Primary finding
Probable cause
The pilot’s failure to maintain clearance from the unmanned aircraft system during takeoff.
Investigator assessment
Analysis narrative
After the pilot completed the preflight of the quadcopter style unmanned aircraft system (UAS), he backed away from the UAS and initiated takeoff. As the UAS began to take off, the pilot walked back towards the UAS to retrieve old batteries. As he bent over to pick up the batteries, he sensed the UAS was too close to him, and he raised his hands to shield his face. The UAS rotor blade contacted his hand resulting in a serious injury. The operator also reported that one of the rotor blades needed to be replaced.