How do high school students build and fly lifters using high voltage capacitors?

[pellman]

http://jnaudin.free.fr/html/lifter1.htm

Many years ago I heard of the supposed "electrogravitic" work of T. Townsend Brown. But my faith in the scientific establishment was too strong for me to go to much trouble to investigate it. I figured if there was anything to it, we'd know by now.

Then some months ago I came across a news article about high school students building and flying these "lifters." The URL above will take you to a site discussing the same kinds of lifters in detail.

Basically, they are very light-weight high voltage capacitors that fly through the air when charged.

What's going on here?

 

[garys_2k]

How they work depends on your belief system. For those determined to find "the answer," they work by somehow bending spacetime and counteracting gravity. For the rest of us it seems that ions are involved.

A recent test showed a lifter did not work in a hard vacuum, but this did not dissuade the hardcore woo-woo crowd. My bet is that the top wire electrode ionizes a mass of air above the foil lower electrode and the entire device rises into the air because of simple electrostatic attraction between the ions and that lower electrode.

 

[Alexander]

I bet they create downwind of ionized air (due to asymmetry of top and bottom).

 

[garys_2k]

Originally posted by Alexander
I bet they create downwind of ionized air (due to asymmetry of top and bottom).

Yes, they do create an ion wind, but it seems to be too weak to fully account for the lift. Hence the "alternate" theories.

 

[Alexander]

Oh, no. That wind is quite strong. Place S shaped wire on a Van-Der-Graaf dome - it starts spinning like crazy.

 

[pellman]

The site also describes tests to measure the ion wind associated witht the device or to eliminate ion wind. Supposedly, ion wind contributes only a few percent of the total force.

 

[russ_watters]

Originally posted by pellman
The site also describes tests to measure the ion wind associated witht the device or to eliminate ion wind. Supposedly, ion wind contributes only a few percent of the total force.

What is the force supposed to be acting ON? If its just supposed to be a one sided force (violation of Newtonian physics) this can easily be verified by levitating the object just above a scale. The scale should read zero. My bet is the scale still reads the approximate weight of the object.

 

[garys_2k]

Originally posted by russ_watters
What is the force supposed to be acting ON? If its just supposed to be a one sided force (violation of Newtonian physics) this can easily be verified by levitating the object just above a scale. The scale should read zero. My bet is the scale still reads the approximate weight of the object.

The intense electric field surrounding the upper small diameter wire electrode does ionize a fair amount of air, and that is directed mostly downward from the oppositely charged "skirt" electrode located below the wire.

As to whether the lifters really do lift, yes, they do. Like I said, its not been "finally" decided just how they do that, but the ion wind alone doesn't seem to have enough oomph to do it. But adding the attractive effect of an "ion cloud" near the wire, where the force is between the cloud (with relatively poor mobility in air) and the charged lifter can account for the force.

 

[E8]

Can somebody clarify what exactly an 'ion wind' is? What creates it, what does it do etc.

 

[pellman]

Originally posted by E8
Can somebody clarify what exactly an 'ion wind' is? What creates it, what does it do etc.

Ditto. Google didn't give me any links that explain what it is.

My WAG is that when you have a strongly positively charged surface, air molecules striking it will lose electrons to the surface due to the attraction, then since the molecules now are net positive they are repulsed away creating a "ion wind."

If this guess is correct, I see no reason why the wind from the "lifters" should even have a preferred direction downward, let alone be strong enough to lift them.

I was thinking that perhaps these capacitors are so light weight yet carry a big enough charge to be lifted by the atmospheric electrostatic field. However, one person I talked to said that the field is such that the ground is relatively negative, sky positive, so since the lifters are net positive, that wouldn't work. Can anyone confirm this about the field?

Still, polarity and field strength aside, it probably wouldn't account for indoor flight.

 

[pellman]

Originally posted by garys_2k
The intense electric field surrounding the upper small diameter wire electrode does ionize a fair amount of air, and that is directed mostly downward from the oppositely charged "skirt" electrode located below the wire.

The skirt is not charged, it is grounded. That's why I say above that there is no preferred direction.

 

[garys_2k]

Originally posted by E8
Can somebody clarify what exactly an 'ion wind' is? What creates it, what does it do etc.

Basically, a breeze of ionized air being repelled, or attracted to, a charge. Classic example is a thumbtack on top of a Van der Graaf generator terminal -- a breeze will be felt coming from the tip of the tack because of the intense ionization at the tip and its subsequent repulsion from the charged terminal.

 

[garys_2k]

Originally posted by pellman
The skirt is not charged, it is grounded. That's why I say above that there is no preferred direction.

Um, sure, and the high voltage source has one terminal grounded as well. If you place the top wire too close to the skirt you get intense sparking -- so there is an intense attractive force between ions charged by the top wire and the nearby grounded, oppositely charged (whatever) skirt.