Hire wire team flies into check transmission lines

Justin Brewer and Donald Leask move a corrosion detection robot on a live transmission line near Halfway Bush in Dunedin yesterday. Photo by Stephen Jaquiery.

He survived the experience.

"It was just a bit of tingle when you bond on and bond off. You don't feel anything while you are holding it," he said.

It takes four years to train as a high voltage live liner - affectionately known as "dopes on ropes" - and yesterday was Mr Brewer's first time "bonding", which he did suspended from a helicopter high over South Dunedin under the eye of colleague and senior live liner Donald Leask.

The men work for line maintenance company United Group and each year, they, together with data man Des Hurrell, Dave Padfield from an Australian testing and research company, and project manager Mike Taylor, from Linetech Consulting, come together to carry out six weeks' corrosion detection work on Transpower's high voltage transmission lines.

Gathering data on overhead power lines around Dunedin at the moment are (from left) Des Hurrell, Donald Leask, Justin Brewer, Dave Padfield, Adam Joseph, Pat Ashby and Mike Taylor. Messrs Leask, Brewer, Joseph and Ashby are wearing the Faraday suits which allow them to work on live, high voltage power lines without risk of electrocution. Photo by Gerard O'Brien.

From the helicopter, Mr Padfield remotely controls the robot, moving it along, collecting data on the line's condition, before the live liners detach it and the operation moves on to another line.

Mr Taylor said the team, mostly from the Wellington region, had done the testing for the past five years. This was its first time in the South Island.

They spent the day working on the Halfway Bush-South Dunedin lines yesterday and will spend the next few days working on the Roxburgh-Three Mile Hill lines, before heading south to check lines around Invercargill and Bluff.

Mr Leask said live lining, especially from helicopters, was high-risk work. Safety was paramount because there were "no second chances" with 220,000 volts of electricity.

The rope suspending live liners from a helicopter was specially made, as were the $5000 Faraday suits each wore. The suits were threaded with stainless steel so they had the same potential to carry electricity as the line, meaning any electricity flowed around the person instead of through them. Underneath the suit the men wore fire retardant overalls and merino clothing.

Mr Leask said there was so much energy going through the line that when you reached your hand out towards it, it could, attracted by the suits, arch up to 30cm to leap into your hand.

Choosing a good helicopter pilot was also important, and the crew preferred to go with HeliPro pilot Mike "Yoda" Reid, who flew them around Dunedin yesterday.

"He's a Jedi knight. I tell you, there's not many pilots that like to sling humans on a 30m line around transmission lines."

The whole exercise worked because nothing was grounded, but there were always risks, including arcing electricity.