Wirestrike involving Robinson R22, VH-HRL, 63 km west of Blackall Airport, Queensland, on 27 July 2016

What happened

On 27 July 2016, at about 0930 Eastern Standard Time (EST), the pilot of a Robinson R22 Beta helicopter, registered VH-HRL (HRL), completed mustering operations at a property about 33 km south of Blackall, Queensland. The helicopter then departed from the property on a ferry flight and tracked towards the pilot’s home about 110 km to the west-northwest. The pilot was the sole occupant of the helicopter.

At about 1002, the pilot’s GPS tracker indicated that the helicopter had stopped moving, about 41 km from its destination and on the helicopter’s direct track. The helicopter had struck a powerline and subsequently collided with terrain. At about 1030, a local landowner notified the energy provider of a power outage. Two line workers from the energy provider later departed from Blackall to determine the source of the power outage.

At about 1500, while inspecting the powerlines in the area, the line workers located the wreckage of HRL. The windshield and right skid of the helicopter had struck the single wire, which was strung east-west across a cleared area, 4.8 m above the ground. The first point of impact of the helicopter was about 31 m beyond the powerline and it then collided with the ground inverted about 18 m further away. During that impact, it appeared that the pilot’s seatbelt sheared through and the pilot was ejected from the helicopter sustaining serious injuries. The wire had been stretched about 30 m, two power poles broke off and another two were pulled out of the ground. The helicopter was destroyed (Figure 1).

The line workers called emergency services using a satellite phone, and remained with the pilot until police and paramedics arrived at about 1700.

Figure 1: Accident site showing damage to VH-HRL

Source: Queensland Police

Accident site

The helicopter struck the powerline in a clearing, mid-span between two power poles about 250 to 300 m apart. The helicopter was travelling across the direction of the powerline.

An aircraft warning marker may be installed on an overhead cable or its supporting structures to warn pilots of their presence. The powerline struck in this incident was not, and was not required to be, marked with aircraft warning markers according to the relevant Australian Standard (AS3891.1).

Based on the forward speed indicated by the distance of the wreckage from the wires, and the marks left in the ground by the helicopter main rotor blades, the helicopter engine was probably producing power at the time it struck the wire.

ATSB comment

Due to the injuries sustained in the accident, the pilot was unable to recall the event or provide any comments for the investigation.

Safety message

Low-level flight carries an increased risk of striking hazards, such as powerlines, many of which are difficult to see in flight. The ability of pilots to detect powerlines depends on many factors, including the physical characteristics of the powerline (such as the spacing of power poles and the orientation of the wire), prevailing weather and light conditions, and the nature of surrounding terrain and vegetation.

Aviation Short Investigations Bulletin - Issue 53