The helisaw in operation alongside The Lines Company’s live 33kV Kuratau power line in Rotoaira Forest, where vegetation was cleared without turning power off. Photo: Supplied
A Taupō company has used a helicopter to trim trees near live high-voltage powerlines in what it says is a first for New Zealand and milestone for lines companies.
Aerial Arborists Limited uses a specially designed ‘helisaw’, suspended from a helicopter to clear branches away from powerlines.
The milestone was achieved on The Lines Company’s 33kV Kuratau power line through Rotoaira Forest, where vegetation was cleared alongside a high-voltage line without turning power off to customers.
Andrew Peckham, Aerial Arborists director and co-owner says it shows helisaw operations can be safely used for live-line vegetation management, under suitable conditions.
He says the operation was supported by robust planning, specialist aviation capability, suitable forestry growth and careful outage mitigation.
By maintaining safe clearances between trees and conductors, lines companies and forestry companies can reduce the likelihood of faults, unplanned outages and fire risk, while improving long-term supply resilience.
“Completing this work safely beside a live 33kV line is a landmark achievement for Aerial Arborists, TLC and the wider New Zealand electricity and forestry sectors,” Andrew says.
He says the helisaw technology will enable vegetation to be managed at scale in areas where conventional ground-based arborist operations are slow, expensive and dangerous.
The purpose-designed saw blades trim trees along power line corridors and are particularly effective in remote, steep or densely forested areas where ground access is difficult.
The helisaw technology won the Innovation in Energy Award at the 2025 New Zealand Energy Excellence Awards.
Judges recognised its contribution to arborist safety, lower costs, particularly in remote areas, and more proactive vegetation management.
TLC first trialled helisaw operations in April 2024, clearing 950 metres of radiata pine along a 33kV corridor in just over an hour.
Since then, it has become an increasingly important part of TLC’s vegetation management approach.
TLC general manager Network Gerhard Buitendach says vegetation is one of the most persistent risks to electricity network reliability, particularly in rural and forestry environment.