3. How do Gill Ultrasonic Anemometers Work?   If, for example, a
North wind is blowing, then the time taken for the pulse to
travel from N to S will be less than from S to N, whereas the W
to E, and E to W times will be the same. The wind speed and
direction can then be calculated from the differences in the
times of flight on each axis. This calculation is independent of
factors such as temperature.  The animation below provides a
simplified time of flight visualisation using the Gill
WindObserver Ultrasonic Anemometer.  4. How to Choose a Gill
Ultrasonic Anemometer >   Anemometer Range  Anemometer Range  R3
Anemometer Range