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Fuelless Flight with Air Submarine?
An anonymous reader writes "Using the same physics principles as submarines, a new company is planning a fuelless air ship. Recent advances in ultra light and strong materials are making this concept a practical reality." There's no question that changes in buoyancy can be used to propel a vehicle, but "fuelless" is going to be tricky.
Isn't that what the sci-fi writers of the 1940s/1950s thought the future would be like? After all, the Empire State Building has a blimp port at the top. I'll stick with good old ozone layer killing cars, thank you.
With engines and small amount of fuel as backup, would you trust this non submarine?
And it rendered on, until the end of its days.
The pontoons will be multiple layers of Kevlar and epoxy, which weigh as little as 1 lb/ft2, around a rigid carbon-fiber airframe
I've heard that there's a really bad problem from lightning strikes if you plane isn't made from an excellent conductor like metal. Various attempts have been made to make non-metal composites that don't get badly damaged by a strike. If this plan goes really high then this will be a problem.
Can some engineer tell me, have they solved this problem or is this idea just hot air?
Like all pain, suffering is a signal that something isn't right
not with the patented "main reversible wind turbine" you won't...energy comes for free when you license that technology.
On the other hand, the ocean gliders that have been mentioned before relied on the relation between temperature and depth. In that case, that energy came from the surrownding water.
This thing is supposed to fly because of a combination of reduced bouyancy (by way of creating multiple vacuum's inside it) and stored energy (by way of a turbine invented by the apparent author).
The turbine is for compressing air, to be used as power storage. I think.
If your craft is dependant on creating a vacuum inside for easy lift, but your power supply is compressed air, don't the two kinda cancel eachother out?
Even if you made it and got it up, what would it be like to try to control a zero-weight plane with mass? I picture it flipping around in the wind like a feather...
The aircraft, still in development, will be similar to a submarine that changes its buoyancy, a form of gravity, to float on the surface of the sea or cruise 300 ft below it.
Stephen J. Mraz, "Senior Editor," is in need of a severe beating. Since when is buoyancy "a form of gravity?"
I stopped reading there. Nothing bothers me more than shitty pseudoscience.
According the the white paper on the "Technology" link:
.0755 pounds per cubic foot lifting capacity for air).
The gravityplane must be very large in order to be lifted by a lighter-than-air lifting gas such as helium that provides a very low amount of lift, thus a small gravityplane can never be built and models of the craft will always be very large. However, a scale model of the gravityplane can be built as a sea glider that is less than 30 foot long that will be capable of holding four passengers. The sea glider can work in water at this small size, because water has a lifting capacity 821 times greater than the lifting capacity of air (62 pounds per cubic foot lifting capacity for water and
If at 30 feet a gravityplane can hold 4 passengers, could this design ever provide a viable means of transport for larger groups of people?
30 feet/4 people = 7.5 feet/person
Thats approx 75 feet per group of 10. Makes for quite a large plane for even medium sized groups.
For cargo I suppose this could be cost effective depending on the maintenance costs and its lifetime. Lets assume that an average person weighs 200lbs (I know it may be too large, but to allow for an optimistic view of the plane's carying capacity).
7.5feet/200lbs ~= 1foot/26lbs
May be good for cargo because shape, size and conditions don't really matter.
Why yes, yes it is. They made flying boats and seaplanes and won the Schnieder Cup race for such three times.
Supermarine History
KFG
A continuous external feed of energy could, in theory, cause a craft to continue to operate without carrying any fuel. Perhaps one could capture energy from a large radiant light source. If only there were such a thing somewhere near the Earth...
However, if one were using efficient solar cells, one might expect such a ship to be black on the top. The inverted-orca coloring pictured would reflect too much light. Service to Seattle may be erratic, but you'd never have to worry about being forced to take a red-eye.
But, you know, this particular one reeks of vaporware. Ignore them until they demonstrate something useful and allow independent observers to examine it. Move along.
I totally agree. I'm not an aerospace engineer, but this seems like a complicated perpetual motion machine to me.
Note one line from the presentation: "gliders have glide ratios of up to 60 to one, and aerostatic balloons have been known to reach altitudes of up to ten miles" (don't know if I got the figures right). That's like saying, "Sports cars have been known to reach speeds of 200+ mph, and bicycles don't require power. Therefore, my hybrid has both qualities."
I'll ask around, but for now I'd call this an interesting way to part an investor from his money. Con artistry is the only truly perpetual motion I've ever heard of.
The article mentions a wind turbine as a mean for "harvesting' the energy from the air-currents. In principle it might even work. Sail-ships are fuelless vehicles capable of circumnavigating the globe (although conversion from wind-power to the vehicle's propulsion is much more straightforward).
Practically? I am really skeptic. Gut-feeling tells me that the turbine-battery-compressor cycle is not efficient enough for self-sustained propulsion.
Disclaimer: IAAEP (I am an experimental physicist)
Ignoring the possibility that these scientists might have to wait for a different set of physical laws before this craft becomes viable, are we to understand that this thingmarine will operate in a constant dive/climb cycle? The cost to fly it could be cheap, but the cleanup costs after a passenger flight would be astronomical. Anti-emetic anyone?
3 more engines.
This plane (if possable) would have a very high glide ratio, so even if it crashes, unless it's a catastrophic failure, it could be a very soft crash landing.
To me this sounds like some intresting scifi, from a wild imagination, but not very well thought out. I'm shure that there will be something like this eventually, but most likeley not too soon.
The vehicle is really just a durigable with wings, I think that lighter than air flight has a potential to be come a really big thing in the next century, and that that is the angle to push, not the fuel-less flight aspect. Imagine taking an air cruise.
Well art is art isn't it, but then again water is water; and east is east; and west is west; and if you take cranberries
I am an aerospace engineer, and you can rest assured that this problem has been adequately dealt with. There's a material of similar thickness and composition to your common anti-static bag for sensitive electrical components. This material can be "shrink-wrapped" onto the Kevlar/epoxy structure. In tests, this material has been known to resist electrical charges of over 12,000 volts. Varying the thickness changes the resistance capacity in a geometric fashion.
...'resist electrical chargesof over 12,000 volts.'?
...'in a geometric fashion.', alright then, that might just work. Sorry, carry on. My bad.
I call bullshit.
Resist 'electrical charges'?
How about conducting sufficent current? At acceptable voltage drops?
...'changes the resistance capacity'..., um, OK. How'er them Flux Capacitors doing? Does this involve Di-Lithium crystals? Oh, wait
Loosing power on only one side is not a picnic even. The remaining engines will have to push harder to maintain speed but this makes the entire aircraft want to turn constantly. Very few runways come in corners.
Gliders on the other hand are designed to ehm well glide. This thing would never suffer an engine failure. Power system (it does have one) fail? Simply glide gently down giving you a far wider range in wich to find a suitable landing splot.
There are many reasons this can fail but worries about safety because of a lack of engines ain't one of them . Note that it isn't a balloon. With wings that size it could exchange hight for speed and with that control over its direction.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
John McPhee wrote an incredible book called "The Deltoid Pumpkin Seed" about the Aeron company, which designed an aircraft that would combine airship technology with a lifting-body style airplane, where the entire body of the plane provides lift. This was a serious design, with no pseudo-science factor. However, the original design (the Aeron 3) was exactly the one described in this post. It was a two-hulled, helium-filled aircraft that would use wings to turn buoyant lift into forward motion. The whole idea was the dream of a christian missionary and pilot who wanted a craft that could deliver bibles and tractors to the third world at minimal cost. The Aeron 3 was destroyed on the ground by high winds before its first test flight. The company didn't bother to rebuild it after they hired some real engineers and hit on the lifting body idea.
I'm not a physics major, I'm a math major, so someone correct me, please, if I'm wrong, but isn't this just yet another take on perpetual motion? Doesn't this proposal violate a couple laws of thermodynamics? And wouldn't this whole deal take some *serious* advances in materials engineering?
I'd be curious to hear if anyone in any of the fields of physics, materials sciences, or aviation would like to offer why this is bordering on revolutionary brilliance, or why this is a totally unmitigated crock of sh--.
Peace.
Chr0m0Dr0m!C
But you can't come back down again unless you compress the helium (which takes work). You could jettison it, but then you'd have to do work to get more helium.
This scheme sounds a bit too much like a perpetual-motion machine. He talks about using energy generated by a wind turbine driven during the glide to alter the buoyancy... IF he'd talked about using, say, solar power to do so, I might believe this was something that at least didn't violate the 2nd law of thermodynamics. But he appears to be claiming he needs no external energy input. That's total crap, and I'm surprised more /. people haven't jumped all over that point.
I mean seriously, didn't anybody take intro phyics in school? If you learned nothing else, you should have learned that you can't get something for nothing. Anybody who says otherwise is selling something worth nothing.
Human genome = 3 billion base pairs = 6 GBit. Windows + Office = 20 Gbit. Which is more impressive?
the huge majority boat/ship types uses buoyancy to stay afloat.
That is part of why I think "buoyant airship" would be apropos
The unofficial
Information storage and retrieval ... no wait ... electronic circuits ... no wait ... ... viruses ... no wait ... worms? ... no wait ... trojans? ... no wait ... cellular automata ... no wait ... um ... um ...
Rotational bearings, reduction gearing, flywheeling. Interestingly, there's more unnatural stuff on the mechanical side than on the information side.
The basis of a perpetual motion machine is that it moves on forever, without any input. The machine will start with either batteries or ground based power to create the vacuum that will allow it to lift off. The initial input.
During flight it will probably regain a percentage of that power from decents, and use that energy to try and create the vacuum again to rise again. This won't be a perfect process, energy will be lost/wasted, so without external input it would eventually need to land. However, It will be receiving external input, mainly solar power. Not directly mind you, but the air currents created by the sun that will work to raise the plane (same way birds can glide for an extended period without flapping their wings). This external input disqualifies it from being a perpetual motion machine, but could allow it to fly for unseemly amounts of time.
paul reinheimer
In order to recover all of that energy you must transfer ALL of it back into the compression of the hydrogen. This is impossible as there are NO 100% efficient "wind turbines" to recover that energy.
Forget about the fact that the plane glides forward - that's just smoke and mirrors. Look at the simpler case where the "plane" falls straight down and doesn't glide at all then ask yourself if it can recover the energy required to get it back to its original altitude. Obviously it can't.
I've made up my mind and now I've got to lie in it.
The design this appears to be a "high" pressure balloon. Nasa is currently researching ultra long duration balloons.i ndex.shtml
:(
http://www.wff.nasa.gov/~code820/uldb/
During the day the sun will heats the helium causing it to expand and the craft floats upward.
During the night the helium cools causing it to contract and the craft falls downwards.
The whole thing looks too heavy to even get off the ground.
These things aren't necessarily for humans to ride in. Wouldn't it be cool to have these things carrying electronics for various purposes? I think that there are already proposals to use derigibles for cell-phone base stations (or whatever they're cslled).
Is a sailboat a perpetual motion machine? Is a windmill a perpetual motion machine? This ship could sail in 3 dimensions and draw power from a turbine. Theoretically, that is possible. Althoug it does need some additional power, hard tack and beans possibly.
But what I don't understand is why he doesn't just create a giant inflatable airplane hybrid, that would probably work better. It could get 90% lift from helium and 10% from forward movement from a turbo fans powered by solar power. The helium ballon aspect of it could be the structural system as well, it would be an active system (inflatable), rather than a very heavy and expensive rigid frame.
Seriously!
No PhD here, but when someone's rambling on for paragraph after long repetitive paragraph about how buoyancy is related to gravity, and never really gets around to a precise description of what the heck this technology is, and keeps referring to "my invention", and alternately refers to himself in the first and third person, this registers pretty high on my BS-o-meter.
I couldn't stand to read too much of it, so maybe I missed something, but this really comes off (to me) as someone who's living in his own little "I know better than all those scientists!" kind of world.
He also talks about building a "cheap" $200k model that works in water in order to prove the airship technology, because it's somehow impossible to build a small-scale model that works in air. I don't think he's thinking too clearly abou this; you can certainly build a cheap model -- just don't expect it to carry people!
Fundamentally, it's still a good idea -- along the lines of the Mars Balloon, and the underwater gliders. But unless he's drawing energy from temperature differences at different altitude, solar heating, or some such, I don't see it working. Trying to get all the energy you need from turbines on the wings is definitely perpetual-motion-machine thinking.
"Orthodoxy is unconsciousness" - Orwell
just as the submarines use energy to compress or expand gas in their bouyancy tanks. This makes them a heat engine (though a slowly cycling one) and subject to the carnot cycle limit.
Actually, as long as you compress and expand gas adiabatically, then the Carnot cycle is irrelevant.
Obviously you cannot make an engine that works in this way, because the point of an engine is (1) to do net work or (2) to cause a heat transfer. So the efficiency of any engine cycle has a Carnot limit.
But the process you have described need not be an engine. In fact, this should be completely obvious. Since there is no net work being done, and no heat transfer, how on earth can you even define an thermodynamic efficiency for the cycle?
And you don't even need to get this complicated. (Slow) compression and expansion of an isolated volume of a gas is reversible and adiabatic. Hence it is isentropic.
This is complete bull! There is no way for this thing to "to stay aloft virtually forever" without some sort of external energy input. Entropy 101.
On a side note, does anyone know how stinking cold it is at 50,000 ft. I don't know for certain but I'm sure is a really small number (in K of course). The heat loss from such a ship must be significant at these elevations. Does anyone know how these folks propose to keep their passengers from freezing? They can't always fly in the sun; they will need some sort of energy source to keep the temperatures at levels suitable for human existence. No, their magical compressors won't be able to do much about this
1. To change bouyance you will have to expend energy somehow.
2. It will be SLOW!!!
3. It will be huge and very dangerous in high winds. Super light and strong composits or not there are limits and this thing would be at the ragged edge.
4. For what? It will be super slow and trains, barges, and ships are very good at moving heavy loads over long distances at slow speeds.
5. No one will fund it. Not only would you have to build this thing but you would have to setup air fields for it. It will not mesh well at the current airports.
One of those great PopSci pipedreams like flying cars.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
Mr. Hunt describes it convincingly. Buoyancy is caused by the differing force with which gravity pulls on heavy and light things. Gravity pulls with more force on heavier things, (F=MA; mass is higher), and less on lighter things. Hence, the heavier thing sinks relative to the lighter thing. Buoyancy.
If you poke around in the faq on the website you will find a link to some perplexing (To me, anyway) descriptions of a new type of wind turbine that this guy has a patent for. Also the team is actually building a proof of concept "Mini-pontoon" as I write this.
I am taking this with a big grain of salt, but I would love to see a carbon fiber ball that is lighter than air due to the vacuum inside.
I say this is the acid test.
Also, Mylar is a great helium holder but I don't think it is good enough to hold up to the repeated crinkling factor.
I deal with Mylar for a living. Once you crush it. It remembers those fracture lines and you can kiss tensile strength goodbye.
It my be the second most common element in the universe but we have a hard time getting it. Helium is mined from limited reserves and like fossil fuels takes millions of years to be produced. For this to actually be reusable (for years to come) it has to use vacuum, or dare I say it, hydrogen. Hydrogen is easy to get hold off and only dangerous when mixed with oxygen. It also has much better lift. But I suppose I shouldn't complain when someone puts forward an idea for clean flight AND gets some attention.
It'll be slow if you are really going "fuelless".
In which case you'd be competing against trains, ships and airships.
Doesn't really matter tho. They're looking for stupid investors- take the money, make an "honest attempt", and walk away.
--
Heck a wind powered blimp would sound even more convincing - just hang an adjustable sail/keel/rotorsail (like gyrocopter) a few hundred feet down, and you could do some sailing, this assumes of course that the winds a few hundred feet down are different enough from the winds above.
Add a windmill or two to get power for miscellaneous stuff for the blimp - assuming different winds at windmill altitude from blimp altitude. Still solar power could be more effective.