The pilot was tasked to spray potato crops in northern Tasmania. On the morning of the accident he left the operator's Devonport base at approximately 0600 ESuT to spray crops in the Sassafras area. He was accompanied by a loader driver with a truck carrying fuel and the chemicals to be used on the day. The pilot was in the habit of taking just enough fuel for the current spraying task, returning to refuel and to load the chemicals as required for the next task.
When the spraying at Sassafras was completed the operation moved to the Kindred area arriving there at about 0800. The pilot completed two runs before departing at about 0915 to spray a crop at Abbotsham.
Abbotsham is a settlement straddling Castra Road, 4 km S of Ulverstone. The crop to be sprayed consisted of two paddocks, 200m apart to the east of Castra Road, at the southern end of the settlement. In accordance with the code of practice for aerial spraying in Tasmania the paddocks were marked with prominently displayed identification numbers and the pilot had been supplied with a map of the area containing the numbers.
The pilot did not arrive at the Abbotsham property but was seen to commence spraying a paddock on the eastern side of Top Gawler Road, 1km W of Abbotsham. The paddock being sprayed was not normally subject to aerial spraying and did not display any identification numbers. The pilot commenced spraying in an east-west direction before turning to spray to the south.
Shortly after turning to the south the helicopter was seen to strike the second of two sets of power lines running east-west across the paddock, approximately 30ft above the crop. The helicopter was seen to tip forward and then level out momentarily, before nosing over and crashing inverted into the crop. Witnesses to the accident immediately notified emergency services, however the pilot had not survived the impact.
The helicopter was destroyed by impact forces but did not catch fire.
Examination of the wreckage determined that the helicopter contained fuel and the engine was delivering power at the time of principle impact. No fault was found with the airframe.
The power line dragged across the top of the skids before snagging on the forward cross beam. This resulted in the helicopter pitching nose down. The tail rotor mechanism was severed from the tail boom by a main rotor blade, most probably when the pilot pulled back on the control column to counter the nose down pitch. This action is supported by the witnesses who saw the helicopter level out momentarily after the power line strike.
The pilot held a commercial pilots license with agricultural ratings for both fixed wing and helicopter operations. He had flown helicopters in excess of 6,000 hours, more than 1,000 of which was in agricultural operations.
The operator advised that this was the pilot's fourth season spraying potato crops in Tasmania and that his demeanor was normal on the morning of the accident. The post mortem examination did not disclose any medical anomaly that may have affected the pilot's ability to carry out the task.
The weather at the time of the accident was fine and mild with no wind and no cloud cover. There were no known visual limitations in the area.
It is not known why the pilot was spraying the wrong crop. He may have mistaken Top Gawler Road for Castra Road because both roads ran in the same direction, but were parallel to each other and were only 1 km apart. However the property on Top Gawler Road was not adjacent to a settlement, nor was it marked in accordance with statutory requirements.
It could not be determined why the pilot failed to sight and avoid the second set of powerlines. Both sets of lines were supported on poles on the brow of a hill adjacent to the crop. The first pole held four powerlines, while the second held three, one of which was supported between and above the other two. The helicopter collided with the upper powerline. It may be that the pilot misjudged the height of the powerline while maneuvering around the crop.
|Date:||19 January 1998||Investigation status:||Completed|
|Location:||1km W Abbotsham|
|Release date:||19 August 1998||Occurrence category:||Accident|
|Report status:||Final||Highest injury level:||Fatal|
|Aircraft manufacturer||Hughes Helicopters|
|Type of operation||Aerial Work|
|Damage to aircraft||Destroyed|
|Departure point||Devonport Tas.|
|Departure time||0600 ESuT|
|Role||Class of licence||Hours on type||Hours total|