The Design, Construction, and Use of an Ice Crystal Counter for Ice Crystal Cloud Studies by Aircraft

Abstract

An aircraft instrument is described that gives a real-time measurement of the number of ice crystal particles per unit volume in cirriform clouds. Its method of detection is based on the mechanisms of contact electrification, as applied to the collision between a stainless steel wire and an ice crystal. The signal conditioner, which employs a series of integrated circuits, converts the frequency of crystal collisions into a voltage. Several examples of actual flights are shown.