Conquest Over Ice.-Plane Talk, a publication by Consolidated Vultee Aircraft Corporation, reminds us that ice on wings has always been a hazard that airmen dreaded almost more than anything else. The war has increased exposure to that hazard. For it has made it necessary to fly planes at great altitudes where intense cold prevails; to fly them in far northern regions; to fly them in the icy mists that overhang northern seas; and to fly them regardless of weather conditions. In the middle 30’s a de-icer was invented that was the best approach to the icing problem up to that time. It consisted of a giant rubber overshoe fitted over the leading edges of the wings and other parts, where ice interferes with the aerodynamics of the plane. By inflating and deflating the “overshoe” the ice was cracked after it was formed. Hence the name de-icer. But this ingenious device could be regarded only as a makeshift. It did not prevent formation of ice. It did not overcome the loss in lift caused by irregular caking of ice. A new thermal anti-icer is designed to prevent ice from forming at all. It will do this even in temperatures far below zero. Its principle is simple-a matter of heating the leading edges by the indirect USC Although its essence is simple, the practical of formerly wasted exhaust gases. application of this idea has taken six years of research and experiment. The idea was conceived and in part developed by the National Advisory Committee for Aeronautics; the detail work leading to perfection was done jointly by Consolidated Vultee engineers and Lewis A. Rodert, senior engineer of the N. A. C. A. As now made practical, the thermal anti-icer uses the hot exhaust gases to heat air, by means of heat exchangers in the engine exhaust pipes. The air is then circulated through wings and tail surfaces with controlled initial temperatures ranging as high as 350 degrees F. This heated air keeps the aluminum alloy of the leading edges at a temperature of 60 degrees F. (28 degrees above freezing) even when the outside air temperature is 40 degrees below zero. Tests in far northern latitudes have now been completed, with the simple device functioning perfectly. R. H. 0.