Loss of control involving Bell 47G, VH-UAF, Oberon, New South Wales, on 6 November 1990

199000025

Summary

Circumstances:

The helicopter was flying at about 25 knots and a height of about 75 feet, 10 feet to the left of power lines. The passenger was surveying the wires. As the helicopter approached a tree line, the pilot increased collective. However, rotor RPM decayed, and the helicopter descended rapidly, hitting the ground and rolling over.

Significant Factors:

The following factors were considered relevant to the development of the accident

1. The pilot overpitched the main rotor, resulting in a loss of rotor RPM.

2. Insufficient height was available for the rotor RPM to recover before the helicopter struck the ground.

Occurrence summary

Investigation number 199000025
Occurrence date 06/11/1990
Location Oberon
State New South Wales
Report release date 13/07/1992
Report status Final
Investigation type Occurrence Investigation
Investigation status Completed
Mode of transport Aviation
Aviation occurrence category Loss of control
Occurrence class Accident
Highest injury level Minor

Aircraft details

Manufacturer Bell Helicopter Co
Model 47
Registration VH-UAF
Serial number 7546
Sector Helicopter
Operation type Aerial Work
Departure point Oberon NSW
Destination Oberon NSW
Damage Substantial