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."

No parachute

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.

Re:No parachute

Note that he did, however, wear a helmet, which I'm sure would've totally saved him from the 1000ft fall.

Re:No parachute

hahahah

No, but it would save him from head trauma in the event of a failure during take-off or landing, which is probably the reason behind it.

Re:No parachute

The helmet is probably mainly for insurance purposes.

I'd imagine it's already pretty difficult getting insurance to fly over a gorge with a rocketpack.

Re:No parachute

He would need to get close to the ground to land. Doesn't take a high drop to crack the skull.

So presumably that's where the helmet might come in handy.

Maybe he's confident of not making a big mistake, but not so confident he won't make a small slip up on landing.

Re:No parachute

Take-off and landing ARE afterall the dangerous parts of every flight. Once you're up there, if nothing else, you at least have time to react when something goes wrong. When landing or taking-off that ground thing that can hurt you is less than a second away.

Re:

Either that or he is full of hot air.

iwantoneforchristmas

Goes without saying really, but iwantoneforchristmas.

Safe? Not without a parachute!!!

Can't a parachute be strapped on the front or something? This guy made it across without being harmed, but I would hardly refer to such an activity as safe. No redundancy = not safe.

Re:

There is a certain minimal altitude below which the parachute is quite useless. Under controlled conditions, you can jump even from comparatively low towers, but this jetpack most likely is not designed to climb into that altitude. Perhaps flying horizontally over a canyon as in this case *could* make this difference, but if this device fails when you are 200 feet above the ground, you are screwed.

Re:Safe? Not without a parachute!!!

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.

Re:

As a hang glider pilot, below a few hundred feet your reserve is worse than useless. The canopy just doesn't inflate fast enough to make any difference.

This guy was over a 1000 foot canyon, so if he threw a parachute in the middle it might help, but the things don't really steer so he'd probably just end up hitting the wall and falling anyway.

Re:

BASE jumping is a special case where your parachute deployment is very carefully orchestrated and your parachute is also carefully designed to be steered. Plus you're not carrying a heavy, malfunctioning jetpack on your back. Even then, BASE jumpers frequently crash into things.

A BASE jumper deploying his chute from a stationary position on the edge of the gorge is a bit different from this guy, ten senconds into his flight (and ten seconds from landing) realizing he's got a problem and deploying a chute

Re:

TFA says he flew over a deep deep gorge. Why did you go to all the trouble of finding that in wikipedia when you could have RTFA much more quickly?

Most of the flights he makes are not over deep gorges. So clearly this is not part of his normal equipment. Since every other flight he makes would kill him if the equipment fails, and he makes far more flights not over gorges than over gorges, what is the sense for him to add a parachute for only this one fight.

Movie?

Anyone got a movie of this stunt? Sounds really cool, would be even cooler to actually see him doing it.

Re:

It seems to be in various places over the interwebs [guardian.co.uk]

Eric Scott != Rocketman

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 [the-rocketman.com] remains THE Rocketman.

Re:hydrogen peroxide?

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.

Re:

I wouldn't be surprised to read that the jetpack he is using is based strongly on the engine that powered the ME-163. The 'fuel tank' consisted of two bladders - one full of concentrated hydrogen peroxide and the other full of high grade methanol.

Actually wikipedia says that the first component wasn't H202 but N2H4 - but I'm skeptical. I've always heard it was concentrated peroxide, and lab experiments I've seen support that theory.

Regardless - back in WWII the biggest threat to the ME163 pilots wasn't ge

Re:

"hydrogen peroxide, huh? Does that react with something or what?"

Catalytic decomposition, I would guess. Simple and reliable, like the hydrazine RCS thrusters on spacecrafts.

Re:

"hydrogen peroxide, huh? Does that react with something or what?"

Catalytic decomposition, I would guess. Simple and reliable, like the hydrazine RCS thrusters on spacecrafts.

RCS exhaust is lethal to unprotected humans. At normal shuttle landing sites huge fans are used to blow gas away from the orbiter before any seals are cracked. At emergency landing sites ground crews are briefed to keep clear of the spacecraft.

Eric Scott is still alive so this is not like the RCS system on a spacecraft.

Re:hydrogen peroxide?

...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?

Re:hydrogen peroxide?

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.

Re:

hydrogen peroxide, huh? Does that react with something or what?

Good old catalytic decomposition, I would guess. Simple and reliable, like the hydrazine RCS thrusters on spacecrafts.

Re:average speed of 180mph!!

Google says [google.com] you got it wrong too.

Silly Americans, switch to metric already :D