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Assume there's a human being who can keep a strong electric potential near to (or on) his skin. Is it possible to use the air-ionizing property, or similar ones solely or mostly solely based on this potential to create lifting power and/or to decrease impact on landing?

If yes, how stable it is? What kind of air support (wings, gliders, etc.) would be absolutely necessary to keep a human being stable?

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This question asks for hard science. All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See the tag description for more information.

  • $\begingroup$ This is really broad. Also, have you done any research on the subject? $\endgroup$ – Aify Mar 2 '16 at 2:16
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    $\begingroup$ @Aify why is it broad? I specified both the concept and the action. I've seen some kind of airplane in a Mythbusters episode that theorietically flew by ionizing air around itself, but couldn't go into details. $\endgroup$ – Katamori Mar 2 '16 at 2:29
  • $\begingroup$ It's broad because you only think you've provided the action (while clearly the question is actually asking for clarification about the action). $\endgroup$ – Aify Mar 2 '16 at 3:24
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    $\begingroup$ With sufficient thrust everything can fly just fine, so you need a lot of electrical current and denser air to lift off(releasing non-pungent wind to overwhelm surface gravity) which is an engineering challenge. $\endgroup$ – user6760 Mar 2 '16 at 4:38
  • $\begingroup$ this doesn't seem broad to me....can this system work seems a pretty straightforward question. $\endgroup$ – James Mar 2 '16 at 15:07
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The hard-science answer: no

If you go to the wikipedia page on this sort of propulsion, Ionocraft, which I arrived at with trivial effort by googling "air ionizing movement", you find several piece of information

In its basic form, the ionocraft is able to produce forces great enough to lift about a gram of payload per watt.

Most ionocraft cannot lift their own powersupplies. A 80kg human being, by this metric, would need 80kW of power. An 80kW power supply weigh substantially more than a human being, so would require even more power to lift. Technically they could generate some lift, but it would be so minuscule compared to virtually every other force involved in flight or landing that you wouldn't even know they turned it on.

Further reading of the wikipedia page gives you the formula for how much force is generated by such a system:

$$F=\frac{Id}{k}$$

Where F is the force, I is the current, d is the distance between annode and cathode, and k is a constant for air (Nominal value $2\cdot10^{-4} m^2 V^{−1} s^{−1}$)

Given that we know how much force it takes to hold a 80kg person aloft, $F=mg=80kg\cdot9.8m/s^2 = 784kN$, what we're really trying to figure out is the current needed. If we rearrange the formula, we get

$$I=\frac{Fk}{d} = \frac{156.8}{d}$$

Where d is measured in meters. This shows the real limit of such propulsion: propulsion goes down as the distance between the anodes and cathodes goes up. To maximize propulsion, you want them to be as close together as possible. However, there's a problem. Too close and the corona effect used for thrust is replaced by lighting style arcing! You can't get much above 30kV/cm, and even at that point you start losing lift due to corona streamers. However, we have to increase the voltage to increase current! It's a catch 22.

In the end, what you really need is more surface area. Actual lifters that have been made in labs might lift upwards of 0.5kg over a square meter of lifting surface. That means our human is going to need 160 square meters of lifting area to lift their weight. That's about the area of a volley ball court!

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  • $\begingroup$ Of course, ion drive is very much practical once you are already moving at a significant fraction of orbital velocity and don't have to contend much with drag. It's a great way to move about in space if you aren't in any particular hurry, because it can be made almost arbitrarily lightweight if you are willing to put up with the reduced thrust. $\endgroup$ – a CVn Mar 24 '16 at 21:59
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Not really practical I am afraid. The basic problem is that this would only ionize a relatively thin layer of air near the skin. So the amount of air ionized would be low compared to the body being lifted. Combine this with the low density air has compared to human body and it is obvious that the acceleration your field gives to the air to offset the acceleration gravity gives your body would have to be very large. (Because the ratio of accelerations has to be the inverse of the masses accelerated and your body has lots of mass compared to a thin layer of air.)

This is not straight out impossible if you can ignore the energy requirement due to handwaving but somehow generating a layer of supersonic plasma with high oxygen content right on your skin seems like a bad idea to me. So you'd really want to keep the energy density way lower than this.

High powered electromasters like Misaka Mikoto (from a Japanese light novel series) might be able to ionize large enough volume of air to get useful propulsion. Would probably be very spectacular and noisy though.

A suit (or other equipment) that would increase the active surface area to mass ratio by few orders of magnitude might help.

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  • $\begingroup$ The name is familiar, I may check it out. Also thanks, I wonder if electromagnetic properties might be used? Of course, only if the floor is made of iron or steel. $\endgroup$ – Katamori Mar 2 '16 at 2:34
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    $\begingroup$ Hard science, please! $\endgroup$ – HDE 226868 Mar 2 '16 at 2:40
  • $\begingroup$ @HDE226868 I'm satisfied with this answer, too; though Cort's one is obviously better. $\endgroup$ – Katamori Mar 2 '16 at 2:57
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    $\begingroup$ @HDE226868 Missed the tag, and have been thinking about adding science, but... Unfortunately the relevant science really is limited to mass of accelerated air times maximum practical acceleration is much smaller than mass of body times Earth gravity. And the only way around this really is to increase the affected air mass either by super power or by increasing the active surface area. Adding math or exact numbers really does not contribute anything here. $\endgroup$ – Ville Niemi Mar 2 '16 at 3:17

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