On Monday, January 13, 2014 11:17:35 AM UTC-5, Steve Leonard wrote:
On Monday, January 13, 2014 2:34:40 AM UTC-6, krasw wrote:
Yes, theoretically *if* thermals would drift perfectly with wind...

Uh oh. Next problem. If thermals don't drift at the same speed
as the wind, how accurate is that wind speed your computer derrives
from drift while you are thermalling?

Steve

It is well known that thermals do not exactly drift with the wind.
Consider the inertia of the heated parcel of air as it rises through
increasing wind aloft...
Hang-glider pilots have known for decades to fly upwind in thermal
wind shadows.

Not all flight computers use drift while thermalling to estimate
wind! For example, the ILEC SN10 does not...

Hope that helps,
Best Regards, Dave "YO electric"

PS: Steve, how's the first SN10 ever delivered to a customer treating you?