Air and The War FrontA navy aviation training program designed to de velop 30.000 of the toughest pilots in the world annually for the navy and marine corps will be put into operation by May 1, Navy Secretary i Knox announced. Applications for training are now being accepted. Mr. Knox asked U. S. high school youth to aid the navy by producing 500.000 aircraft models of 50 different types of fighting planes to be used in aircraft recognition and range estimation in gunnery practice and for training civilians in aircraft recognition. The office of civilian defense invited college flyers and aviation enthusiasts to participate in the civilian air patrol which is seeking to enlist 90.000 civilian pilots. Sixteen ears is the minimum age for enrollment for ground service, and 18 for flight e duty. The civil aeronautics administration reported a 60 per cent r increase in private -flvine during 1941.