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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.
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
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.
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)
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
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.
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 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
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
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.
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.