Investigation number
AO-2012-117
Occurrence date
Location
15 km N of Broome Airport
State
Western Australia
Report release date
Report status
Final
Investigation level
Short
Investigation type
Occurrence Investigation
Investigation status
Completed
Aviation occurrence category
Abnormal engine indications
Occurrence class
Accident
Highest injury level
None

On 7 September 2012 at 0930 Western Standard Time, a Robinson R44 Raven II helicopter registered VH-HYR departed Broome airport, Western Australia on a charter flight to a pearl farm, located north of Broome. On board the helicopter were the pilot and three passengers.

Shortly after departing Broome Airport, the pilot reported that the engine and rotor tachometer were indicating that the engine and rotor revolutions per minute were at the upper limit of the operating range. The pilot also advised that the engine and rotor sounded like it was overspeeding.  The pilot switched the governor off and was able to reduce the engine and rotor RPM, however the low RPM light and horn activated. At about 200 feet above ground level and a speed of 60-70 knots, the pilot was unable to re-establish control of the engine RPM, and he elected to perform a precautionary landing on a road. The helicopter landed heavily, and the main rotor severed the tail boom.  All occupants exited the helicopter without injury. 

The reason for the accident was not conclusively established.  However, a malfunction within the governor assembly itself or the right magneto was considered likely.

Aviation Short Investigation Bulletin - Issue 16

Aircraft Details
Manufacturer
Robinson Helicopter Co
Model
R44
Registration
VH-HYR
Serial number
10341
Operation type
Charter
Sector
Helicopter
Departure point
Broome Airport, WA