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First Ever Plane With No Moving Parts Takes Flight (theguardian.com)
An anonymous reader quotes a report from The Guardian: The first ever "solid state" plane, with no moving parts in its propulsion system, has successfully flown for a distance of 60 meters, proving that heavier-than-air flight is possible without jets or propellers. The flight represents a breakthrough in "ionic wind" technology, which uses a powerful electric field to generate charged nitrogen ions, which are then expelled from the back of the aircraft, generating thrust. Steven Barrett, an aeronautics professor at MIT and the lead author of the study published in the journal Nature, said the inspiration for the project came straight from the science fiction of his childhood.
In the prototype plane, wires at the leading edge of the wing have 600 watts of electrical power pumped through them at 40,000 volts. This is enough to induce "electron cascades", ultimately charging air molecules near the wire. Those charged molecules then flow along the electrical field towards a second wire at the back of the wing, bumping into neutral air molecules on the way, and imparting energy to them. Those neutral air molecules then stream out of the back of the plane, providing thrust. The end result is a propulsion system that is entirely electrically powered, almost silent, and with a thrust-to-power ratio comparable to that achieved by conventional systems such as jet engines. "I was a big fan of Star Trek, and at that point I thought that the future looked like it should be planes that fly silently, with no moving parts -- and maybe have a blue glow," said Barrett. "But certainly no propellers or turbines or anything like that. So I started looking into what physics might make flight with no moving parts possible, and came across a concept known as the ionic wind, which was first investigated in the 1920s."
"This didn't make much progress in that time. It was looked at again in the 1950s, and researchers concluded that it couldn't work for aeroplanes. But I started looking into this and went through a period of about five years, working with a series of graduate students to improve fundamental understanding of how you could reduce ionic winds efficiently, and how that could be optimized."
In the prototype plane, wires at the leading edge of the wing have 600 watts of electrical power pumped through them at 40,000 volts. This is enough to induce "electron cascades", ultimately charging air molecules near the wire. Those charged molecules then flow along the electrical field towards a second wire at the back of the wing, bumping into neutral air molecules on the way, and imparting energy to them. Those neutral air molecules then stream out of the back of the plane, providing thrust. The end result is a propulsion system that is entirely electrically powered, almost silent, and with a thrust-to-power ratio comparable to that achieved by conventional systems such as jet engines. "I was a big fan of Star Trek, and at that point I thought that the future looked like it should be planes that fly silently, with no moving parts -- and maybe have a blue glow," said Barrett. "But certainly no propellers or turbines or anything like that. So I started looking into what physics might make flight with no moving parts possible, and came across a concept known as the ionic wind, which was first investigated in the 1920s."
"This didn't make much progress in that time. It was looked at again in the 1950s, and researchers concluded that it couldn't work for aeroplanes. But I started looking into this and went through a period of about five years, working with a series of graduate students to improve fundamental understanding of how you could reduce ionic winds efficiently, and how that could be optimized."
This plane's wingspan is already five meters, for just 2.5kg of weight, most of it going to the battery pack. To make it carry more weight, one will have to make it much bigger, which will require much stronger wings, which will make it heavier. And to make things worse, batteries do not get lighter as they discharge.
It's a great toy, but it will be a while before it is useful.
I would be fascinated to know how much thrust that is producing. How variable the thrust is etc.
Does the thrust increase with airspeed? I'd get about 2 mins of flight time on those numbers with a standard battery I use in my wings. But I get about 10-15 mins of flight depending on how much I'm caning it.
In my dream world, this would be used to silently propel solar-powered zeppelins around the world. The zeppelin's buoyancy would support the weight of the batteries used for night-time propulsion.
Of course the problem with that is lithium batteries well-known flammability. But what's the odds of something going wrong with something a simple as a zeppelin?
Because their air cleaners were the first thing I thought of.
I cannot see this as immediately useful for plane construction but I can imagine some uses for it. Most notably, one could power this from a real fuel-powered motor rather than a battery and use it as a secondary propulsion mechanism. So for example, this could maybe eliminate the second rotor on choppers (which is a source of major mechanical complexity and does not do much lifting, just torque balancing).
This looks a lot like the Ionic lifters that were popular in the "anti gravity" circles about 15 years ago. I built a few and they were fun to build, but there isn't any anti-gravity going on here just ion wind. The high voltage was entertaining and the corona was beautiful when the lights were turned off.
The folks at MIT are doing great things. I love it!
https://en.wikipedia.org/wiki/Biefeld–Brown_effect
> "my ass" ... "paper airplanes"
Is it a hint on how you use toilet paper?
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Jet engines have many moving parts, in particular the spinning compressor and turbine. Even ramjets still require fuel pumps.
Efficient engines do. But they could also work without all the complexity they have (pumps etc) as "well" as the engine from the story. Same principle: "a reaction engine is an engine or motor that produces thrust by expelling reaction mass" (wiki)
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How is this even news? These things have been around for like 100 years.
I was pondering what 600 watts at 40,000 volts would be like when it meets a flock of geese.
How would a patent from 1957 be currently held? In a brass frame?
> make it much bigger, which will require much stronger wings, which will make it heavier.
Yeah with planes, if it barely works at small scale, it can't come close to working at a much larger scale. Specifically, doubling the length and width means the weight is eight times as much. It's easy to do things at model scale that are nearly impossible at full size.
Imagine a plane with a rectangular fuselage 10x1x1. Its volume would be ten units, and the weight proportional. "Doubling the size" would be 20x2x2. That's 80 units of volume/weight! Doubling the size makes it 8 times heavier.
I can easily scratch build a model plane from Dollar Tree materials that has a thrust to weight ratio greater than 1. Probably most models have 1 or better thrust to weight. At full scale, only some fighter jets have that kind of capability.
The fact that scaling up by doubling the wingspan means 8 times as much weight means anything borderline capable at 5 meter wingspan because totally unusable at 10 meters. They'll need to either scale it up and show it works, or demo fighter jet level performance at 5 meters to show flight is possible at 10 meter wingspan.
"The order is: engage the silent drive." --Captain Marko Ramius
Yes, for low power apps; but not to propel an airplane.
What causes the mass to be expelled, if it isn't this electrostatic mechanism? You have to pump fuel into them, if nothing else; gravity feed doesn't work when the operating principle of the engine is to create pressure in the combustion chamber to push the burned fuel (or some other mass) out the back.
...your hair would stand on end...
A Merry Christmas, indeed!
Browsing at +1 - no ACs, I ignore their posts. So refreshing!
If they see it in time, they could stick out a robot arm and snag the goose after it gets cooked. It would still be better than most airline food.
Check out my sci-fi/humor trilogy at PatriotsBooks.
To go down, have a change in pressure or temperature suddenly condense all your water.
The first real plane flight wasn't very long either, but it at least carried the weight of a real person.
It's my understanding that Ionic wind doesn't scale very well, and probably can't work for anything larger than a very lightweight toy.
File under 'M' for 'Manic ranting'
That's what a plane is. For an example of a powered, wingless aircraft with no moving parts, see this flying saucer based on a similar principle.
The obvious problem with hydrogen is that it will leak. Just look at how difficult hydrogen is to store and transport. Even if you covered the Zeppelin with a layer of light metal (Al), the hydrogen would still eventually make its way out. Leaking normally would not be a problem - it just goes up. But if the leak is large enough and there is an ignition source, like lightning, then you have a problem. There would not be an explosion right away but a fire would compromise the structural integrity which would eventually lead to ... a very bad event.
A modern airship using Hydrogen would be orders of magnitude safer then the Hindenburg. That being said, still not safe enough. Just use helium and deal with the reduced efficiency.
ehm no. the article mentions pulse jets for example, click on them, and the article about pulsejets mentions how they can be made with few or even no moving parts.
I do believe this is a solution begging for a problem, but I would not say there are hard limits on this application due to batteries in the distant future. We have to extrapolate from current technology that the future will offer wireless power transmission systems. Consider a matrix of ground-based microwave transmitters drawing from solar power that can beam energy to an aircraft such as this in bursts that can charge a meager capacitor. The aircraft is catapult launched, so it only needs to maintain enough energy on board for travelling between energy nodes within the matrix. Actual propulsion would be more efficiently accomplished via traditional means (propeller) for such an aircraft, but my intention here is to highlight that battery scalability should not suppress our freedom to dream of electric aircraft.
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Ah, but you are not supposed to notice the moving parts in the catapult that launched it ;)
And anyway, its far from the first.
A water rocket has 'no moving parts' in the same way, and in summer thousands of them get launched by children daily...
And they dont need a catapult or a perfectly still air environment.
So no, hardly the first.
I mean, they look fine, constructed out of Lego and everything but once you launch one in the air the flight time isn't great and they always fall to pieces where they hit the floor.
This is true of any lifting gas. But hydrogen is a lot easier to replace than helium...
Seven puppies were harmed during the making of this post.
Or just put a net behind the "engine" exhaust...
Seven puppies were harmed during the making of this post.
Is it plausibly useful for very high altitude drones, mars aircraft and the like? What is the effective exhaust velocity? eg is there any regime where it is more efficient than an electric motor and propeller?
Still its a cute concept, even if it isn't practical.
Solar panels will never be efficient enough to give you the electricity you need.
Seven puppies were harmed during the making of this post.
Imagine a plane with a rectangular fuselage 10x1x1. Its volume would be ten units, and the weight proportional. "Doubling the size" would be 20x2x2.
Doubling the size would be 20x1x1. That you allow you to carry twice as much cargo... Probably a lot more than 2x as much since the 10x1x1 aircraft would have fixed size equipment and mechanical stuff that doesn't scale proportionally.
What you suggest is multiplying the size by 8. In practice very large aircraft are economical and not as impractical as your numbers would suggest. Per unit of cargo (e.g. per person) an A380 compares well to a small business jet.
const int one = 65536; (Silvermoon, Texture.cs)
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A modern airship using Hydrogen would be orders of magnitude safer then the Hindenburg. That being said, still not safe enough. Just use helium and deal with the reduced efficiency.
Weird. It's almost as if you believe that helium is cheap and unlimited.
You know that no ship is watertight, right? It's much easier to pump out a bit of water once a day than it is to get a perfect seal.
Blimps could do the same thing, ie. have some tanks of hydrogen on board to keep themselves topped up when some escapes.
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Fixed that for ya'.
That's not really the same. The water is in the plane on launch.
In this plane the ions are generated from the air, there is no loss of mass, so nothing "moving" off the plane (just energy)
No moving parts is easy if we include sail boats. For flying things we also have blimps.
Could this technology also be used as an alternative to the rotating blades currently used in fans? Fans are everywhere, and if this system can scale down effectively and run quieter and more efficient it can have uses in air conditioning, ventilation systems, refrigerators, cars, desktop/laptop computer cooling, basically anywhere we need air to move.
The fuel could probably be coaxed into the combustion chamber by a combination of pressure differentials (carburetor-style, or working with the much higher intake airspeed) and gravity. There are motorcycles and even some cars that don't need a fuel pump.
In this plane the ions are generated from the air, there is no loss of mass, so nothing "moving" off the plane
That's not actually a good thing. Ideally you want your plane to weigh less on landing than on takeoff. Makes things easier on brakes, tires, suspension, etc.
Releasing a lot on nitrogen ions probably isn't the best thing for the environment. Yes, most will combine to NO2 but not all
That's really not a lot of watts; are you trying to give them electrostatic afros??
Right, because weighing less on take off (no fuel) is somehow worse..
You always need fuel. In this case your fuel is electricity stored in batteries. Not sure if you're aware, but I hear those tend to weigh a fair bit. You could in theory use fuel cells and compressed or liquid hydrogen instead of, but I'm not sure that would get you much in the way of weight reduction either. So in either scenario you'll have to seriously beef up your landing gear and brakes, which means added weight, which further reduces efficieny and/or max payload.
You want to minimize wear and tear on landing.. Not on takeoff AND landing.
Yes, that's what I said. By dragging batteries around you are not doing that. Your plane weigh just as much on takeoff as on landing.
idiot.
You seem terribly confused.
Scale model sizes are always done this way. A 1:10 model is 1/10th the length, 1/10th the width, and 1/10th the height, or 1/1000th the volume.
Ah yes, good example.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Not sure how many batteries you'd need to stack up to get 40,000 volts, but I have a hunch the result will be quite a bit heavier than the voltage converter used here.
Well, the on-board batteries will have less energy in them, so there's that.
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> Doubling the size would be 20x1x1. That you allow you to carry twice as much cargo...
If you had an aircraft design at 10x10x1 and tried to scale up the design by only doubling the length, without doubling everything else, it a) wouldn't fly and b) would probably fold in the middle before it made it to the runway.
You can see why if you take it to the extreme and imagine an aircraft 100 feet long, 1 foot wide and 1 foot high. It's obviously not going to be strong enough. Doubling length doubles the lever acting to snap the plane in half. To keep your structural strength, you have to double the width and height when you double the length. That"s why most all planes have basically the same shape, save the "flying wing" design exemplified by the B2.
Weight is HUGELY important in aircraft design, so you don't design something far stronger/heavier than needed, allowing you to double or square the forces without doubling or squaring the strength.
> In practice very large aircraft are economical and not as impractical as your numbers would suggest.
Large aircraft are *possible*, a large team of aeronautical engineering, working with materials scientists, can design one in a few years. Small ones are easy - if you have a piece of paper you can make one right now. You don't even have to know what "wing loading" or even "chord" mean to make a tiny plane that's plenty strong enough while being light enough.
Hobbyists routinely make small scale planes with performance numbers as good or better than the most advanced fighter jets, so that means there is room to scale up. You'd be hard pressed find a model that flies as poorly as a 747 because you'd almost have to suck on purpose to have to be as bad as what the weight penalty of scale does to an aircraft design.
The common housefly has HORRIBLE aerodynamics. If you scaled up a housefly to be a foot long or 100 feet long it would be far too heavy to fly. Yet it gets away with it by being so small. The very small wing area (and horrible chord to width ratio) works only because the fly is only a 3 mm tall.
What this means is that if a powerplant, wing planform, or other element is barely good enough to work in a small scale plane, things only get worse as you scale up.
Btw probably the most important design criteria is wing area . If you scale up a design by doubling length, width, and height, you have squared the wing area and therefore the weight carrying capacity. But you've cubed the weight.
You've got to watch the five-minute video the designer has on YouTube. The best part of the whole thing is how clunky and "garage kiddies" the plane looks, and how they tested it in a local school gym. I couldn't care less whether or not it's practical at the moment. The first automobiles were sometimes followed around by farmers with horse-drawn wagons full of tires and tools, because they were so prone to breakdowns, flats and just plain uselessness.
Here's a link:
https://www.youtube.com/watch?v=boB6qu5dcCw
This is like Kitty Hawk, which is how inventing things that could change the world should be done.
I've calculated my velocity with such exquisite precision that I have no idea where I am.
Can you reverse the principle to make a solid state windmill that generates power with no moving parts?
Blimps could do the same thing, ie. have some tanks of hydrogen on board to keep themselves topped up when some escapes.
Ideally you'd skip the hydrogen storage and instead include a fuel cell and an air compressor. The top of the blimp you're imagining is covered in nanosolar, right?
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
> You build a bigger plane, but don't double wall thickness of your material.
Actually you DO have to double the strength of the walls, and square the strength of certain joints. That's because you've doubled, squared, and cubed the loads they have to withstand.
Consider the wing. A wing 20x2x2 is 8 times as much material as a 10x1x1 wing. Where the wing attaches to the fuselage, a wing root 2 units long is only twice as long as one 1 units. You've only doubled the number of fasteners but multiplied, so each fastener would need to hold four times as much weight, right? Four times the force trying to pull through the material on each fastener? Nope, it's even worse than that - the wing is a lever against the root. So 8x the weight acting via a lever twice as long = 16 times as much force trying to rip the rivets out. But only twice as many rivets.
So you *do* have to double the wall thickness. Or switch to stronger and heavier materials without doubling the thickness.
This will never replace a jet engine or turboprop for passenger planes or other fast vehicles. But jet engines and propellers are not efficient at very high altitudes.
But a solar powered very high-flying blimp or ultra-light that is a platform as a pseudo-satellite for scientific or communications purposes could make use of this system.
Would it be practical to use hot air as the lifting gas?
>In this case your fuel is electricity stored in batteries
Not necessarily - it could be hydrocarbons powering a highly efficient generator. Or a hydrogen fuel cell, or...
The thing about electric vehicles of all types, is that they're really easy to power from whatever energy source happens to be best suited to the situation. One possibility - the military recently invested in the development of a scaled up, multifuel version of the 3hp "Liquid Piston" non-Wankell rotary engine, targeting a 30lb, 30kW generator running at something like 45% thermodynamic fuel efficiency - that'd be a considerably more efficient energy source than electricity from the grid, much less a typical diesel engine (to say nothing of gasoline powered cars), squeezed into 10"(I think?) cube package you can carry with one hand. (For comparison, a Tesla consumes about 15kW cruising at highway speeds).
--- Most topics have many sides worth arguing, allow me to take one opposite you.
They tried that. It was called the Ionic Breeze purifier. It turned out to generate too much ground-level ozone.
Let me take a guess: Perhaps the forces, abrasions, etc. on the landing gear are greater during landing at a given weight than during takeoff at the same weight. In particular, the contact with the ground is more sudden during landing than during takeoff, and more sudden generally means greater force.
By incremental improvement, each of which is worthy of a fresh patent on the new parts. Drug companies have been using this sort of evergreening for decades: introduce an improvement and convince regulators to withdraw the previous product form the market as less safe, so that would-be generic manufacturers cannot compete by producing the previous-generation product.
Not necessarily - it could be hydrocarbons powering a highly efficient generator
You mean, like, say ... a gas turbine?
So you want to keep the gas turbine which is already there, get rid of the fan or prop, add a massive electrical generator, and use that generator to power this new whatchamacallit?
I'm not sure why you expect to improve efficiency with that setup.
... is here.
I'll use a car analogy.
It'll be a toy car powered by two AA batteries. The toy and its engine are green, wouldn't you agree?
I flip a switch and off it goes emitting very little CO2. How neat. I have a small-carbon-footprint car.
--
What processes and procedures in the PAST (here's my focus) caused the car to be here? Well, let's look:
Big fossil-fueled trucks cut the tops off mountains digging out essential minerals, metals, which are shipped by fossil-fueled semis, trains, to massive extractors driven by natural gas or coal or other fossil fuel.
Fat forward through a lot of fossil-fueled steps, and separate parts and pieces are fossil-fuel delivered to an assembly factory to actually fabricate not only the toy, but the batteries as well.
That's a lot of investment in carbon-positive contribution.
Let's back up and start again at the mountaintop cutters. The drivers got there how? By fossil fuel cars. The people bought good at the convenience store manufactured by _____ ____ (hint: fossil fuel).
In fact, all along the supply line including distribution, (all manner of transportation including air and sea), people arrive in fossil fuel cars.
Even after the toy dies, the goddam thing has to find its way to a landfill via a fossil fuel garbage truck.
--
Back to the story: Look at the carbon-neutral plane fly.
Question: Where did the copper wires come from? Where did the battery come from? Where did the parts and pieces come from?
How did the professor and a series of undergraduates get to the hangar?
Don't get me wrong ... I'm all for a plane with no moving parts and wind turbines and solar panels, etc.
But, goddammit, they have their DNA in fossil fuel and the laws of thermodynamics forbid us from getting something for nothing. /rant
It little behooves the best of us to comment on the rest of us.
>Some extreme mental gymnastics is required to make a claim like that. Interesting toy without clear way for improvement.
Perhaps so. But it doesn't take any mental gymnastics at all to realize that the one sure way to be certain there's no improvement is to simply ignore the technology.
It's an interesting technology. Probably makes more sense with lighter-than-air vehicles than aircraft at the commercial scale, at least for now. However, for now they appear to be looking at developing the technology for small-scale vehicles - consumer/delivery drones that operate nearly silently, rather than filling the skies with their annoying buzzing as they become more common. Maybe they succeed in optimizing it to that point, maybe not. Either way the technology has that much more research behind it against the day the right technologies come together to make it useful. And a bunch of engineering students have some hands-on experience doing genuine cutting-edge research towards developing a potentially useful technology.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
And how do you think the ions are generated?
Most of its weight was battery, and yes the flight time was very short. It used to its electrical potential to make the ions.
Which, it seems, is very very very inefficient..
It looks like MagnetoHydroDynamics (MHD) approach that power Russia's recently announced missiles.
In reciprocating engines (like cars and motorcycles), the engine actually creates a vacuum on the intake stroke, so as long as the gas can drain into the carburetor by gravity, it can get sucked into the engine just fine. In fact one of the standard methods for driving a jeep out of the bush when its fuel pump dies is to position a can of gasoline on top of the engine and siphon it into the carb. Carburetors are seldom used these days, with fuel injectors having taken their place; I'm not sure injectors can work with a low pressure gas input.
Not sure this would work with a jet engine. Possibly if you injected the fuel into the air flow at the intake, instead of where it's normally injected (into the high pressure section, i.e. after the compressor). But I don't know enough about how jet engines work to know whether the fuel pre-mixed with air in the low pressure section could be prevented from igniting too soon.
It certainly would not work with a rocket engine, where the combustion chamber is under high pressure. Indeed, one of the main components of a liquid fuel rocket engine is a turbo pump (actually, a pair of turbo pumps: one for the fuel and one for the oxidizer).
Jet engines have at least one moving part. Realistically, they will have more than that, in the fuel control system.
Rocket engines don't have to have any moving parts. Jets do.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Not sure how many batteries you'd need to stack up to get 40,000 volts,
They're ~3.6 volts per cell for the most common chemistry used in vehicle applications today. Sometimes they will take up to 4.1 volts/cell. But the batteries also have internal resistance...
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Yeah, not much use for it right now, but the Wright brothers' initial technology wasn't that useful, either. A century later, some people consider propeller driven aircraft reasonably functional..
Sometimes boldness is in fashion. Sometimes only the brave will be bold.
The ionocraft was first demostrated in 1964: https://www.youtube.com/watch?... An interesting development would be the creation of a shape that allows redirecting the ions flow in any desired direction: up, down, left, right
If you start with 10 x 1 x 1,
* One way to double the volume is to go to 20 x 1 x 1.
* Doubling the dimensions gives you 20 x 2 x 2 (as well as eight times the volume).
Doubling the "size" is ambiguous, so I wouldn't be too hard on the O.P.
That that is is that that that that is not is not.