CHAMBLEE, GA, USA
N57689
AEROSPATIALE AS 350D
AS THE HELICOPTER APPROACHED THE AIRPORT, IT WAS OBSERVED TO PITCH UP & YAW UNCONTROLLABLY. ACCORDING TO WITNESSES, THE ROTOR SYSTEM SLOWED AS THE HELICOPTER DESCENDED TO IMPACT ON A CITY GOLF COURSE. AN INVESTIGATION REVEALED THAT THE MAIN ROTOR SWASHPLATE BEARING HAD FAILED FROM INADEQUATE LUBRICATION. THE STATIONARY SWASHPLATE VENTING HOLE HAD NOT BEEN BLOCKED OFF IN ACCORDANCE WITH AEROSPATIALE SVC BULLETIN #62.02. THE PURPOSE OF THE SVC BULLETIN WAS TO PREVENT LEAKAGE OF THE LUBRICANT. THE SWASHPLATE BEARING HAD BEEN LUBRICATED 249 HRS PRIOR TO THE ACCIDENT. PRIORITY AD 89-21-01 WAS ISSUED TO REDUCE THE LUBRICATION INTERVAL FROM 400 TO 100 HOURS & TO BLOCK THE VENT HOLE IN THE STATIONARY SWASHPLATE. THE FUEL FLOW CONTROL LEVER & FUEL SHUT-OFF CONTROL WERE FOUND IN THE CLOSED POSITION (AS IF THE PLT HAD SHUT DOWN THE ENG BEFORE THE ACDNT).
FAILURE OF THE MAIN ROTOR SWASHPLATE BEARING DUE TO LACK OF LUBRICANT.
Source: NTSB Aviation Accident Database
Aviation Accidents App
In-Depth Access to Aviation Accident Reports
