NTSB Identification: SEA93LA213.
The docket is stored in the Docket Management System (DMS). Please contact Records Management Division
Accident occurred Friday, September 24, 1993 in DETROIT LAKE, OR
Probable Cause Approval Date: 09/13/1994
Aircraft: BELL UH-1B, registration: N70NW
Injuries: 1 Serious.

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

THE AIRCRAFT STRUCK TREES WHILE ATTEMPTING AN AUTOROTATION AFTER AN ENGINE FAILURE. THE PILOT HAD PUNCHED OFF HIS EXTERNAL LOAD AFTER THE POWER LOSS, BUT WAS UNABLE TO SUCCESSFULLY ACCOMPLISH THE AUTOROTATION DUE TO INSUFFICIENT ALTITUDE AND UNSUITABLE TERRAIN. THE ENGINE FAILURE WAS THE RESULT OF THE FATIGUE FRACTURE OF BLADE NUMBER 19 OF THE SECOND STAGE TURBINE ROTOR ASSEMBLY.

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

FAILURE OF A SECOND STAGE TURBINE WHEEL TOO LOW FOR A SUCCESSFUL AUTOROTATION. FACTORS INCLUDE A TREE IN THE APPROACH PATH.

Full narrative available

Index for Sep1993 | Index of months