What happened
During flight training, an instructor and a student pilot were practicing autorotations. The instructor first demonstrated a 360-degree autorotation maneuver, successfully returning the aircraft to an altitude of 600 feet AGL. Following this demonstration, the student attempted the same maneuver.
As the student completed approximately 270 degrees of the turn, the instructor observed that the airspeed had decreased to 40 knots and a high rate of descent had developed. The instructor immediately applied power in an attempt to arrest the descent; however, the helicopter made a hard landing on the right skid.
The investigation
Upon inspection of the aircraft following the ground strike, it was determined that the right skid collapsed. The impact resulted in damage to the right side of the airframe and caused all three rotor blade tips to be bent.