GPS will show groundspeed only, so it would only be accurate in ZERO
wind conditions. However, I've read that you can compensate for wind by
flying N, S, E and W by using a compass for pointing your plane. You
point the nose in each direction and do NOT correct for wind drift (and
do not use the track readout on your GPS). In other words, you point
the nose for 90 degrees, even if your GROUND TRACK may be 98 degrees
because of wind. Take the 4 readings you get and average them. This
should get you in the ballpark.

Scott


wrote:
Heino & Deanne Weisberg wrote:

I do not believe my airspeed indicator is accurate. Is there a way to
verify/calibrate an airspeed indicator on the ground?
Heino



In the air you can check it vs GPS.