What happened
During a scheduled practice autorotation maneuver, a helicopter experienced a hard landing. The pilot reported that the procedure was intended to be completed to the ground and proceeded without incident until the flare phase. While executing the flare to establish a specific sink rate, the pilot maintained the attitude to gauge the descent. As the aircraft transitioned to a level attitude in an attempt to cushion the touchdown, it experienced a sudden increase in descent speed.
The aircraft subsequently impacted the ground with significant force, resulting in damage to the helicopter. The pilot noted that there were no mechanical failures or malfunctions involving the aircraft or any of its systems prior to the impact.