NTSB Identification: ATL89DLT03.
The docket is stored on NTSB microfiche number 41845.
Accident occurred Friday, May 12, 1989 in SHELBYVILLE, TN
Probable Cause Approval Date: 06/30/1992
Aircraft: BELL 47, registration: N908B
Injuries: 1 Uninjured.

INVESTIGATION REVEALED THAT THE HELICOPTER WAS ENGAGED IN AERIAL APPLICATION. DURING A PROCEDURE TURN AROUND THERE WAS A LOUD EXPLOSIVE NOISE & ENGINE RPM EXCEEDED ROTOR RPM. THE PILOT REDUCED THE THROTTLE & TRIED TO ENTER AN AUTOROTATION. ROTOR RPM HAD DECAYED & A HARD LANDING RESULTED. MOST PROBABLE CAUSE FOR THE LOSS OF ROTOR RPM WAS A DISCONNECT BETWEEN THE ENGINE & THE MAIN ROTOR FOR UNKNOWN REASONS.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

FAILURE IN THE ROTOR DRIVE SYSTEM FOR UNKNOWN REASONS. CONTRIBUTING TO THE ACCIDENT WAS THE PILOT'S INABILITY TO PERFORM AN AUTOROTATION.

Index for May1989 | Index of months