Bell 47G-4A (SOLOY) N23PH

Summary

On 19 September 1996 at about 17:45 local time, a Bell 47G-4A (SOLOY) registered N23PH was involved in an accident near Belmont, Mississippi, 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

19 September 1996 at 17:45

Classification

Accident

Location

Belmont, Mississippi, United States

Coordinates

34.4991, -88.2010

Aircraft

Bell 47G-4A (SOLOY)

Registration

N23PH

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 137: Agricultural

Purpose of flight

Aerial Application

Phase of flight

Not recorded

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ATL96LA129

1 person had minor injuries.

failure of the aft universal joint of the tail rotor drive shaft, due to inadequate lubrication by company maintenance personnel. A factor relating to the accident was the pilot's delay in discontinuing the flight after noting a progressively worse tail rotor drive vibration.

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

Read the full NTSB narrative

During an aerial application operation, the pilot was making east and west swath runs. He reported that he had dispensed about half of his load, when he noted a vibration in the tail rotor pedals during a turn-around maneuver. He conducted three more swath runs with the vibration becoming progressively worse during each turn-around. Subsequently, during the fourth turn-around, the tail rotor drive was lost when the tail rotor drive shaft aft universal joint failed. Examination of the universal joint revealed a lack of lubricant, and the tail rotor drive shaft was discolored blue. There was no log book entry to indicate that the universal joint had been lubricated in the 150 plus hours of operation since the last inspection. The manufacturer's recommended maintenance practices included lubrication of the universal joint after each 50 hours of operation.

Quoted verbatim from the NTSB record.