Final answer:
Early air traffic control methods included visual signals, two-way radios, procedural control, and non-radar separation techniques, with rudimentary rules for maintaining distance and following specific routes.
Step-by-step explanation:
Early methods of air traffic control were much more manual and simple compared to today's sophisticated systems. Initially, controllers used visual signals, such as flags and light signals, to communicate with pilots. Then, as radio technology developed, two-way radios became an integral tool for controlling aircraft. Procedural control was also used, where controllers gave pilots instructions for headings, altitudes, and speeds to maintain separation. With the advent of radar after World War II, radar control allowed for much more precise tracking and guidance of aircraft.
A non-radar separation was also common, which relied on time intervals and known aircraft speeds to ensure that planes stayed a safe distance from each other. At the same time, basic rules, such as maintaining a minimum distance between airplanes and following specific flight altitudes and routes, helped keep aircraft sufficiently separated. These methods laid the foundation for the more advanced air traffic control systems in use today.