A Simple Fast Response Anemometer

Abstract

Techniques are considered for measuring unsteady ground winds specifically for the purpose of defining inputs for the dynamic load problem encountered by booster vehicles on the launch pad. It is shown that the drag sphere type anemometer is ideally suited for such measurements because (1) it is responsive to the higher frequency wind fluctuations which conventional anemometers do not generally follow and (2) the input quantity of interest, that is, the dynamic pressure, is measured directly by such an instrument. Some development and field experience recently acquired at the National Aeronautics and Space Administration, Langley Research Center, is presented for two different types of drag-sphere anemometers. The merits in using a perforated rather than a continuous smooth-surface sphere as a drag sensor are indicated.