What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) Student pilot mismanaged flight controls during performance of a hovering autorotation. Instructor initiated maneuver in a three foot to five foot hover by retarding throttle to idle. The helicopter yawed left and student immediately raised collective pitch control to upper stop resulting in an instantaneous decay of main rotor RPM. The aircraft drifted rapidly to the left in a high rate, uncontrolled descent. The instructor corrected for the left yaw, but he was unable to gain control of the cyclic pitch control before the helicopter impacted the concrete left skid tow and rolled on its left side. The helicopter sustained substantial structural damage to main rotor system, drive train, fuselage, tail boom, and tail rotor. The instructor and student were not injured and exited the aircraft.
As the FAA filed it
(-23) STUDENT PILOT MISMANAGED FLIGHT CONTROLS DURING PERFORMANCE OF A HOVERING AUTOROTATION. INSTRUCTOR INITIATED MANEUVER IN A THREE FOOT TO FIVE FOOT HOVER BY RETARDING THROTTLE TO IDLE. THE HELICOPTER YAWED LEFT AND STUDENT IMMEDIATELY RAISED COLLECTIVE PITCH CONTROL TO UPPER STOP RESULTING IN AN INSTANTANEOUS DECAY OF MAIN ROTOR RPM. THE AIRCRAFT DRIFTED RAPIDLY TO THE LEFT IN A HIGH RATE, UNCONTROLLED DESCENT. THE INSTRUCTOR CORRECTED FOR THE LEFT YAW, BUT HE WAS UNABLE TO GAIN CONTROL OF THE CYCLIC PITCH CONTROL BEFORE THE HELICOPTER IMPACTED THE CONCRETE LEFT SKID TOW AND ROLLED ON ITS LEFT SIDE. THE HELICOPTER SUSTAINED SUBSTANTIAL STRUCTURAL DAMAGE TO MAIN ROTOR SYSTEM, DRIVE TRAIN, FUSELAGE, TAIL BOOM, AND TAIL ROTOR. THE INSTRUCTOR AND STUDENT WERE NOT INJURED AND EXITED THE AIRCRAFT.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.