Jack wrote:
Greg Arnold wrote:

When you are thermalling, a headwind tends to move you upwind in
relation to the airmass.

Why then does my GPS record very nice little loops, the centers
of which parallel the movement of the average wind during thermaling
and move DOWNwind?



Jack

It might be just my imperfect thermalling technique, but it seems to me
that slight upwind adjustments must be made to keep from falling out of
the thermal. This is due to the fact, I believe, that you are not going
up as fast as the air, so you are sinking into a part of the thermal
that has left the ground more recently, and so has not drifted as far
downwind.

But what do I know?