NACA-TN-1393

Abstract

INTRODUCTION <br>Over a period of several years, the NACA has conducted research on the prevention of ice formations on aircraft through the use of heat. Satisfactory wing, tail-surface, and windshield thermal ice prevention systems were designed, fabricated and tested in natural icing conditions for the Lockheed 12-A, Consolidated B-24, Boeing B-17,and Curtiss-Wright C-46 airplanes. (See references 1, 2, 3, and 4, respective. Each design was based on establishing, for clear-air-conditions, a surface temperature rise which experience had shown to be adequate for ice prevention in simulated and natural icing conditions. <br>The NACA at present is engaged in an investigation to provide a fundamental understanding of the process of thermal ice-prevention in order (1) to establish a basis for the extrapolation of present limited test data to higher speeds and various shapes, (2) to provide data for improving the efficiency of thermal ice-prevention equipment, and (3) to provide a wet-air or meteorological basis for the preparation of design specifications for thermal ice-prevention equipment. The research consists of an investigation of the mythological factors conducive to icing, and a study or the heat-transfer processes which govern the operation of thermal ice-prevention equipment for airfoils and for windshield configurations.