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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.
Goes without saying really, but iwantoneforchristmas.
+1 IDisagreeSoHeMustBeATrollOrAnAstroturferOrAShill
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.
There is a certain minimal altitude below which the parachute is quite useless.
Hang glider pilots carry ballistic parachutes which eject themselves from a container and open at the end of a tether. That way you only fall far enough to inflate the canopy. A parachute like that could work from 100 feet or so.
The rocket here seems pretty reliable but I would worry about a control system failure.
http://michaelsmith.id.au
...and that is precisely why they are using hydrogen peroxide instead of hydrazine or one of its derivates, even though hydrazine has a higher energy density and, at the same time, it is less corrosive and can be stored for an extended period of time. But the principle of the thruster is the same - catalytic decomposition of a monopropellant. What exactly does it make it "not like the RCS system on a spacecraft", other than the choice of the monopropellant?
Ezekiel 23:20
Google says you got it wrong too.
Silly Americans, switch to metric already :D
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.
Eric's a fine stunt specialist with a lot of experience and his jetpack work goes way beyond regular stunt work. But there is a stuntman who rightfully earned and uses the name "Rocketman", and it's not Eric Scott. The real Rocketman built many stunt devices, including Evel Knievel's. He also headed the team to build and fly the first amateur rocket to cross the internationally accepted altitude defining "space". Of course he's not going to fault Eric for the press's inevitable use of the name "Rocketman" -- they do it every chance they get. But these other guys get called that and then that name forgotten. But Ky Michaelson http://www.the-rocketman.com/rocketmanhist.html remains THE Rocketman.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B