Bell 47G-3B-2 (SOLOY) N7039J

Summary

On 6 January 1983 at about 16:45 local time, a Bell 47G-3B-2 (SOLOY) registered N7039J, operated by Mark W. Duffy, was involved in an accident near Great Falls, Montana, United States. 2 people were on board and nobody was injured. The aircraft was destroyed. No probable cause statement is available for this record.

Date

6 January 1983 at 16:45

Classification

Accident

Location

Great Falls, Montana, United States

Coordinates

Not recorded

Aircraft

Bell 47G-3B-2 (SOLOY)

Registration

N7039J

Category

Helicopter

Engines

1

Operator

Mark W. Duffy

Operating rule

Part 91: General Aviation

Purpose of flight

Public Use

Phase of flight

Not recorded

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

DEN83LA046

Nobody was injured.

The NTSB has not published a probable cause for this record. No probable cause statement is present in the source data.

Nothing about the cause is stated here that is not in the source record.

Read the full NTSB narrative

WHILE MANEUVERING AT LOW ALTITUDE IN SEARCH OF ANIMALS, THE PILOT EXPERIENCED A SEVERE VIBRATION THROUGH THE FLIGHT CONTROLS. THE HELICOPTER BEGAN AN UNCONTROLLED DESCENT AND ATTEMPTS TO STOP THE DESCENT BY USING THE COLLECTIVE WERE UNSUCCESSFUL. THE HELICOPTER CONTACTED THE GROUND AND WAS SUBSTANTIALLY DAMAGED. AN EXAMINATION REVEALED THAT AN AN-320-5 NUT HAD COME OFF OF A PIN ON THE ROTATING SWASHPLATE RING. THE PURPOSE OF THIS NUT WAS TO SECURE THE LINK AND SCISSORS TO THE SWASHPLATE PIN. WITH THE NUT OFF, A LOSS OF CONTINUITY OCCURRED IN THE ROTATING CONTROLS OF ONE MAIN ROTOR BLADE. A COTTER PIN WAS REQUIRED TO SECURE THE NUT. THE ABSENCE OF A COTTER PIN WOULD HAVE ALLOWED THE NUT TO EVENTUALLY WORK ITS WAY OFF. THE HELICOPTER HAD BEEN OPERATED ABOUT 26 HRS SINCE A 1200 HR INSPECTION HAD BEEN PERFORMED. DURING THAT INSPECTION, THE ABOVE MENTIONED PARTS AND COMPONENTS HAD BEEN REMOVED, INSPECTED AND REINSTALLED.

Quoted verbatim from the NTSB record.