Aerospatiale AS350BA N189ND

Summary

On 3 October 2000 at about 21:30 local time, a Aerospatiale AS350BA registered N189ND was involved in an accident near El Cajon, California, United States. 2 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

3 October 2000 at 21:30

Classification

Accident

Location

El Cajon, California, United States

Nearest airport

Gillespie Field Airport (SEE)

Coordinates

32.7893, -116.9592

Aircraft

Aerospatiale AS350BA

Registration

N189ND

Category

Helicopter

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Positioning

Phase of flight

Not recorded

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

LAX01LA009

Nobody was injured.

Improper torquing procedure of the aft tail rotor drive shaft coupling by maintenance personnel after tracking the tail rotor.

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

Read the full NTSB narrative

While positioning the helicopter from the ground to a storage cart, the pilot lost directional, made a hard landing, and the tail boom struck the ground. Prior to the loss of directional control, the pilot saw something depart the tail section. He attributed the loss of directional control to a tail rotor failure. He initiated an autorotation over the landing cart. He maneuvered away from the cart in order to land on the ground and prevent a partial landing on the cart. The on-scene investigation revealed the aft drive shaft coupling was detached from the tail rotor drive shaft. Three bolts retain the coupling. One bolt was found attached to the coupling, another bolt was found on the ground, and the third bolt, and two of the retaining nuts, were not located. Neither bolt exhibited stripped threads or deformation. The last maintenance performed on the helicopter was by the previous owner. A track and balance of the tail rotor system was performed about 48 flight hours prior to the accident. According to the manufacturer's maintenance instructions, the balancing is accomplished by placement of washers under the nuts that are used to secure the bolts that attach to the aft drive shaft coupling. These are the same nuts that were not located at the accident site. Maintenance instructions also specify that the bolts in this area should be checked for proper torque and safety after an inspection.

Quoted verbatim from the NTSB record.