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Practical Jetpack Available "Soon"
Posted by
kdawson
on Tue Jul 29, 2008 05:41 PM
from the coolest-desire-left-to-mankind dept.
from the coolest-desire-left-to-mankind dept.
Ifandbut was one of several readers to point out the arrival in Oshkosh of the first practical jetpack. It was invented by a New Zealander Glenn Martin, who has been working on the idea for 27 years. He plans to sell the gizmos for somewhere in the neighborhood of $100K. While previous attempts at jetpacks have flown for at most a couple of minutes, Mr. Martin's invention can stay aloft for half an hour. Both "practical" and "jetpack" may need quotation marks, however: The device is huge and it's incredibly noisy. And, "It is also not, to put it bluntly, a jet. 'If you're very pedantic,' Mr. 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. Or, more simply, it flies."
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Huh? (Score:5, Insightful)
Re:Huh? (Score:5, Funny)
Parent
Re:Huh? (Score:5, Interesting)
To be honest, I definitely would be interested in a story titled "Impractical Not-Really-A-Jetpack Maybe Available Sometime" - it's just too odd to pass up. Now be honest: who here wouldn't have thought "What the...?? Lemme see what's this all about."
BTW, I really like the word "pantaloons". But, I am easily amused - even "trousers" makes me smile.
Parent
Re:Huh? (Score:4, Insightful)
It brings to mind the Ogden Nash rhyme:
A child does not have to be very clever
to realise that "soon" means "never".
Parent
Re:Huh? (Score:5, Funny)
Parent
Re:Huh? (Score:5, Funny)
I'd feel sufficiently menaced by villains flying in on those things as to call them "practical" in the super-villainy market.
Of course they'd have to come in black... and a laser beam would be a nice option.
Parent
Not shark (Score:3, Funny)
He's from NZ after all.
Anyway it doesn't look very practical at all - the two guys hardly ever let go of the thing.
Re:Huh? (Score:5, Funny)
IMHO it's "very practical", in the sense that how practical can strapping your ass to a 200-hp gas engine with two washing machine-sized rotors really be?
Parent
Re:Huh? (Score:5, Insightful)
They get around the whole 'jet' naming problem by saying that 'This thing flies on a jet of air'. Yep, and I love my home latpop computer, it's so super... so it's a supercomputer.
Parent
Re:Huh? (Score:4, Insightful)
Parent
Needs stability control (Score:5, Interesting)
Lucky the $100k includes a couple of guys to hold it for you!
I suspect he either needs a fly by wire computer that manages stability or a third fan. Either way I think we're a wee way off from a production model.
Not necessarily (Score:3, Informative)
The old style peroxide jetpacks don't require fly by wire control because just like this one they have the centre of gravity BELOW the exhausts so the pilot is effectively dangling down beneath. All that would happen if he let go of the controls is that it would probably weave around a bit at random but its unlikely to go upside down or completely out of control.
Finally, something for my Flying Car (Score:5, Funny)
Excellent, now my mechanic will be available to get to my flying car (which is also coming "soon") no matter where it is.
I for one... (Score:4, Funny)
... welcome our hearing-impaired jetpack flying overlords.
My news is far more important! (Score:5, Funny)
Okay, so it's not so much an android as a small two foot tall robot.
And by 'robot'.. I mean a cat wearing a cardboard box.
------------------ See! I can make my inventions sound grandiose by making things up, too!
Re:My news is far more important! (Score:4, Funny)
We kan haz pitchers, or DO NOT BELEEV!
Parent
Didn't the myth busters try to make one and failed (Score:3, Insightful)
Didn't the myth busters try to make one and failed at it?
Re:Didn't the myth busters try to make one and fai (Score:4, Insightful)
Besides, the mythbusters fail to reproduce a lot of things, even when they know before hand it's not really a myth but actual fact.
Parent
Re:Didn't the myth busters try to make one and fai (Score:5, Interesting)
If I remember the episode correctly, the point of that particular myth wasn't so much whether they could build a working "jetpack," but specifically, if they could do so using some instructions they found on the internet which claimed a person could successfully do so with inexpensive, commonplace parts. What they found was that the instructions were too vague to serve as anything more than guidelines, and even after going over budget to get better quality parts, their machine still had an unacceptable thrust-to-weight ratio and so could not fly with a human passenger.
While they "busted" the feasibility of that particular set of plans, they didn't really attempt to rule out a jetpack altogether. With the resources for proper parts, and the time for proper testing, it's undoubtedly possible to build a working jetpack/rocketbelt/ducted fan harness thing. The issues with personal flight systems have not so much centered around possibility as practicality.
Parent
I Read TFA ... And Lawled (Score:5, Funny)
In June 1997, seven weeks after the birth of his second child, Mr. Martin figured his prototype was now powerful enough to lift its first flier, so long as that person weighed less than 130 pounds. So he turned to his wife. "I said, 'Hey, Vanessa, what are you doing tonight?"
Mrs. Martin agreed to be her husband's levitating guinea pig.
She said she felt, in a way, that she had conquered it - "the taming of it, that's so exciting." It was, she said, "probably the best experience of my life."
Doesn't say a lot about being married to Mr. Martin or Mr. Martin's prowess in the sack, does it?
Re:I Read TFA ... And Lawled (Score:5, Funny)
Never know, she could have joined the 3-feet high club with Mr. Martin ....
Parent
Re:I Read TFA ... And Lawled (Score:5, Funny)
Never know, she could have joined the 3-feet high club with Mr. Martin ....
What you mean one jetpack each? I am not sure they are designed for...in flight refueling.
Parent
Re: (Score:3, Funny)
The following would have been better:
In June 1997, seven weeks after the birth of his second child, Mr. Martin figured his prototype was now powerful enough to lift its first flier, so long as that person weighed less than 13 pounds. So he turned to his wife. "I said, 'Hey, Vanessa, where's baby?"
The now ex Mrs. Martin said, "No. I don't think so."
Pedantry (Score:4, Funny)
"It is also not, to put it bluntly, a jet. 'If you're very pedantic,"' Mr. 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.
Certainly one is permitted a bit of license in terminology. In fact, if you really get down to it, Jet Li is not actually a jet either.
Re:Pedantry (Score:4, Funny)
The New York Jets, Joan Jett, Jet The Band, and Jet's Pizza are also not jets. Jet Blue and The Jetsons are under review. Jet Clampett is a misspelling, and Jethro Tull doesn't understand the question.
Are we finished here?
Parent
Jet Packs & You (Score:5, Insightful)
The concept of a personal flying machine (e.g. Cars, Bikes, Jet Packs) is two fold at the moment.
1) Energy / Power (inc. Storage & Delivery)
2) Safety
Now I'm going to assume for the sake of this post that we could solve the second one if it was viable to do anyway.
The real kicker is really energy. We need a very rich energy source that is cheap, light, small in volume, and safe.
We can often tick two or three of those boxes but no energy source comes remotely close to hitting all four. Hydrogen for example is light, small in volume, but there are questions over safety and cost.
If we invented some kind of completely safe energy source that had the energy output approaching a nuclear reactor and weighted very little we could be in flying cars within a few years.
But frankly such dreams are far off.
Re:Jet Packs & You (Score:4, Interesting)
Parent
Re:Jet Packs & You (Score:4, Insightful)
"Hydrogen for example is light, small in volume..."
No, actually, that's exactly wrong. Being light by definition means it is NOT "small in volume". It takes a huge volume of H2 in room temperature gas form to store a similar amount of energy to a heavier molecule. The volume problem is why it's a pain to store unless you go to cryogenics, hydrides, or other complicated systems.
Parent
Re: (Score:3, Informative)
Why, again, does this need to be something you carry on your back instead of something you step into?
Gyrocopters can be made very small, they can land almost vertically (and in a controlled manner with the engine out), the ones with pre-rotators and collective controls can take off near vertically (the ones that can only do the former need only a few
Re:Jet Packs & You (Score:5, Insightful)
Hydrogen for example is light, small in volume, but there are questions over safety and cost.
Actually, Hydrogen is light, huge in volume, very safe, and inexpensive. There's a reason it was used to fly blimps, you know.
And before someone goes around throwing the hindenburg in everyone's faces, keep in mind that it was painted with rocket fuel, and that more than half the people on board survived the crash. The same cannot be said for your average airplane.
What gets me though, is that in the face of a personal flying machine that flies around in a video, and is capable of doing so for half an hour, you go on about how personal flying machines aren't possible. Flying cars are known as Helicopters, and your average person could likely afford a hot air balloon. Personal flying machines are everywhere - from cessna's to hang gliders. They're just not as ubiquitous as automobiles, nor as practical for getting around.
Parent
$100k? (Score:5, Interesting)
Consider the total cost of a private pilot's license is about $10k, and the cost of a used Cessna 172 can be had for about $50k [aso.com] in great condition (which, keep in mind, can carry four people, or 2-3 people with some gear, pretty comfortably), I think that the jetpack would have a hard time selling.
I suppose that there could be some niche market for this sort of thing though...though even a well-equipped Harley costs significantly less than many cars still.
Re:$100k? (Score:4, Funny)
Are you kidding?
First, I'd love to ahve one of these, assuming it worked as promised.
Second,... ah crap, I don't know, I just want one.
Parent
Re:$100k? (Score:5, Insightful)
Someobody that is going to buy this isn't to buy it in place of a cessna.... it's an expensive toy, albit a very expensive one.
Parent
Re: (Score:3, Insightful)
If you want to talk impractical, look at the Segway. The thing costs over $5000 (USD), and for what, cause you're too lazy to walk somewhere, or too uncoordinated to ride a bicycle? Why not buy a moped for a hell of a lot cheaper?
This will fall into the same niche market as the Segway.
Re:$100k? (Score:4, Informative)
Unless your driveway is in the sticks, you'll only be able to take off and land this thing there once. After that, the neighbors will have taken out restraining orders preventing you from operating it near them.
Parent
Re:$100k? (Score:4, Interesting)
Parent
Re: (Score:3, Interesting)
Who are these mythical 4 people who fit in a 172? I guess if two of them are small children then yes, but no luggage! :-)
Note that I said, "can carry four people, or 2-3 people with some gear" The jetpack can carry just one person with little to no gear.
A pilot and me in a 172 on a day that is over seventy degrees and the pilot starts thinking about how much fuel he can have and still get off the ground.
Interesting pilot. I used to fly with my housemate who belonged to an aero club. We took Cessna 150s a
Murderer (Score:5, Funny)
My neighbors can't even handle driving SUVs, but the roads are full of them (and the hell they've made of driving among them).
Turning these people into missiles with jetpacks is a great argument for prioritizing personal force field research.
Re:Murderer (Score:4, Funny)
They will only be a problem for a little while. Mistake will weed them out very quickly.
In the mean time, stay indoors.
Parent
Jetpack?!? (Score:3, Informative)
Re:Jetpack?!? (Score:4, Interesting)
In the article it said that the height was limited to allow people to practice at lower altitude. And I think I recall the limit being at 6 feet so far. This statement appears to be about learning to control it at 3 feet before trying to take it 3000 or in the case of the test 500 feet.
There's a good chance soon we'll have a more sensational article about a 500 ft flight soon. Hopefully it won't be part of an obituary.
Parent
Re:Jetpack?!? (Score:4, Insightful)
Parent
Re: (Score:3, Interesting)
Ground effect applies to airplanes, helicopters and of course hovercraft.
Ands rockets. Lunar module pilots had to either cut their power or throttle right down to land on the moon. Ground effect was significant over the last couple of metres.
Gasoline?!? (Score:5, Funny)
I think you mean... (Score:4, Funny)
That's no jetpack... (Score:3, Informative)
Although, having read the article, that may be much more simple than an actual jet-engined jetpack for the time being.
-Aly.
MythBusters (Score:3, Informative)
If you can't wear it, what's the point? (Score:4, Interesting)
Anyway, I'd maintain that the point of a jetpack that makes it especially cool is that it's a pack, as in a back-pack. You thus have air mobility without a vehicle that you have to leave behind once you land. For example, you can strap it on, fly then land in a parking lot, walk into a store and then walk out and take off. If the jetpack needs to be left in a parking space and you can't just bring it wear it with you then it defeats the purpose.
There are already ultra-light helicopters and they do effectively the same thing. All that makes a jetpack special is that it is "truly" wearable. And in order for this to happen you need to keep the weight reasonable - like under a couple hundred pounds at the very most. A person can carry one third of their weight on their back with relatively good comfort and endurance. They can carry more if it's for a short period of time and they're not going very far. If it's an issue of carrying the thing up to your office or something then it might be able to weigh a significant amount of body weight. Still, it could cause injury if it were dragged very far.
To achieve this you need a very light weight jet engine with a very high SFC. (Specific Fuel Consumption). To this end there is one jet engine which stands out, the Williams FJ-22. It weighs only 85 lbs, it has 700+ lbs of thrust and it's reported to have a very high fuel effeciency. High enough for a jetpack? Not known. The unfortunate thing about the little jet is that it only made it to the prototyping phase and after the largest client for the jet, Eclipse Aviation, pulled out, the design was shelved. Thus, it seems that such an engine won't be avaliable in the near future.
Re:Jet Packs Are Still Hype! (Score:5, Informative)
It barely gets off the ground too though
Parent
Nope, there's a backup (Score:4, Informative)
Parent