Accident Sequence
During a landing approach, the pilot reduced power, and a high sink rate developed. When the pilot attempted to increase power to correct the sink rate, there was no response from the engine or rotor system. Rotor RPM began to diminish, prompting the pilot to lower the collective to regain rotor RPM.
The pilot then decided to perform an autorotation. During the descent, the pilot held the helicopter in a flare until airspeed was exhausted. At approximately 5 feet above ground level (AGL), the helicopter descended vertically and struck the ground with sufficient force to break off the right skid. The impact caused the helicopter to roll onto its right side, and the main rotor blades struck the ground or other surfaces.
Damage
The right skid was broken off, and the helicopter rolled onto its right side, resulting in contact damage to the main rotor blades.
Pilot Actions
The pilot reduced power for landing, which initiated the high sink rate. After the power increase attempt failed and rotor RPM decreased, the pilot lowered the collective to manage RPM and elected to autorotate. The flare was maintained until airspeed was exhausted, but the helicopter descended vertically from a low altitude, leading to ground contact.