What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
While conducting a part 91 ride with one passenger the pilot notified Flying W UNICOM of throttle failure and that the RPM was stuck at a high power setting. For approximately 15 minutes 3 other qualified helicopter pilots rendered assistance, advice and suggestions over the UNICOM frequency. The local police, fire and EMS was alerted and was in position adjacent to the intended runway for landing. The pilot elected to perform an autorotation from approximately 1000' AGL to runway 1. The initial segment of the autorotation appeared normal to aviation witnesses. At approximately 500' AGL however the helicopter descended vertically at a high rate with noticeably low rotor RPM and impacted trees and brush in a ravine approximately 200' short of the intended runway.
As the FAA filed it
WHILE CONDUCTING A PART 91 RIDE WITH ONE PASSENGER THE PILOT NOTIFIED FLYING W UNICOM OF THROTTLE FAILURE AND THAT THE RPM WAS STUCK AT A HIGH POWER SETTING. FOR APPROXIMATELY 15 MINUTES 3 OTHER QUALIFIED HELICOPTER PILOTS RENDERED ASSISTANCE, ADVICE AND SUGGESTIONS OVER THE UNICOM FREQUENCY. THE LOCAL POLICE, FIRE AND EMS WAS ALERTED AND WAS IN POSITION ADJACENT TO THE INTENDED RUNWAY FOR LANDING. THE PILOT ELECTED TO PERFORM AN AUTOROTATION FROM APPROXIMATELY 1000' AGL TO RUNWAY 1. THE INITIAL SEGMENT OF THE AUTOROTATION APPEARED NORMAL TO AVIATION WITNESSES. AT APPROXIMATELY 500' AGL HOWEVER THE HELICOPTER DESCENDED VERTICALLY AT A HIGH RATE WITH NOTICEABLY LOW ROTOR RPM AND IMPACTED TREES AND BRUSH IN A RAVINE APPROXIMATELY 200' SHORT OF THE INTENDED RUNWAY.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.