Incident Overview
A helicopter sustained substantial damage during a practice autorotation maneuver conducted as part of a flight instructor student's training. The pilot-in-command initiated the exercise while the helicopter was in a low-level agricultural turn at approximately 90 feet above ground level (AGL).
Sequence of Events
As the helicopter flared for landing, the collective pitch was applied earlier than appropriate. This caused the rotor rpm to decay, resulting in a high rate of descent at touchdown. The helicopter bounced back into the air and pitched nose-down. Both pilots then applied aft cyclic input, which caused the main rotor blades to contact the fuselage. The impact severed the tail boom from the helicopter.
Damage
The tail boom was completely separated from the airframe due to the rotor blade strike. The extent of other damage is not specified in the source. No information on injuries or fatalities is provided.
Operational Context
The maneuver was performed as part of a flight instructor student's training, with the pilot-in-command conducting the demonstration. No other details about the flight, such as location, date, or helicopter type, are included in the source.