NTSB Identification: DEN00LA069.
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Accident occurred Saturday, April 01, 2000 in HELPER, UT
Probable Cause Approval Date: 03/02/2001
Aircraft: Hawkins & Powers UH-1B, registration: N50330
Injuries: 1 Minor.
NTSB investigators may have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.
As the helicopter approached logging personnel with a 150 foot long line, the pilot heard a 'Shhhh' sound and was advised smoke was coming from the engine. He turned and proceeded down the mountain. The engine then 'quit.' The helicopter collided with heavily wooded steep terrain. The number 1 and 2 bearings were submitted for metallurgical examination. The metallurgical report stated that 'the most likely cause of [the] engine malfunction was degradation of the Position #1 bearing due to insufficient lubrication.' All other damage appeared to be 'secondary.' The accessory carrier assembly was oil flow tested and found to be 'acceptable,' albeit 'near the lower end of requirements.' Debris in the bearing oil strainer was believed to be 'coked oil and epoxy hardener, both unusual for this area of the engine.'
The National Transportation Safety Board determines the probable cause(s) of this accident to be: Total failure of the number 1 bearing due to lack of lubrication, the oil flow being restricted by a foreign object (epoxy hardener). Factors were trees and the unavailability of suitable terrain for a forced landing. Full narrative available
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