Primary finding
Probable cause
The flight instructor’s delayed remedial action while providing hover instruction in gusting wind conditions, which resulted in dynamic roll-over.
Investigator assessment
Analysis narrative
According to the flight instructor in the skid-equipped helicopter, he was teaching the student to hover over an asphalt helipad. He reported that he transferred the flight controls to the student and directed the student to maintain a stable hover. The nose pitched down, and a right lateral drift occurred. The flight instructor immediately grabbed the flight controls, but the front of the right skid contacted the ground. The main rotor blades then struck the ground, and the helicopter rolled onto its right side. The helicopter sustained substantial damage to the tailboom, fuselage, and the main rotor blades. The instructor reported that there were no preaccident mechanical malfunctions or anomalies with the helicopter that would have prevented normal operation. The meteorological aerodrome report at the airport where the accident occurred reported that the wind was 200° at 9 knots, gusting to 18 knots.
Source record
Factual narrative
According to the flight instructor in the skid-equipped helicopter, he was teaching the student to hover over an asphalt helipad. He reported that he transferred the flight controls to the student, directing the student to maintain a stable hover. The flight instructor reported that the nose pitched down and a right lateral drift occurred. He reported that he immediately grabbed the flight controls but the front of the right skid contacted the ground. The main rotor blades then struck the ground and the helicopter rolled onto its right side. The helicopter sustained substantial damage to the tailboom, fuselage, and the main rotor blades. The instructor reported that there were no mechanical malfunctions or anomalies with the helicopter during the flight that would have prevented normal flight operation. The meteorological aerodrome report at the airport where the accident occurred reported that the wind was out of 200° true at 9 knots, gusting to 18 knots.