Originally Posted by
Gauges and Dials
...Which means, as theory pedants like me will point out, GPS cannot tell you what your airplane (or ship, or cell phone) is doing in terms of course or velocity right now, all it can tell you is what your course and velocity were a little while ago.
But now factor in physics. If your course and velocity were to be a whole lot different than what they were one second ago, your neck would have snapped from the acceleration. Since your head didn't snap off your shoulders, we can safely infer that your instantaneous velocity vector right now is not a whole lot different from what it was a little while ago......
As we are being pedantic I suppose we should be clear that "course and velocity" is tautology. There is "course and speed" or there is "velocity".