Dave Martindale wrote:
"Mogens Beltoft" writes:

We use GPS receivers in our gliders, and most of them can find the
wind direction and speed automatically by detecting that you have
made a full 360 degree turn (happens often for gliders when
searching for thermals), and analysing the 360 degree turn you have
made for drift direction and speed.

And I'm certain that the information is used to display a
wind-corrected heading.

So which GPS receivers do this for you?

We use Pocket-Nav http://www.cambridge-aero.com/pocketNAV.htm and
others.

That seems to be an application that runs on an external computing
device, not something that a GPS receiver itself provides.
Interesting, but different.

The GPS receiver is just an standard "mouse", so NMEA data is analysed by
PocketNav to provide the information.

/Mogens