What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) While in cruise flight, the pilot was unable to maintain altitude and heading. An emergency landing was initiated which resulted in loss of control approximately ten feet above the landing area. (.4) during cruise flight the helicopter suffered a loss of tail rotor authority. The pilot initiated an autorotational landing; however, during the approach he lost all control of the aircraft. An inspection of the tail rotor gearbox after the accident revealed a failure of the 90 degree gearbox. The log books indicated an overhaul 195 hours prior to the accident with no other maintenance on the gearbox noted. An inspection of the helicopter was conducted one month prior to the accident and the helicopter had accumulated about 33 hours since that inspection.
As the FAA filed it
(-23) WHILE IN CRUISE FLIGHT, THE PILOT WAS UNABLE TO MAINTAIN ALTITUDE AND HEADING. AN EMERGENCY LANDING WAS INITIATED WHICH RESULTED IN LOSS OF CONTROL APPROXIMATELY TEN FEET ABOVE THE LANDING AREA. (.4) DURING CRUISE FLIGHT THE HELICOPTER SUFFERED A LOSS OF TAIL ROTOR AUTHORITY. THE PILOT INITIATED AN AUTOROTATIONAL LANDING; HOWEVER, DURING THE APPROACH HE LOST ALL CONTROL OF THE AIRCRAFT. AN INSPECTION OF THE TAIL ROTOR GEARBOX AFTER THE ACCIDENT REVEALED A FAILURE OF THE 90 DEGREE GEARBOX. THE LOG BOOKS INDICATED AN OVERHAUL 195 HOURS PRIOR TO THE ACCIDENT WITH NO OTHER MAINTENANCE ON THE GEARBOX NOTED. AN INSPECTION OF THE HELICOPTER WAS CONDUCTED ONE MONTH PRIOR TO THE ACCIDENT AND THE HELICOPTER HAD ACCUMULATED ABOUT 33 HOURS SINCE THAT INSPECTION.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.
Other reports on N9739C · 1
Matched to the same aircraft by N-number and date.