With few people willing to brave the very real dangers of early air travel, passenger tickets could not support the fledgling U.S. commercial aviation industry. It was postal funds that supported early air travel in America. Prior to 1918, postal officials contracted with companies using established transportation systems. With the introduction of Arial Mail Service, the Post Office Department built the transcontinental flyway, the fields, and the system of beacons. This was a change in how the post office interacted with transportation infrastructure.
When the Post Office Department began airmail, the military was the only organization using aircraft on a regular, large-scale basis in the U.S., so postal officials turned to the army to man and operate the first regularly scheduled airmail flights. After three months, the Post Office Department took control of the Air Mail Service (August 1918).
Banks and businesses immediately recognized the financial advantages of ever-speedier mail service. The general public, on the other hand, viewed the early years of aviation as an adventurous curiosity. For most Americans, flying could not become part of everyday life until schedules and service were regular, reliable, and safe. By financing the postal service's development of airmail routes, aviation advocates in Congress worked with postal officials to create an infrastructure within which the private aviation industry could grow and flourish. In 1927, the routes and system set up by the Post Office Department were turned over to commercial aviation, and the Department contracted with the new aviation companies to carry the mail.
Nancy A. Pope, National Postal Museum