Which Way is That Thermal?

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oups.com...
ContestID67 wrote:
Look at the Themi:
http://www.themi.de/Themi%20Centering%20Device.htm



I do wish that someone who knows the theory behind this gadget would
speak about this, as it would help me understand how best to fly with
it.


I'm not a Themi expert either, though I've flown with one for 6 years or so.
I don't think the Themi uses accelerometers, as mounting the main box is not
position sensitive. It does have a flight logger, barometric pressure
sensor, gps engine, and computer. Thus it can determine wind when circling,
the best lift encountered during the circle, the direction of that lift from
current position, and which way to turn in order to center the lift. Also,
returning to a previous thermal, but at a different altitude, the Themi does
a credible job of determining where the thermal center is based on its
previous experience with that thermal.

The Themi isn't always right, but it's a useful tool nonetheless. Is it
worth the money? If you needed a logger anyway, maybe. Some soaring computer
interface software (Winpilot Pro w/ climb maximizer) already has most of the
Themi thermal centering features. Since I bought Winpilot Pro after the
Themi, I'm flying with both. The Themi has some features WP Pro doesn't
have, and Themi's display requires almost no head down time.. However, if I
already had WP Pro, I wouldn't buy the Themi.

bumper