Regional flying has hazards and one is almost invisible to the naked eye – wires.
Wire strikes can affect both fixed wing and rotorcraft, with several notable accidents occurring over the past few years. They often occur when a pilot attempts a low-level flying manoeuvre and does not see – or is unaware of – an electrical wire running through the area.
If contact is made with a wire, it can snap off its posts and become entangled in the propeller or rotor of the aircraft. If an aircraft’s wing hits a wire, the pilot will likely lose control, resulting in a rapid decent and crash. If these outcomes aren’t bad enough, a wire strike can result in electrical shock, possibly leading to the death of those on board.
In October 2023, a Cessna on approach to land at a property in outback South Australia struck wires, resulting in the aircraft crashing to the ground. The crash and ensuing fuel-fed fire led to the death of the pilot and passenger. The fire was so strong that first responders sustained significant burns when attempting to retrieve the occupants from the wreckage.
In its accident report, the ATSB determined the pilot had lost situational awareness on approach and did not see the wires as they came into land. The runway was positioned in a paddock which made the powerlines essentially invisible from the aircraft’s angle of approach. Additionally, the powerline was across the end of the runway, meaning pilots coming into land at that end were more at risk of striking the wire, due to being pre-occupied with the landing.
A Cessna on approach to land at a property in outback South Australia struck wires.
A similar incident earlier in 2023 occurred when a Robinson R44 Raven II helicopter struck a wire while performing low-level mustering activities on a private property in Queensland. In this instance, the pilot was searching for straying cattle when they struck powerlines that were running through a line of trees. The aircraft struck the ground, killing the pilot, and was destroyed in a fuel-fed fire. While the pilot was familiar with the property, it could not be conclusively determined whether they knew of the presence of the powerlines, but still lost situational awareness shortly before the strike.
Joint responsibility
Wire strikes have been a known hazard for a long time, particularly for rural operations, yet accidents are still occurring because of them.
Pilots and landholders have a joint responsibility to ensure safety is the top priority when it comes to conducting agricultural operations. Both parties can take preventative measures to avoid getting caught up in a wire strike.
Nat Nagy, former CEO of the Aerial Application Association of Australia, says preparation is the key for avoiding wire strike accidents. ‘Pilots need to be aware of their surroundings and this includes any buildings, obstacles and power poles in the area,’ he explains.
‘Landowners should provide pilots up-to-date maps of their property prior to commencing work, so they can study it and familiarise themselves with the area they’re dealing with.
‘It should be noted, however, that maps may be out of date, so it’s always a good idea to do a visual survey in addition to studying any maps.’
Improving your chances
Here are the association’s top tips for avoiding a wire strike:
Study the flight area and gather as much information as possible
If a pilot has been contracted to fly on a property, or in areas in which they are unfamiliar with, they need to get to know the area. Pilots should study maps of the intended flight areas, noting where certain landmarks are situated. Even if a pilot has flown in a particular area previously, it is always a good idea to study the area again, in case any changes or installations of new wiring have occurred since the last time they flew there.
Pilots should ask the landowner for as much information about their property as possible. In some instances, the landowner may not know all the answers. This is where pilots need to undertake their own reconnaissance work.
Conduct precautionary searches of the intended flying area
Conducting reconnaissance missions is critical for avoiding a wire strike. Once all major
landmarks are identified on a map, pilots should physically inspect the area. Each landmark, whether it is a building, shed, powerline or pole, will often have a wire attached. Pilots should locatethe wire and trace their location to ensure they know where they lead – and more importantly, where they should stay away from.
The location, position and height of any power lines should be noted and entered into a flight plan. Don’t think this guarantees your safety, however. Of the fatal wire strike accidents recorded by the ATSB in 2012–2022, 43% involved a wire that was known to the pilot. Your alertness must be continual when you are down low in the wire environment. Expect to be very tired when the flight is done.
Make wires stand out from the landscape
Landowners play a vital role in ensuring the safety of the flight crew conducting low-flying operations on their property. To increase the visibility of powerlines, aircraft warning markers can be installed on powerlines to increase their visibility.
Aerial markers are bright in colour and designed to stand out from a bright backdrop, providing pilots better visibility of the wire’s location and position. Powerline markers are proven to reduce the number of wire strike incidents.
Although markers come at a cost to install, several energy companies have incentive programs for landowners to acquire and install them. At the time of writing, Ergon Energy was offering landholders up to 10 Rotamarkers per property, at a cost of $100 each. Other energy companies offer similar incentives to limit the financial burden on individual property owners.
Additionally, pilots flying through valleys or over large bodies of water should take particular caution, as wires over these areas can be extremely difficult to see or predict where they are hanging. The material that wires are made of can expand and retract depending on the temperature of the day, causing a significant variance in their height off the ground or water. Aerial markers help pilots visualise the path of a wire, but they should also take note of the location of any poles to complete the picture.
Commitment to safety
A commitment to safety is crucial for avoiding wire strikes. Before any work is undertaken, expectations should be set and a mutual agreement between all parties should be made that safety, above all else, is the number one priority.
The last line of defence
Despite the efforts of all parties involved, wire strikes can still occur, with devastating consequences. The use of a wire strike protection system is a way to protect a pilot during low-level flying operations, as a last line of defence.
The systems are mechanical blade devices that fit to a helicopter’s body and can cut through power cables – under the right circumstances. The system is effective when the protected parts of the helicopter (generally the windscreen, skid legs and lower main rotor mast) strike a wire at an angle of less than 90 degrees and at a speed of more than 30 knots. But wire strike protection systems are ineffective if the helicopter strikes the wire outside of the parameters described above. Wire strike protection systems are available for most turbine helicopters including the Robinson R66. Despite external similarities, wire strike protection is not offered on the Robinson R44 or the smaller R22.
The human element: focus and refocus
The unfortunate truth is that despite the best efforts of pilots, operators and landholders in preparing for low-level flying, human factors elements will occasionally lead to crashes.
A study undertaken by the US Federal Aviation Administration in June 2023 asserts that pilots can succumb to cognitive risk factors that can affect their performance when conducting low-level operations; the factors include the loss of situational awareness, impaired decision-making and pressure to complete the job within a certain time, whether that be pressure from the client or the operator.
Weather conditions and the time of day were also major factors that contribute to the distraction of pilots and can skew their visual perception of where wires are located.
The study suggests more reconnaissance passes would enable pilots to better recall where wires are, or even discover the location of previously unmapped wires, and that additional preparation would instil greater confidence in pilots, thus minimising potential for distraction.
Nat Nagy reiterates the importance of human factors. ‘Even if you’ve planned thoroughly, you can still become distracted,’ he says.
‘We talk about sterile cockpits all the time, but in the case of avoiding wire strikes, it is absolutely essential that pilots remove as many distractions as possible in the cockpit.
‘Distraction, though, when you’re thinking about 100 other things, is sometimes unavoidable. The important part is that you should have a refocus plan.
‘Recognise you’re distracted, get above the wire environment – 500 feet AGL – then refocus. In other words, get height and get out of there!’
Over recent years, the Aerial Application Association of Australia has been working to educate pilots and landowners about the human factors elements of flying near powerlines. An app has been developed, Look up and Live, to help pilots check the location of wires (in Queensland only) and plan where it is safe for work to be undertaken. The app aims to raise awareness of the hazards and risks associated with low-level flying, to reduce the risk of injury and death.
The association encourages all pilots conducting rural aerial operations to download and use it as part of their pre-flight planning. They also strongly recommend all pilots engage in regular refresher training on human factors and crew resource management (CRM) in the low-level hazard environment. Pilots need to make the commitment to keep on learning and reminding themselves how to avoid wire strike accidents.
The tragic accidents of the Cessna and the Robinson serve as a good reminder to pilots conducting low-level flying that preparation is key.
Further reading
- Wire, the invisible enemy (on the Pilot safety hub at casa.gov.au/pilots, refers to a 2017 article)
- Crash comic in this edition, ‘Strange vibrations’, is about a wire strike
- US Federal Aviation Administration report: Wire-Strikes in Agricultural Operations: A Focus Group Study
- Find these A3 posters below at shop.casa.gov.au ‘Do you have an operational reason to fly low?’
