Discussion in 'Hangar Flying' started by cluttonfred, Nov 21, 2018.
Aircraft and bug zapper all in one!
Hmmm. Looks interesting. But it may be more drag than thrust? :ermm:
Popular Mechanics had an article way back in 1964 about that. A fellow had built a small machine that could hover. It was extremely light and the power supply was on the ground and power fed via a pair of wires to the thing. As usual, the magazine played it up far beyond any reasonably expected reality.
90 watts to lift two ounces. Not efficient at all. It uses nearly ten times as much hp per pound as a helicopter does.
It's only taken 56 years to build something that actually flies. I do hope that this recent attempt is a self-contained affair, not something that relies on an extension cord.
I wonder what the thrust to weight ratio of their ion system is
Could the system be integrated into a conventional wing? It might be interesting to use this method to energize the boundary layer.
Neat! I read up a lot on those ion thrusters 15 or more years ago. Even though most folks online were calling them “lifters” and claiming they bent the fabric of space, I was sketching ways to use them for horizontal thrust on a fixed wing airplane. I didn’t really see any practical uses so it never went beyond drawings in the margins of my notebooks.
I thought maybe the concept could be made to work on a penny plane with the wing covered in foil back to its high point and a wire strung an inch ahead of that, possibly powered by a capacitor to keep the weight down but the volts way up. I also considered a much heavier version with a ground-based power unit, basically a dangerous sci-fi control line plane. Anything can be made to fly in control line.
No, no! You re looking at it wrong. It generates ten times as much HP per lb as a helicopter does. Of course, to make it apples-to-apples we'd have to make both craft self sufficient (e.g. add fuel and a tiny .1 oz 90 watt generator to the ion craft). Like you said, the extension cord kinda ruins the magic.
If it can't be integrated into the wing somehow, it's going to cause an awful lot of drag! OTOH, Voidhawk9's idea of boundary layer control might be amazing.
One wonders, however, what happens in clouds, rain, icing conditions, or when flying through smoke. Also, yelling "clear" would take on even more urgency. It would be advisable to drop some kind of grounding element before getting out of the airplane. Great ignition source. If the fuselage got charged even a little bit, flying in an bubble canopy or open cockpit airplane might become a hair raising experience.
Anybody who has a DC high voltage source can make their own ion drive. Just make an s-shape with a wire that's pointed on both ends. Put some kind of socket slightly above the c.g., put it on a pin so it can spin, apply voltage and it goes.
Good to see I'm not the only mad scientist here.
I looked into ion drives 30 years ago. The physics aren't friendly to terrestial applications. Indoor flying is about all it is good for.
Unless you are planning a long, solar powered space voyage...
The plans for these things are usually marketed as "anti-gravity devices" or "electro-gravitic propulsion".
Many years ago the "Myth Buster's" program put that to rest by trying one inside a vacuum chamber. Didn't budge even a millimeter.
Piasecki did some work on this idea
Yeah I never really bought into the anti-gravity bit, all the tests online trying to 'prove' it just looked like exercises in confirmation bias. That and if true, capacitors would exert a force when charged. It's a neat way to generate tiny amounts of thrust though.
And ozone generater.
I don't know about that, as long as pointy features on the charged parts are avoided. If you put lots of points facing backwards, maybe you wouldn't have to have those grids or whatever they are. Just the thing for deoderizing the stinky interiors of huge ships.
The MIT plane flew 60 meters frm a had launch (about 2 meters). That could demonstrate thrust but it could have just as easily demonstrated reduced drag. Plasma actuators for flow control have been under development for quite some time. The idea is usualy to pull a separrated BL back down to the surface but it can also add kenetic energy to the BL which wouls basically increase the Renolds number. A lift to drag ratio of 30:1 would be astonishing for a model at model Rn but at Rn>1,000,000 it's only pretty good. To be convencing the MIT group has to show that it cangaine altitude.
I see that smiley, but you had me going there for a minute. Not enough coffee yet. Nearly one HP of energy required to lift one pound using that system, while a 'copter can do it with a tenth of a horse and Cub with a lot less than that.
30,000 volts. These "new" flying machines seem to be manifestly dangerous. You can choose between being sliced and diced by a quadcopter's rotors, or fried by its ion probes. A complete pilot-processing system would use both!
A bird can sit on a high voltage power line without getting zapped.
If you are in the plane it may not be as dangerous as you think. It has been demonstrated that being inside a metal cage in a high voltage artificial lightening facility, while it is running, is perfectly safe.
Besides, it is not the voltage but the current that gets you.
Next question: Would such a system make your aircraft more or less prone to lightning strikes? onder:
More, you are ionising the air, which is a lightning magnet. On the positive side, the damp air that tends to be around thunderstorms will break down at much lower voltage and drastically reduce your thrust, making you ion-drive aircraft much less likely to be flying...
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