American Airlines is one of the major US-based airlines headquartered in Fort Worth, Texas, within the Dallas–Fort Worth metroplex. It is the largest airline in the world when measured by scheduled passengers carried, revenue passenger mile, and fleet size. American, together with its regional partners and affiliates, operates an extensive international and domestic network with almost 6,800 flights per day to nearly 350 destinations in 48 countries. American Airlines is a founding member of the Oneworld alliance. Regional service is operated by independent and subsidiary carriers under the brand name American Eagle.