NTSB Identification: FTW88LA152.
The docket is stored on NTSB microfiche number 38690.
Accident occurred Thursday, August 25, 1988 in SALLISAW, OK
Probable Cause Approval Date: 01/24/1990
Aircraft: Brantly Helicopter B-2B, registration: N2264U
Injuries: 2 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

ACFT EXPERIENCED A HARD LANDING AND ROLLED OVER FOLLOWING A LOSS OF CONTROL IN A HOVER. PLT DELAYED CUTTING THE THROTTLE IN ORDER TO CLEAR A DITCH. INVESTIGATION REVEALED THAT THE TAIL ROTOR DRIVESHAFT COUPLING RETAINING SCREW HAD SEPARATED. THE SEPARATION ALLOWED A DISCONNECT IN THE TAIL ROTOR DRIVESHAFT AND LOSS OF TAIL ROTOR DRIVE. THE REASON FOR THE SCREW FAILURE WAS NOT DETERMINED. ACFT HAD JUST BEEN RETURNED TO SERVICE FOLLOWING EXTENSIVE REPAIRS FOR DAMAGE SUSTAINED IN A PREVIOUS HARD LANDING.

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

ROTOR DRIVE SYSTEM,TAIL ROTOR DRIVE SHAFT COUPLING..FAILURE,TOTAL

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

MAINTENANCE,INSPECTION..INADEQUATE..OTHER MAINTENANCE PERSONNEL

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

ROTOR DRIVE SYSTEM,TAIL ROTOR DRIVE SHAFT..DISCONNECTED


Contributing Factors

TERRAIN CONDITION..DITCH


Contributing Factors

EMERGENCY PROCEDURE..DELAYED..PILOT IN COMMAND

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