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Rocketman Crosses Colorado Gorge
nandemoari writes "Remember the 1991 film, 'The Rocketeer,' where a young pilot uses a jetpack prototype to become a masked vigilante and win the heart of Jennifer Connelly? That scenario isn't as far-fetched as it once was, given that an American stuntman recently used a jetpack to soar over Colorado's Royal Gorge. The stuntman in question is one Eric Scott, who recently appeared on CBS' Early Show and a variety of local cable channels after making his daring leap. Scott has been testing jetpack devices for 16 years, and was confident that he wouldn't plummet to his untimely death when he straddled the Gorge above the Arkansas River earlier this week. Despite an enormous gulf between the two sides — 1,500 feet across and 1,000 feet down — Scott made the trip safely."
Note that he didn't wear a parachute. He's been doing this for years, apparently without serious mishaps, so I suppose he had reason to be confident.
Hydrogen peroxide naturally decomposes into water and oxygen gas: 2(H2O2) -> 2(H2O) + O2 but it's a very slow reaction. But, throw in a catalyst like silver and it happens in milliseconds. It's a highly exothermic reaction, so at those rates, it actually produces oxygen gas and superheated steam, which is directed through a nozzle. The catalyst isn't used up, so yes you could just refuel and take off again, though the equipment probably needs time to cool down.
Like != identical to.
A hydrogen peroxide jet is a monopropellant thruster: all you need is the H202 and a catalyst, which isn't used up. Hydrazine thrusters come in two forms, monopropellant and bipropellant. The monopropellant type is a lot like an H202 jet, and the exhaust is ammonia, nitrogen and hydrogen.
The bipropellant form mixes hydrazine and N204, which is hypergolic - it ignites itself. The exhaust is nitrogen, carbon dioxide and water. The concern with hydrazine thrusters is leaking, unburned hydrazine, not the reaction products.