I have searched for quite a while and haven't found the answer to this; perhaps someone can help.

I have purchased all the Hitec telemetry pieces, lacking only to buy the GPS sensor. However I have a question. Will the GPS indicate the airplanes airspeed when the airplane is in a vertical climb, or only when the airplane is in horizontal flight?? I imagine the telemetry would indicate zero speed and only increasing altitude when in a vertical climb, but I am not sure. Can anyone clarify??

Thanks,
AV8TOR