Bell UH-1H N3276T

Summary

On 15 July 2008 at about 21:30 local time, a Bell UH-1H registered N3276T, operated by Leading Edge Aviation, was involved in an accident near Rock Springs, Wyoming, United States. One person was on board and one had minor injuries. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

15 July 2008 at 21:30

Classification

Accident

Location

Rock Springs, Wyoming, United States

Coordinates

41.1131, -109.6567

Aircraft

Bell UH-1H

Registration

N3276T

Category

Helicopter

Engines

1

Operator

Leading Edge Aviation

Operating rule

Part 133: Rotorcraft Ext. Load

Purpose of flight

External Load

Phase of flight

Not recorded

Route

Rock Springs → Unknown

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

LAX08LA230

1 person had minor injuries.

A total loss of engine power due to the failure of the No. 1 bearing for undetermined reasons.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

During an external load operation involving lifting a drill for repositioning, the pilot heard multiple loud reports (compressor stalls) coming from the rear of the helicopter, followed by an adverse yaw. The pilot jettisoned the drill and pointed the helicopter down a hill to avoid nearby ground personnel. The helicopter landed hard on its skids and then rolled onto its left side. During the engine examination investigators noted no movement of the power turbine during the visual examination and metal pieces were found in the exhaust. The compressor turbine leading edge blades and inlet guide vane trailing edges were damaged. Further examination of the engine revealed that the No. 1 bearing and associated hardware showed evidence of over-temperature exposure, but the exact cause for the over-temperature could not be determined. Pieces of bearing cage were found lying loose at the bottom of the reduction gearbox cavity and the ball bearings were grouped to one side and smeared over. While the manufacturer indicated that a bearing cage failure may have initiated the failure of the bearing, the investigation was unable to conclusively determine the cause of the bearing failure.

Quoted verbatim from the NTSB record.