SECTION I. SUMMARY OF THE NATIONAL REQUIREMENTS THROUGH 1975 We have already passed that point in time where our aviation facilities are capable of safely and efficiently handling all the aircraft seeking to fly. Our present manual system of air-traffic control has been unable to efficiently absorb a growth in aircraft population from 29,000 in 1936 to 90,000 today by patchwork improvements and short-term quick fixes. Today's safety level is provided by imposing arbitrary and costly delays upon civil aviation and restrictions on military aviation which could be very serious in times of national emergency. By 1975, we expect the United States aircraft population to increase to 125,000. As these aircraft become more versatile, productive and dependable, they are flown more each year. While in 1936 there were 5 million takeoffs and landings at the Nation's airports, there are now 65 million, and 115 million are forecast in 1975. (Fig. I, p. 4.) The anticipated 1975 performance spectrum of civil and military manned aircraft ranges from sea level and zero speed to tens of thousands of feet, and speeds greater than sound. (Fig. II, p. 5.) These numbers serve only to indicate the degree of growth that has been experienced in the last 20 years and what is expected in the next 20. To better understand the anticipated loads on the Nation's aviation facilities, it is necessary to focus on specific situations. For instance, during peak hours on busy days in 1956, there were 175 aircraft simultaneously airborne in the New York area (which is the largest airline generating area in the world). It is predicted that by 1975 this number will grow to 370. (Fig. III, p. 6.) Similar statistics for Los Angeles, which generates the largest volume of general aviation in the world, show that in 1956 there were 270 aircraft simultaneously airborne under similar conditions. In 1975, this number will have grown to 700. (Fig. IV, p. 6.) On a busy day in 1956, there were 90 aircraft simultaneously airborne in the en route corridor between New York and Washington. By 1975, there will be about 150 aircraft simultaneously airborne within this same corridor. 50 MILES FIGURE IIIa Radar display showing distribution of airborne aircraft in the New York terminal area at 10:30 am July 14, 1956. Altitude separation is not shown although 85 percent of these aircraft are below 10,000 feet. There are 123 aircraft on this display. 50 MILES FIGURE III Possible distribution of forecast 1975 airborne aircraft in the New York area. Altitude separation is not shown. There are about 350 aircraft shown on this disply. 50 MILES FIGURE IVa Simulated radar display showing 1956 distribution of airborne aircraft in the Los Angeles 50 MILES FIGURE IV Possible distribution of forecast 1975 airborne aircraft in the Los Angeles area. Altitude It is physically impossible for today's aviation facilities to control the 1956 volume of aircraft in such high-density areas-even in clear weather. When |