Any aircraft flying at low levels is at risk of a wire strike. Agricultural aircraft, whether fixed wing or helicopter, are especially susceptible due to the nature of the work they do.
Wire strikes are preventable, but only with a well-planned safety programme to identify hazards and put mitigations in place. With ACC, WorkSafe, and Federated Farmers we've developed an information sheet [PDF 170 KB] providing basic guidance on how to manage wire hazards.
Wire strikes often occur in fine weather when there’s good visibility. In many cases the pilots knew the wires were there.
Important things to think about include:
The farmer must provide a detailed hazard map showing wires, high fences, and other hazards.
Hazards in the surrounding areas, especially turnaround areas, must also be identified. In an emergency, you may need to fly outside the intended operating area. You should also talk to neighbouring landowners or other operators who have experience working in the area.
In addition to the hazard map, you should do a full reconnaissance of the area you are about to operate in, from both the air and the ground. Take note of any structures using power and watch for any poles as they may have wires connected that you can't see.
Also watch for single wires strung between farm buildings. They’re particularly hard to see, and can also be attached to hidden structures. Streams, gullies, and rivers all potentially have wires strung across them.
Transpower provides information about electricity transmission lines(external link) on its website.
Also, the Electricity Networks Association website(external link) shows the controlling network company of each area. You can use this to contact the network company to get information on electricity lines in that area.
Wherever possible, you must reduce risks to ensure the farm is safe for aerial operations. This could mean the farmer will be required to remove, or lower, all aerial wires before operations start.
Where that can’t be done, the risk must be mitigated: marking the wires, for instance, and putting them on a hazard map you can give your pilot.
On the day of your safety briefing, you should discuss any wires or other hazards with your contractors. You should have written documentation detailing the information about any wire hazards in a contract.
A healthy and safe workplace starts with identifying and understanding what your work-related health and safety risks are, particularly those with the potential to cause people serious injury or illness.
Make sure everyone involved in an operation, such as the farmer and ground crew, are fully aware of potential risks and what to do in an emergency.
As well as identifying and managing hazards, you, the farmer, and the ground crew need to know what to do – and who is responsible for what – in an emergency. Some questions to think about are:
Operators with aircraft working routinely in the wire environment should consider installing a wire cutting system on their aircraft to help manage risks.
A wire cutting system is designed to channel a wire or cable into the cutter to score it as it travels into the cutter assembly, to ‘cut’ the wire before aircraft contact. The system is generally fitted to undercarriage legs and to the middle of the windscreen.
We recommend all pilots be trained in wire strike avoidance. Wire environment courses are regularly run in New Zealand.
You should report all aviation accidents and incidents to us. We need to know the cause of an occurrence to help industry understand how to prevent it from happening again. Our investigators will work with you to find out what happened and why.
For more advice about wire safety, talk to your industry body.