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Jet Packs, Finally On Sale
Bad_CRC1945 writes "The good news: Not one, but two companies are selling jet packs. The bad news: The tech has a long way to go. In the past, potential buyers have been stymied by two problems: Rocket belts aren't for sale, and even prototypes run on modern-day fuel (as opposed to whatever the Jetsons use) which means rocket belts can weigh upwards of 100 pounds, with only enough fuel to stay aloft for under a minute." That second problem's still with us, but the article hints that jet-fuel options (for the brave) could considerably extend users' time aloft.
What exactly is the point of jetpacks supposed to be? They don't seem to be useful for any civilian or military purposes that other technologies aren't more appropriate. Is the obsession with jetpacks just about being like a comic book superhero?
... and then they built the supercollider.
Why do people think that jet fuel is some futuristic stuff? It is basically kerosene.
A not so big secret is that jet engines became popular, not because they were super-efficient, but because they could burn crappy cheap jet fuel. Thus a less efficient jet engine could run faster and cheaper than a piston-engined aircraft.
Less exciting? WTF.
On a full tank of hydrogen peroxide the belt weighs 124 to 139 pounds (the bigger the pilot, the bigger the belt), and provides 30 seconds of flight.
From TFA.
You could stay up to 10 minutes in the air using a proper jet engine, and I remember reading a company developing such a jet pack. However, that's pretty much the same as strapping a Williams X-Jet to your back, which is old technology.
The article appears to be from June 14, 2007. Here's one from this year:
http://www.popularmechanics.com/technology/aviation/diy-flying/martin-aircraft-jet-pack-for-sale
wasent the issue with jetpacks heat and cold burning fule being expensive and not efficient. and for 200k you can buy a sport aircraft liance and all. and can fly it pretty much anywhere unlike a ultralight or jetpack.
... neither of them provide more performance than Captain Keds got out of his when he punched out of the big paper mache football and flew around the field at halftime of Superbowl 1 in 1967. Armadillo Aerospace is top notch in H2O2 propulsion systems, and they aren't building one. I bet there's a good reason.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
In 1980 they said that by 2010 some of us would be using jet packs to commute to work.
What they did not foresee in 1980 was the rise of telecommuting and that those same commuters would not have to travel very far.
Hence the need for only thirty seconds of flight time - it all make perfect sense.
Look, sometimes you need an emergency escape plan, like if the Slayer comes after you just because you try to take over Sunnydale.
That 19-minute jet-turbine version discussed in TFA seems like just the thing one might need after robbing a bank (or a similar institution) in an urban setting.
Just remember not to rob the Gotham National Bank.
Not only is it a mob bank, but Batman has stashed some irradiated bills there too, PLUS Joker already has plans regarding that particular bank.
Mit der Dummheit kämpfen Götter selbst vergebens
You pansy. Strap some JATO rockets on your back and light those suckers!
before I change my sig. I like this one.
So if this is the future...where's my jet pack?
TFA suggests that replacing "inert" hydrogen peroxide with propane will make jet packs more dangerous. Maybe, maybe not, but hydrogen peroxide is a powerful oxidant that attacks many organic compounds (eg people) and can explode. It's not inert by any stretch of the imagination - how useful would an inert rocket fuel be in any case?
Strapping a propane cylinder to your back might not be great either, but I suspect propane is easier to manage.
There's a summary of H202 safety risks here
Virtually serving coffee
The problem with jet packs has been specific impulse. You simply cannot get enough power density into something you can heft on your back and walk around with, at least not without any usable flight time or performance.
I've often thought small jet engines used in RC planes (~40lbs thrust) could be stacked up (6-8) of them to give you a jet pack. But nowadays you can buy a small jet engine designed for UAVs that might weighs 40 pounds and produces 200+ pounds of thrust, these kind of engines have been fitted to gliders.
In terms of a true jet pack. Allowing some weight for fins, a fuel tank and harness you have a 170lb dry weight with three engines. Not much of a real 'pack' then.
So the problems remain, even with the high specific impulse of a jet. You would need to add about your own weight in fuel for one hours flight time.
More ingenious gadget to me, would be a hot air balloon that fits and deploys from a backpack using the same technology that allows large parachutes to be packed into small spaces.
After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
I remember back in the early 80s some DoD contractor had a prototype of a flying "trashcan" like in the Dick Tray comics.
I thought it had some sort of jet engine with a steerable nozzle on the bottom. I think it was probably the Williams X-Jet, but I swear it was painted stealth black.
I used to dream about having one of those, and even as an adult I think it would be so cool to fly one of those around.
I'm guessing that the program probably got canceled because of stability problems. But I would expect that now, with high speed DSPs and gyros like Dean Kamen has used for his scooter and his ubercool wheelchair, that the stability problems could be overcome.
When information is power, privacy is freedom.
The BBC had an interview with the creator of commerical jet packs earlier this year
http://www.youtube.com/watch?v=zGB0csAEs08
If I remember correctly, one of the difficulties faced by the guy who made jetpacks in Mexico was that they were very difficult to mantain stable...
My though is that it should be trivial to equip the thing with an array of small jets (in addition to the big ones used for propulsion) which are connected to a "leveling system" controlled electronically (a few gyroscopes or leveler ICs with some logic will solve the problem).
Ubuntu is an African word meaning 'I can't configure Debian'
Slashdot are posting articles from 2007 as "breaking news" now?
Do they sell trousers with heat proofing around the arse? This seems to be a detail most tv/film jet packs ignore.
"Welcome to our world. We are the wasted youth. And we are the future too." Yes, I know these are stupid lyrics.
I didn't see this mentioned, but this is big news.
The
New Zealand's Martin Aircraft Company
as you probably know has the holy grail of jetson-travel.
I vow to fly one.
martin jet pack
Speed up dude
Since if it's anything close to the purity they used to use in ME-163 (T-Stoff) it'd give you severe chemical burns.
Did you know 80 to 90% of the moderators on slashdot wouldn't recognize a troll even if one dragged them under a bridge.
There is a reason why the term "rocket science" is used to suggest something is more than a bit difficult. But thank you for giving an old-timer a bit of amusement at the expense of what I suspect is one of today's teenagers.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
Dunno about other humans, but for me it would be mostly about the "without a plane around me" part, when I have to travel long distance. Airlines suck, frankly.
I remember the last time I was in an aircraft, with some leg space that was too small even for a 5 ft tall woman who was with us, listening to a screaming kid, and peering down into some airliner joke food that was at most good for a goat, I remembered the famous Da Vinci quote, "When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return." I thought, you can tell the fucker never tasted _this_ kind of flight :p
If a jetpack could get me from here to there without that hassle, I'm all for it.
Heck, I'd even fork over the money for a zeppelin flight, if they can have some more humane accommodations.
A polar bear is a cartesian bear after a coordinate transform.
Bottom line: above a few thousand KW, piston engines for aircraft are simply too complex, expensive and unreliable. The fuel is immaterial.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
The best design in this line was the Bell gas-turbine powered jetpack, powered by a Williams jet engine. Burned jet fuel, ran for about 20 minutes. That was in 1965.
Sam Williams (1921-2009) seems to have been one of the few, if not the only, person who could design good little turbine engines. He did the one for the jetpack, the ones for US cruise missiles, the one for the Army's flying platform VTOL, and his company, Williams International, makes engines for small business jets.
The basic frustration with small turbofan jet engines is that below bizjet size, they don't get much cheaper. That's why general aviation is still mostly piston-powered. The minimum economic size seems to be suitable for a 5-6 passenger bizjet. This is not for lack of trying. About a half-dozen companies have gone bankrupt trying to build small general-aviation jet aircraft.
So a jetpack with reasonable flight time is quite possible, if you're willing to pay what a business jet costs.
http://www.youtube.com/watch?v=vDIojhOkV4w
We Were Promised Jetpacks! http://www.youtube.com/watch?v=U2q-X7DwlqI
How many halftime shows?
How many Bond films?
The clearance system sounds logical. It is not. It is completely arbitrary. -- John Bolton
So I'm not an aviation engineer, but couldn't someone combine a jetpack with some wings so that naturally-occurring lift could be used to reduce fuel consumption once the person was above trees and buildings? Perhaps two 5-foot wings that could be folded and stored in a closet? Would you need 2-3 minutes of fuel in order to take off, stop, and land safely?
No, I will not work for your startup
Well, it occurs to me that I wouldn't really need supersonic speeds or anything, actually. People survive motorcycle trips just fine at, say, 100mph, with just a helmet on. And that's not even particularly fast for a motorcycle.
Thing is, if you sum up the actual average speed for the airplane trip, that is dividing the distance by the total time, including:
- half an hour to an hour driving to the airport (unless you're unfortunate enough to actually live near it. They're loud)
- coming one hour early at the airport, so you can make it through the baroque security checkes in time
- 45 minutes waiting in the airplane because the retards forgot to also pack the luggage (I swear it happened more than once)
- about an hour total time at the other airport, including the waiting for the luggage and all
- driving from the other airport to wherever you actually want to be
etc
then you don't really need ridiculous speed to actually beat the airliner there, if you can go in a straight line and don't deal with road congestions. Thing is, most of the short and medium range flights aren't exactly supersonic either.
I'm pretty sure for example that for a Berlin to Vienna trip, you could actually beat the airlines if you flew in a straight line at 100mph without all those delays. Granted, it's only 325 miles, but that's kinda the point. The jetpack wouldn't be something for when you need to fly from Miami to Seattle, but if you need to do a 300-400 miles trip, and assuming that technology gets to the point where that's possible on a single gas tank, you could actually beat an airline nowadays even on a really tame speed.
A polar bear is a cartesian bear after a coordinate transform.
US$155,000, the cheapest one, for 33 seconds flight time?
How about US$139,000 for one hour? http://jetlev.com/Pages/tech.html
Sure, it's gotta be over water, but it runs on four-stroke engine with ordinary petrol and you get ONE HOUR!
I can't even imagine what adrenaline hungry people will do with these in the future...
/ss
I ordered Jetpack in 1994. I still have my floppy disk, reads 0 bad sectors.
While I agree with your point that the jet is far superior to the ICE engine in everything but low power low cost flight, there's also truth in the OP's original statement about the inexpensive fuel being a valuable benefit of jet turbines. Some time ago, the rail industry started producing Jet Turbine locomotives due to the huge price differential between jet fuel, and diesel fuel. These engines enjoyed the power and weight benefits you describe, with the ability to burn oil that was unsuitable for use in ICE. They were eventually phased out as oil processing techniques improved, and the fuel became more valuable and expensive.
http://en.wikipedia.org/wiki/Union_Pacific_GTELs
The OP also makes a valuable point that Jet Fuel is not expensive or particularly exotic.
If anywhere there was a reason to have jetpacks, Duke Nukem would show us you can do all kinds of things with them like:
(1) fly as high as you can to turn it off and only turn it back on when you are about 100ft from the ground after a freefall,
(2) fly alongside skyscrapers to look for a window to enter, and drink some beer and watch pr0n with some roids.
(3) drop some pipe bombs while flying in the air,
(4) jetpack'd jump-kicks that even Bruce Lee would approve!
(5) even the reptilian(jew) enemies have jetpacks and we think it's only fair,
(6) alien bastards gonna pay for shooting-up my ride!
(7) efficient jetpack technology will be affordable consumer-purchases that make way to fund cars being equipped with redundant arrays of jetpack clusters,
(8) ??
(9) profit!
(10) if Hitler can have an alien bell-UFO to do who-knows-what, then the sons of God need jetpacks and stabilizer-wings to spread the gospel!
Batman has plans for every situation EVER.
In fact, someone "spilling" his plans online was probably his plan all along.
Heck... he has plans about things we can't even imagine happening.
Like DayGlo elephants with machine-guns for limbs raining from the sky. Why would he plan for such an occasion?
Because he is The Batman.
Mit der Dummheit kämpfen Götter selbst vergebens