Esther was unimpressed:

http://www.flickr.com/photos/edyson/2713460125/

That thing is pretty huge. It's not much smaller than a Schweizer 300, which is a substantially more capable aircraft.

So a ducted fan helicopter is now a "jetpack"? Okay...

I dunno....the video on the times site was kind of underwhelming. 2 guys running alongside with their hands out? Why not a tethered flight...get a little more elevation. Also, the martinair site is down now. If it can really do what they say, they will sale like hotcakes. 8,000 ft. ceiling and 30 minute flight time? sign me up!!

so, three guys strap a lawnmower on someone, pick him up and then carry him around?

As a pilot, my first thought when seeing this was that there will be a low altitude in the flight envelope (probably between ten and several hundred feet) where loss of the single engine will result in an uncontrolled descent that the parachute will not be able to slow in time. Takeoff will probably be "Go for altitude and hope for the best".

Although this is a great step forward and will hopefully spark development of the concept, one could hope for backup power of some sort. I'd also like to see what the high speed flight stability is, since it's nearly all thrust without significant lifting surfaces.

a turbo-fanned Solo Trek, though, is that tail a duct?

Myth Busted?

@#2 : The thing is WAAAAAY smaller than a Schweizer 300, for one, it doesn't have a ma-hoosive tail.

@#3 : It's called a jetpack and therefore has jets, it's not a ducted fan helo.

I had a really odd dream in which my father gave me, as a present, a really crappy jetpack he bought from QVC. It ran on a propane bottle. I used it to fly from upstate NY to Long Island and ended up getting my feet wet in Sheepshead Bay before giving up and taking a bus.

It's not WAAAAY smaller unless it would fit inside one, which it does not. Yes, a helicopter has a 25-foot boom, but this thing is the size of a Yugo. I'd say you would need a similarly large space to land or alight either craft.

And you don't need a goofy outfit to fly a helicopter.

It weighs 250 pounds, it should qualify as an ultralight, meaning you could fly it without a pilots license. Or crazy insane aircraft insurance that would come with vectored thrust private aircraft.

It develops 600 pounds of thrust. And has thirty minutes of flight time. Not too shabby.

I'll let the first few hundred be a test pilot for me before I see if I can find a place that rents one.

Balistic parachute are good to pretty low altitudes on ultralights. fifty feet? hundred feet? I forget.

I know the "jet pack" idea is cool, but 250 pounds isn't light enough to walk around with. I wonder if they could mount a seat on the front, put some skids on it to absorb a crash landing, and still keep it under the ultralight limit.

"a gasoline-powered piston engine runs the large rotors"

It's a ducted fan spun by piston engine, not a "jet", not a "turbine" even.

Still, I've hovered helicopters with trees all around me, and this thing could land in a lot smaller space than a chopper.

thirty minute flight time is probably limited by ultralight legal limits. If you could get it listed as an experimental aircraft, put a bigger tank on it, put on that seat and skids I mentioned, and get a vectored thrust rating on your license, hm, nice.

Qualifies as a 'jetpack' for sufficiently broad definitions of the word 'jetpack'.

Wait a minute. Why is the "pilot" all decked out in flight gear and the two guys standing right next to him are wearing picnic clothes?

And why can't the "pilot" pilot the thing without assistance?

If I were to pay $100K for something like this I would want to be able to operate it without two guys standing right next to me.

"My shoes are on fire! I just set my shoes on fire!" - Henchman 24 in Venture Bros.

@16: Read the friendly article. They're working up to solo, higher-altitude flights. They want to walk before they can run—which is a completely sensible testing procedure when you're talking about something that requires power to keep it in the air, else it will drop like a stone.

Did anyone else notice how the tree branches were sucked in? Get too close to one flock of birds and game over (for both you and the birds).

Huntsu@16, apparently, it's still in the "prototype" stage.

but at least it's "working prototype", not vaporware.

http://cosmiclog.msnbc.msn.com/archive/2008/07/29/1230228.aspx

#8:

Just because MythBusters couldn't get something like this to work doesn't mean it's not possible. They're impressive fabricators, but they're not gods. Hell, they frequently miss obvious things.

Anyway, if I recall, the "myth" they busted was that you could do this using a particular set of plans bought off the internet. They never claimed that something similar couldn't work given an appropriate power->weight ratio, and tighter tolerances between the fan and duct.

its fans, its big, its bulky.

I want a REAL Jetpack, like I was promised in the 60s when I was a kid.

http://www.jetpackinternational.com/

it should be small, it should be quick, it should make me feel like James Freakin Bond

http://www.transchool.eustis.army.mil/Museum/Jetbelt.htm

http://www.rocketman.org/index-4.html
http://www.rocketman.org/video/Rose_Parade.wmv

A V4, 200hp, engine drives it. Takuan's link @21 shows that there's a lot of stuff built into the frame directly behind the pilot, possibly the engine itself. Keeps the center of gravity low. That video also shows untethered, but still low (6 foot altitude) flying. It looks "relatively" stable, which is to say, his hovering is about on par with what you would expect from a helicopter or other vtol aircraft that only weighs 250 pounds.

Big big helos benefit from the extra weight giving them more stability.

The article says they're specifically shooting for ultralight status, which makes sense from a legal standpoint. and also explains some otherwise odd engineering decisions.

IVAN256: I was snarking at Mythbusters inability to make it work, co-opting their own verbiage and stating that they had in-effect created a myth that you can't make these things work.

I didn't think I was being that complex.

@23: The problem is that you can't make something as small as you describe stay in the air for very long. They just don't have enough fuel.

In order to have enough fuel to stay in the air for longer, you have to go with a bigger gizmo. There's no way around that until we have nuclear reactors small enough to strap on our backs…

"a Wisconsin air show"

This ain't just any air show, it's the Experimental Aircraft Association Fly -In with all sorts of things that fly (and some that shouldn't -but do!). It's the largest experimental air show around and truly a spectacle. Spaceship One was there a few years ago -and left to go straight to the Smithsonian. There's almost always a B17 and many Mustangs and other vintage aircraft. The airshow is a few hours of amazing aerial weirdness. I won't spoil the fun but the finale may literally burn your eyebrows off.

The fun is in the new experimental aircraft. It's the first place I saw an ultralight back in the late 70s or early 80's. You used to not be able to get in unless you flew in -or were a Boy Scout (no lie) but it eventually dawned on them they'd make pretty close to 14 bazillion bucks so they opened it up to everyone.

The Museum is extremely cool and the week long event is well worth a trip to Wisconsin -land of large fiberglass animals, Taliesin and DR. Evermore's Art park. And really crappy beer.

You know, if they have to make it that big, then they should just go ahead and make it a Jet-Cycle or a Motoroid. Then I can go hunt me some Boomers.

Haha! Ducted fans, I totally called it.

What about this thing:

http://www.liveleak.com/view?i=d75_1186237060

That looked fun,and it was decades ago...they have on in a museum somewhere in the USA i think.

warning:crappy sound and picture quality in the link.

Surely we could make something pretty compact these days what with nanotech/quantum entanglement and micro nuke power don't ya think?

Gee, too many cynical pragmatists here to day. It's not the Rocket King, but I think it's awfully neat.

Trent, I'd like to see a seat, but I'm thinking one of the issues they're avoiding is center of gravity. THe thing only weighs 250 pounds. Take a 200 pound pilot, and put him at the same height as the fans at the top, then you've got a naturally unstable machine. Lean forward, and the machine wants to do a forward flip and you're dead.

By having the fans up high, and a lot of the weight hanging down below, they might make it more stable, like a pendulum naturally finds center, instead of like trying to balance a three foot long stick on your hand with a ten pound weight on the end.

Cause if that thing flips, you're dead. And if it's really unstable, it'll tend to want to flip.

This stability problem is probably what's been keeping the Moller Machine as vaporware for ... thirty? years. The center of gravity is at the same height as the fans.

"Before long he had venture capital financing and a PowerPoint presentation."

LOL don't they all.

Don't fall through your own downwash.
Don't fly upside down.

Contemplate this. Extrapolate.

Okay so it's not a real jet pack but it still beats the heck out of every other kind of personal powered aircraft I could land on my roof.

Contemplate this. Extrapolate.

Well yeah, but flight and piston engines have already had over a century of intensive development. I doubt the 10 year learning curve for a new piston powered flight machine could be as steep as the first 10 years of cell phone technology.

make this cheap and go the other way
http://www.sub-find.com/newt_suit.htm

...Isn't this just a ducted fan version of that twin prop "decapitator" job of which the prototype was auctioned on eBay last year? ISRT "Mythbusters" may have done a piece on that one as well.

C'mon, Ross. You're an AmeriCAN, not an AmeriCAN'T.

LOL @ all the people pretending they didn't wish they were flying it. God people can be petty.

me want... lots... now...

mind you, I can just see the knee-jerk legislation put in place to prevent Joe Public from using one for the commute... just like they very quickly legislated Segways out of the picture for urban use...

@34 Antinous: Cell phones are a technology limited by component's size. Vtol ducted rotor belts are a technology limited by thrust/stability requirements needed to balance a 6', 200 lbs. human.

I doubt tiny fans could generate enough lift.

Always with the impossibilities. Fortunately, inventors are crazy enough to try to break the laws of the known.

nanomaterials? gossamer steel? Same old engine tech but everything weighs 5 kilos?

"know the "jet pack" idea is cool, but 250 pounds isn't light enough to walk around with. I wonder if they could mount a seat on the front, put some skids on it to absorb a crash landing, and still keep it under the ultralight limit."

How about they strap the thing to an exoskeleton and just call it an exo-suit already. That way I don't need to feel concerned it is going to tip forward and crush me or break my neck.

With wings or rotors, if the power goes out you still have lift, trading altitude for airspeed.

With this setup, when the power goes out, so does your lift. In the words of Graham Chapman:

"Notice they do not so much fly as plummet."

#41: Knee-jerk my ass!

If people commuted with these the noise pollution would be awful, and backyards and parking lots across the nation would be littered with the bodies of people who were trying to fly and make cell phone calls at the same time.

If these things go legal I'll buy a cherry picker and make a mint plucking the victims out of trees and peeling them off billboards.

there is no reason to mount it on your back other then the "wow" factor. hell, vespas are smaller and lighter, but we don't mount them on our backs. this thing should have a cockpit.

OK, right through my teenage years I dreamed of jetpacks, of an eccentric inventor who would enable me to fly, if not to the moon, then at least into the next suburb or onto the roof of whatever girl I was in love with that week.

And now it turns out this man lived just down the road from me the whole time.

Glenn and Vanessa used to come into a video shop I worked in all the time. Hell, I probably rented him The Rocketeer for all I know.

To those blathering on about whether it's a jetpack or a 'jetpack', whether Mythbusters busted it or not, whether it's size will stop you from moving properly - read the article, in particular the Franklin quote.

He made it in his garage. Over years and years and freaking years. According to local media he used to put 20 bucks a week into developing it. I can tell you for certain - this isn't some rich guy. This a dude in crappy sneakers who drives a falling apart car and has a gaggle of kids hounding him over whether they're allowed Spy Kids or Monsters Inc.

Undeniably awesome indeed.

does it stabilize by pilot correction or fly-by-wire?

Give it 10 or 20 years and we'll see something like this fold down into a briefcase... (We really need an anti-grav metal so it's smaller, weightless, and and not a deathtrap if the engine fails.)

#48:
"there is no reason to mount it on your back other then the "wow" factor. hell, vespas are smaller and lighter, but we don't mount them on our backs. this thing should have a cockpit."

Cockpits have to be made of something. That something has mass, and therefore weight. This, in turn, requires more thrust to lift, which requires more engine or more fuel, both of which, in turn, also add more weight. Every gram of mass you can shed from the design will make it easier to make the machine work, and make it work better.

Also, this -is- a bloody "jet pack", and to date the only real commercial success of such machines that I know of has absolutely revolved around that "wow" factor anyhow.

Son, we life in a world that has things. And these things have to be made out of stuff, stuff that has mass. Whose going to eliminate that mass? You?

You weep for jet propulsion and curse ducted fans; You have that luxury. You have the luxury of not knowing what I know: that mass, while tragic, probably saves lives and that gravity and inertia's existence, while grotesque and incomprehensible to you forces the ratio of power to weight upward in order to save lives.

You want things to be made of stuff, because deep down in places you don't talk about at parties you want things to have mass, you need things to have mass. We use words like "thrust", "vector" and "lift". We use them as the backbone of a life trying to get rich nerds airborne, you use them as a punchline.

I have neither the time nor the inclination to explain myself to a man who rises and sleeps under the blanket of the very physics nature provides and then questions the manner in which nature provides it. I would rather you just said "thank you," and went on your way. Otherwise, I suggest that you pick up a slide-rule and pick a drafting table. Either way, I don't give a damn what you think you are entitled to.

how much of it is carbon fibre right now?

Did you order the ducted fan?!? I think I deserve an answer. Did you?

GREGLONDON:

:)

Sethum: Vtol ducted rotor belts are a technology limited by thrust/stability requirements

belts?

There's a chart somewhere in aeordynamics 101 that shows the overall efficiency of an engine versus the speed at which the engine is flying. Props are the most efficient thing for the hundred mile an hour deal. Get a couple hundred, and you start looking at turbofans. Faster yet, and it's turbojets. Above that, it was ... something. And above that it was crazy tech like ramjets and similar oddities.

This was just the basic aerodynamic efficiency of producing thrust. So, if you want to move slowly, like hover, you're best off with something like a big honking rotor. These guys must have figured out a way to get a light enough piston engine with enough power to spin a ducted fan fast enough to overcome the fact that it won't be as efficient as a big rotor. A turbojet will be even harder. The smaller you get, the less efficient it is, so I think the only way to generate enough lift for hover is to generate even more so that you overcome the inefficiencies inherent in the system.

So, no, they probably won't make ducted fans smaller. If anything, they'll figure out a way to make turbojets more powerful so they can generate enough power that even with all the inefficiencies, there is still enough power to hover.

ackpht: when the power goes out, so does your lift.

Yeah, that has me worried just a bit. Balistic chutes work at pretty low altitudes, but still. The moller design (paper design as far as I know) had something like 8 engines and 8 fans, or something. Lots of redundancy, with the idea that you could lose any one engine/fan whatever, and still have enough for a controlled landing. The moller beast isn't available yet, though, and I don't think it's flying either. Haven't followed it for a while. Gave up on it long ago.

Sorry, but IMO, any comment that begins with "Son, ...", seems extremely condescending. Its difficult to take the rest seriously. Especially when the next line says "we life in a world..."

LogrusZed, I haven't seen anyone here say that they feel entitled to jets, turbines, non-Newtonian physics or anti-gravity. People are just speculating and discussing the relative merits of the device mentioned in this article. I am asking you to make your tone less insulting.

Tak, what the hell is carbon fibre? Is it anything like the carbon-fiber breakfast cereal I ate this morning?

http://blog.wired.com/gadgets/2008/07/100k-jetpack.html

only the Korean ones. I'm very curious as to how the weight is distributed by materials choice in this toy. That would be the first place to proceed from.

For God's sake, just don't sleep in a room with a jetpack running.

time warp again

now you're supposed to say; I knew you'd say that

JAKE0748: hehe, I can't tell if you're kidding or you really have never seen "A Few Good Men".

And a few people have lamented this being ducted fans rather than a traditional "jet" system, while others have talked about doing things which would add even more weight/mass to it.

Please enlighten me. What is this time warp of which you speak?

@#30
http://video.aol.com/video-detail/the-wasp-williams-aerial-systems-platform/51818459

Jake
http://en.wikipedia.org/wiki/Carbon_fiber

RE: Mythbusters:

They screw a lot of things up. I think the last episode I watched was the one about yawning being contagious. It was the crappiest excuse for a scientific study I've ever seen, and then they did just a side-by side comparison of mean times before yawning. It was preposterous.

I know it's a show for fun, but the fun is of applying the scientific method to really silly things. Just doing silly things is... just silly.

Jake0748: Oh, and "fibre" is "fiber" spelled in the traditional English manner.

some other words you may come across are "Colour" which means "color", "Blonde" which means "blond", "cheque" which means "check", and "twat" which is often used to refer to people who accuse people of poor spelling for using English properly.

But I did put the word "life" when I meant to type "live" so you got me there.

it seems Antinous and I are entangled in a chrono-synclastic infundibulum. My posts appear before his that they are prompted by. I blame Satan.

Alternatively, you can blame quantum. For anything.

Oh, thanks so much for enlightening me. I had never heard of carbon fiber, or fibre. I guess I must be blonde. I will immediately send you a cheque for being such a twat.

So, do you feel like working on that condescending thing?

Takuan, sounds like a Scottish cocktail party.

it could be a walrus

the walrus was Paul.

it was the will of jebus!

Still waiting for my Hiller platform. Sigh.

did you have a good look at the Williams WASP? Maybe the pattern can be re-engineered with new materials.

Wouldn't it actually be more practical to learn lucid dreaming and enjoy not only flying (wherever and however you want), but also a practically infinite amount of other activities including sex and what else have you? It might only be a dream, but that doesn't make it any less real... plus it's free for everyone

Awesome? I see three big guys holding up one little guy who's wearing a strap-on double-barreled fan. I predict that this will be about as important as the Moller "flying car."

bshock, the guy they're holding is a reporter, not an employee of the company that built the thing. If you want to see some untethered flying, look here

http://cosmiclog.msnbc.msn.com/archive/2008/07/29/1230228.aspx

And it's an ultralight, which means it's about as important as ultralights are. Even if some guy develops a rocket belt that only weighs 20 pounds and has five hours of flight time, it'll still be an ultralight, and have a bagillion restrictions that come with ultralights.

"They never claimed that something similar couldn't work given an appropriate power->weight ratio, and tighter tolerances between the fan and duct."

...Or, in other words, use a higher quality of duct tape to hold things together. :-P

I really want to hear the news that the guy was successful in taking this thing up to 500 feet. It's like skydiving in reverse.

Take it easy on the mythbusters, folks. They are just entertainers and they do make an effort to be candid about that.

They openly admit they don't have scientific backgrounds and may not be capable of reliable, empirical observation in every instance. They even do some of what they do just for fun... which makes sense, because they're hosting a TV show.

If they were making claims that they're proper scientists and that everything they do is a respectable experiment then I'd give them flak too, but they don't try to make that claim so I think it's a little unfair to hold them to it.

They also welcome viewer feedback, so heck, instead of critiquing them elsewhere for their shortcomings, head over to their forum and lend them a hand in doing a better job with constructive criticism :)

One of the big issues everyone is missing: This can't be an ultralight. To qualify as an ultralight, not only do you have to weigh under 254 pounds, you also have to have a stall speed under 20-some knots. The FAA specifically disqualifies all hovering aircraft as ultralights by using this requirement. No matter how light it is, you still need a pilot's license and a airworthiness certificate. Try finding an FAA bureaucrat willing to risk his career licensing the first one of these!

As for the Myth Buster's machine, I consulted with them on that episode. They knew going in that it wouldn't work. The plans they used were a rip off of Trek Aerospace's work. Unfortunately, the guy who made the plans had no concept of lift or stability. They proved what they set out to prove.

Martin's Jetpack is a testament to what a tinkerer in a garage with perseverance can do. He has achieved what Trek did 6 years ago. Unfortunately, he's now taking money for it, much like Moller.