Not quite Rocketeer, but jet pack's a start

OSHKOSH, Wis. — This isn't how a jet pack is supposed to look, is it?

Hollywood has envisioned jet packs as upside-down fire extinguishers strapped to people's backs. But Glenn Martin's invention is more unwieldy: a 250-pound piano-size contraption that people settle into rather than strap on.

As thousands watched Tuesday, the New Zealand inventor's 16-year-old son donned a helmet, fastened himself to a prototype Martin jet pack and revved the engine, which sounded like a motorcycle. Harrison Martin eased about 3 feet off the ground, the engine roaring with a whine so loud that some kids covered their ears.

With two spotters preventing the jet pack from drifting in a mild wind, the pilot hovered for 45 seconds and set the device down as the audience applauded.

The Martin jet pack can — in theory — fly an average-size pilot about 30 miles in 30 minutes on a 5-gallon tank of gas. The apparatus was unveiled Tuesday at EAA AirVenture Oshkosh 2008, the annual aviation convention of the Experimental Aircraft Association in east-central Wisconsin.

"Wow, that went better than expected," Glenn Martin, 48, said afterward. "People will look back on this as a moment in history."

That remains to be seen. Federal regulations limit the use of such devices, and it's unclear whether people will shell out $100,000 for a jet pack whose capabilities have been demonstrated on paper but not in the air.

For Martin, the jet pack is the culmination of a dream that began when he was a 5-year-old in Dunedin, New Zealand. For those who remember childhood dreams of flying and comic-book visions of the 21st century, the jet pack suggests the possible fulfillment of the yearning for those long-promised gifts of technology.

Buck Rogers and James Bond used fictional jet packs, and since the 1960s, several real jet-pack designs have been forged from metal, plastic and propellant.

The Martin jet pack is designed to conform to the Federal Aviation Administration (FAA) definition of an ultralight vehicle, which weighs less than 254 pounds and carries only one passenger. Although the FAA could always change its mind, the ultralight designation means riders won't need a pilot's license.

His white jet pack with black trim stands on a brick-sized base with two legs sprawled behind it. The pilot steps backward into the straps of a shoulder harness, his shoulder blades resting against two wide upward-facing fans that provide the thrust.

There's an emergency parachute that's effective above about 400 feet, and an impact-absorbing undercarriage that can soften a rough landing or a short fall, Martin said. He's refining the safety features for those heights in between.

"If someone says, 'I'm not going to buy a jet pack until it's the size of my high-school backpack and has a turbine engine in it,' that's fine," he said. "But they're not going to be flying a jet pack in their lifetime."

It is also not, to put it bluntly, a jet.

"If you're very pedantic," Martin acknowledged, a gasoline-powered piston engine runs the large rotors. Jet Skis, he pointed out, are not jets, and the atmospheric jet stream is not created by engines. "This thing flies on a jet of air," he said.

Martin, who quit his job as a pharmaceutical-sales rep to launch his jet-pack company, said venture capitalists are backing him, but he didn't give names.

Reaction to the test flight was mixed. Attendees with aviation backgrounds raved, calling it an engineering marvel and saying the 45-second flight was fantastic proof that the idea works. Others who hoped to see the machine go higher and move in different directions seemed disappointed.

Martin began taking orders Tuesday for jet packs to be delivered at next year's AirVenture, though he's keeping his sales expectations in check. After all, other entrepreneurs who chased the idea for about 50 years were unable to get off the ground.