Ram Krishnan wrote:
>
> I also remember reading in an R/C
> Modelling magazine (in 1974?) about someone who built a diffrential
> electrostatic field sensor with electrodes mounted on each wingtip. The
> sensors picked up the gradient of the earth's electrostatic field. If
> memory serves, the device was switched in when the plane went into an
> uncontrolled spin, and would correct it to level flight.


The Electrostatic Autopilot was developed by Maynard Hill, of the Johns
Hopkins Applied Physics Lab. They apparently flew it many times,
although the unit was susceptible to unstable weather- eg. thunderstorms
in the vicinity.

There was a full article (schematics, theory, etc.) in a "Journal of
Aircraft" or "AIAA Journal" from the late 70's IIRC.


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            Anton Coetzee
       Anton.Coetzee@vip.co.za

       FibreFlight Composites

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