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178 comments

Who keeps the Metric System down? (-1)

Anonymous Coward | more than 2 years ago | (#36278996)

5000 feet? Really? FFS /.!

Re:Who keeps the Metric System down? (3, Informative)

Anonymous Coward | more than 2 years ago | (#36279100)

I support metric but it's currently the standard world wide in aviation to measure altitude in feet.

Re:Who keeps the Metric System down? (2)

zill (1690130) | more than 2 years ago | (#36279182)

Who keeps the Metric System down?

So to answer GP's question, the aviation industry.

Re:Who keeps the Metric System down? (1)

mijelh (1111411) | more than 2 years ago | (#36279610)

That's true, with some exceptions:
Gliders most commonly use the metric system. Never knew why. And then there are also all those soviet build aircraft using SI (don't know if modern Russian aircraft switched to imperial).
As for airspeed, its even weirder: Commercial aeroplanes universally use Knots, but light aircraft sometimes use mph in America, and km/h in Europe.

Re:Who keeps the Metric System down? (1)

Garridan (597129) | more than 2 years ago | (#36280902)

Waitaminute... a knot is an arc-minute, right? This makes sense at sea level... but does a craft traveling at 1 knot at elevation keep up with a craft traveling at 1 knot at sea level? Or, is an aeronautical knot just 1.151 miles regardless of elevation?

FINALLY!! (2)

jmd_akbar (1777312) | more than 2 years ago | (#36278998)

Now I can FLY!!!


Where was this thing when you needed it the most???

Re:FINALLY!! (3, Funny)

0100010001010011 (652467) | more than 2 years ago | (#36279184)

Now I can FLY!!!

Yeah, but did he solve the icing problems?

Re:FINALLY!! (1)

wagnerrp (1305589) | more than 2 years ago | (#36279380)

Yes. If you get up high enough that icing might be a problem, you pass out yourself from lack of oxygen.

Re:FINALLY!! (1)

vgerclover (1186893) | more than 2 years ago | (#36280016)

I don't know, It doesn't seem to be the bright colored production version. Looking closely, it seems like something a certain shower curtain manufacturer would build.

Re:FINALLY!! (1)

zanian (1621285) | more than 2 years ago | (#36280454)

Yeah, but did he solve the icing problems?

No, in fact Icarus (http://en.wikipedia.org/wiki/Icarus [wikipedia.org]) proves the opposite problem.

Re:FINALLY!! (1)

AftanGustur (7715) | more than 2 years ago | (#36280660)

Yeah, but did he solve the icing problems?

As long as he doesn't try to do Rio - Paris, he should be OK.

Re:FINALLY!! (2)

yog (19073) | more than 2 years ago | (#36279236)

I'm waiting for one of these babies to get me 6 miles to work. Man, would it be nice to fly right over the cars which are all stuck at a light, and buzz a cop car at 70 mph! It would make going to work a joy instead of the tedious trudge to cube farm hell that it is.

Ever since reading Heinlein's The Puppet Masters [wikipedia.org] , I have yearned for a sky car to go hundreds of miles in a few minutes. Of course, I haven't yearned for the accompanying alien parasitic slugs, but like with everything else in life, there's a give and take.

Re:FINALLY!! (1)

Anonymous Coward | more than 2 years ago | (#36280060)

This seems as good a place as any to link to the Martin Jetpack site and the technical specs. [martinjetpack.com]

Designed to conform to FAA Part 103 ultralight regulations (max 5gal fuel, 63mph) but could easily do more
Empty Wt. 250lbs + safety equipment
Useful load: 280+ lbs
Gross Wt. 535+ lbs.
600+ lbs. thrust
10 US gal/hr ; 30 min flight max, 31 mile range (at FAA speed limit)
V4 2L 2-stroke - 200hp, 132lbs, 180+ ft.-lbs.torque 3500-6000rpm
Airframe, fans- mostly carbon/epoxy with some aramid over honeycomb and foam cores, some aluminum fittings and special resins - ~75lbs.
includes roll cage and , high design safety factors, e.g. 5-10 for the fans.
Ballistic parachute,
minimal "avoidance curve" - attempts to ensure accident would be survivable at any altitude

For moderate weight pilots (less than 180lbs.) willing to dispense with FAA part 103 compliance, the craft could carry up to 15 gal. / 90 min.
Target price: $100,000

When we all have jet packs there will be sky jams (0)

Anonymous Coward | more than 2 years ago | (#36280620)

They thought that the car would be a solution to many travel problems and to be fair it is but in town it is often just as slow as a horse and carriage. It was only when a minority of people had cars that there was freedom for the driver. The increasing numbers over the years has made travel in large cities a nightmare.

When you've all got jet packs and are polluting the sky above I'll be outpacing you on my horse on the ground below.

To hear the Kiwi version of events. . . (0)

Anonymous Coward | more than 2 years ago | (#36279010)

A kiwi invented an airplane before the Wright Brothers. His motivation - a quicker way to get to town to the store, instead of walking it. He abandoned the project as too dangerous, when the first flight ended abruptly in a hedgerow, and he considered himself lucky to be alive.

Re:To hear the Kiwi version of events. . . (1)

jmd_akbar (1777312) | more than 2 years ago | (#36279036)

Hedgerow? You sure about that?

I was under the impression that he flew straight into those pines in front of his home.. ;)

Re:To hear the Kiwi version of events. . . (3, Informative)

QuantumLeaper (607189) | more than 2 years ago | (#36279158)

There were a lot of inventors who had a fix wing aircraft before the Wright Brothers but the reason they get to say they invented it is because they could TURN the Wright Flyer. Before that they all flew in a straight line, even the French who didn't believe them, had to admit they won, when the Flyer banked away from a row of trees in Paris.

Re:To hear the Kiwi version of events. . . (2)

91degrees (207121) | more than 2 years ago | (#36279240)

I heard that everyone was shocked when it banked, assuming it had gone out of control.

Although the Wright Brothers first few flights were primarily about flying in a straight line. I wasn't until their third flyer that they managed what could reasonably be considered sustained controlled powered flight (No disrespect to The Wright Brothers. A much more important first.)

Richard Pearse (the kiwi being referred to) did mange to get off the ground for short hops, so it's reasonable to consider that an aviation first as well.

Re:To hear the Kiwi version of events. . . (3, Informative)

Kenneth Stephen (1950) | more than 2 years ago | (#36279404)

You are mostly correct, though you didn't mention the key word: control system. The patent that the Wright Brothers file was not for the shape of the plane, or the engine they used, but for the control systems that let them control the pitch, yaw, and roll of the aircraft. Indeed, controlling the aircraft in stable flight by defining parameters like pitch, yaw, and roll was a key insight of theirs. All their competitors weren't able to achieve stable flight because they were still guessing their way around how to keep their aircraft up and steady, and didn't really have a solution that let them control the aircraft.

Endurance (1)

rossdee (243626) | more than 2 years ago | (#36279012)

So it can go up to 5000 ft if it uses up all its fuel getting there, and then parachutes back down? Still not totally practical.
Also they used a crash test dummy? Couldn't they find a darwin award volunterr?

Re:Endurance (5, Informative)

Anonymous Coward | more than 2 years ago | (#36279064)

Earlier in the program [2:03] Mr. Martin refers to 'flying around for up to 30 minutes'. and at [7:17] in the video there's a call of 800 ft/min climb rate. Methinks you can get a lot better than just up to 3500 ft AGL.

BTW - Aviation authorites have little or no sense of humour. Testing equipment with live (perhaps deserving) volunteers without testing the safety systems will get you shut down, in a very official and unpleasant manner.

Re:Endurance (0)

Anonymous Coward | more than 2 years ago | (#36279176)

Isn't that what third world countries/the middle of the ocean were invented for? Just tell the chosen unpleasant person that they have to travel to * insert name of country or ship in international waters here* because it's part of a reality show. You can't be prosecuted for something that happens in a jurisdiction without aviation laws.

Re:Endurance (1)

LWATCDR (28044) | more than 2 years ago | (#36280374)

Not likely, rate of climb drops a lot as altitude goes up. I am not sure that these engines are turbocharged but if not then the power really starts to drop as you go up as the air gets less dense. But that depends on what you mean by a lot. If you mean 6000 ft above sea level then maybe If you mean 10k I just don't think so. Oh AGL? That is all about safety not performance, above sea level is what really matters from a performance issue.

Re:Endurance (5, Insightful)

Anonymous Coward | more than 2 years ago | (#36279092)

Not quite. That was an test of the new parachute system that is designed for catastrophic situations, something any sane test pilot is going to want before climbing on board and soaring more than a couple feet off the ground. Not sure they discussed flight duration, but soaring to 3000 feet and back to the ground under it's own power is certainly a minimum flight time.

Re:Endurance (0, Troll)

Anonymous Coward | more than 2 years ago | (#36279094)

So it can go up to 5000 ft if it uses up all its fuel getting there

Nonono, didn't you read TFS? It went up to 5000 ft above sea level. What they failed to mention was it started out on land that was already 4990 ft above sea level.

All the way from Darwin? (4, Funny)

definate (876684) | more than 2 years ago | (#36279104)

Darwin is pretty far away from Christchurch. I guess they could get someone from there to volunteer, but I doubt anyone who has won some prestigious award would be into it.

Hell, Google Maps [google.com.au] can't even figure out how to get there!

Re:Endurance (1)

krelvin (771644) | more than 2 years ago | (#36279124)

Did you bother to listen to the video? In it, how long it can fly, PURPOSE of the test, use of the parachute and the crash test dummy.... all explained.

Re:Endurance (1)

jv lee (2048576) | more than 2 years ago | (#36279152)

Practicality isn't necessary at this point in development. Proof of concept has been demonstrated, obviously greater efficiency will need to follow.

landing. (1)

leuk_he (194174) | more than 2 years ago | (#36279370)

Everytime you jump from a building you realize that the flying is not the problem, but the landing is the thing you have to worry about.

Re:landing. (1)

zippthorne (748122) | more than 2 years ago | (#36280286)

Only the first time. If you manage to figure it out before you make it to the bottom, you can apply that solution to all subsequent jumps.

Re:Endurance (1)

Dunbal (464142) | more than 2 years ago | (#36279594)

It climbs at 800 ft per minute (according to the vid) which means 6 minutes to 5000 feet. It carries 45 minutes' worth of fuel (also from the vid). Not sure if you will get an 800 ft/min climb with a full tank though. Also I'm not sure you'd be able to get permission to go to 5000 feet without a private pilot's license.

Re:Endurance (1)

Savantissimo (893682) | more than 2 years ago | (#36280118)

I missed the 800fpm bit, but according to their site, the design is an part103-compliant ultralight which requires no license (though Martin will require a training program when they start selling them), Fuel capacity is 5gal (by FAA requirement) / 30min / ~30mi range.

Re:Endurance (1)

bluemonq (812827) | more than 2 years ago | (#36280494)

I think that's what the limitations "are", but they'll look the other way if you figure out how to get more fuel into the thing.

Re:Endurance (0)

Anonymous Coward | more than 2 years ago | (#36280034)

Keep in mind that 5000ft was above sea level. Since they started out at about 1500ft elevation, the jetpack only had to go up 3500 feet as noted in the video.

dom

Not really a jetpack (3, Interesting)

Anonymous Coward | more than 2 years ago | (#36279082)

A jetpack should be no bigger than a hiker's backpack. This thing is more like a small aircraft.

Re:Not really a jetpack (2)

geogob (569250) | more than 2 years ago | (#36279164)

I think letting pseudo-sci-fi action flicks to set technology and engineering guidelines is neither sane nor practical.

Re:Not really a jetpack (1)

FrootLoops (1817694) | more than 2 years ago | (#36279406)

The word itself seems to have a well-defined meaning akin to "backpack, but one that makes me fly". It almost seems to me this thing should have another name, unless they're planning on making it much smaller and just can't or haven't quite yet.

Re:Not really a jetpack (0)

Anonymous Coward | more than 2 years ago | (#36280626)

Maybe jumpjets - akin to MechWarrior or Starcraft 2's Reaper - looks about the size either would use (Reaper body suit aside).

Re:Not really a jetpack (1)

slick7 (1703596) | more than 2 years ago | (#36279950)

I think letting pseudo-sci-fi action flicks to set technology and engineering guidelines is neither sane nor practical.

This [davidszondy.com] is a jet pack. It was developed by Bell Helicopters in the late 60's.Since there seems to be little information on the power plant it's difficult to critique the system. This design was prior to the T-400 jet engine that is used on the Blackhawk helicopter. I believe the T-400 would be a better power plant.

Re:Not really a jetpack (5, Insightful)

Anonymous Coward | more than 2 years ago | (#36279202)

Look at your smart-phone. Did it *start* that size?

Re:Not really a jetpack (-1, Flamebait)

Anonymous Coward | more than 2 years ago | (#36279284)

Look at a 747. Did it *start* at that size? Oh yeah, wait, it did. Comparing information-processing devices to physical propulsion devices just might be the most retarded thing a non-trisomic adult can do, but yet they do it a lot. Maybe some high school physics could help?

Re:Not really a jetpack (1)

mijelh (1111411) | more than 2 years ago | (#36279654)

Look at a 747. Did it *start* at that size? Oh yeah, wait, it did

No it didn't, it started as the small Wright aircraft. next question?

Re:Not really a jetpack (0)

Anonymous Coward | more than 2 years ago | (#36279904)

That's right, it got bigger. Thanks for being a total moron. Next question?

Re:Not really a jetpack (1)

DerekLyons (302214) | more than 2 years ago | (#36279472)

Apples and oranges. When portable phones were invented, the electronics in them were nowhere near their theoretical size limits. They had room to both shrink and grow in performance.

Jetpacks like this are already very near their theoretical limits just to fly at all. There's no magical chemical fuel waiting in the wings. (Excuse the pun.) There's no magical ducted fan or propeller design that will dramatically increase performance. There's no magical material that will dramatically decrease the weight. Etc... etc...

Hmm... Just watched the full video, and they've palmed a card. It flew to 5000ft *above sea level* - but it took off somewhere above sea level, so the total altitude gained was somewhat less.

Another interesting thing is that in the video, they mention that the unit weighed "250 lbs" (presumably at liftoff) - which is the weight of the *empty* pack. I.E. either he made a mistake, or they're obscuring the weight of the crash test dummy.

Re:Not really a jetpack (1)

wjsteele (255130) | more than 2 years ago | (#36279524)

There's no magical chemical fuel waiting in the wings. (Excuse the pun.) There's no magical ducted fan or propeller design that will dramatically increase performance. There's no magical material that will dramatically decrease the weight. Etc... etc...

I'm curious... how do you know there isn't?

There are a lot of discoveries that have already been made that do exactly what you said. The ducted fan design can be improved... GE is working on several designs that do exactly that. There are materials that do dramatically decrease weight... Carbon Fiber is an example... and the science behind those materials (and others) is continuing on. Don't underestimate the power of the imagination to think things up. If someone sees a problem, an engineer somewhere is working on a solution to it.

Bill

Re:Not really a jetpack (1)

w_dragon (1802458) | more than 2 years ago | (#36279582)

In the end you still need a certain amount of energy to lift a person. No matter how light the equipment is lifting a few hundred pounds in a controlled manner takes a lot of energy, and there are theoretical limits as to how much chemical energy a fuel can hold. If we can get a nuclear or antimatter system down to that size then maybe, but I don't think I'll volunteer to be the one to fly around with that on my back.

Re:Not really a jetpack (1)

Savantissimo (893682) | more than 2 years ago | (#36280506)

And we're nowhere near that limit. Using Frink [futureboy.us] :
535lbs gravity 5000ft -> gal gasoline = 0.0259...
Even assuming 25% efficiency, it's still about 1/10 of a US gallon of gas. (the 200hp Martin engine burns 10gal/hr, so it could be as much as 38% efficient, but the transmission, fans and est.90% throttle pull that figure down.) The actual gas burned, though, to get to 5000 ft was likely about an order of magnitude greater. (~4000ft/800fpm=5min; 10gph*1/12hr=5/6gal)

The energy mostly goes not to lifting the craft from one height to another but rather to accelerating air simply to maintain altitude.

Re:Not really a jetpack (0)

Anonymous Coward | more than 2 years ago | (#36279660)

"I'm curious... how do you know there isn't?"

Do you believe the periodic table of chemical elements to be in error, or missing some elements? You could win every Nobel prize there is if you can prove this. Besides, negative proof like you want is the domain of religion. You don't have a religion about technology, do you? How do you know we can't live thousands of years? Hmm?

Re:Not really a jetpack (2)

Savantissimo (893682) | more than 2 years ago | (#36280292)

The jetpack produces ~600 lbs. thrust at 10 gph = 61lbs/hr.. Empty weight is 250lbs, max takeoff weight is about 535lbs.. A 180lb pilot could carry over 15gal of fuel, sufficient for 90 minutes of flight. The excess thrust over takeoff weight ensures a rapid climb and a decent forward velocity.

The test did not start at high altitude, but on the Christchurch plain in South Island, NZ which slopes gently from 30ft to 1900ft over about 20 to 35 miles. The test takeoff was likely at less than 1000ft, and the craft clearly achieved a substantial height above the ground since it nearly disappeared from view.

Re:Not really a jetpack (1)

bluemonq (812827) | more than 2 years ago | (#36280512)

Actually, if there were improvements in metallurgy and structural design, it could theoretically lighten the whole assembly. Lighter craft means less fuel required/less power required to carry peopple/smaller engine.

Re:Not really a jetpack (0)

Anonymous Coward | more than 2 years ago | (#36279260)

It's not the size of the backpack, but what you can do with it.

Re:Not really a jetpack (1)

mrmeval (662166) | more than 2 years ago | (#36279296)

Baby steps.

They miniaturized jet engines enough to do this and it seems pretty damn good now. Maybe if you can get an engineering degree in fluid dynamics and one in materials science you can develop a continuous detonation wave engine that would be smaller.

Re:Not really a jetpack (1)

wagnerrp (1305589) | more than 2 years ago | (#36279774)

Strap a couple of those miniature jet engines (you'll probably need four for your weight, their weight, and a decent amount of fuel) to your back side, and if you don't burn your legs off, you'll at least start a brush fire. As simple as you make the concept out to be, the reason no one has ever bothered to do that is because no one has figured out a way to resolve the problem of exhaust temperature.

Meanwhile a large ducted fan means significantly lesser power requirement, and similarly, significantly less waste heat you have to deal with.

Re:Not really a jetpack (1)

wagnerrp (1305589) | more than 2 years ago | (#36279718)

There are three factors you have to consider when building something like this: thrust to weight, thrust to power, and jet temperature. Your thrust to weight needs to be above unity, for obvious reasons. The most efficient way to achieve that thrust is a very large fan, at a very low flow velocity. As you try to shrink the unit, your fan becomes smaller, you need higher and higher flow velocity to achieve the same thrust. As you trade size for power, you go from reciprocating ducted fan, to high bypass turbofan, to low bypass turbofan, to turbojet. Each step means reduced efficiency and significantly higher exit temperature.

What you ask is certainly do-able with a turbojet, however your exhaust would start brush fires, melt asphalt, burn off your legs, and depending on how long you stayed near the ground, suffocate you and eventually itself. Now before you say 'but but but... current jetpacks are that small', that's because current jetpacks are all cold gas rockets. They have a tank of hydrogen peroxide and a catalyst. The catalyst causes rapid disassociation, and the resultant jet is a mixture of water vapor and oxygen. There is no combustion to generate heat, and as a result, they are ridiculously inefficient, which is why you get operation times of under a minute.

Re:Not really a jetpack (1)

wagnerrp (1305589) | more than 2 years ago | (#36279776)

It straps onto your back, and it achieves all its lift using a jet. Sounds like a jetpack to me.

A great stunt! (-1)

Anonymous Coward | more than 2 years ago | (#36279098)

Of course, this will never be an everyday practical device. Never mind that we're running out of oil, but the noise alone will either deafen the user after enough time, and cause general nuisance in residential areas... Think about that! Maybe the vibration will cause blood to stop flowing and cause all kinds of long term effects. And isn't it damn cold that high up? So while you're suiting up and putting in your ear plugs, I'll just ride my bike, thanks.

Re:A great stunt! (0)

YrWrstNtmr (564987) | more than 2 years ago | (#36279110)

And isn't it damn cold that high up?

Is it cold in Denver or Madrid?

Re:A great stunt! (1)

morgan_greywolf (835522) | more than 2 years ago | (#36279222)

Never been to Madrid, but, yes, it's damn cold in Denver.

Then again, I live in Florida, so my idea of cold and your idea of cold are probably different. ;)

They should add a wing (4, Interesting)

hackertourist (2202674) | more than 2 years ago | (#36279128)

The pack is big and bulky enough that the addition of a small wing won't make much of a difference. With a wing, you can transition from vertical takeoff using thrust only, to horizontal wing-borne flight which uses much less power (and/or achieves a much higher speed).

Re:They should add a wing (0)

Anonymous Coward | more than 2 years ago | (#36279196)

And a clock. It needs a clock.

Re:They should add a wing (2)

jcwayne (995747) | more than 2 years ago | (#36279306)

My thoughts exactly. Even helicopters and VTOL airplanes spend as little time as possible hovering or in straight vertical motion, both because of how fast it burns fuel and because most (all?) aircraft are more stable when moving horizontally.

Having a wing capable of providing enough lift for an unpowered decent and landing would also make the parachute the last resort that it should be. With the current configuration, the only solution for running out of fuel in flight is deploying the chute. While the landing may be survivable it looked likely to break a few bones.

Re:They should add a wing (1)

drinkypoo (153816) | more than 2 years ago | (#36279334)

I think it should have a folding ultralight wing. That is hard to do but with the small size it should be doable. Then it won't be contributing so much drag during non-wing-based flight. Plus you could ditch it if you had to.

Re:They should add a wing (1)

91degrees (207121) | more than 2 years ago | (#36279350)

I agree. I guess the problem is you'd end up making a VTOL microlight.

Actually that's something that sounds useful but if you want a rocket pack, a microlight isn't the same.

Re:They should add a wing (1)

DerekLyons (302214) | more than 2 years ago | (#36279488)

The pack is big and bulky enough that the addition of a small wing won't make much of a difference.

You're right - a small wing won't make difference, so it's stupid to add one. To get a weight/sq ft ratio low enough for any kind of performance is going to require a fairly large wing. The Rocket Man requires an eight foot wing just to *glide* - and he and his pack are almost certainly lighter (or very close to) the dry weight of just the [Martin] jet pack all by itself.

Re:They should add a wing (1)

wjsteele (255130) | more than 2 years ago | (#36279560)

...big and bulky enough that the addition of a small wing won't make much of a difference...

Actually, that's not true. They are designing it to fit within the US Ultralight category. By adding a wing, you're adding weight, however he is only allowed 254 lbs. The craft is already at 250 lbs. As for speed... again, he is limited to 60mph due to the same restrictions... which he can easily achieve without the addition of a secondary lift device.

Bill

Misread the topic as "Martian", (-1)

Anonymous Coward | more than 2 years ago | (#36279144)

proceeded to feel disappointed after I realised my mistake.

After the first twenty feet... (3, Funny)

kenh (9056) | more than 2 years ago | (#36279174)

After the first twenty feet the ascension would be much easier as my bladder and bowels empty out, lightening the load...

Jetpack or Personal Helicopter (2)

ben_white (639603) | more than 2 years ago | (#36279186)

This is very cool, but it looks more like a personal helicopter than a true jetpack. Certainly could get people into inaccessible areas, but with how much gear, and you couldn't bring much of anything back (like an injured hiker, etc..). Still, quite a feat of engineering. I hope he gets investors!

Re:Jetpack or Personal Helicopter (1)

krazytekn0 (1069802) | more than 2 years ago | (#36279544)

Considering that most previous "jetpacks" used "rockets" instead of "jets" I think this one is closer to a jetpack than the rest IMO.

Re:Jetpack or Personal Helicopter (1)

wagnerrp (1305589) | more than 2 years ago | (#36279800)

A rocket is a type of jet.

Re:Jetpack or Personal Helicopter (0)

Anonymous Coward | more than 2 years ago | (#36280202)

No.

A rocket is a rocket.

A jet is a jet. Which is also a form of engine.

Both are forms of motors, but that is a different story.

Re:Jetpack or Personal Helicopter (1)

zippthorne (748122) | more than 2 years ago | (#36280530)

The "jet" is the plume of air rushing out of the engine that provides thrust.

A rocket is as much of a jet as a turbojet is, except that the rocket generates the jet using internal propellant only, whereas a turbojet, turbofan, etc. use the fuel to power machinery to push some of the surrounding air to form the jet.

Military uses (2)

clyde_cadiddlehopper (1052112) | more than 2 years ago | (#36279234)

Despite Martin Jetpack's talk of its usefulness for remote search and rescue, the real money is for military purposes. This piece [historynet.com] describes the first practical uses of helicopters in Korea for reconnaissance, supply, and medivac. A decade later, the next generation of choppers -- Chinooks and Hueys -- were doing serious delivery work in combat.

I, for one, welcome our new kiwi jetpack flying overlords.

Re:Military uses (0)

Anonymous Coward | more than 2 years ago | (#36280678)

This historical documentary [imdb.com] includes otherwise unreleased footage of German scientists working on a similar rocket pack, but their model backfires and the test pilot is killed. The documentary also includes a Nazi propaganda film that features rocket-pack equipped soldiers flying out to other countries (including the United States) as an unstoppable airborne army.

Interesting Procedure (1)

davidbrit2 (775091) | more than 2 years ago | (#36279300)

The emergency parachute test was also a success.

Personally, I would have performed that test quite a bit beforehand.

Re:Interesting Procedure (2)

kwpulliam (691406) | more than 2 years ago | (#36279428)

Actually you can't test the parachute beforehand..... because the test was for rocket deployment, at altitude, from a machine that was recently operating... anything less (even tossing it from an airplane and triggering the parachute) would be considered only a partial test in aerospace circles.

Re:Interesting Procedure (1)

LWATCDR (28044) | more than 2 years ago | (#36280390)

and it was unmanned. I will say that the ride down didn't look like a lot of fun. Well better than the alternative might be but...

Must...control...credit card... (1)

RogueWarrior65 (678876) | more than 2 years ago | (#36279368)

Maybe I can get a FEMA grant for one for Search & Rescue. Probably cheaper than a Robinson heli. (Yes, I know you can't pick up search subjects but you can't do that in a two-place Robinson either).

The shape is all wrong (1)

MBAslug (184293) | more than 2 years ago | (#36279422)

It needs to look like a jet ski or motorcycle. There should be 4 fans, one on each corner and the user interface would be more like a motorcycle. Let go of the handles and it automatically goes into stabilized mode and your feet would control the brakes and forward acceleration. The whole thing would fit into a standard parking spot. It would have speed determined left and right tilt. In a high speed turn, the rider wants to tilt into the direction of the turn, just like a motorcycle. however, for low speed hover control the rider would lean into the direction he wants to go. Trying to nudge to the left a little to hit the parking spot, just lean to the left.

Why should the feet dangle like a pair of dead twigs. This isn't natural and it puts the operator in an uncomfortable position. No other human operated machine ignore the legs. You also loose two potential inputs for control. And lets be honest, you couldn't shoot at the enemy using this thing. But if it was a motorcycle in the air, you could still control it by leaning your body and controlling forward speed with your feet. That free's up your arms to fire.

And let's be honest, unless we get the army to buy enough of these things to lower the manufacturing cost, we'll never see one in the garage.

Re:The shape is all wrong (0)

Anonymous Coward | more than 2 years ago | (#36279756)

Please read Martin's rationale for the standing position for this aircraft.

Kiwis have always been able to fly (0)

Anonymous Coward | more than 2 years ago | (#36279664)

At 5,000 feet they can fly for nearly a mile before they have to land.

the metric system (0)

Anonymous Coward | more than 2 years ago | (#36280002)

how about you start using it?

What are feet? (1)

LWATCDR (28044) | more than 2 years ago | (#36280328)

Really where is the metric whiners complaining about them using the term feet? Oh because it was a NZ newscast and a NZ citizen using them?

The trouble with jetpacks (1)

Animats (122034) | more than 2 years ago | (#36280372)

The basic trouble with jetpacks is that knees are terrible landing gear. You have to land vertically with a huge mass to stop, and you can't do a controlled fall like a parachute landing. Achieving altitude is not the problem. Landing is the problem.

This thing, like the Solotrek, has landing skids, which take the landing shock. But then it's not really a jetpack. It's more like the Williams X-Jet Flying Platform [wikipedia.org] from the 1980s, probably the best flying machine in this category.

Rifts, Titan Power Armor anyone? (0)

Anonymous Coward | more than 2 years ago | (#36280572)

A prototypical jetpack like Boba Fett's would be used to hop out of or into situations which makes me
wonder: If you integrated a computer control system you might be able to have a small enough hydrogen peroxide jetpack
for a couple hops to and from the skiff/sail-barge. That might be a nice tool for robbing a bank or taking a bounty eh? :)

My favorite "jetpack" is a design from the Rifts megaverse.

http://i90.photobucket.com/albums/k261/ilkoderez/TitanFlyingPowerArmor.jpg

http://i90.photobucket.com/albums/k261/ilkoderez/titan-large.jpg

The wings on this "jetpack" would have to be variable, probably with angle of attack and dihedral-ly
for adjusting the center of gravity and kinestic control. Thrust vectoring is also a must. So that a lot of
stuff to put into a little package but I do think it is possible.

Another one of my favorites is a similar design from "Macross Frontier". In the series they actually use catapults to launch.

Dude, ask Yves Rossy, The only hard part is getting up to speed and landing.

The control surfaces on the Macross Frontier's winged jet pack are sexy; Thrust vectoring rocket engines and
fly-by-wire...

Thats my 2c,
Anonymous

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