vere economic recession of the 1930s caused many airline companies to fail even in the protected environment. The severity of the depression was more than even regulated route structures and fare schedules could overcome (MacKenzie, 1982, pp. 236-246). As a consequence, and again primarily at the behest of the then operating airline companies, government regulation was strengthened in the areas of the formation of airline companies, their ownership, the route structures of separate airline companies, air fares, airline schedules, safety, and other activities (pp. 236-246).
World War II provided new life for the surviving airline companies. The rejuvenation of the international economy brought about by the war also provided a basis for the founding of several new carriers. New trunk, regional, and local carriers were also founded in the United States. After the war, an improved economy and industry regulation created an environment in which few airline companies failed (MacKenzie, 1987, pp. 126-145).
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