Thread: Thermal mapping
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  #20  
Old April 22nd 04, 12:51 AM
Arnie
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I maybe mistaken, but I think there is something on the competition rules
that forbids the use of tools to "see" thermals ahead of the glider at a
distance of more than a wingspan or so...

So it could be good for centering thermals maybe, like the Themi, but
probably not more than that.

"Bill Daniels" wrote in message
news:2Tuhc.171468$gA5.1991465@attbi_s03...

"Hank Nixon" wrote in message Famous modeler
Maynard Hill studied varying electric charge related to
thermals about 25 or 30 years ago. As I recall he found that there was
a horizontal differential related to thermals.
So- he built a device to sense this and steer the model into the
thermal- so cool!
Then he tested it- When turned on it would not turn aircraft into the
thermal and in fact kept the wings absolutely level. Darn!
Why? It turns out that the vertical voltage potential around the
earth is far stronger than the horizontal one due to thermals.
The good news- He invented the electrostatic wing leveler.
UH


It's fascinating that after decades of looking at thermals with the entire
electromagnetic spectrum, sampling the chemistry, listening to the sounds
and using every known sensing technology, the one consistent

characteristic
is that they are updrafts! The effect of air motion on a glider is still
the only way they can be detected reliably.

LIDAR might open a tiny window for remote sensing. I have thought of a

low
power, short range LIDAR that would sweep left and right of a line angled
down 45 degrees from the horizontal. It would look for bubbles rising

from
below out to 100 meters or so to the front and left or right of the

glider.
This would be enough to have a major impact on the probability of
encountering lift.

It would also be a great help in centering the best lift as it swept the

sky
to the outside of the thermalling turn looking for stronger cores.

At the moment, I know of no way the weight and power consumption would

allow
a LIDAR to fit in a glider.

Bill Daniels