Kiwi jetpack man flying high

File photo / APN

To infinity and beyond ... Kiwi ingenuity is alive and well and flying a jetpack 5000 feet above sea level.

No longer the stuff of comic stories and science fiction, the Martin Jetpack is soaring to incredible heights, and could go even higher, according to its inventor Glenn Martin.

The jetpack, which relies on two powerful "superfans" to get airborne, is attracting international interest, including from the US military, but its potential uses are wider.

Japanese authorities dealing with the earthquake-damaged Fukushima nuclear power station had even looked into using it to take test samples above the plant, a task for which Martin said it would be ideal.

The inventor's sky-high achievement features on TV One's Sunday tonight, with the jetpack in action above the Canterbury Plains.

It's a big jump from earlier footage of the invention tentatively hovering just a few feet off the ground, which caused US media to joke about whether that constituted flying at all.

That mocking hurt Martin, for whom safety has been paramount.

"You know, it's a personal thing," he said. "It's a moral thing, and you know I can't put something out unless we've all done our best to make sure it's as safe as it possibly can be."

For that reason, the flight near Ashburton was piloted by remote control, with a crash-test dummy in the pilot's position. The machine flew to 5000 feet, then down to about 2000 feet before firing a rocket-propelled parachute. From there it sailed safely to the ground without damage.

"We have to do the dummy first and then we'll do the person second," Martin said.

"It's still a lot of fun but what we're discovering now is it's got a serious use as well. You can get into places you can't go. You can use it for search and rescue operations that you couldn't do in a helicopter."

The jetpack could go places where helicopters couldn't, such as the sides of cliffs and between trees and buildings.

The next step would be to develop a parachute similar to those used on jet pilot ejector seats which opened faster than the rocket-propelled type.

"Nobody has fired a parachute from a jetpack before," he said.

Sunday correspondent Ian Sinclair described watching the jetpack soar to 5000 feet as "astonishing".

"The sceptics hurt him but he knew what it could do," said Sinclair, adding that Martin's was the most incredible story he'd covered in 35 years.

To develop the jetpack to this point had cost $12 million in savings and venture capital and 30 years of Martin's life. And the intention was to float the company on the sharemarket, to raise capital to get the jet pack into mass production. Early estimates were that one might retail for about $60,000.

* Story on TV One's Sunday, tonight.