wrote:
I can definately identify with the horizontal turbulence phenomina that
this discusses. But what I'm talking about is not the same. I've
approached this stable at min-sink and identified lift with the
altemeter. Then the vario rises quickly for about 2 second, then the
bottom drops out and I'm in heavy sink

I'm wondering if the shape/behavior of a thermal changes as it matures
and approaches a cloud (aka tops out)?

-Bruce


Read Mike Borgelt's article:

http://www.borgeltinstruments.com/Gusts.html


--
Regards,

Adrian Jansen


Yes, as others have pointed out, this has been well explored. Certainly
you can imagine that the vertical airstream has to become horizontal
near the thermal top, else you still go up. And so you get horizontal
wind gusts, leading to the vario effects. In fact if you are flying
outward from the centre, you get a tail wind, which corresponds to heavy
sink on the vario. And of course you still get patches of vertical
motion as well, so the altimeter registers too. Things are never simple.

--
Regards,

Adrian Jansen adrianjansen at internode dot on dot net
Design Engineer J & K Micro Systems
Microcomputer solutions for industrial control
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