On Friday, October 30, 2015 at 5:00:02 PM UTC-4, jfitch wrote:
On Friday, October 30, 2015 at 1:03:52 PM UTC-7, Mike the Strike wrote:
I should also remind everyone that GPS-derived bearings only work when you are moving with respect to the ground. Just remember this if you're stationary or even moving backwards in wave.

Mike

There are GPS compasses that do not depend on motion for operation. Doubt anyone has one in a glider though.

I don't think there is such a thing as GPS compass, regardless if you are moving or not. GPS is measuring your position, it has nothing to do with measurement of magnetic field.