Primary finding
Probable cause
The student pilot’s failure to maintain lateral control and terrain clearance while hovering, and the flight instructor’s delayed remedial action which resulted in a dynamic rollover.
Investigator assessment
Analysis narrative
The flight instructor of the helicopter reported that, while conducting hover training about five ft above ground level, with the student pilot at the flight control, the helicopter began drifting to the right and the right skid contacted the ground. The helicopter subsequently exceeded the critical roll angle and experienced a dynamic rollover to the right. The helicopter sustained substantial damage to the tailboom. The flight instructor reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation.