Primary finding
Probable cause
The pilot's failure to maintain control of the helicopter while hovering.
Investigator assessment
Analysis narrative
**This report was modified on 4/2/2026. Please see the docket for the original report.** During an evening test flight, the pilot was hovering the experimental amateur-built helicopter just above the ground to track the main rotor blades with light emitting diodes (LEDs) attached to the blade tips to address a main rotor vibration. He stated that he was distracted by the LED lights and lost control of the helicopter and that “there was nothing wrong with the aircraft.” The helicopter came to rest on its side and sustained substantial damage to the fuselage and empennage. Although the pilot reported no control issues with the helicopter, both the FAA inspector who examined it and the kit manufacturer reported deficiencies with the pilot’s build that would be expected to adversely affect its handling characteristics. According to the kit manufacturer, these included the installation of nonstandard flight control components (from a different helicopter make and model) and other modifications from the original design. However, the extent to which the pilot’s modifications contributed to the outcome could not be determined.