7, 2024, about 1510 eastern daylight time, an XAG P100 Pro UAS, N268MQ, sustained minor damage when it was involved in an accident near Francesville, Indiana. An individual was seriously injured after being struck by the unmanned aircraft. The UAS was operated as a Title 14 Code of Federal Regulations Part 137 agricultural flight. The remote pilot reported that the unmanned aircraft was landing and had reached the landing spot and descent height. However, when it was about 1 foot above the ground, the aircraft flew sideways about 30 ft and struck a person who was assisting with the operation. That individual sustained a broken shoulder. The unmanned aircraft sustained damage to one rotor blade and to the onboard radar assembly; both were replaced. A review of the available flight logs for the UAS indicated that as the aircraft was landing, the number of available GPS satellites decreased , which was accompanied by frequent fluctuations and unstable accuracy. The UAS subsequently calculated a position deviation that it attempted to resolve by repositioning itself. The remote pilot stated that, as a result of this accident, they are now putting a physical barrier between ground personnel and the UAS during takeoff and landing to minimize hazards during those phases of flight.