American Airlines, Inc is a major United States airline headquartered in Fort Worth Texas within the Dallas Fort Worth metroplex. It is the worlds largest airline when measured by fleet size revenue scheduled passengers carried scheduled passenger kilometers flown and number of destinations served. American together with its regional partners, operates an extensive international and domestic network with an average of nearly 6,700 flights per day to nearly 350 destinations in more than 50 countries.American Airlines, Inc is a major United States airline headquartered in Fort Worth Texas within the Dallas Fort Worth metroplex. It is the worlds largest airline when measured by fleet size revenue scheduled passengers carried scheduled passenger kilometers flown and number of destinations served. American together with its regional partners, operates an extensive international and domestic network with an average of nearly 6,700 flights per day to nearly 350 destinations in more than 50 countries.