Pictured: The £50,000 jet pack that lets you become a real-life James Bond

But – outside of the world of comic books – the jet pack has never really got off the ground.

Until now. For a designer called Glenn Martin believes he has come up with a one-man flying machine that actually works.

Glenn Martin shows off his jetpack

The Martin Jet Pack has made its public debut at AirVenture, the world’s biggest air show.

It didn’t travel very far (50ft), very high (6ft), or for very long (45 seconds) but that wasn’t the object of the exercise, according to its creator.

‘I wanted to prove that the technology works,’ said Mr Martin. ‘Six feet or 600ft, it makes no difference once you get airborne.’

The huge crowd of aviation enthusiasts at Oshkosh, near Milwaukee, Wisconsin, seemed to agree as the flight was celebrated with wild whoops and cheers.

Mr Martin, a 48-year-old father of two from Christchurch, New Zealand, was five when he first dreamed of having a magic flying belt.

He has spent years perfecting his jet pack, which he hopes to start selling for £50,000 each next year.

After years of building prototypes since his university days, he said he achieved his breakthrough 11 years ago in his garage workshop.

His wife Vanessa was recruited as a test pilot for what would become the Martin Jet Pack. ‘I took some precautions,’ he said. ‘I tied the thing to a pole in the garage so Vanessa wouldn’t go flying through the roof.’

Mrs Martin said: ‘Everything went well, and I was hooked immediately.’ Later Mr Martin also enlisted his son, Harrison, then 15, as another test pilot as he perfected his jet pack, which owes more to the hovercraft than the jet.

A motorbike engine running on petrol uses car fan-belts to drive two fan propellers that spin horizontally inside what looks like two oversized soup cans.

This ‘ducted fan’ design is more efficient than the unshielded rotor of a helicopter.

The engine, fuel tank and pilot are positioned between and below the lift-fans to lower the centre of gravity and prevent the machine turning upside down in flight and diving into the ground.

Two control levers protrude forwards beneath the pilot’s arms. The left one is a joystick controlling forward and backward movement and sideways tilt of the propellers, for left and right turns.

The right lever is the accelerator, the engine start-and-stop switch, and a button for the emergency parachute, located behind the pilot’s head.

Mr Martin recently gained backing from a group of venture capitalists and quit his regular job as a biochemist to develop his machine.

He said: ‘Within six months I’ll take it to 500ft, then the sky’s the limit.’ He believes its ideal flying height will be between 500ft and 1,000ft although it could go up to 6,000ft. He said his machine can stay up for 30 minutes, a flying time he believes will make it a best-seller.

He and his backers believe it will be ideal for commuters, ranchers, the miltary and fire crews tackling forest blazes.

And, of course, it also has appeal as the ultimate boy’s toy.